import { callPopup, chat_metadata, eventSource, event_types, generateQuietPrompt, getCurrentChatId, getRequestHeaders, getThumbnailUrl, saveSettingsDebounced } from '../script.js';
import { saveMetadataDebounced } from './extensions.js';
import { registerSlashCommand } from './slash-commands.js';
import { flashHighlight, stringFormat } from './utils.js';

const BG_METADATA_KEY = 'custom_background';
const LIST_METADATA_KEY = 'chat_backgrounds';

export let background_settings = {
    name: '__transparent.png',
    url: generateUrlParameter('__transparent.png', false),
};

export function loadBackgroundSettings(settings) {
    let backgroundSettings = settings.background;
    if (!backgroundSettings || !backgroundSettings.name || !backgroundSettings.url) {
        backgroundSettings = background_settings;
    }
    setBackground(backgroundSettings.name, backgroundSettings.url);
}

/**
 * Sets the background for the current chat and adds it to the list of custom backgrounds.
 * @param {{url: string, path:string}} backgroundInfo
 */
function forceSetBackground(backgroundInfo) {
    saveBackgroundMetadata(backgroundInfo.url);
    setCustomBackground();

    const list = chat_metadata[LIST_METADATA_KEY] || [];
    const bg = backgroundInfo.path;
    list.push(bg);
    chat_metadata[LIST_METADATA_KEY] = list;
    saveMetadataDebounced();
    getChatBackgroundsList();
    highlightNewBackground(bg);
    highlightLockedBackground();
}

async function onChatChanged() {
    if (hasCustomBackground()) {
        setCustomBackground();
    }
    else {
        unsetCustomBackground();
    }

    getChatBackgroundsList();
    highlightLockedBackground();
}

function getChatBackgroundsList() {
    const list = chat_metadata[LIST_METADATA_KEY];
    const listEmpty = !Array.isArray(list) || list.length === 0;

    $('#bg_custom_content').empty();
    $('#bg_chat_hint').toggle(listEmpty);

    if (listEmpty) {
        return;
    }

    for (const bg of list) {
        const template = getBackgroundFromTemplate(bg, true);
        $('#bg_custom_content').append(template);
    }
}

function getBackgroundPath(fileUrl) {
    return `backgrounds/${fileUrl}`;
}

function highlightLockedBackground() {
    $('.bg_example').removeClass('locked');

    const lockedBackground = chat_metadata[BG_METADATA_KEY];

    if (!lockedBackground) {
        return;
    }

    $('.bg_example').each(function () {
        const url = $(this).data('url');
        if (url === lockedBackground) {
            $(this).addClass('locked');
        }
    });
}

function onLockBackgroundClick(e) {
    e.stopPropagation();

    const chatName = getCurrentChatId();

    if (!chatName) {
        toastr.warning('Select a chat to lock the background for it');
        return;
    }

    const relativeBgImage = getUrlParameter(this);

    saveBackgroundMetadata(relativeBgImage);
    setCustomBackground();
    highlightLockedBackground();
}

function onUnlockBackgroundClick(e) {
    e.stopPropagation();
    removeBackgroundMetadata();
    unsetCustomBackground();
    highlightLockedBackground();
}

function hasCustomBackground() {
    return chat_metadata[BG_METADATA_KEY];
}

function saveBackgroundMetadata(file) {
    chat_metadata[BG_METADATA_KEY] = file;
    saveMetadataDebounced();
}

function removeBackgroundMetadata() {
    delete chat_metadata[BG_METADATA_KEY];
    saveMetadataDebounced();
}

function setCustomBackground() {
    const file = chat_metadata[BG_METADATA_KEY];

    // bg already set
    if (document.getElementById('bg_custom').style.backgroundImage == file) {
        return;
    }

    $('#bg_custom').css('background-image', file);
}

function unsetCustomBackground() {
    $('#bg_custom').css('background-image', 'none');
}

function onSelectBackgroundClick() {
    const isCustom = $(this).attr('custom') === 'true';
    const relativeBgImage = getUrlParameter(this);

    // if clicked on upload button
    if (!relativeBgImage) {
        return;
    }

    // Automatically lock the background if it's custom or other background is locked
    if (hasCustomBackground() || isCustom) {
        saveBackgroundMetadata(relativeBgImage);
        setCustomBackground();
        highlightLockedBackground();
    }
    highlightLockedBackground();

    const customBg = window.getComputedStyle(document.getElementById('bg_custom')).backgroundImage;

    // Custom background is set. Do not override the layer below
    if (customBg !== 'none') {
        return;
    }

    const bgFile = $(this).attr('bgfile');
    const backgroundUrl = getBackgroundPath(bgFile);

    // Fetching to browser memory to reduce flicker
    fetch(backgroundUrl).then(() => {
        setBackground(bgFile, relativeBgImage);
    }).catch(() => {
        console.log('Background could not be set: ' + backgroundUrl);
    });
}

async function onCopyToSystemBackgroundClick(e) {
    e.stopPropagation();
    const bgNames = await getNewBackgroundName(this);

    if (!bgNames) {
        return;
    }

    const bgFile = await fetch(bgNames.oldBg);

    if (!bgFile.ok) {
        toastr.warning('Failed to copy background');
        return;
    }

    const blob = await bgFile.blob();
    const file = new File([blob], bgNames.newBg);
    const formData = new FormData();
    formData.set('avatar', file);

    uploadBackground(formData);

    const list = chat_metadata[LIST_METADATA_KEY] || [];
    const index = list.indexOf(bgNames.oldBg);
    list.splice(index, 1);
    saveMetadataDebounced();
    getChatBackgroundsList();
}

/**
 * Gets the new background name from the user.
 * @param {Element} referenceElement
 * @returns {Promise<{oldBg: string, newBg: string}>}
 * */
async function getNewBackgroundName(referenceElement) {
    const exampleBlock = $(referenceElement).closest('.bg_example');
    const isCustom = exampleBlock.attr('custom') === 'true';
    const oldBg = exampleBlock.attr('bgfile');

    if (!oldBg) {
        console.debug('no bgfile');
        return;
    }

    const fileExtension = oldBg.split('.').pop();
    const fileNameBase = isCustom ? oldBg.split('/').pop() : oldBg;
    const oldBgExtensionless = fileNameBase.replace(`.${fileExtension}`, '');
    const newBgExtensionless = await callPopup('<h3>Enter new background name:</h3>', 'input', oldBgExtensionless);

    if (!newBgExtensionless) {
        console.debug('no new_bg_extensionless');
        return;
    }

    const newBg = `${newBgExtensionless}.${fileExtension}`;

    if (oldBgExtensionless === newBgExtensionless) {
        console.debug('new_bg === old_bg');
        return;
    }

    return { oldBg, newBg };
}

async function onRenameBackgroundClick(e) {
    e.stopPropagation();

    const bgNames = await getNewBackgroundName(this);

    if (!bgNames) {
        return;
    }

    const data = { old_bg: bgNames.oldBg, new_bg: bgNames.newBg };
    const response = await fetch('/api/backgrounds/rename', {
        method: 'POST',
        headers: getRequestHeaders(),
        body: JSON.stringify(data),
        cache: 'no-cache',
    });

    if (response.ok) {
        await getBackgrounds();
        highlightNewBackground(bgNames.newBg);
    } else {
        toastr.warning('Failed to rename background');
    }
}

async function onDeleteBackgroundClick(e) {
    e.stopPropagation();
    const bgToDelete = $(this).closest('.bg_example');
    const url = bgToDelete.data('url');
    const isCustom = bgToDelete.attr('custom') === 'true';
    const confirm = await callPopup('<h3>Delete the background?</h3>', 'confirm');
    const bg = bgToDelete.attr('bgfile');

    if (confirm) {
        // If it's not custom, it's a built-in background. Delete it from the server
        if (!isCustom) {
            delBackground(bg);
        } else {
            const list = chat_metadata[LIST_METADATA_KEY] || [];
            const index = list.indexOf(bg);
            list.splice(index, 1);
        }

        const siblingSelector = '.bg_example:not(#form_bg_download)';
        const nextBg = bgToDelete.next(siblingSelector);
        const prevBg = bgToDelete.prev(siblingSelector);
        const anyBg = $(siblingSelector);

        if (nextBg.length > 0) {
            nextBg.trigger('click');
        } else if (prevBg.length > 0) {
            prevBg.trigger('click');
        } else {
            $(anyBg[Math.floor(Math.random() * anyBg.length)]).trigger('click');
        }

        bgToDelete.remove();

        if (url === chat_metadata[BG_METADATA_KEY]) {
            removeBackgroundMetadata();
            unsetCustomBackground();
            highlightLockedBackground();
        }

        if (isCustom) {
            getChatBackgroundsList();
            saveMetadataDebounced();
        }
    }
}

const autoBgPrompt = 'Pause your roleplay and choose a location ONLY from the provided list that is the most suitable for the current scene. Do not output any other text:\n{0}';

async function autoBackgroundCommand() {
    /** @type {HTMLElement[]} */
    const bgTitles = Array.from(document.querySelectorAll('#bg_menu_content .BGSampleTitle'));
    const options = bgTitles.map(x => ({ element: x, text: x.innerText.trim() })).filter(x => x.text.length > 0);
    if (options.length == 0) {
        toastr.warning('No backgrounds to choose from. Please upload some images to the "backgrounds" folder.');
        return;
    }

    const list = options.map(option => `- ${option.text}`).join('\n');
    const prompt = stringFormat(autoBgPrompt, list);
    const reply = await generateQuietPrompt(prompt, false, false);
    const fuse = new Fuse(options, { keys: ['text'] });
    const bestMatch = fuse.search(reply, { limit: 1 });

    if (bestMatch.length == 0) {
        toastr.warning('No match found. Please try again.');
        return;
    }

    console.debug('Automatically choosing background:', bestMatch);
    bestMatch[0].item.element.click();
}

export async function getBackgrounds() {
    const response = await fetch('/api/backgrounds/all', {
        method: 'POST',
        headers: getRequestHeaders(),
        body: JSON.stringify({
            '': '',
        }),
    });
    if (response.ok) {
        const getData = await response.json();
        //background = getData;
        //console.log(getData.length);
        $('#bg_menu_content').children('div').remove();
        for (const bg of getData) {
            const template = getBackgroundFromTemplate(bg, false);
            $('#bg_menu_content').append(template);
        }
    }
}

/**
 * Gets the CSS URL of the background
 * @param {Element} block
 * @returns {string} URL of the background
 */
function getUrlParameter(block) {
    return $(block).closest('.bg_example').data('url');
}

function generateUrlParameter(bg, isCustom) {
    return isCustom ? `url("${encodeURI(bg)}")` : `url("${getBackgroundPath(bg)}")`;
}

/**
 * Instantiates a background template
 * @param {string} bg Path to background
 * @param {boolean} isCustom Whether the background is custom
 * @returns {JQuery<HTMLElement>} Background template
 */
function getBackgroundFromTemplate(bg, isCustom) {
    const template = $('#background_template .bg_example').clone();
    const thumbPath = isCustom ? bg : getThumbnailUrl('bg', bg);
    const url = generateUrlParameter(bg, isCustom);
    const title = isCustom ? bg.split('/').pop() : bg;
    const friendlyTitle = title.slice(0, title.lastIndexOf('.'));
    template.attr('title', title);
    template.attr('bgfile', bg);
    template.attr('custom', String(isCustom));
    template.data('url', url);
    template.css('background-image', `url('${thumbPath}')`);
    template.find('.BGSampleTitle').text(friendlyTitle);
    return template;
}

async function setBackground(bg, url) {
    $('#bg1').css('background-image', url);
    background_settings.name = bg;
    background_settings.url = url;
    saveSettingsDebounced();
}

async function delBackground(bg) {
    await fetch('/api/backgrounds/delete', {
        method: 'POST',
        headers: getRequestHeaders(),
        body: JSON.stringify({
            bg: bg,
        }),
    });
}

function onBackgroundUploadSelected() {
    const form = $('#form_bg_download').get(0);

    if (!(form instanceof HTMLFormElement)) {
        console.error('form_bg_download is not a form');
        return;
    }

    const formData = new FormData(form);
    uploadBackground(formData);
    form.reset();
}

/**
 * Uploads a background to the server
 * @param {FormData} formData
 */
function uploadBackground(formData) {
    jQuery.ajax({
        type: 'POST',
        url: '/api/backgrounds/upload',
        data: formData,
        beforeSend: function () {
        },
        cache: false,
        contentType: false,
        processData: false,
        success: async function (bg) {
            setBackground(bg, generateUrlParameter(bg, false));
            await getBackgrounds();
            highlightNewBackground(bg);
        },
        error: function (jqXHR, exception) {
            console.log(exception);
            console.log(jqXHR);
        },
    });
}

/**
 * @param {string} bg
 */
function highlightNewBackground(bg) {
    const newBg = $(`.bg_example[bgfile="${bg}"]`);
    const scrollOffset = newBg.offset().top - newBg.parent().offset().top;
    $('#Backgrounds').scrollTop(scrollOffset);
    flashHighlight(newBg);
}

function onBackgroundFilterInput() {
    const filterValue = String($(this).val()).toLowerCase();
    $('#bg_menu_content > div').each(function () {
        const $bgContent = $(this);
        if ($bgContent.attr('title').toLowerCase().includes(filterValue)) {
            $bgContent.show();
        } else {
            $bgContent.hide();
        }
    });
}

export function initBackgrounds() {
    eventSource.on(event_types.CHAT_CHANGED, onChatChanged);
    eventSource.on(event_types.FORCE_SET_BACKGROUND, forceSetBackground);
    $(document).on('click', '.bg_example', onSelectBackgroundClick);
    $(document).on('click', '.bg_example_lock', onLockBackgroundClick);
    $(document).on('click', '.bg_example_unlock', onUnlockBackgroundClick);
    $(document).on('click', '.bg_example_edit', onRenameBackgroundClick);
    $(document).on('click', '.bg_example_cross', onDeleteBackgroundClick);
    $(document).on('click', '.bg_example_copy', onCopyToSystemBackgroundClick);
    $('#auto_background').on('click', autoBackgroundCommand);
    $('#add_bg_button').on('change', onBackgroundUploadSelected);
    $('#bg-filter').on('input', onBackgroundFilterInput);
    registerSlashCommand('lockbg', onLockBackgroundClick, ['bglock'], '– locks a background for the currently selected chat', true, true);
    registerSlashCommand('unlockbg', onUnlockBackgroundClick, ['bgunlock'], '– unlocks a background for the currently selected chat', true, true);
    registerSlashCommand('autobg', autoBackgroundCommand, ['bgauto'], '– automatically changes the background based on the chat context using the AI request prompt', true, true);
}