import { Marked, type MarkedExtension, type Tokens } from 'marked';
import {createDirectives, presetDirectiveConfigs} from 'marked-directive';
import yaml from 'js-yaml';
import markedAlert from "marked-alert";
import markedMermaid from "./mermaid";
import {gfmHeadingId} from "marked-gfm-heading-id";

let globalIconPrefix: string | undefined = undefined;
function overrideIconPrefix(path?: string){
    globalIconPrefix = path;
    return {
        [Symbol.dispose](){
            globalIconPrefix = undefined;
        }
    }
}

/**
 * 将表格数据转换为 CSV 格式字符串
 * @param headers 表头数组
 * @param rows 表格数据行
 * @returns CSV 格式字符串
 */
function tableToCSV(headers: string[], rows: string[][]): string {
    const escapeCell = (cell: string) => {
        // 如果单元格包含逗号、换行或引号，需要转义
        if (cell.includes(',') || cell.includes('\n') || cell.includes('"')) {
            return `"${cell.replace(/"/g, '""')}"`;
        }
        return cell;
    };
    
    const headerLine = headers.map(escapeCell).join(',');
    const dataLines = rows.map(row => row.map(escapeCell).join(','));
    
    return [headerLine, ...dataLines].join('\n');
}

// 使用 marked-directive 来支持指令语法
const marked = new Marked()
    .use(gfmHeadingId())
    .use(markedAlert())
    .use(markedMermaid())
    .use(createDirectives([
    ...presetDirectiveConfigs,
    {
        marker: '::::',
        level: 'container'
    },
    {
        marker: ':::::',
        level: 'container'
    },
    {
        level: 'inline',
        marker: ':',
        // :[blah] becomes <i class="icon icon-blah"></i>
        renderer(token) {
            if (!token.meta.name) {
                const style = globalIconPrefix ? `style="--icon-src: url('${globalIconPrefix}/${token.text}.png')"` : '';
                return `<icon ${style} class="icon-${token.text}"></icon>`;
            }
            return false;
        }
    },
]), {
    // 自定义代码块渲染器，支持 yaml/tag 格式
    extensions: [{
        name: 'code-block-yaml-tag',
        level: 'block',
        start(src: string) {
            // 检测 ```yaml/tag 开头的代码块
            return src.match(/^```yaml\/tag\s*\n/m)?.index;
        },
        tokenizer(src: string) {
            const rule = /^```yaml\/tag\s*\n([\s\S]*?)\n```/;
            const match = rule.exec(src);
            if (match) {
                const yamlContent = match[1]?.trim() || '';
                const props = yaml.load(yamlContent) as Record<string, unknown> || {};

                // 提取 tag 名称，默认为 tag-unknown
                const tagName = (props.tag as string) || 'tag-unknown';

                // 移除 tag 属性，剩下的作为 HTML 属性
                const { tag, ...rest } = props;

                // 提取 innerText 内容（如果有 body 字段）
                let content = '';
                if ('body' in rest) {
                    content = String(rest.body || '');
                    delete (rest as Record<string, unknown>).body;
                }

                // 构建属性字符串
                const propsStr = Object.entries(rest)
                    .map(([key, value]) => {
                        const strValue = String(value);
                        // 如果值包含空格或特殊字符，添加引号
                        if (strValue.includes(' ') || strValue.includes('"')) {
                            return `${key}="${strValue.replace(/"/g, '&quot;')}"`;
                        }
                        return `${key}="${strValue}"`;
                    })
                    .join(' ');

                return {
                    type: 'code-block-yaml-tag',
                    raw: match[0],
                    tagName,
                    props: propsStr,
                    content
                };
            }
        },
        renderer(token: any) {
            // 渲染为自定义 HTML 标签
            const propsAttr = token.props ? ` ${token.props}` : '';
            return `<${token.tagName}${propsAttr}>${token.content || ''}</${token.tagName}>\n`;
        }
    }]
});

// 覆盖默认的 table renderer 以支持自动转换
marked.use({
    renderer: {
        table(token: Tokens.Table) {
            // 检查表头是否包含 md-table-label
            const header = token.header;
            const labelIndex = header.findIndex(cell => cell.text === 'md-table-label');
            
            if (labelIndex !== -1) {
                // 将 md-table-label 列转换为 label
                const headers = header.map(cell => cell.text === 'md-table-label' ? 'label' : cell.text);
                
                // 转换所有行
                const rows = token.rows.map(row => 
                    row.map(cell => cell.text)
                );
                
                // 生成 CSV 数据
                const csvData = tableToCSV(headers, rows);
                
                // 渲染为 md-table 组件，内联 CSV 数据
                return `<md-table>${csvData}</md-table>\n`;
            }
            
            // 默认表格渲染 - 使用 marked 默认行为
            return false;
        }
    }
} as MarkedExtension);

export function parseMarkdown(content: string, iconPrefix?: string): string {
    using prefix = overrideIconPrefix(iconPrefix);
    return marked.parse(content.trimStart()) as string;
}

export { marked };