main.js

/*
 * GNU AGPL-3.0 License
 *
 * Copyright (c) 2021 - present core.ai . All rights reserved.
 *
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see https://opensource.org/licenses/AGPL-3.0.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

/*jslint vars: true, plusplus: true, devel: true, nomen: true, regexp: true, indent: 4, maxerr: 50 */
/*global path*/
//jshint-ignore:no-start

define(function (require, exports, module) {
    const ExtensionUtils   = require("utils/ExtensionUtils"),
        EditorManager      = require("editor/EditorManager"),
        FileViewController  = require("project/FileViewController"),
        DocumentManager = require("document/DocumentManager"),
        ExtensionInterface = require("utils/ExtensionInterface"),
        CommandManager     = require("command/CommandManager"),
        Commands           = require("command/Commands"),
        Menus              = require("command/Menus"),
        WorkspaceManager   = require("view/WorkspaceManager"),
        AppInit            = require("utils/AppInit"),
        ModalBar           = require("widgets/ModalBar").ModalBar,
        PreferencesManager = require("preferences/PreferencesManager"),
        ProjectManager     = require("project/ProjectManager"),
        MainViewManager    = require("view/MainViewManager"),
        Strings            = require("strings"),
        Mustache           = require("thirdparty/mustache/mustache"),
        Metrics            = require("utils/Metrics"),
        CONSTANTS           = require("LiveDevelopment/LivePreviewConstants"),
        LiveDevelopment    = require("LiveDevelopment/main"),
        LiveDevServerManager = require("LiveDevelopment/LiveDevServerManager"),
        MultiBrowserLiveDev = require("LiveDevelopment/LiveDevMultiBrowser"),
        NativeApp           = require("utils/NativeApp"),
        StringUtils         = require("utils/StringUtils"),
        FileSystem          = require("filesystem/FileSystem"),
        DropdownButton     = require("widgets/DropdownButton"),
        BrowserStaticServer  = require("./BrowserStaticServer"),
        NodeStaticServer  = require("./NodeStaticServer"),
        MarkdownSync  = require("./MarkdownSync"),
        LivePreviewSettings  = require("./LivePreviewSettings"),
        NodeUtils = require("utils/NodeUtils"),
        TrustProjectHTML    = require("text!./trust-project.html"),
        panelHTML       = require("text!./panel.html"),
        Dialogs = require("widgets/Dialogs"),
        DefaultDialogs = require("widgets/DefaultDialogs"),
        utils = require('./utils');

    const KernalModeTrust = window.KernalModeTrust;
    if(!KernalModeTrust){
        throw new Error("KernalModeTrust is not defined. Cannot boot without trust ring");
    }

    const StateManager = PreferencesManager.stateManager;
    const STATE_CUSTOM_SERVER_BANNER_ACK = "customServerBannerDone";
    const PREF_MD_THEME = "mdViewerTheme";
    PreferencesManager.definePreference(PREF_MD_THEME, "string", "light", {
        description: Strings.MD_VIEWER_THEME_DESCRIPTION
    });
    let customServerModalBar;

    const isBrowser = !Phoenix.isNativeApp;
    const StaticServer = Phoenix.isNativeApp? NodeStaticServer : BrowserStaticServer;

    const EVENT_EMBEDDED_IFRAME_WHO_AM_I = 'whoAmIframePhoenix';
    const EVENT_EMBEDDED_IFRAME_FOCUS_EDITOR = 'embeddedIframeFocusEditor';

    const PREVIEW_TRUSTED_PROJECT_KEY = "preview_trusted";
    const PREVIEW_PROJECT_README_KEY = "preview_readme";

    // holds the dropdown instance
    let $dropdown = null;
    const PREFERENCE_LIVE_PREVIEW_MODE = "livePreviewMode";

    // live preview element highlights preference (whether on hover or click)
    const PREFERENCE_PROJECT_ELEMENT_HIGHLIGHT = CONSTANTS.PREFERENCE_PROJECT_ELEMENT_HIGHLIGHT;
    PreferencesManager.definePreference(PREFERENCE_PROJECT_ELEMENT_HIGHLIGHT, "string", CONSTANTS.HIGHLIGHT_HOVER, {
        description: Strings.LIVE_DEV_SETTINGS_ELEMENT_HIGHLIGHT_PREFERENCE,
        values: [CONSTANTS.HIGHLIGHT_HOVER, CONSTANTS.HIGHLIGHT_CLICK]
    });

    // live preview ruler lines preference (show/hide ruler lines on element selection)
    const PREFERENCE_SHOW_RULER_LINES = CONSTANTS.PREFERENCE_SHOW_RULER_LINES;
    PreferencesManager.definePreference(PREFERENCE_SHOW_RULER_LINES, "boolean", false, {
        description: Strings.LIVE_DEV_SETTINGS_SHOW_RULER_LINES_PREFERENCE
    });

    // live preview link editor and preview preference
    const PREFERENCE_LIVE_PREVIEW_SYNC = CONSTANTS.PREFERENCE_LIVE_PREVIEW_SYNC;
    PreferencesManager.definePreference(PREFERENCE_LIVE_PREVIEW_SYNC, "boolean", true, {
        description: Strings.LIVE_DEV_SETTINGS_LINK_EDITOR_AND_PREVIEW_PREFERENCE
    });

    const LIVE_PREVIEW_PANEL_ID = "live-preview-panel";
    const LIVE_PREVIEW_IFRAME_ID = "panel-live-preview-frame";
    const MDVIEWR_IFRAME_ID = "panel-md-preview-frame";
    const _sandboxAttr = Phoenix.isTestWindow ? "" :
        'sandbox="allow-same-origin allow-popups allow-popups-to-escape-sandbox allow-scripts allow-forms allow-modals allow-pointer-lock"';
    const LIVE_PREVIEW_IFRAME_HTML = `
    <iframe id="${LIVE_PREVIEW_IFRAME_ID}" title="Live Preview" style="border: none"
             width="100%" height="100%" seamless="true"
             src='about:blank'
             ${_sandboxAttr}>
    </iframe>
    `;

    // Mdviewer renders untrusted markdown — tighter sandbox than live preview:
    // no allow-same-origin (prevents malicious scripts from accessing Phoenix context),
    // no allow-forms, allow-pointer-lock (not needed for markdown editing).
    // Communication works via MarkdownSync's own message handler (bypasses EventManager origin check).
    const _mdSandboxAttr = Phoenix.isTestWindow ? "" :
        'sandbox="allow-scripts allow-popups allow-popups-to-escape-sandbox allow-modals allow-clipboard-read allow-clipboard-write"';
    const MDVIEWR_IFRAME_HTML = `
    <iframe id="${MDVIEWR_IFRAME_ID}" title="Markdown Preview" style="border: none"
             width="100%" height="100%" seamless="true"
             src='about:blank'
             ${_mdSandboxAttr}
             allow="clipboard-read; clipboard-write">
    </iframe>
    `;

    if(Phoenix.isTestWindow) {
        // for integ tests
        window._livePreviewIntegTest = {
            urlLoadCount: 0,
            STATE_CUSTOM_SERVER_BANNER_ACK
        };
    }

    // jQuery objects
    let $icon,
        $settingsIcon,
        $iframe,
        $panel,
        $pinUrlBtn,
        $livePreviewPopBtn,
        $reloadBtn,
        $chromeButton,
        $safariButton,
        $edgeButton,
        $firefoxButton,
        $chromeButtonBallast,
        $safariButtonBallast,
        $edgeButtonBallast,
        $firefoxButtonBallast,
        $panelTitle,
        $modeBtn,
        $previewBtn;

    let customLivePreviewBannerShown = false;

    // live Preview overlay variables (overlays are shown when live preview is connecting or there's a syntax error)
    let $statusOverlay = null; // reference to the static overlay element
    let $statusOverlayMessage = null; // reference to the message span
    let $statusOverlayClose = null; // reference to the close button
    let shouldShowSyncErrorOverlay = true; // once user closes the overlay we don't show them again
    let shouldShowConnectingOverlay = true;
    let connectingOverlayTimer = null; // this is needed as we show the connecting overlay after 3s
    let connectingOverlayTimeDuration = 3000;

    function _getLiveEditEntitlement() {
        // in community edition, this may not be present;
        return KernalModeTrust.EntitlementsManager && KernalModeTrust.EntitlementsManager.getLiveEditEntitlement();
    }

    let isProEditUser = false;
    // this is called everytime there is a change in entitlements
    async function _entitlementsChanged() {
        try {
            const entitlement = await _getLiveEditEntitlement();
            const wasProEditUser = isProEditUser;
            isProEditUser = entitlement && entitlement.activated;
            // Sync edit mode with md iframe on entitlement change
            if (_isMdviewrActive && $iframe && $iframe[0] && $iframe[0].contentWindow) {
                if (isProEditUser && !wasProEditUser) {
                    // Just got pro — switch to edit mode
                    $iframe[0].contentWindow.postMessage(
                        { type: "MDVIEWR_SET_EDIT_MODE", editMode: true }, "*");
                } else if (!isProEditUser && wasProEditUser) {
                    // Lost pro — switch to reader mode
                    $iframe[0].contentWindow.postMessage(
                        { type: "MDVIEWR_SET_EDIT_MODE", editMode: false }, "*");
                }
            }
        } catch (error) {
            console.error("Error updating pro user status:", error);
            isProEditUser = false;
        }
    }

    StaticServer.on(EVENT_EMBEDDED_IFRAME_WHO_AM_I, function () {
        if($iframe && $iframe[0]) {
            const iframeDom = $iframe[0];
            iframeDom.contentWindow.postMessage({
                type: "WHO_AM_I_RESPONSE",
                isTauri: Phoenix.isNativeApp,
                platform: Phoenix.platform,
                isPhoenixEmbeddedIframe: true
            }, "*"); // this is not sensitive info, and is only dispatched if requested by the iframe
        }
    });
    StaticServer.on(EVENT_EMBEDDED_IFRAME_FOCUS_EDITOR, function () {
        const editor  = EditorManager.getActiveEditor();
        editor.focus();
    });

    /**
     * this function is responsible to check whether to show the overlay or not and how it should be shown
     * because if user has closed the overlay manually, we don't show it again
     * secondly, for connecting overlay we show that after a 3s timer, but sync error overlay is shown immediately
     * @param {String} textMessage - the text that is written inside the overlay
     * @param {Number} status - 1 for connect, 4 for sync error but we match it using MultiBrowserLiveDev
     */
    function _handleOverlay(textMessage, status) {
        if (!$panel) { return; }

        // remove any existing overlay & timer
        _hideOverlay();

        if(LivePreviewSettings.isUsingCustomServer()){
            return;
        }

        // we dont show the overlays for non HTML-type files
        const currentDocument = DocumentManager.getCurrentDocument();
        if (!currentDocument || !currentDocument.file) { return; }

        const filePath = currentDocument.file.fullPath;
        if (!utils.isHTMLFile(filePath)) { return; }

        // to not show the overlays if user has already closed it before
        if(status === MultiBrowserLiveDev.STATUS_CONNECTING && !shouldShowConnectingOverlay) { return; }
        if(status === MultiBrowserLiveDev.STATUS_SYNC_ERROR && !shouldShowSyncErrorOverlay) { return; }

        // for connecting status, we delay showing the overlay by 3 seconds
        if(status === MultiBrowserLiveDev.STATUS_CONNECTING) {
            connectingOverlayTimer = setTimeout(() => {
                // before creating the overlays we need to do a recheck for custom server
                // cause project prefs sometimes takes time to reload which causes overlays to appear for custom servers
                if(LivePreviewSettings.isUsingCustomServer()){
                    connectingOverlayTimer = null;
                    return;
                }
                _showOverlay(textMessage, status);
                connectingOverlayTimer = null;
            }, connectingOverlayTimeDuration);
            return;
        }

        // for sync error status, show immediately
        _showOverlay(textMessage, status);
    }

    /**
     * this function is init the overlay.
     * so overlay is shown when the live preview is connecting or live preview stopped because of some syntax error
     */
    function _initOverlay() {
        if (!$panel) { return; }
        $statusOverlay = $panel.find(".live-preview-status-overlay");
        $statusOverlayMessage = $statusOverlay.find(".live-preview-overlay-message");
        $statusOverlayClose = $statusOverlay.find(".live-preview-overlay-close");

        $statusOverlayClose.on("click", () => {
            const currentStatue = $statusOverlay.data("status");
            if(currentStatue === MultiBrowserLiveDev.STATUS_CONNECTING) {
                shouldShowConnectingOverlay = false;
            } else if(currentStatue === MultiBrowserLiveDev.STATUS_SYNC_ERROR) {
                shouldShowSyncErrorOverlay = false;
            }
            _hideOverlay();
        });
    }

    /**
     * Show the overlay with the given message and status
     * @param {String} textMessage - the text that is written inside the overlay
     * @param {Number} status - 1 for connect, 4 for sync error but we match it using MultiBrowserLiveDev
     */
    function _showOverlay(textMessage, status) {
        if (!$statusOverlay) { return; }

        $statusOverlayMessage.text(textMessage);
        $statusOverlay.data("status", status);

        // @devansh - commenting this out to not show the status overlays, need to fix later
        // the issue is that status overlay - conneting status was never getting removed on devices with
        // slow connections or sites with heavy videos...
        // $statusOverlay.removeClass("forced-hidden");
    }

    /**
     * responsible to hide the overlay
     */
    function _hideOverlay() {
        _clearConnectingOverlayTimer();
        if ($statusOverlay) {
            $statusOverlay.addClass("forced-hidden");
        }
    }

    /**
     * This is a helper function that just checks that if connectingOverlayTimer exists, we clear it
     */
    function _clearConnectingOverlayTimer() {
        if (connectingOverlayTimer) {
            clearTimeout(connectingOverlayTimer);
            connectingOverlayTimer = null;
        }
    }

    /**
     * Hide the play button and mode dropdown when mdviewer is active,
     * since MD files have their own Edit/Reader toggle in the iframe toolbar.
     * Does not hide in custom server mode (handled by _isMdviewrActive being false).
     */
    function _updateLPControlsForMdviewer() {
        if ($previewBtn) {
            $previewBtn.toggle(!_isMdviewrActive);
        }
        if ($modeBtn) {
            $modeBtn.toggle(!_isMdviewrActive);
        }
    }

    function _updateModeButton(mode) {
        if ($modeBtn) {
            if (mode === "highlight") {
                $modeBtn[0].textContent = Strings.LIVE_PREVIEW_MODE_HIGHLIGHT;
            } else if (mode === "edit") {
                $modeBtn[0].textContent = Strings.LIVE_PREVIEW_MODE_EDIT;
            } else {
                $modeBtn[0].textContent = Strings.LIVE_PREVIEW_MODE_PREVIEW;
            }
        }
    }

    function _initializeMode() {
        const currentMode = LiveDevelopment.getCurrentMode();

        // when in preview mode, we need to give the play button a selected state
        if (currentMode === LiveDevelopment.CONSTANTS.LIVE_PREVIEW_MODE) {
            $previewBtn.addClass('selected');
        } else {
            $previewBtn.removeClass('selected');
        }

        _updateModeButton(currentMode);
    }

    function _showModeSelectionDropdown(event) {
        const isEditFeaturesActive = isProEditUser;
        const currentMode = LiveDevelopment.getCurrentMode();
        const items = [
            Strings.LIVE_PREVIEW_MODE_PREVIEW,
            Strings.LIVE_PREVIEW_MODE_HIGHLIGHT,
            Strings.LIVE_PREVIEW_MODE_EDIT
        ];

        // Only add edit-specific options when in edit mode and edit features are active
        const isEditMode = currentMode === LiveDevelopment.CONSTANTS.LIVE_EDIT_MODE;
        if (isEditFeaturesActive && isEditMode) {
            items.push("---");
            items.push(Strings.LIVE_PREVIEW_EDIT_HIGHLIGHT_ON);
            items.push(Strings.LIVE_PREVIEW_SHOW_RULER_LINES);
        }

        $dropdown = new DropdownButton.DropdownButton("", items, function(item, index) {
            if (item === Strings.LIVE_PREVIEW_MODE_PREVIEW) {
                // using empty spaces to keep content aligned
                return currentMode === LiveDevelopment.CONSTANTS.LIVE_PREVIEW_MODE ?
                    `✓ ${item}` : `${'\u00A0'.repeat(4)}${item}`;
            } else if (item === Strings.LIVE_PREVIEW_MODE_HIGHLIGHT) {
                return currentMode === LiveDevelopment.CONSTANTS.LIVE_HIGHLIGHT_MODE ?
                    `✓ ${item}` : `${'\u00A0'.repeat(4)}${item}`;
            } else if (item === Strings.LIVE_PREVIEW_MODE_EDIT) {
                const checkmark = currentMode === LiveDevelopment.CONSTANTS.LIVE_EDIT_MODE ?
                    "✓ " : `${'\u00A0'.repeat(4)}`;
                const crownIcon = !isEditFeaturesActive ?
                    ' <span style="color: #FBB03B; border: 1px solid #FBB03B; padding: 2px 4px; border-radius: 10px; font-size: 9px; margin-left: 12px;"><i class="fas fa-crown"></i> Pro</span>' : '';
                return {
                    html: `${checkmark}${item}${crownIcon}`,
                    enabled: true
                };
            } else if (item === Strings.LIVE_PREVIEW_EDIT_HIGHLIGHT_ON) {
                const isHoverMode =
                    PreferencesManager.get(PREFERENCE_PROJECT_ELEMENT_HIGHLIGHT) === CONSTANTS.HIGHLIGHT_HOVER;
                if(isHoverMode) {
                    return `✓ ${Strings.LIVE_PREVIEW_EDIT_HIGHLIGHT_ON}`;
                }
                return `${'\u00A0'.repeat(4)}${Strings.LIVE_PREVIEW_EDIT_HIGHLIGHT_ON}`;
            } else if (item === Strings.LIVE_PREVIEW_SHOW_RULER_LINES) {
                const isEnabled = PreferencesManager.get(PREFERENCE_SHOW_RULER_LINES);
                if(isEnabled) {
                    return `✓ ${Strings.LIVE_PREVIEW_SHOW_RULER_LINES}`;
                }
                return `${'\u00A0'.repeat(4)}${Strings.LIVE_PREVIEW_SHOW_RULER_LINES}`;
            }
            return item;
        });

        // Append to document body for absolute positioning
        $("body").append($dropdown.$button);

        // Position the dropdown at the mouse coordinates
        $dropdown.$button.css({
            position: "absolute",
            left: event.pageX + "px",
            top: event.pageY + "px",
            zIndex: 1000
        });

        // Add a custom class to override the max-height
        $dropdown.dropdownExtraClasses = "mode-context-menu";

        $dropdown.showDropdown();

        $(".mode-context-menu").css("max-height", "300px");

        // handle the option selection
        $dropdown.on("select", function (e, item, index) {
            if (index === 0) {
                LiveDevelopment.setMode(LiveDevelopment.CONSTANTS.LIVE_PREVIEW_MODE);
            } else if (index === 1) {
                LiveDevelopment.setMode(LiveDevelopment.CONSTANTS.LIVE_HIGHLIGHT_MODE);
            } else if (index === 2) {
                if (!LiveDevelopment.setMode(LiveDevelopment.CONSTANTS.LIVE_EDIT_MODE)) {
                    if(KernalModeTrust.ProDialogs) {
                        KernalModeTrust.ProDialogs.showProUpsellDialog(
                            KernalModeTrust.ProDialogs.UPSELL_TYPE_LIVE_EDIT);
                    } else {
                        Metrics.countEvent(Metrics.EVENT_TYPE.PRO, "proUpsellDlg", "fail");
                    }
                }
            } else if (item === Strings.LIVE_PREVIEW_EDIT_HIGHLIGHT_ON) {
                // Don't allow edit highlight toggle if edit features are not active
                if (!isEditFeaturesActive) {
                    return;
                }
                // Toggle between hover and click
                const currMode = PreferencesManager.get(PREFERENCE_PROJECT_ELEMENT_HIGHLIGHT);
                const newMode = (currMode !== CONSTANTS.HIGHLIGHT_CLICK) ?
                    CONSTANTS.HIGHLIGHT_CLICK : CONSTANTS.HIGHLIGHT_HOVER;
                PreferencesManager.set(PREFERENCE_PROJECT_ELEMENT_HIGHLIGHT, newMode);
                return; // Don't dismiss highlights for this option
            } else if (item === Strings.LIVE_PREVIEW_SHOW_RULER_LINES) {
                // Don't allow ruler lines toggle if edit features are not active
                if (!isEditFeaturesActive) {
                    return;
                }
                // Toggle ruler lines on/off
                const currentValue = PreferencesManager.get(PREFERENCE_SHOW_RULER_LINES);
                PreferencesManager.set(PREFERENCE_SHOW_RULER_LINES, !currentValue);
                return; // Don't dismiss highlights for this option
            }
        });

        // Remove the button after the dropdown is hidden
        $dropdown.$button.css({
            display: "none"
        });
    }

    /**
     * to close the overflow button's dropdown
     */
    function _closeDropdown() {
        if ($dropdown) {
            if ($dropdown.$button) {
                $dropdown.$button.remove();
            }
            $dropdown = null;
        }
    }

    function _handleLPModeBtnClick(e) {
        e.stopPropagation();
        $dropdown ? _closeDropdown() : _showModeSelectionDropdown(e);
    }

    function _getTrustProjectPage() {
        const trustProjectMessage = StringUtils.format(Strings.TRUST_PROJECT,
            path.basename(ProjectManager.getProjectRoot().fullPath));
        const templateVars = {
            trustProjectMessage,
            Strings: Strings
        };
        return Mustache.render(TrustProjectHTML, templateVars);
    }

    function _isProjectPreviewTrusted() {
        // We Do not show a trust project window before executing a live preview in desktop builds as in
        // desktop, each project will have its on live preview `server:port` domain isolation.
        // Live preview is almost the same as opening a url in the browser. The user opening a project by going though
        // a lot of selection folder picker dialogs should be regarded as enough confirmation that the user
        // intents to open that file for preview via a browser url. The browser security sandbox should
        // take care of most of the security issues as much as any other normal browsing in a browser.
        // Showing a trust window is UI friction for 99% of users. The user confirm dialog also relies on the user
        // taking the decision that an anti-virus/firewall would make- which is not going to end well; and a lot of
        // our users are school students or new devs, who we should assist. Phoenix trust model will heavily rely on
        // us doing the necessary sand boxing whenever possible.
        // A compromised project can have special html that can instruct phoenix to change editor selections and
        // edit only the project files. We will have safeguards in place to detect anomalous large change requests
        // to mitigate DOS attacks coming from the live preview in the future. A malicious project changing its on
        // text only using its own code should be an acceptable risk for now as it cant affect anything else in the
        // system.
        if(Phoenix.isTestWindow || Phoenix.isNativeApp){ // for test windows, we trust all test files
            return true;
        }
        // In browsers, The url bar will show up as phcode.dev for live previews and there is a chance that
        // a malicious project can appear as `phcode.dev` when user live previews. So for every live preview
        // popout tab which shows `phcode.dev` in browser address bar, we will show a trust live preview
        // confirm dialog every single time when user opens live preivew project.
        // Further, since all live previews for all projects uses the same phcode.live domain,
        // untrusted projects can access data of past opened projects. Future plans for browser versions
        // include adopting a similar approach to desktop to dynamically generate URLs in the format
        // `project-name.phcode.live` preventing the past data access problem in browser. This will also let us drop the
        // trust project screen an work the same as desktop apps.
        const projectPath = ProjectManager.getProjectRoot().fullPath;
        if(projectPath === ProjectManager.getWelcomeProjectPath() ||
            projectPath === ProjectManager.getExploreProjectPath()){
            return true;
        }
        const isTrustedProject = `${PREVIEW_TRUSTED_PROJECT_KEY}-${projectPath}`;
        return !!PhStore.getItem(isTrustedProject);
    }

    window._trustCurrentProjectForLivePreview = function () {
        $iframe.attr('srcdoc', null);
        const projectPath = ProjectManager.getProjectRoot().fullPath;
        const isTrustedProjectKey = `${PREVIEW_TRUSTED_PROJECT_KEY}-${projectPath}`;
        PhStore.setItem(isTrustedProjectKey, true);
        _loadPreview(true);
    };

    function _setProjectReadmePreviewdOnce() {
        const projectPath = ProjectManager.getProjectRoot().fullPath;
        const previewReadmeKey = `${PREVIEW_PROJECT_README_KEY}-${projectPath}`;
        PhStore.setItem(previewReadmeKey, true);
    }

    function _isProjectReadmePreviewdOnce() {
        const projectPath = ProjectManager.getProjectRoot().fullPath;
        const previewReadmeKey = `${PREVIEW_PROJECT_README_KEY}-${projectPath}`;
        return !!PhStore.getItem(previewReadmeKey);
    }

    ExtensionInterface.registerExtensionInterface(
        ExtensionInterface._DEFAULT_EXTENSIONS_INTERFACE_NAMES.PHOENIX_LIVE_PREVIEW, exports);

    /**
     * @private
     * @return {StaticServerProvider} The singleton StaticServerProvider initialized
     * on app ready.
     */
    function _createStaticServer() {
        var config = {
            pathResolver: ProjectManager.makeProjectRelativeIfPossible,
            root: ProjectManager.getProjectRoot().fullPath
        };

        return new StaticServer.StaticServer(config);
    }

    // Templates
    ExtensionUtils.loadStyleSheet(module, "live-preview.css");
    // Other vars
    let panel,
        urlPinned,
        currentLivePreviewURL = "",
        currentPreviewFile = '',
        _loadGeneration = 0,
        _isMdviewrActive = false,
        $mdviewrIframe = null; // persistent md iframe, survives HTML preview switches

    function _blankIframe() {
        // we have to remove the dom node altog as at time chrome fails to clear workers if we just change
        // src. so we delete the node itself to eb thorough.
        // Don't destroy the persistent md iframe — just hide it
        if ($mdviewrIframe && $iframe[0] === $mdviewrIframe[0]) {
            MarkdownSync.deactivate();
            _isMdviewrActive = false;
            _updateLPControlsForMdviewer();
            $mdviewrIframe.hide();
            let newIframe = $(LIVE_PREVIEW_IFRAME_HTML);
            $mdviewrIframe.after(newIframe);
            $iframe = newIframe;
        } else {
            let newIframe = $(LIVE_PREVIEW_IFRAME_HTML);
            newIframe.insertAfter($iframe);
            $iframe.remove();
            $iframe = newIframe;
        }
    }

    let panelShownAtStartup;
    function _setPanelVisibility(isVisible) {
        if (isVisible) {
            panelShownAtStartup = true;
            $icon.toggleClass("active");
            panel.show();
            _loadPreview(true, true);
            _showCustomServerBannerIfNeeded();
        } else {
            $icon.toggleClass("active");
            _blankIframe();
            panel.hide();
        }
    }

    function _startOrStopLivePreviewIfRequired(explicitClickOnLPIcon) {
        let visible = panel && panel.isVisible();
        if(visible && (LiveDevelopment.isInactive() || explicitClickOnLPIcon)) {
            LiveDevelopment.openLivePreview();
        } else if(!visible && LiveDevelopment.isActive()
            && !StaticServer.hasActiveLivePreviews()) {
            LiveDevelopment.closeLivePreview();
        }
    }
    function _toggleVisibilityOnClick() {
        let visible = !panel.isVisible();
        _setPanelVisibility(visible);
        _startOrStopLivePreviewIfRequired(true);
    }

    function _togglePinUrl() {
        let pinStatus = $pinUrlBtn.hasClass('pin-icon');
        if(pinStatus){
            $pinUrlBtn.removeClass('pin-icon').addClass('unpin-icon');
        } else {
            $pinUrlBtn.removeClass('unpin-icon').addClass('pin-icon');
        }
        urlPinned = !pinStatus;
        LiveDevelopment.setLivePreviewPinned(urlPinned, currentPreviewFile);
        _loadPreview(true);
        Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "pinURLBtn", "click");
    }

    const ALLOWED_BROWSERS_NAMES = [`chrome`, `firefox`, `safari`, `edge`, `browser`, `browserPrivate`];
    function _popoutLivePreview(browserName) {
        // We cannot use $iframe.src here if panel is hidden
        const openURL = StaticServer.getTabPopoutURL(currentLivePreviewURL);
        if(browserName && ALLOWED_BROWSERS_NAMES.includes(browserName)){
            Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "popout", browserName);
            NodeUtils.openUrlInBrowser(openURL, browserName)
                .then(()=>{
                    _loadPreview(true);
                    _setPanelVisibility(false);
                })
                .catch(err=>{
                    console.error("Error opening url in browser: ", browserName, err);
                    Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "popFail", browserName);
                    Dialogs.showModalDialog(
                        DefaultDialogs.DIALOG_ID_ERROR,
                        StringUtils.format(Strings.LIVE_DEV_OPEN_ERROR_TITLE, browserName),
                        StringUtils.format(Strings.LIVE_DEV_OPEN_ERROR_MESSAGE, browserName)
                    );
                });
        } else {
            NativeApp.openURLInDefaultBrowser(openURL, "livePreview");
            Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "popoutBtn", "click");
            _loadPreview(true);
            _setPanelVisibility(false);
        }
    }

    function _setTitle(fileName, fullPath, currentLivePreviewURL) {
        let message = Strings.LIVE_DEV_SELECT_FILE_TO_PREVIEW,
            tooltip = message;
        if(fileName){
            message = `${fileName}`;
            tooltip = StringUtils.format(Strings.LIVE_DEV_TOOLTIP_SHOW_IN_EDITOR, fileName);
        }
        if(currentLivePreviewURL){
            tooltip = `${tooltip}\n${currentLivePreviewURL}`;
        }
        $panelTitle.text(currentLivePreviewURL || message);
        $panelTitle.attr("title", tooltip);
        $panelTitle.attr("data-fullPath", fullPath);
    }

    function _showOpenBrowserIcons() {
        if(!Phoenix.isNativeApp) {
            return;
        }
        // only in desktop builds we show open with browser icons
        $chromeButton.removeClass("forced-hidden");
        $chromeButtonBallast.removeClass("forced-hidden");
        $chromeButtonBallast.addClass("forced-inVisible");

        $edgeButton.removeClass("forced-hidden");
        $edgeButtonBallast.removeClass("forced-hidden");
        $edgeButtonBallast.addClass("forced-inVisible");

        $firefoxButton.removeClass("forced-hidden");
        $firefoxButtonBallast.removeClass("forced-hidden");
        $firefoxButtonBallast.addClass("forced-inVisible");
        if (brackets.platform === "mac") {
            $safariButton.removeClass("forced-hidden");
            $safariButtonBallast.removeClass("forced-hidden");
            $safariButtonBallast.addClass("forced-inVisible");
        }
    }

    /**
     * Handle preview button click - toggles between preview mode and the user's default mode.
     * PRO users toggle between preview and edit mode.
     * community users toggle between preview and highlight mode.
     */
    function _handlePreviewBtnClick() {
        if($previewBtn.hasClass('selected')) {
            $previewBtn.removeClass('selected');
            const defaultMode = isProEditUser ? 'edit' : 'highlight';
            PreferencesManager.set(PREFERENCE_LIVE_PREVIEW_MODE, defaultMode);
        } else {
            // Currently NOT in preview mode - switch to preview
            $previewBtn.addClass('selected');
            PreferencesManager.set(PREFERENCE_LIVE_PREVIEW_MODE, "preview");
        }
    }

    async function _createExtensionPanel() {
        let templateVars = {
            Strings: Strings,
            livePreview: Strings.LIVE_DEV_STATUS_TIP_OUT_OF_SYNC,
            clickToReload: Strings.LIVE_DEV_CLICK_TO_RELOAD_PAGE,
            clickToPreview: Strings.LIVE_PREVIEW_MODE_TOGGLE_PREVIEW,
            livePreviewSettings: Strings.LIVE_DEV_SETTINGS,
            livePreviewConfigureModes: Strings.LIVE_PREVIEW_CONFIGURE_MODES,
            clickToPopout: Strings.LIVE_DEV_CLICK_POPOUT,
            openInChrome: Strings.LIVE_DEV_OPEN_CHROME,
            openInSafari: Strings.LIVE_DEV_OPEN_SAFARI,
            openInEdge: Strings.LIVE_DEV_OPEN_EDGE,
            openInFirefox: Strings.LIVE_DEV_OPEN_FIREFOX,
            clickToPinUnpin: Strings.LIVE_DEV_CLICK_TO_PIN_UNPIN
        };
        const PANEL_MIN_SIZE = 50;
        const INITIAL_PANEL_SIZE = document.body.clientWidth/2.5;
        $icon = $("#toolbar-go-live");
        $icon.click(_toggleVisibilityOnClick);
        $panel = $(Mustache.render(panelHTML, templateVars));
        $iframe = $panel.find("#panel-live-preview-frame");
        $pinUrlBtn = $panel.find("#pinURLButton");
        $reloadBtn = $panel.find("#reloadLivePreviewButton");
        $livePreviewPopBtn = $panel.find("#livePreviewPopoutButton");
        $chromeButton = $panel.find("#chromeButton");
        $safariButton = $panel.find("#safariButton");
        $edgeButton = $panel.find("#edgeButton");
        $firefoxButton = $panel.find("#firefoxButton");
        // ok i dont know enough CSS to do this without these Ballast/ this works for the limited dev time I have.
        $chromeButtonBallast = $panel.find("#chromeButtonBallast");
        $safariButtonBallast = $panel.find("#safariButtonBallast");
        $edgeButtonBallast = $panel.find("#edgeButtonBallast");
        $firefoxButtonBallast = $panel.find("#firefoxButtonBallast");
        $panelTitle = $panel.find("#panel-live-preview-title");
        $settingsIcon = $panel.find("#livePreviewSettingsBtn");
        $modeBtn = $panel.find("#livePreviewModeBtn");
        $previewBtn = $panel.find("#previewModeLivePreviewButton");

        // Markdown theme toggle — persist user choice
        MarkdownSync.setThemeToggleHandler((theme) => {
            PreferencesManager.set(PREF_MD_THEME, theme);
        });

        $panel.find(".live-preview-settings-banner-btn").on("click", ()=>{
            CommandManager.execute(Commands.FILE_LIVE_FILE_PREVIEW_SETTINGS);
            Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "settingsBtnBanner", "click");
        });
        $panel.find(".custom-server-banner-close-icon").on("click", ()=>{
            $panel.find(".live-preview-custom-banner").addClass("forced-hidden");
        });
        $iframe[0].onload = function () {
            $iframe.attr('srcdoc', null);
        };
        $panelTitle.on("click", ()=>{
            const fullPath = $panelTitle.attr("data-fullPath");
            const openPanes = MainViewManager.findInAllWorkingSets(fullPath);
            let paneToUse = MainViewManager.ACTIVE_PANE;
            if(openPanes.length) {
                paneToUse = openPanes[0].paneId;
            }
            FileViewController.openFileAndAddToWorkingSet(fullPath, paneToUse);
        });
        $chromeButton.on("click", ()=>{
            _popoutLivePreview("chrome");
        });
        $safariButton.on("click", ()=>{
            _popoutLivePreview("safari");
        });
        $edgeButton.on("click", ()=>{
            _popoutLivePreview("edge");
        });
        $firefoxButton.on("click", ()=>{
            _popoutLivePreview("firefox");
        });

        $modeBtn.on("click", _handleLPModeBtnClick);
        $previewBtn.on("click", _handlePreviewBtnClick);

        _showOpenBrowserIcons();
        $settingsIcon.click(()=>{
            CommandManager.execute(Commands.FILE_LIVE_FILE_PREVIEW_SETTINGS);
            Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "settingsBtn", "click");
        });

        const popoutSupported = Phoenix.isNativeApp
            || Phoenix.browser.desktop.isChromeBased || Phoenix.browser.desktop.isFirefox;
        if(!popoutSupported){
            // live preview can be popped out currently in only chrome based browsers. The cross domain iframe
            // that serves the live preview(phcode.live) is sandboxed to the tab in which phcode.dev resides.
            // all iframes in the tab can communicate between each other, but when you popout another tab, it forms
            // its own sandbox and firefox/safari prevents communication from iframe in one tab to another. chrome
            // doesn't seem to enforce this restriction. Since this is a core usecase, we will try to enable this
            // workflow whenever possible.
            $livePreviewPopBtn.addClass("forced-hidden");
        }

        panel = WorkspaceManager.createPluginPanel(LIVE_PREVIEW_PANEL_ID, $panel,
            PANEL_MIN_SIZE, $icon, INITIAL_PANEL_SIZE);

        WorkspaceManager.recomputeLayout(false);
        $pinUrlBtn.click(_togglePinUrl);
        $livePreviewPopBtn.click(_popoutLivePreview);
        $reloadBtn.click(()=>{
            if (_isMdviewrActive && urlPinned) {
                // When pinned, just re-send the pinned document's content
                MarkdownSync.resendContent();
                Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "reloadBtn", "click");
                return;
            }
            if (_isMdviewrActive) {
                MarkdownSync.reloadCurrentFile();
            }
            _loadPreview(true, true);
            Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "reloadBtn", "click");
        });

        // init the status overlay
        _initOverlay();
    }

    function _loadMdviewrPreview(previewDetails, force) {
        const currentDoc = DocumentManager.getCurrentDocument();
        if (!currentDoc) {
            return;
        }
        // Only render markdown files — skip binary, json, and other non-markdown files
        // (can happen when previewDetails is stale from async getPreviewDetails)
        if (!utils.isMarkdownFile(currentDoc.file.fullPath)) {
            return;
        }

        const mdFileURL = encodeURI(previewDetails.URL);
        const baseURL = mdFileURL.substring(0, mdFileURL.lastIndexOf("/") + 1);

        currentPreviewFile = previewDetails.fullPath;
        if (!urlPinned) {
            currentLivePreviewURL = mdFileURL;
        }
        let relativeOrFullPath = ProjectManager.makeProjectRelativeIfPossible(previewDetails.fullPath);
        relativeOrFullPath = Phoenix.app.getDisplayPath(relativeOrFullPath);
        _setTitle(relativeOrFullPath, currentPreviewFile, "");

        if (_isMdviewrActive) {
            if (urlPinned) {
                return;
            }
            // Mdviewr iframe already loaded, just update the sync for the new document
            MarkdownSync.activate(currentDoc, $iframe, baseURL);
            return;
        }

        // Reuse persistent md iframe if it exists (e.g. returning from HTML preview)
        if ($mdviewrIframe && $mdviewrIframe[0].parentNode) {
            // Hide the current HTML iframe and show the md iframe
            if ($iframe[0] !== $mdviewrIframe[0]) {
                $iframe.remove();
            }
            $mdviewrIframe.show();
            $iframe = $mdviewrIframe;
        } else if (panel.isVisible()) {
            // First time: create the md iframe (tighter sandbox for untrusted content)
            const mdviewrURL = StaticServer.getMdviewrURL();
            let newIframe = $(MDVIEWR_IFRAME_HTML);
            newIframe.insertAfter($iframe);
            $iframe.remove();
            $iframe = newIframe;
            $mdviewrIframe = newIframe;
            if (_isProjectPreviewTrusted()) {
                $iframe.attr('src', mdviewrURL);
            }
        }

        _isMdviewrActive = true;
        MarkdownSync.activate(currentDoc, $iframe, baseURL);
        // Apply persisted theme preference
        const savedTheme = PreferencesManager.get(PREF_MD_THEME) || "light";
        MarkdownSync.sendThemeOverride(savedTheme);
        // Sync preview mode and edit mode for reuse case where iframe is already ready
        _updateLPControlsForMdviewer();

        Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "render", "mdviewr");
    }

    async function _loadPreview(force, isReload) {
        // we wait till the first server ready event is received till we render anything. else a 404-page may
        // briefly flash on first load of phoenix as we try to load the page before the server is available.
        const isPreviewLoadable = panel.isVisible() || StaticServer.hasActiveLivePreviews();
        if(!isPreviewLoadable){
            return;
        }
        const thisGeneration = ++_loadGeneration;
        // panel-live-preview-title
        let previewDetails = await StaticServer.getPreviewDetails();
        if(thisGeneration !== _loadGeneration) {
            return; // A newer _loadPreview call has been made; this one is stale
        }
        if(urlPinned && !force) {
            return;
        }
        // When md viewer is pinned, block ALL preview loads — the previewDetails
        // would be for the current editor file, not the pinned file
        if(urlPinned && _isMdviewrActive) {
            return;
        }

        // Use mdviewr for markdown files (unless custom server is configured)
        if(previewDetails.isMarkdownFile && !previewDetails.isCustomServer && !previewDetails.isNoPreview) {
            _loadMdviewrPreview(previewDetails, force);
            return;
        }
        // Switching away from mdviewr to non-markdown preview
        // Hide the md iframe instead of destroying it so cache is preserved
        if(_isMdviewrActive) {
            MarkdownSync.deactivate();
            _isMdviewrActive = false;
            if ($mdviewrIframe) {
                $mdviewrIframe.hide();
            }
            _updateLPControlsForMdviewer();
        }
        let newSrc = encodeURI(previewDetails.URL);
        if($iframe.attr('src') === newSrc && !force){
            // we already have this url loaded in previews!
            return;
        }
        // we have to create a new iframe on every switch as we use cross domain iframes for phcode.live which
        // the browser sandboxes strictly and sometimes it wont allow a src change on our iframe causing live
        // preview breaks sporadically. to alleviate this, we create a new iframe every time.
        if(!urlPinned) {
            currentLivePreviewURL = newSrc;
            currentPreviewFile = previewDetails.fullPath;
        }
        if(isReload && previewDetails.isHTMLFile){
            LiveDevelopment.openLivePreview();
        }
        let relativeOrFullPath= ProjectManager.makeProjectRelativeIfPossible(currentPreviewFile);
        relativeOrFullPath = Phoenix.app.getDisplayPath(relativeOrFullPath);
        _setTitle(relativeOrFullPath, currentPreviewFile,
            previewDetails.isCustomServer ? currentLivePreviewURL : "");
        if(panel.isVisible()) {
            if(!customLivePreviewBannerShown && LivePreviewSettings.isUsingCustomServer()
                && previewDetails.isCustomServer) {
                customLivePreviewBannerShown = true;
                $panel.find(".live-preview-custom-banner").removeClass("forced-hidden");
                $panel.find(".live-preview-banner-message").text(
                    StringUtils.format(Strings.LIVE_PREVIEW_CUSTOM_SERVER_BANNER,
                        LivePreviewSettings.getCustomServeBaseURL())
                );
            }
            let newIframe = $(LIVE_PREVIEW_IFRAME_HTML);
            newIframe.insertAfter($iframe);
            // Don't remove the md iframe — it's persistent and already hidden
            if (!$mdviewrIframe || $iframe[0] !== $mdviewrIframe[0]) {
                $iframe.remove();
            }
            $iframe = newIframe;
            if(_isProjectPreviewTrusted()){
                $iframe.attr('src', currentLivePreviewURL);
                if(Phoenix.isTestWindow) {
                    window._livePreviewIntegTest.currentLivePreviewURL = currentLivePreviewURL;
                    window._livePreviewIntegTest.urlLoadCount++;
                }
            } else {
                $iframe.attr('srcdoc', _getTrustProjectPage());
            }
        }
        Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "render",
            utils.getExtension(previewDetails.fullPath));
        StaticServer.redirectAllTabs(currentLivePreviewURL, force);
        if(Phoenix.isTestWindow) {
            // for integ tests
            window._livePreviewIntegTest.redirectURL = currentLivePreviewURL;
            window._livePreviewIntegTest.redirectURLforce = force;
        }
    }

    async function _projectFileChanges(evt, changedFile) {
        if(_isMdviewrActive) {
            // MarkdownSync handles live content updates for markdown files
            return;
        }
        if(changedFile && changedFile.isFile && (utils.isPreviewableFile(changedFile.fullPath) ||
            utils.isServerRenderedFile(changedFile.fullPath))){
            // we are getting this change event somehow.
            // bug, investigate why we get this change event as a project file change.
            const previewDetails = await StaticServer.getPreviewDetails();
            let shouldReload = false;
            if(previewDetails.isCustomServer && !previewDetails.serverSupportsHotReload){
                shouldReload = true;
            }
            if(!previewDetails.isCustomServer && !(LiveDevelopment.isActive() && previewDetails.isHTMLFile)) {
                // We force reload live preview on save for all non html preview-able file or
                // if html file and live preview isnt active.
                shouldReload = true;
            }
            if(shouldReload) {
                _loadPreview(true);
            }
        }
    }

    function _openReadmeMDIfFirstTime() {
        if(!_isProjectReadmePreviewdOnce() && !Phoenix.isTestWindow){
            const readmePath = `${ProjectManager.getProjectRoot().fullPath}README.md`;
            const fileEntry = FileSystem.getFileForPath(readmePath);
            fileEntry.exists(function (err, exists) {
                if (!err && exists) {
                    _setPanelVisibility(true);
                    CommandManager.execute(Commands.CMD_ADD_TO_WORKINGSET_AND_OPEN, {fullPath: readmePath});
                    _setProjectReadmePreviewdOnce();
                }
            });
        }
    }

    function _switchToEditModeIfNeeded() {
        // Auto-switch mode based on project and user type
        const projectPath = ProjectManager.getProjectRoot().fullPath;
        const exploreProjectPath = ProjectManager.getExploreProjectPath();
        const isExploreProject = projectPath === exploreProjectPath;

        if (isExploreProject) {
            // Always use highlight mode for explore project
            LiveDevelopment.setMode(LiveDevelopment.CONSTANTS.LIVE_PREVIEW_MODE);
        } else if (isProEditUser) {
            // Pro users: auto-switch to edit mode on regular projects
            LiveDevelopment.setMode(LiveDevelopment.CONSTANTS.LIVE_EDIT_MODE);
        } else {
            // Non-pro users on regular projects: keep current mode (no change)
            LiveDevelopment.setMode(LiveDevelopment.CONSTANTS.LIVE_HIGHLIGHT_MODE);
        }
    }

    let startupFilesLoadHandled = false;
    /**
     * Send the current working set of markdown files to the mdviewr iframe.
     */
    function _syncWorkingSetToMdviewr() {
        if (!$mdviewrIframe) {
            return;
        }
        const mdIframeWindow = $mdviewrIframe[0].contentWindow;
        if (!mdIframeWindow) {
            return;
        }
        const workingSet = MainViewManager.getWorkingSet(MainViewManager.ALL_PANES);
        const mdPaths = workingSet
            .filter(file => utils.isMarkdownFile(file.fullPath))
            .map(file => file.fullPath);
        mdIframeWindow.postMessage({
            type: "MDVIEWR_WORKING_SET_CHANGED",
            paths: mdPaths
        }, "*");
    }

    async function _projectOpened() {
        // Deactivate mdviewr on project switch — keep iframe alive but clear cache
        if(_isMdviewrActive) {
            MarkdownSync.deactivate();
            _isMdviewrActive = false;
            _updateLPControlsForMdviewer();
        }
        if ($mdviewrIframe) {
            const mdIframeWindow = $mdviewrIframe[0].contentWindow;
            if (mdIframeWindow) {
                mdIframeWindow.postMessage({ type: "MDVIEWR_CLEAR_CACHE" }, "*");
            }
            $mdviewrIframe.hide();
        }
        _switchToEditModeIfNeeded();
        customLivePreviewBannerShown = false;
        $panel.find(".live-preview-custom-banner").addClass("forced-hidden");
        _openReadmeMDIfFirstTime();
        _customServerMetrics();
        if(!LiveDevelopment.isActive()
            && (panel.isVisible() || StaticServer.hasActiveLivePreviews())) {
            // we do this only once after project switch if live preview for a doc is not active.
            LiveDevelopment.openLivePreview();
        }
        if(urlPinned){
            _togglePinUrl();
        }
        // Ensure $iframe points to a visible HTML iframe, not the hidden md iframe
        if ($mdviewrIframe && $iframe[0] === $mdviewrIframe[0]) {
            let newIframe = $(LIVE_PREVIEW_IFRAME_HTML);
            $mdviewrIframe.after(newIframe);
            $iframe = newIframe;
        }
        $iframe.attr('src', StaticServer.getNoPreviewURL());
        if(!panelShownAtStartup && !isBrowser && ProjectManager.isStartupFilesLoaded()){
            // we dont do this in browser as the virtual server may not yet be started on app start
            // project open and a 404 page will briefly flash in the browser!
            // this mainly applies when phoenix is started with a preview file already open in previous exit
            startupFilesLoadHandled = true;
            const currentDocument = DocumentManager.getCurrentDocument();
            const currentFile = currentDocument? currentDocument.file : ProjectManager.getSelectedItem();
            const isPreviewable = currentFile ? utils.isPreviewableFile(currentFile.fullPath) : false;
            if(isPreviewable){
                _setPanelVisibility(true);
            }
        }
        if(!panel.isVisible()){
            return;
        }
        _loadPreview(true);
    }

    function _startupFilesLoaded() {
        if(startupFilesLoadHandled) {
            return;
            // we have to use this handled flag as there is no ordering of EVENT_AFTER_STARTUP_FILES_LOADED
            // and EVENT_PROJECT_OPEN. if _projectOpened has already shown the live preview panel when it saw that
            // ProjectManager.isStartupFilesLoaded() is true, we should not call project opened again at boot.
        }
        if(!panelShownAtStartup && !isBrowser && ProjectManager.isStartupFilesLoaded()){
            // we dont do this in browser as the virtual server may not yet be started on app start
            // project open and a 404 page will briefly flash in the browser!
            // this mainly applies when phoenix is started with a preview file already open in previous exit
            const currentDocument = DocumentManager.getCurrentDocument();
            const currentFile = currentDocument? currentDocument.file : ProjectManager.getSelectedItem();
            const isPreviewable = currentFile ? utils.isPreviewableFile(currentFile.fullPath) : false;
            if(isPreviewable){
                _setPanelVisibility(true);
                _loadPreview(true, true);
            }
        }
    }

    function _projectClosed() {
        if(urlPinned) {
            _togglePinUrl();
        }
        LiveDevelopment.closeLivePreview();
        if(customServerModalBar){
            customServerModalBar.close();
            customServerModalBar = null;
        }
    }

    function _activeDocChanged(event, focusedEditor, lostEditor) {
        // When md viewer is pinned, don't open HTML live preview — keep the md viewer visible
        if (_isMdviewrActive && urlPinned) {
            return;
        }

        if(!LivePreviewSettings.isUsingCustomServer() && !LiveDevelopment.isActive()
            && (panel.isVisible() || StaticServer.hasActiveLivePreviews())) {
            // we do this only once after project switch if live preview for a doc is not active.
            LiveDevelopment.openLivePreview();
        }

        // we hide the overlay when there's no editor or its a non-previewable file
        if (!focusedEditor || !focusedEditor.document) {
            _hideOverlay();
            return;
        }

        const filePath = focusedEditor.document.file.fullPath;
        const isPreviewable = utils.isPreviewableFile(filePath) || utils.isServerRenderedFile(filePath);
        const customServeURL = LivePreviewSettings.isUsingCustomServer() &&
            LivePreviewSettings.getCustomServerConfig(filePath);

        if (!isPreviewable && !customServeURL) {
            _hideOverlay();
        }
    }

    /**
     * EVENT_OPEN_PREVIEW_URL triggers this once live preview infrastructure is instrumented and ready to accept live
     * preview connections from browsers. So, if we have loaded an earlier live preview, that is most likely not
     * instrumented code and just plain html for the previewed file. We force load the live preview again here to
     * load the instrumented live preview code.
     * @param _event
     * @param previewDetails
     * @return {Promise<void>}
     * @private
     */
    async function _openLivePreviewURL(_event, previewDetails) {
        if(LivePreviewSettings.isUsingCustomServer()){
            _hideOverlay();
            return;
        }
        if (_isMdviewrActive && urlPinned) {
            return;
        }
        _loadPreview(true);
        const currentPreviewDetails = await StaticServer.getPreviewDetails();
        if(currentPreviewDetails.isHTMLFile && currentPreviewDetails.fullPath !== previewDetails.fullPath){
            console.error("Live preview URLs differ between phoenix live preview extension and core live preview",
                currentPreviewDetails, previewDetails);
        }

        const status = MultiBrowserLiveDev.status;
        if (status === MultiBrowserLiveDev.STATUS_CONNECTING) {
            _handleOverlay(Strings.LIVE_DEV_STATUS_TIP_PROGRESS1, status);
        } else if (status === MultiBrowserLiveDev.STATUS_SYNC_ERROR) {
            _handleOverlay(Strings.LIVE_DEV_STATUS_TIP_SYNC_ERROR, status);
        }
    }

    async function _currentFileChanged(_event, changedFile) {
        if(!changedFile || !changedFile.fullPath || !ProjectManager.isStartupFilesLoaded()){
            return;
        }
        const fullPath = changedFile.fullPath;
        if(changedFile && _shouldShowCustomServerBar(fullPath)){
            _showCustomServerBar(fullPath);
        }
        const shouldUseInbuiltPreview = utils.isMarkdownFile(fullPath) || utils.isSVG(fullPath);
        const customServeURL = LivePreviewSettings.isUsingCustomServer() &&
            LivePreviewSettings.getCustomServerConfig(fullPath);
        if(urlPinned || (LivePreviewSettings.isUsingCustomServer() && !customServeURL && !shouldUseInbuiltPreview)){
            return;
        }
        // If we are using a custom server URL, we need to handle the live preview carefully:
        // - If the user has not clicked on a previewable file from the custom server URL,
        //   we should always show the base server URL. This is because some projects, like React,
        //   do not have an HTML file and only contain JSX/render files. In these cases, we should show the live preview
        // - However, if the user is already previewing a file from the custom server (e.g., customBaseURL/some.html),
        //   we should not switch back to the base URL when they click on another file (e.g., a JS file).
        //   This is because the user might be editing a related file of the custom-served page.
        // - Therefore, we only switch to the base URL if the current preview has nothing to do with the custom server
        //   URL for a better user experience.
        const shouldSwitchCustomServer = customServeURL && currentLivePreviewURL !== customServeURL &&
            (!currentLivePreviewURL || !currentLivePreviewURL.startsWith(customServeURL));
        if(changedFile && (utils.isPreviewableFile(fullPath) ||
            utils.isServerRenderedFile(fullPath) || shouldSwitchCustomServer)){
            _loadPreview();
            if(!panelShownAtStartup && ProjectManager.isStartupFilesLoaded()){
                let previewDetails = await StaticServer.getPreviewDetails();
                if(previewDetails && !previewDetails.isNoPreview) {
                    _setPanelVisibility(true);
                    _loadPreview();
                }
            }
        }
    }

    function _showSettingsDialog() {
        return new Promise(resolve=>{
            LivePreviewSettings.showSettingsDialog()
                .then(()=>{
                    _loadPreview();
                    resolve();
                });
        });
    }

    function _customServerMetrics() {
        if(LivePreviewSettings.isUsingCustomServer()){
            Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "customServ", "yes");
            Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "framework",
                LivePreviewSettings.getCustomServerFramework() || "unknown");
            if(LivePreviewSettings.serverSupportsHotReload()) {
                Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "hotReload", "yes");
            }
        }
    }

    function _showCustomServerBannerIfNeeded() {
        const editor = EditorManager.getActiveEditor();
        if(!editor || !_shouldShowCustomServerBar(editor.document.file.fullPath)){
            return;
        }
        _showCustomServerBar(editor.document.file.fullPath);
    }

    function _shouldShowCustomServerBar(fullPath) {
        const isBannerAck = StateManager.get(STATE_CUSTOM_SERVER_BANNER_ACK, StateManager.PROJECT_CONTEXT);
        let panelVisible = panel && panel.isVisible();
        if(isBannerAck || LivePreviewSettings.isUsingCustomServer() || !panelVisible){
            return false;
        }
        return utils.isServerRenderedFile(fullPath);
    }

    function _showCustomServerBar(fullFilePath) {
        if(customServerModalBar){
            $(".custom-banner-setup-server-text-message").html(
                StringUtils.format(Strings.LIVE_DEV_SETTINGS_BANNER, path.extname(fullFilePath))
            );
            return;
        }
        // Show the search bar
        const searchBarHTML =`<div style="display: flex;justify-content: end;align-items: baseline;">
            <div style="margin-right: 5px;" class="custom-banner-setup-server-text-message">
                ${StringUtils.format(Strings.LIVE_DEV_SETTINGS_BANNER, path.extname(fullFilePath))}
            </div>
            <button class="btn btn-mini live-preview-settings" style="margin-right: 5px;">
                ${Strings.LIVE_DEV_SETTINGS}
            </button>
            <div class="close-icon" style="align-self: center;margin-left: 10px;margin-right: 5px;cursor: pointer;"
                title="${Strings.CLOSE}">
                <i class="fa-solid fa-xmark"></i>
            </div>
        </div>`;
        customServerModalBar = new ModalBar(searchBarHTML);
        const $modal = customServerModalBar.getRoot();
        $modal.find(".live-preview-settings")
            .click(()=>{
                _showSettingsDialog()
                    .then(()=>{
                        if(LivePreviewSettings.isUsingCustomServer()){
                            customServerModalBar && customServerModalBar.close();
                            customServerModalBar = null;
                            StateManager.set(STATE_CUSTOM_SERVER_BANNER_ACK, true, StateManager.PROJECT_CONTEXT);
                        }
                    });
            });
        $modal.find(".close-icon").click(()=>{
            customServerModalBar && customServerModalBar.close();
            customServerModalBar = null;
            StateManager.set(STATE_CUSTOM_SERVER_BANNER_ACK, true, StateManager.PROJECT_CONTEXT);
        });
    }

    function _registerHandlers() {
        // when clicked anywhere on the page we want to close the dropdown
        $("html").on("click", function (e) {
            if ($(e.target).closest("#livePreviewModeBtn").length) { return; }
            _closeDropdown();
        });

        $(document).on("click", "#livePreviewModeBtn", function (e) {
            _handleLPModeBtnClick(e);
        });

        $(document).on("keydown", function (e) {
            if (e.key === "F8") {
                e.preventDefault();
                _handlePreviewBtnClick();
            }
        });
    }

    AppInit.appReady(function () {
        if(Phoenix.isSpecRunnerWindow){
            return;
        }
        panelShownAtStartup = !LivePreviewSettings.shouldShowLivePreviewAtStartup();
        Metrics.countEvent(Metrics.EVENT_TYPE.LIVE_PREVIEW, "atStart",
            LivePreviewSettings.shouldShowLivePreviewAtStartup() ? "show" : "hide");
        _createExtensionPanel();
        StaticServer.init();
        LiveDevServerManager.registerServer({ create: _createStaticServer }, 5);
        ProjectManager.on(ProjectManager.EVENT_PROJECT_FILE_CHANGED, _projectFileChanges);
        ProjectManager.on(ProjectManager.EVENT_PROJECT_OPEN, _projectOpened);
        ProjectManager.on(ProjectManager.EVENT_PROJECT_CLOSE, _projectClosed);
        EditorManager.on("activeEditorChange", _activeDocChanged);
        ProjectManager.on(ProjectManager.EVENT_AFTER_STARTUP_FILES_LOADED, _startupFilesLoaded);
        let fileChangeListenerStartDelay = 0;
        if(Phoenix.isNativeApp && Phoenix.platform === "mac") {
            // in mac, if we do the `open with Phoenix Code` from finder, then, the open with events come as events
            // after app start. This causes a problem where if we open a txt file with open with, and an html file was
            // open previously, then currentFileChange listener will see the html file at first and open the live
            // preview panel, and immediately, the txt file event will be sent by os resulting in a no preview page.
            // we should not show a no preview page for opening txt / non-previewable files. So, we dont attach the
            // change listener in macos for a second to give some time for the os event to reach.
            fileChangeListenerStartDelay = 600;
        }
        // Sync working set changes to md iframe for cache management
        MainViewManager.on("workingSetAdd", _syncWorkingSetToMdviewr);
        MainViewManager.on("workingSetAddList", _syncWorkingSetToMdviewr);
        MainViewManager.on("workingSetRemove", _syncWorkingSetToMdviewr);
        MainViewManager.on("workingSetRemoveList", _syncWorkingSetToMdviewr);

        setTimeout(()=>{
            MainViewManager.on("currentFileChange", _currentFileChanged);
            if(Phoenix.isNativeApp && Phoenix.platform === "mac" && MainViewManager.getCurrentlyViewedFile()) {
                _currentFileChanged(null, MainViewManager.getCurrentlyViewedFile());
            }
        }, fileChangeListenerStartDelay);
        CommandManager.register(Strings.CMD_LIVE_FILE_PREVIEW,  Commands.FILE_LIVE_FILE_PREVIEW, function () {
            _toggleVisibilityOnClick();
        });
        CommandManager.register(Strings.CMD_LIVE_FILE_PREVIEW_SETTINGS,
            Commands.FILE_LIVE_FILE_PREVIEW_SETTINGS, _showSettingsDialog);
        CommandManager.register(Strings.CMD_RELOAD_LIVE_PREVIEW, Commands.CMD_RELOAD_LIVE_PREVIEW, function () {
            _loadPreview(true, true);
        });
        let fileMenu = Menus.getMenu(Menus.AppMenuBar.FILE_MENU);
        fileMenu.addMenuItem(Commands.FILE_LIVE_FILE_PREVIEW, "", Menus.AFTER, Commands.FILE_EXTENSION_MANAGER);
        fileMenu.addMenuItem(Commands.CMD_RELOAD_LIVE_PREVIEW, "",
            Menus.AFTER, Commands.FILE_LIVE_FILE_PREVIEW);
        fileMenu.addMenuItem(Commands.FILE_LIVE_FILE_PREVIEW_SETTINGS, "",
            Menus.AFTER, Commands.CMD_RELOAD_LIVE_PREVIEW);
        fileMenu.addMenuDivider(Menus.BEFORE, Commands.FILE_LIVE_FILE_PREVIEW);

        _registerHandlers();
        // init live preview mode from saved preferences
        _initializeMode();
        // listen for pref changes
        PreferencesManager.on("change", "livePreviewMode", function () {
            _initializeMode();
        });

        // Handle element highlight & ruler lines preference changes
        PreferencesManager.on("change", PREFERENCE_PROJECT_ELEMENT_HIGHLIGHT, function() {
            LiveDevelopment.updateElementHighlightConfig();
        });
        PreferencesManager.on("change", PREFERENCE_SHOW_RULER_LINES, function() {
            LiveDevelopment.updateRulerLinesConfig();
        });
        PreferencesManager.on("change", PREFERENCE_LIVE_PREVIEW_SYNC, function() {
            LiveDevelopment.updateSyncConfig();
        });

        // Initialize element highlight, ruler lines, and sync config on startup
        LiveDevelopment.updateElementHighlightConfig();
        LiveDevelopment.updateRulerLinesConfig();
        LiveDevelopment.updateSyncConfig();

        LiveDevelopment.openLivePreview();
        LiveDevelopment.on(LiveDevelopment.EVENT_OPEN_PREVIEW_URL, _openLivePreviewURL);
        LiveDevelopment.on(LiveDevelopment.EVENT_LIVE_PREVIEW_RELOAD, ()=>{
            // Usually, this event is listened by live preview iframes/tabs and they initiate a location.reload.
            // But in firefox, the embedded iframe will throw a 404 when we try to reload from within the iframe as
            // in firefox security posture, the third party live preview iframe phcode.live itself cannot activate
            // the service worker. So we have to reload the iframe from its parent- ie. phcode.dev. This is not
            // required in chrome, but we just keep it just for all platforms behaving the same.
            _loadPreview(true);
        });

        MultiBrowserLiveDev.on(MultiBrowserLiveDev.EVENT_STATUS_CHANGE, function(event, status) {
            if(LivePreviewSettings.isUsingCustomServer()){
                _hideOverlay();
            } else if (status === MultiBrowserLiveDev.STATUS_CONNECTING) {
                _handleOverlay(Strings.LIVE_DEV_STATUS_TIP_PROGRESS1, status);
            } else if (status === MultiBrowserLiveDev.STATUS_SYNC_ERROR) {
                _handleOverlay(Strings.LIVE_DEV_STATUS_TIP_SYNC_ERROR, status);
            } else {
                _hideOverlay();
            }
        });

        function refreshPreview() {
            StaticServer.getPreviewDetails().then((previewDetails)=>{
                _openReadmeMDIfFirstTime();
                if(!LivePreviewSettings.shouldShowLivePreviewAtStartup()){
                    return;
                }
                // we show the live preview
                // in browser, we always show the live preview on startup even if its a no preview page
                // Eg. in mac safari browser we show mac doesnt support live preview page in live preview.
                if(previewDetails.URL && (isBrowser || !previewDetails.isNoPreview) && !panelShownAtStartup){
                    // only show if there is some file to preview and not the default no-preview preview on startup
                    _setPanelVisibility(true);
                }
                // in browsers, the static server is not reset on every call to open live preview, so its safe to reload
                // we need to reload once as
                const shouldReload = !Phoenix.isNativeApp;
                _loadPreview(true, shouldReload);
            });
        }

        let customServerRefreshedOnce = false;
        StaticServer.on(StaticServer.EVENT_SERVER_READY, function (_evt, event) {
            if(LivePreviewSettings.isUsingCustomServer() && customServerRefreshedOnce){
                return;
            }
            customServerRefreshedOnce = true;
            refreshPreview();
        });
        function _handleNewCustomServer() {
            customLivePreviewBannerShown = false;
            refreshPreview();
            _customServerMetrics();
        }

        LivePreviewSettings.on(LivePreviewSettings.EVENT_SERVER_CHANGED, _handleNewCustomServer);
        LivePreviewSettings.on(LivePreviewSettings.EVENT_CUSTOM_SERVER_ENABLED_CHANGED, (_evt, enabled)=>{
            if(!enabled) {
                $panel.find(".live-preview-custom-banner").addClass("forced-hidden");
            } else {
                _handleNewCustomServer();
            }
        });

        let consecutiveEmptyClientsCount = 0;
        setInterval(()=>{
            if(!StaticServer.hasActiveLivePreviews()){
                consecutiveEmptyClientsCount ++;
            } else {
                consecutiveEmptyClientsCount = 0;
            }
            if(consecutiveEmptyClientsCount > 5){
                _startOrStopLivePreviewIfRequired();
            }
        }, 1000);
        // Handle edit mode requests from mdviewer iframe — gate on entitlement
        MarkdownSync.setEditModeRequestHandler(function () {
            if (isProEditUser) {
                // Entitled — send edit mode to iframe
                if ($iframe && $iframe[0] && $iframe[0].contentWindow) {
                    $iframe[0].contentWindow.postMessage(
                        { type: "MDVIEWR_SET_EDIT_MODE", editMode: true }, "*");
                }
            } else {
                // Not entitled — show upsell dialog
                const buttonGetProText = StringUtils.format(Strings.PROMO_UPGRADE_APP_UPSELL_BUTTON,
                    brackets.config.main_pro_plan_short);
                const buttons = [
                    { className: Dialogs.DIALOG_BTN_CLASS_NORMAL, id: Dialogs.DIALOG_BTN_CANCEL,
                        text: Strings.GET_PRO_NOT_NOW },
                    { className: Dialogs.DIALOG_BTN_CLASS_PRIMARY, id: "get_pro",
                        text: buttonGetProText }
                ];
                Metrics.countEvent(Metrics.EVENT_TYPE.LP_EDIT, "mdEditUpsell", "show");
                Dialogs.showModalDialog(Dialogs.DIALOG_ID_INFO,
                    Strings.AVAILABLE_IN_PRO_TITLE,
                    Strings.MD_EDIT_UPSELL_MESSAGE, buttons)
                    .done(function (id) {
                        Metrics.countEvent(Metrics.EVENT_TYPE.LP_EDIT, "mdEditUpsell", id);
                        if (id === "get_pro") {
                            Phoenix.app.openURLInDefaultBrowser(brackets.config.purchase_url);
                        }
                    });
            }
        });

        // When iframe first loads, send initial edit mode based on entitlement
        MarkdownSync.setIframeReadyHandler(function () {
            _updateLPControlsForMdviewer();
            // Pro users default to edit mode on first load
            if (isProEditUser) {
                MarkdownSync.setEditMode(true);
            }
        });

        _projectOpened();
        if(!Phoenix.isSpecRunnerWindow){
            _entitlementsChanged();
            // in community edition EntitlementsManager may be null
            KernalModeTrust.EntitlementsManager && KernalModeTrust.EntitlementsManager.on(
                KernalModeTrust.EntitlementsManager.EVENT_ENTITLEMENTS_CHANGED,
                _entitlementsChanged
            );
        }
    });

    // private API to be used inside phoenix codebase only
    exports.LIVE_PREVIEW_PANEL_ID = LIVE_PREVIEW_PANEL_ID;
});