/**
 * 文件：wechat/wechat-preview.ts
 * 作用：微信公众号预览视图组件，专门处理微信公众号平台的预览和发布功能
 * 
 * 功能：
 * 1. 渲染微信公众号专属的工具栏和预览界面
 * 2. 处理文章的复制、上传图片、发布草稿等操作
 * 3. 管理微信公众号相关的设置（公众号选择、封面、样式等）
 * 4. 提供文章导出HTML功能
 */

import { Notice, Platform, TFile } from 'obsidian';
import { NMPSettings } from '../settings';
import AssetsManager from '../assets';
import { ArticleRender } from '../article-render';
import { uevent } from '../utils';

/**
 * 微信公众号预览视图类
 */
export class WechatPreview {
    container: HTMLElement;
    settings: NMPSettings;
    assetsManager: AssetsManager;
    render: ArticleRender;
    app: any;
    
    // 当前状态
    currentFile: TFile | null = null;
    currentAppId: string = '';
    currentTheme: string;
    currentHighlight: string;
    
    // UI 元素
    board: HTMLDivElement | null = null;
    contentCell: HTMLElement | null = null;
    contentEl: HTMLElement | null = null;
    wechatSelect: HTMLSelectElement | null = null;
    themeSelect: HTMLSelectElement | null = null;
    highlightSelect: HTMLSelectElement | null = null;
    coverEl: HTMLInputElement | null = null;
    useDefaultCover: HTMLInputElement | null = null;
    useLocalCover: HTMLInputElement | null = null;
    
    // 回调函数
    onRefreshCallback?: () => Promise<void>;
    onAppIdChangeCallback?: (appId: string) => void;

    constructor(container: HTMLElement, app: any, render: ArticleRender) {
        this.container = container;
        this.app = app;
        this.render = render;
        this.settings = NMPSettings.getInstance();
        this.assetsManager = AssetsManager.getInstance();
        this.currentTheme = this.settings.defaultStyle;
        this.currentHighlight = this.settings.defaultHighlight;
        
        // 初始化默认公众号
        if (this.settings.wxInfo.length > 0) {
            this.currentAppId = this.settings.wxInfo[0].appid;
        }
    }

    /**
     * 构建微信公众号预览界面
     */
    build(): void {
        this.container.empty();
        this.container.addClass('wechat-preview-container');

        this.board = this.container.createDiv({ cls: 'wechat-board' });

        this.buildAccountRow();

        //this.buildCoverRow();
        //this.buildStyleRow();

        this.contentCell = this.createCell('content');
        this.contentCell.addClass('wechat-cell-content');

        this.mountArticle(this.board);
    }

    private createCell(area: string, tag: keyof HTMLElementTagNameMap = 'div', extraClasses: string[] = []): HTMLElement {
        if (!this.board) {
            throw new Error('Wechat board not initialized');
        }
        const cell = this.board.createEl(tag, { attr: { 'data-area': area } });
        cell.addClass('wechat-cell');
        for (const cls of extraClasses) {
            cell.addClass(cls);
        }
        return cell;
    }

    private buildAccountRow(): void {
        const selectCell = this.createCell('account-select');
        const selectLabel = selectCell.createEl('label', {
            cls: 'style-label',
            attr: { for: 'wechat-account-select' },
            text: '公众号'
        });
        selectLabel.addClass('wechat-account-label');

        const wxSelect = selectCell.createEl('select', {
            cls: 'wechat-select',
            attr: { id: 'wechat-account-select' }
        }) as HTMLSelectElement;
        wxSelect.onchange = async () => {
            this.currentAppId = wxSelect.value;
            this.onAppIdChanged();
        };

        const defaultOp = wxSelect.createEl('option');
        defaultOp.value = '';
        defaultOp.text = '请在设置里配置公众号';

        for (let i = 0; i < this.settings.wxInfo.length; i++) {
            const op = wxSelect.createEl('option');
            const wx = this.settings.wxInfo[i];
            op.value = wx.appid;
            op.text = wx.name;
            if (i === 0) {
                op.selected = true;
                this.currentAppId = wx.appid;
            }
        }
        this.wechatSelect = wxSelect;

        const actionsCell = this.createCell('account-back-export');
        if (Platform.isDesktop) {
            const openBtn = actionsCell.createEl('button', {
                text: '访问后台',
                cls: 'toolbar-button purple-gradient wechat-action-button'
            });
            openBtn.onclick = async () => {
                const { shell } = require('electron');
                shell.openExternal('https://mp.weixin.qq.com');
                uevent('open-mp');
            };
        }

        if (Platform.isDesktop && this.settings.isAuthKeyVaild()) {
            const exportBtn = actionsCell.createEl('button', { text: '导出页面', cls: 'toolbar-button wechat-action-button' });
            exportBtn.onclick = async () => await this.exportHTML();
        }

        if (actionsCell.childElementCount === 0) {
            actionsCell.addClass('wechat-cell-placeholder');
        }
    }

    private buildCoverRow(): void {
        const selectCell = this.createCell('cover-select');
        selectCell.createDiv({ cls: 'style-label', text: '封面' });

        this.useDefaultCover = selectCell.createEl('input', { cls: 'input-style' }) as HTMLInputElement;
        this.useDefaultCover.setAttr('type', 'radio');
        this.useDefaultCover.setAttr('name', 'cover');
        this.useDefaultCover.setAttr('value', 'default');
        this.useDefaultCover.setAttr('checked', true);
        this.useDefaultCover.id = 'default-cover';
        this.useDefaultCover.onchange = async () => {
            if (this.useDefaultCover?.checked && this.coverEl) {
                this.coverEl.setAttr('style', 'visibility:hidden;width:0px;');
            }
        };
        selectCell.createEl('label', { text: '默认', attr: { for: 'default-cover' } });

        this.useLocalCover = selectCell.createEl('input', { cls: 'input-style' }) as HTMLInputElement;
        this.useLocalCover.setAttr('type', 'radio');
        this.useLocalCover.setAttr('name', 'cover');
        this.useLocalCover.setAttr('value', 'local');
        this.useLocalCover.id = 'local-cover';
        this.useLocalCover.onchange = async () => {
            if (this.useLocalCover?.checked && this.coverEl) {
                this.coverEl.setAttr('style', 'visibility:visible;width:180px;');
            }
        };
        selectCell.createEl('label', { text: '上传', attr: { for: 'local-cover' } });

        const inputCell = this.createCell('cover-input');
        this.coverEl = inputCell.createEl('input', {
            cls: 'upload-input',
            attr: {
                type: 'file',
                placeholder: '封面图片',
                accept: '.png, .jpg, .jpeg',
                name: 'cover',
                id: 'cover-input'
            }
        }) as HTMLInputElement;
        if (this.useDefaultCover?.checked) {
            this.coverEl.setAttr('style', 'visibility:hidden;width:0px;');
        }
    }

    private buildStyleRow(): void {
        const styleLabelCell = this.createCell('style-label', 'div', ['style-label']);
        styleLabelCell.setText('样式');

        const styleSelectCell = this.createCell('style-select');
        const selectBtn = styleSelectCell.createEl('select', { cls: 'style-select wechat-style-select' }) as HTMLSelectElement;
        selectBtn.onchange = async () => {
            this.currentTheme = selectBtn.value;
            this.render.updateStyle(selectBtn.value);
        };

        for (let s of this.assetsManager.themes) {
            const op = selectBtn.createEl('option');
            op.value = s.className;
            op.text = s.name;
            op.selected = s.className === this.settings.defaultStyle;
        }
        this.themeSelect = selectBtn;

        const highlightLabelCell = this.createCell('highlight-label', 'div', ['style-label']);
        highlightLabelCell.setText('代码高亮');

        const highlightSelectCell = this.createCell('highlight-select');
        const highlightStyleBtn = highlightSelectCell.createEl('select', { cls: 'style-select wechat-style-select' }) as HTMLSelectElement;
        highlightStyleBtn.onchange = async () => {
            this.currentHighlight = highlightStyleBtn.value;
            this.render.updateHighLight(highlightStyleBtn.value);
        };

        const highlights = this.assetsManager.highlights;
        for (let h of highlights) {
            const op = highlightStyleBtn.createEl('option');
            op.value = h.url;
            op.text = h.name;
            op.selected = h.url === this.currentHighlight;
        }
        this.highlightSelect = highlightStyleBtn;
    }

    private mountArticle(_parent: HTMLElement): void {
        if (!this.contentCell) {
            return;
        }
        try {
            if (this.render?.styleEl && !this.contentCell.contains(this.render.styleEl)) {
                this.contentCell.appendChild(this.render.styleEl);
            }
            if (this.render?.articleDiv) {
                this.render.articleDiv.addClass('wechat-article-wrapper');
                if (this.render.articleDiv.parentElement !== this.contentCell) {
                    this.contentCell.appendChild(this.render.articleDiv);
                }
                this.contentEl = this.render.articleDiv;
            }
        } catch (error) {
            console.warn('[WechatPreview] 挂载文章容器失败', error);
        }
    }

    /**
     * 构建封面选择器
     */
    /**
     * 显示微信预览视图
     */
    show(): void {
        if (this.container) {
            this.container.style.display = 'flex';
        }
    }

    /**
     * 隐藏微信预览视图
     */
    hide(): void {
        if (this.container) {
            this.container.style.display = 'none';
        }
    }

    /**
     * 公众号切换处理
     */
    private onAppIdChanged(): void {
        if (this.onAppIdChangeCallback) {
            this.onAppIdChangeCallback(this.currentAppId);
        }
    }

    /**
     * 上传图片
     */
    private async uploadImages(): Promise<void> {
        // 待实现 - 从原来的 note-preview.ts 迁移
        new Notice('上传图片功能');
        uevent('upload');
    }

    /**
     * 发布草稿
     */
    private async postArticle(): Promise<void> {
        try {
            if (!this.currentFile) {
                new Notice('请先打开一个 Markdown 文件');
                return;
            }
            if (!this.currentAppId) {
                new Notice('请先在设置中配置公众号信息');
                return;
            }
            new Notice('正在创建公众号草稿...');
            const mediaId = await this.render.postArticle(this.currentAppId, this.getLocalCoverFile());
            if (mediaId) {
                new Notice('草稿创建成功');
            }
            uevent('pub');
        } catch (e) {
            console.error(e);
            new Notice('发布失败: ' + (e instanceof Error ? e.message : e));
        }
    }

    /**
     * 发布图片/文字
     */
    private async postImages(): Promise<void> {
        try {
            if (!this.currentFile) {
                new Notice('请先打开一个 Markdown 文件');
                return;
            }
            if (!this.currentAppId) {
                new Notice('请先在设置中配置公众号信息');
                return;
            }
            new Notice('正在创建图片/文字消息草稿...');
            const mediaId = await this.render.postImages(this.currentAppId);
            if (mediaId) {
                new Notice('图片/文字草稿创建成功');
            }
            uevent('pub-images');
        } catch (e) {
            console.error(e);
            new Notice('发布失败: ' + (e instanceof Error ? e.message : e));
        }
    }

    /**
     * 导出HTML
     */
    private async exportHTML(): Promise<void> {
        try {
            if (!this.currentFile) {
                new Notice('请先打开一个 Markdown 文件');
                return;
            }
            await this.render.exportHTML();
            new Notice('HTML 导出完成');
            uevent('export-html');
        } catch (e) {
            console.error(e);
            new Notice('导出失败: ' + (e instanceof Error ? e.message : e));
        }
    }

    /**
     * 更新样式和高亮显示
     */
    updateStyleAndHighlight(theme: string, highlight: string): void {
        this.currentTheme = theme;
        this.currentHighlight = highlight;
        
        if (this.themeSelect) {
            this.themeSelect.value = theme;
        }
        if (this.highlightSelect) {
            this.highlightSelect.value = highlight;
        }
    }

    /**
     * 清理资源
     */
    destroy(): void {
        this.board = null;
        this.contentCell = null;
        this.contentEl = null;
        this.wechatSelect = null;
        this.themeSelect = null;
        this.highlightSelect = null;
        this.coverEl = null;
        this.useDefaultCover = null;
        this.useLocalCover = null;
    }

    /** 获取本地上传封面（如果选择了“上传”单选并选了文件） */
    private getLocalCoverFile(): File | null {
        if (this.useLocalCover?.checked && this.coverEl?.files && this.coverEl.files.length > 0) {
            return this.coverEl.files[0];
        }
        return null;
    }

    /** 对外：发布草稿（供外层菜单调用） */
    async postDraft() { await this.postArticle(); }

    async publish(): Promise<void> {
        await this.postDraft();
    }

    async refresh(): Promise<void> {
        if (this.onRefreshCallback) {
            await this.onRefreshCallback();
        }
    }

    /** 由上层在切换/渲染时注入当前文件 */
    setFile(file: TFile | null) { this.currentFile = file; }
}