import { callPopup, eventSource, event_types, saveSettings, saveSettingsDebounced, getRequestHeaders, substituteParams, renderTemplate } from "../script.js";
import { isSubsetOf } from "./utils.js";
export {
    getContext,
    getApiUrl,
    loadExtensionSettings,
    runGenerationInterceptors,
    doExtrasFetch,
    modules,
    extension_settings,
    ModuleWorkerWrapper,
};

export let extensionNames = [];
let manifests = {};
const defaultUrl = "http://localhost:5100";

let saveMetadataTimeout = null;

export function saveMetadataDebounced() {
    const context = getContext();
    const groupId = context.groupId;
    const characterId = context.characterId;

    if (saveMetadataTimeout) {
        console.debug('Clearing save metadata timeout');
        clearTimeout(saveMetadataTimeout);
    }

    saveMetadataTimeout = setTimeout(async () => {
        const newContext = getContext();

        if (groupId !== newContext.groupId) {
            console.warn('Group changed, not saving metadata');
            return;
        }

        if (characterId !== newContext.characterId) {
            console.warn('Character changed, not saving metadata');
            return;
        }

        console.debug('Saving metadata...');
        newContext.saveMetadata();
        console.debug('Saved metadata...');
    }, 1000);
}

export const extensionsHandlebars = Handlebars.create();

/**
 * Provides an ability for extensions to render HTML templates.
 * Templates sanitation and localization is forced.
 * @param {string} extensionName Extension name
 * @param {string} templateId Template ID
 * @param {object} templateData Additional data to pass to the template
 * @returns {string} Rendered HTML
 */
export function renderExtensionTemplate(extensionName, templateId, templateData = {}, sanitize = true, localize = true) {
    return renderTemplate(`scripts/extensions/${extensionName}/${templateId}.html`, templateData, sanitize, localize, true);
}

/**
 * Registers a Handlebars helper for use in extensions.
 * @param {string} name Handlebars helper name
 * @param {function} helper Handlebars helper function
 */
export function registerExtensionHelper(name, helper) {
    extensionsHandlebars.registerHelper(name, helper);
}

/**
 * Applies handlebars extension helpers to a message.
 * @param {number} messageId Message index in the chat.
 */
export function processExtensionHelpers(messageId) {
    const context = getContext();
    const message = context.chat[messageId];

    if (!message?.mes || typeof message.mes !== 'string') {
        return;
    }

    // Don't waste time if there are no mustaches
    if (!substituteParams(message.mes).includes('{{')) {
        return;
    }

    try {
        const template = extensionsHandlebars.compile(substituteParams(message.mes), { noEscape: true });
        message.mes = template({});
    } catch {
        // Ignore
    }
}

// Disables parallel updates
class ModuleWorkerWrapper {
    constructor(callback) {
        this.isBusy = false;
        this.callback = callback;
    }

    // Called by the extension
    async update() {
        // Don't touch me I'm busy...
        if (this.isBusy) {
            return;
        }

        // I'm free. Let's update!
        try {
            this.isBusy = true;
            await this.callback();
        }
        finally {
            this.isBusy = false;
        }
    }
}

const extension_settings = {
    apiUrl: defaultUrl,
    apiKey: '',
    autoConnect: false,
    disabledExtensions: [],
    expressionOverrides: [],
    memory: {},
    note: {
        default: '',
        chara: [],
        wiAddition: [],
    },
    caption: {
        refine_mode: false,
    },
    expressions: {
        /** @type {string[]} */
        custom: [],
    },
    dice: {},
    regex: [],
    tts: {},
    sd: {
        prompts: {},
        character_prompts: {},
    },
    chromadb: {},
    translate: {},
    objective: {},
    quickReply: {},
    randomizer: {
        controls: [],
        fluctuation: 0.1,
        enabled: false,
    },
    speech_recognition: {},
    rvc: {},
    hypebot: {},
    vectors: {},
};

let modules = [];
let activeExtensions = new Set();

const getContext = () => window['SillyTavern'].getContext();
const getApiUrl = () => extension_settings.apiUrl;
let connectedToApi = false;

function showHideExtensionsMenu() {
    // Get the number of menu items that are not hidden
    const hasMenuItems = $('#extensionsMenu').children().filter((_, child) => $(child).css('display') !== 'none').length > 0;

    // We have menu items, so we can stop checking
    if (hasMenuItems) {
        clearInterval(menuInterval);
    }

    // Show or hide the menu button
    $('#extensionsMenuButton').toggle(hasMenuItems);
}

// Periodically check for new extensions
const menuInterval = setInterval(showHideExtensionsMenu, 1000);

async function doExtrasFetch(endpoint, args) {
    if (!args) {
        args = {}
    }

    if (!args.method) {
        Object.assign(args, { method: 'GET' });
    }

    if (!args.headers) {
        args.headers = {}
    }
    Object.assign(args.headers, {
        'Authorization': `Bearer ${extension_settings.apiKey}`,
    });

    const response = await fetch(endpoint, args);
    return response;
}

async function discoverExtensions() {
    try {
        const response = await fetch('/api/extensions/discover');

        if (response.ok) {
            const extensions = await response.json();
            return extensions;
        }
        else {
            return [];
        }
    }
    catch (err) {
        console.error(err);
        return [];
    }
}

function onDisableExtensionClick() {
    const name = $(this).data('name');
    disableExtension(name);
}

function onEnableExtensionClick() {
    const name = $(this).data('name');
    enableExtension(name);
}

async function enableExtension(name) {
    extension_settings.disabledExtensions = extension_settings.disabledExtensions.filter(x => x !== name);
    await saveSettings();
    location.reload();
}

async function disableExtension(name) {
    extension_settings.disabledExtensions.push(name);
    await saveSettings();
    location.reload();
}

async function getManifests(names) {
    const obj = {};
    const promises = [];

    for (const name of names) {
        const promise = new Promise((resolve, reject) => {
            fetch(`/scripts/extensions/${name}/manifest.json`).then(async response => {
                if (response.ok) {
                    const json = await response.json();
                    obj[name] = json;
                    resolve();
                } else {
                    reject();
                }
            }).catch(err => {
                reject();
                console.log('Could not load manifest.json for ' + name, err);
            });
        });

        promises.push(promise);
    }

    await Promise.allSettled(promises);
    return obj;
}

async function activateExtensions() {
    const extensions = Object.entries(manifests).sort((a, b) => a[1].loading_order - b[1].loading_order);
    const promises = [];

    for (let entry of extensions) {
        const name = entry[0];
        const manifest = entry[1];
        const elementExists = document.getElementById(name) !== null;

        if (elementExists || activeExtensions.has(name)) {
            continue;
        }

        // all required modules are active (offline extensions require none)
        if (isSubsetOf(modules, manifest.requires)) {
            try {
                const isDisabled = extension_settings.disabledExtensions.includes(name);
                const li = document.createElement('li');

                if (!isDisabled) {
                    const promise = Promise.all([addExtensionScript(name, manifest), addExtensionStyle(name, manifest)]);
                    promise
                        .then(() => activeExtensions.add(name))
                        .catch(err => console.log('Could not activate extension: ' + name, err));
                    promises.push(promise);
                }
                else {
                    li.classList.add('disabled');
                }

                li.id = name;
                li.innerText = manifest.display_name;

                $('#extensions_list').append(li);
            }
            catch (error) {
                console.error(`Could not activate extension: ${name}`);
                console.error(error);
            }
        }
    }

    await Promise.allSettled(promises);
}

async function connectClickHandler() {
    const baseUrl = $("#extensions_url").val();
    extension_settings.apiUrl = String(baseUrl);
    const testApiKey = $("#extensions_api_key").val();
    extension_settings.apiKey = String(testApiKey);
    saveSettingsDebounced();
    await connectToApi(baseUrl);
}

function autoConnectInputHandler() {
    const value = $(this).prop('checked');
    extension_settings.autoConnect = !!value;

    if (value && !connectedToApi) {
        $("#extensions_connect").trigger('click');
    }

    saveSettingsDebounced();
}

function addExtensionsButtonAndMenu() {
    const buttonHTML =
        `<div id="extensionsMenuButton" style="display: none;" class="fa-solid fa-magic-wand-sparkles" title="Extras Extensions" /></div>`;
    const extensionsMenuHTML = `<div id="extensionsMenu" class="options-content" style="display: none;"></div>`;

    $(document.body).append(extensionsMenuHTML);

    $('#send_but_sheld').prepend(buttonHTML);

    const button = $('#extensionsMenuButton');
    const dropdown = $('#extensionsMenu');
    //dropdown.hide();

    let popper = Popper.createPopper(button.get(0), dropdown.get(0), {
        placement: 'top-end',
    });

    $(button).on('click', function () {
        popper.update()
        dropdown.fadeIn(250);
    });

    $("html").on('touchstart mousedown', function (e) {
        let clickTarget = $(e.target);
        if (dropdown.is(':visible')
            && clickTarget.closest(button).length == 0
            && clickTarget.closest(dropdown).length == 0) {
            $(dropdown).fadeOut(250);
        }
    });
}

/*     $(document).on('click', function (e) {
        const target = $(e.target);
        if (target.is(dropdown)) return;
        if (target.is(button) && dropdown.is(':hidden')) {
            dropdown.toggle(200);
            popper.update();
        }
        if (target !== dropdown &&
            target !== button &&
            dropdown.is(":visible")) {
            dropdown.hide(200);
        }
    });
} */

async function connectToApi(baseUrl) {
    if (!baseUrl) {
        return;
    }

    const url = new URL(baseUrl);
    url.pathname = '/api/modules';

    try {
        const getExtensionsResult = await doExtrasFetch(url);

        if (getExtensionsResult.ok) {
            const data = await getExtensionsResult.json();
            modules = data.modules;
            await activateExtensions();
            eventSource.emit(event_types.EXTRAS_CONNECTED, modules);
        }

        updateStatus(getExtensionsResult.ok);
    }
    catch {
        updateStatus(false);
    }
}

function updateStatus(success) {
    connectedToApi = success;
    const _text = success ? 'Connected to API' : 'Could not connect to API';
    const _class = success ? 'success' : 'failure';
    $('#extensions_status').text(_text);
    $('#extensions_status').attr('class', _class);
}

function addExtensionStyle(name, manifest) {
    if (manifest.css) {
        return new Promise((resolve, reject) => {
            const url = `/scripts/extensions/${name}/${manifest.css}`;

            if ($(`link[id="${name}"]`).length === 0) {
                const link = document.createElement('link');
                link.id = name;
                link.rel = "stylesheet";
                link.type = "text/css";
                link.href = url;
                link.onload = function () {
                    resolve();
                }
                link.onerror = function (e) {
                    reject(e);
                }
                document.head.appendChild(link);
            }
        });
    }

    return Promise.resolve();
}

function addExtensionScript(name, manifest) {
    if (manifest.js) {
        return new Promise((resolve, reject) => {
            const url = `/scripts/extensions/${name}/${manifest.js}`;
            let ready = false;

            if ($(`script[id="${name}"]`).length === 0) {
                const script = document.createElement('script');
                script.id = name;
                script.type = 'module';
                script.src = url;
                script.async = true;
                script.onerror = function (err) {
                    reject(err, script);
                };
                script.onload = script.onreadystatechange = function () {
                    // console.log(this.readyState); // uncomment this line to see which ready states are called.
                    if (!ready && (!this.readyState || this.readyState == 'complete')) {
                        ready = true;
                        resolve();
                    }
                };
                document.body.appendChild(script);
            }
        });
    }

    return Promise.resolve();
}



/**
 * Generates HTML string for displaying an extension in the UI.
 *
 * @param {string} name - The name of the extension.
 * @param {object} manifest - The manifest of the extension.
 * @param {boolean} isActive - Whether the extension is active or not.
 * @param {boolean} isDisabled - Whether the extension is disabled or not.
 * @param {boolean} isExternal - Whether the extension is external or not.
 * @param {string} checkboxClass - The class for the checkbox HTML element.
 * @return {string} - The HTML string that represents the extension.
 */
async function generateExtensionHtml(name, manifest, isActive, isDisabled, isExternal, checkboxClass) {
    const displayName = manifest.display_name;
    let displayVersion = manifest.version ? ` v${manifest.version}` : "";
    let isUpToDate = true;
    let updateButton = '';
    let originHtml = '';
    if (isExternal) {
        let data = await getExtensionVersion(name.replace('third-party', ''));
        let branch = data.currentBranchName;
        let commitHash = data.currentCommitHash;
        let origin = data.remoteUrl
        isUpToDate = data.isUpToDate;
        displayVersion = ` (${branch}-${commitHash.substring(0, 7)})`;
        updateButton = isUpToDate ?
            `<span class="update-button"><button class="btn_update menu_button" data-name="${name.replace('third-party', '')}" title="Up to date"><i class="fa-solid fa-code-commit"></i></button></span>` :
            `<span class="update-button"><button class="btn_update menu_button" data-name="${name.replace('third-party', '')}" title="Update available"><i class="fa-solid fa-download"></i></button></span>`;
        originHtml = `<a href="${origin}" target="_blank" rel="noopener noreferrer">`;
    }

    let toggleElement = isActive || isDisabled ?
        `<input type="checkbox" title="Click to toggle" data-name="${name}" class="${isActive ? 'toggle_disable' : 'toggle_enable'} ${checkboxClass}" ${isActive ? 'checked' : ''}>` :
        `<input type="checkbox" title="Cannot enable extension" data-name="${name}" class="extension_missing ${checkboxClass}" disabled>`;

    let deleteButton = isExternal ? `<span class="delete-button"><button class="btn_delete menu_button" data-name="${name.replace('third-party', '')}" title="Delete"><i class="fa-solid fa-trash-can"></i></button></span>` : '';

    // if external, wrap the name in a link to the repo

    let extensionHtml = `<hr>
        <h4>
            ${updateButton}
            ${deleteButton}
            ${originHtml}
            <span class="${isActive ? "extension_enabled" : isDisabled ? "extension_disabled" : "extension_missing"}">
                ${DOMPurify.sanitize(displayName)}${displayVersion}
            </span>
            ${isExternal ? '</a>' : ''}

            <span style="float:right;">${toggleElement}</span>
        </h4>`;

    if (isActive && Array.isArray(manifest.optional)) {
        const optional = new Set(manifest.optional);
        modules.forEach(x => optional.delete(x));
        if (optional.size > 0) {
            const optionalString = DOMPurify.sanitize([...optional].join(', '));
            extensionHtml += `<p>Optional modules: <span class="optional">${optionalString}</span></p>`;
        }
    } else if (!isDisabled) { // Neither active nor disabled
        const requirements = new Set(manifest.requires);
        modules.forEach(x => requirements.delete(x));
        const requirementsString = DOMPurify.sanitize([...requirements].join(', '));
        extensionHtml += `<p>Missing modules: <span class="failure">${requirementsString}</span></p>`;
    }

    return extensionHtml;
}

/**
 * Gets extension data and generates the corresponding HTML for displaying the extension.
 *
 * @param {Array} extension - An array where the first element is the extension name and the second element is the extension manifest.
 * @return {Promise<object>} - An object with 'isExternal' indicating whether the extension is external, and 'extensionHtml' for the extension's HTML string.
 */
async function getExtensionData(extension) {
    const name = extension[0];
    const manifest = extension[1];
    const isActive = activeExtensions.has(name);
    const isDisabled = extension_settings.disabledExtensions.includes(name);
    const isExternal = name.startsWith('third-party');

    const checkboxClass = isDisabled ? "checkbox_disabled" : "";

    const extensionHtml = await generateExtensionHtml(name, manifest, isActive, isDisabled, isExternal, checkboxClass);

    return { isExternal, extensionHtml };
}


/**
 * Gets the module information to be displayed.
 *
 * @return {string} - The HTML string for the module information.
 */
function getModuleInformation() {
    let moduleInfo = modules.length ? `<p>${DOMPurify.sanitize(modules.join(', '))}</p>` : '<p class="failure">Not connected to the API!</p>';
    return `
        <h3>Modules provided by your Extensions API:</h3>
        ${moduleInfo}
    `;
}

/**
 * Generates the HTML strings for all extensions and displays them in a popup.
 */
async function showExtensionsDetails() {
    let htmlDefault = '<h3>Default Extensions:</h3>';
    let htmlExternal = '<h3>External Extensions:</h3>';

    const extensions = Object.entries(manifests).sort((a, b) => a[1].loading_order - b[1].loading_order);

    for (const extension of extensions) {
        const { isExternal, extensionHtml } = await getExtensionData(extension);
        if (isExternal) {
            htmlExternal += extensionHtml;
        } else {
            htmlDefault += extensionHtml;
        }
    }

    const html = `
        ${getModuleInformation()}
        ${htmlDefault}
        ${htmlExternal}
    `;
    callPopup(`<div class="extensions_info">${html}</div>`, 'text');
}


/**
 * Handles the click event for the update button of an extension.
 * This function makes a POST request to '/update_extension' with the extension's name.
 * If the extension is already up to date, it displays a success message.
 * If the extension is not up to date, it updates the extension and displays a success message with the new commit hash.
 */
async function onUpdateClick() {
    const extensionName = $(this).data('name');
    await updateExtension(extensionName, false);
}

/**
 * Updates a third-party extension via the API.
 * @param {string} extensionName Extension folder name
 * @param {boolean} quiet If true, don't show a success message
 */
async function updateExtension(extensionName, quiet) {
    try {
        const response = await fetch('/api/extensions/update', {
            method: 'POST',
            headers: getRequestHeaders(),
            body: JSON.stringify({ extensionName })
        });

        const data = await response.json();
        if (data.isUpToDate) {
            if (!quiet) {
                toastr.success('Extension is already up to date');
            }
        } else {
            toastr.success(`Extension ${extensionName} updated to ${data.shortCommitHash}`);
        }

        if (!quiet) {
            showExtensionsDetails();
        }
    } catch (error) {
        console.error('Error:', error);
    }
}

/**
 * Handles the click event for the delete button of an extension.
 * This function makes a POST request to '/api/extensions/delete' with the extension's name.
 * If the extension is deleted, it displays a success message.
 * Creates a popup for the user to confirm before delete.
 */
async function onDeleteClick() {
    const extensionName = $(this).data('name');
    // use callPopup to create a popup for the user to confirm before delete
    const confirmation = await callPopup(`Are you sure you want to delete ${extensionName}?`, 'delete_extension');
    if (confirmation) {
        await deleteExtension(extensionName);
    }
};

export async function deleteExtension(extensionName) {
    try {
        const response = await fetch('/api/extensions/delete', {
            method: 'POST',
            headers: getRequestHeaders(),
            body: JSON.stringify({ extensionName })
        });
    } catch (error) {
        console.error('Error:', error);
    }

    toastr.success(`Extension ${extensionName} deleted`);
    showExtensionsDetails();
    // reload the page to remove the extension from the list
    location.reload();
}

/**
 * Fetches the version details of a specific extension.
 *
 * @param {string} extensionName - The name of the extension.
 * @return {Promise<object>} - An object containing the extension's version details.
 * This object includes the currentBranchName, currentCommitHash, isUpToDate, and remoteUrl.
 * @throws {error} - If there is an error during the fetch operation, it logs the error to the console.
 */
async function getExtensionVersion(extensionName) {
    try {
        const response = await fetch('/api/extensions/version', {
            method: 'POST',
            headers: getRequestHeaders(),
            body: JSON.stringify({ extensionName })
        });

        const data = await response.json();
        return data;
    } catch (error) {
        console.error('Error:', error);
    }
}

/**
 * Installs a third-party extension via the API.
 * @param {string} url Extension repository URL
 * @returns {Promise<void>}
 */
export async function installExtension(url) {
    console.debug('Extension import started', url);

    const request = await fetch('/api/extensions/install', {
        method: 'POST',
        headers: getRequestHeaders(),
        body: JSON.stringify({ url }),
    });

    if (!request.ok) {
        toastr.info(request.statusText, 'Extension import failed');
        console.error('Extension import failed', request.status, request.statusText);
        return;
    }

    const response = await request.json();
    toastr.success(`Extension "${response.display_name}" by ${response.author} (version ${response.version}) has been imported successfully!`, 'Extension import successful');
    console.debug(`Extension "${response.display_name}" has been imported successfully at ${response.extensionPath}`);
    await loadExtensionSettings({}, false);
    eventSource.emit(event_types.EXTENSION_SETTINGS_LOADED);
}

/**
 * Loads extension settings from the app settings.
 * @param {object} settings App Settings
 * @param {boolean} versionChanged Is this a version change?
 */
async function loadExtensionSettings(settings, versionChanged) {
    if (settings.extension_settings) {
        Object.assign(extension_settings, settings.extension_settings);
    }

    $("#extensions_url").val(extension_settings.apiUrl);
    $("#extensions_api_key").val(extension_settings.apiKey);
    $("#extensions_autoconnect").prop('checked', extension_settings.autoConnect);

    // Activate offline extensions
    eventSource.emit(event_types.EXTENSIONS_FIRST_LOAD);
    extensionNames = await discoverExtensions();
    manifests = await getManifests(extensionNames)

    if (versionChanged) {
        await autoUpdateExtensions();
    }

    await activateExtensions();
    if (extension_settings.autoConnect && extension_settings.apiUrl) {
        connectToApi(extension_settings.apiUrl);
    }

}

async function autoUpdateExtensions() {
    for (const [id, manifest] of Object.entries(manifests)) {
        if (manifest.auto_update && id.startsWith('third-party')) {
            console.debug(`Auto-updating 3rd-party extension: ${manifest.display_name} (${id})`);
            await updateExtension(id.replace('third-party', ''), true);
        }
    }
}

async function runGenerationInterceptors(chat, contextSize) {
    for (const manifest of Object.values(manifests)) {
        const interceptorKey = manifest.generate_interceptor;
        if (typeof window[interceptorKey] === 'function') {
            try {
                await window[interceptorKey](chat, contextSize);
            } catch (e) {
                console.error(`Failed running interceptor for ${manifest.display_name}`, e);
            }
        }
    }
}

jQuery(function () {
    addExtensionsButtonAndMenu();
    $("#extensionsMenuButton").css("display", "flex");

    $("#extensions_connect").on('click', connectClickHandler);
    $("#extensions_autoconnect").on('input', autoConnectInputHandler);
    $("#extensions_details").on('click', showExtensionsDetails);
    $(document).on('click', '.toggle_disable', onDisableExtensionClick);
    $(document).on('click', '.toggle_enable', onEnableExtensionClick);
    $(document).on('click', '.btn_update', onUpdateClick);
    $(document).on('click', '.btn_delete', onDeleteClick);
});