/**
 * Code Execution 工具服务
 * 混合架构：Pyodide (浏览器端 Python) + Piston API (服务端多语言)
 *
 * - Python + 图形绘制 → Pyodide (支持 matplotlib 渲染)
 * - 其他语言/普通代码 → Piston API
 *
 * Piston API 文档: https://github.com/engineer-man/piston
 * Pyodide 文档: https://pyodide.org/
 */

import {
  shouldUsePyodide,
  executePythonInPyodide,
  type LoadingCallback,
  type PyodideExecutionResult,
} from './pyodideRunner';

export interface CodeExecutionInput {
  code: string;
  language: string;
  stdin?: string;
  /** Pyodide 加载进度回调（可选） */
  onProgress?: LoadingCallback;
}

export interface CodeExecutionResponse {
  success: boolean;
  output?: string;
  error?: string;
  language?: string;
  version?: string;
  /** Base64 编码的图片数组（matplotlib 输出） */
  images?: string[];
  /** 执行引擎: 'pyodide' | 'piston' */
  engine?: 'pyodide' | 'piston';
  /** 执行时间 (ms) */
  executionTime?: number;
}

// Piston API 支持的语言映射
const LANGUAGE_MAP: Record<string, { language: string; version: string }> = {
  python: { language: 'python', version: '3.10.0' },
  python3: { language: 'python', version: '3.10.0' },
  javascript: { language: 'javascript', version: '18.15.0' },
  js: { language: 'javascript', version: '18.15.0' },
  typescript: { language: 'typescript', version: '5.0.3' },
  ts: { language: 'typescript', version: '5.0.3' },
  java: { language: 'java', version: '15.0.2' },
  c: { language: 'c', version: '10.2.0' },
  cpp: { language: 'c++', version: '10.2.0' },
  'c++': { language: 'c++', version: '10.2.0' },
  go: { language: 'go', version: '1.16.2' },
  rust: { language: 'rust', version: '1.68.2' },
  ruby: { language: 'ruby', version: '3.0.1' },
  php: { language: 'php', version: '8.2.3' },
  swift: { language: 'swift', version: '5.3.3' },
  kotlin: { language: 'kotlin', version: '1.8.20' },
  scala: { language: 'scala', version: '3.2.2' },
  r: { language: 'r', version: '4.1.1' },
  bash: { language: 'bash', version: '5.2.0' },
  shell: { language: 'bash', version: '5.2.0' },
  sql: { language: 'sqlite3', version: '3.36.0' },
  lua: { language: 'lua', version: '5.4.4' },
  perl: { language: 'perl', version: '5.36.0' },
  haskell: { language: 'haskell', version: '9.0.1' },
  elixir: { language: 'elixir', version: '1.14.3' },
  clojure: { language: 'clojure', version: '1.10.3' },
};

// Piston API 端点
const PISTON_API_URL = 'https://emkc.org/api/v2/piston/execute';

/**
 * 执行代码
 * 智能选择执行引擎：
 * - Python + 图形代码 → Pyodide (浏览器端)
 * - 其他情况 → Piston API (服务端)
 */
export async function executeCode(input: CodeExecutionInput): Promise<CodeExecutionResponse> {
  const { code, language, stdin, onProgress } = input;
  const startTime = Date.now();

  // 检查是否应该使用 Pyodide（Python + 图形）
  if (shouldUsePyodide(code, language)) {
    return executePythonWithPyodide(code, onProgress, startTime);
  }

  // 使用 Piston API 执行
  return executePythonWithPiston(code, language, stdin, startTime);
}

/**
 * 使用 Pyodide 执行 Python 代码（支持 matplotlib 图形）
 */
async function executePythonWithPyodide(
  code: string,
  onProgress?: LoadingCallback,
  startTime?: number
): Promise<CodeExecutionResponse> {
  const start = startTime || Date.now();

  try {
    const result: PyodideExecutionResult = await executePythonInPyodide(code, onProgress);

    return {
      success: result.success,
      output: result.output,
      error: result.error,
      language: 'python',
      version: 'Pyodide (WebAssembly)',
      images: result.images,
      engine: 'pyodide',
      executionTime: Date.now() - start,
    };
  } catch (error) {
    return {
      success: false,
      error: error instanceof Error ? error.message : '执行错误',
      language: 'python',
      engine: 'pyodide',
      executionTime: Date.now() - start,
    };
  }
}

/**
 * 使用 Piston API 执行代码
 */
async function executePythonWithPiston(
  code: string,
  language: string,
  stdin?: string,
  startTime?: number
): Promise<CodeExecutionResponse> {
  const start = startTime || Date.now();

  // 获取语言映射
  const langConfig = LANGUAGE_MAP[language.toLowerCase()];
  if (!langConfig) {
    return {
      success: false,
      error: `不支持的编程语言: ${language}。支持的语言: ${Object.keys(LANGUAGE_MAP).join(', ')}`,
      engine: 'piston',
      executionTime: Date.now() - start,
    };
  }

  try {
    const response = await fetch(PISTON_API_URL, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({
        language: langConfig.language,
        version: langConfig.version,
        files: [
          {
            name: getFileName(langConfig.language),
            content: code,
          },
        ],
        stdin: stdin || '',
        args: [],
        compile_timeout: 10000,
        run_timeout: 5000,
        compile_memory_limit: -1,
        run_memory_limit: -1,
      }),
    });

    if (!response.ok) {
      const errorText = await response.text();
      console.error('Piston API error:', errorText);
      return {
        success: false,
        error: `代码执行 API 错误: ${response.status}`,
        engine: 'piston',
        executionTime: Date.now() - start,
      };
    }

    const data = await response.json();

    // 检查编译错误
    if (data.compile && data.compile.code !== 0) {
      return {
        success: false,
        error: data.compile.stderr || data.compile.output || '编译错误',
        language: langConfig.language,
        version: langConfig.version,
        engine: 'piston',
        executionTime: Date.now() - start,
      };
    }

    // 检查运行错误
    if (data.run && data.run.code !== 0) {
      return {
        success: true, // 代码执行了，但有运行时错误
        output: data.run.stdout || '',
        error: data.run.stderr || '',
        language: langConfig.language,
        version: langConfig.version,
        engine: 'piston',
        executionTime: Date.now() - start,
      };
    }

    return {
      success: true,
      output: data.run?.stdout || data.run?.output || '',
      error: data.run?.stderr || '',
      language: langConfig.language,
      version: langConfig.version,
      engine: 'piston',
      executionTime: Date.now() - start,
    };
  } catch (error) {
    console.error('Code execution error:', error);
    return {
      success: false,
      error: error instanceof Error ? error.message : '未知错误',
      engine: 'piston',
      executionTime: Date.now() - start,
    };
  }
}

/**
 * 根据语言获取文件名
 */
function getFileName(language: string): string {
  const fileNameMap: Record<string, string> = {
    python: 'main.py',
    javascript: 'main.js',
    typescript: 'main.ts',
    java: 'Main.java',
    c: 'main.c',
    'c++': 'main.cpp',
    go: 'main.go',
    rust: 'main.rs',
    ruby: 'main.rb',
    php: 'main.php',
    swift: 'main.swift',
    kotlin: 'Main.kt',
    scala: 'Main.scala',
    r: 'main.r',
    bash: 'main.sh',
    sqlite3: 'main.sql',
    lua: 'main.lua',
    perl: 'main.pl',
    haskell: 'Main.hs',
    elixir: 'main.exs',
    clojure: 'main.clj',
  };

  return fileNameMap[language] || 'main.txt';
}

/**
 * 格式化代码执行结果为文本（完整版 - 发送给 AI）
 */
export function formatExecutionResult(response: CodeExecutionResponse): string {
  if (!response.success && !response.output && !response.images?.length) {
    return `❌ 执行失败: ${response.error}`;
  }

  let result = '';

  // 执行引擎信息
  if (response.engine) {
    const engineName = response.engine === 'pyodide' ? 'Pyodide (浏览器)' : 'Piston (服务器)';
    result += `**执行引擎**: ${engineName}\n`;
  }

  if (response.language && response.version) {
    result += `**语言**: ${response.language} (${response.version})\n`;
  }

  if (response.executionTime) {
    result += `**执行时间**: ${response.executionTime}ms\n`;
  }

  result += '\n';

  if (response.output) {
    result += `## 输出结果\n\`\`\`\n${response.output}\n\`\`\`\n`;
  }

  // 图片信息（仅标记有图片，实际渲染由前端处理）
  if (response.images && response.images.length > 0) {
    result += `\n## 图形输出\n已生成 ${response.images.length} 张图表\n`;
  }

  if (response.error) {
    result += `\n## 错误信息\n\`\`\`\n${response.error}\n\`\`\`\n`;
  }

  return result || '执行完成，无输出';
}

/**
 * 格式化代码执行结果为简短文本（显示给用户）
 */
export function formatExecutionResultShort(response: CodeExecutionResponse, language: string): string {
  if (!response.success && !response.output && !response.images?.length) {
    return `❌ 代码执行失败: ${response.error}`;
  }

  const langDisplay = response.language || language;
  const engineDisplay = response.engine === 'pyodide' ? ' [Pyodide]' : '';
  const timeDisplay = response.executionTime ? ` (${response.executionTime}ms)` : '';

  if (response.error && !response.output && !response.images?.length) {
    return `⚠️ ${langDisplay}${engineDisplay} 代码执行出错`;
  }

  // 计算输出行数
  const outputLines = response.output?.split('\n').filter(l => l.trim()).length || 0;
  const imageCount = response.images?.length || 0;

  // 构建结果描述
  const parts: string[] = [];
  if (outputLines > 0) {
    parts.push(`输出 ${outputLines} 行`);
  }
  if (imageCount > 0) {
    parts.push(`生成 ${imageCount} 张图表`);
  }

  const resultDesc = parts.length > 0 ? parts.join('，') : '无输出';

  return `✅ ${langDisplay}${engineDisplay} 代码执行完成${timeDisplay}，${resultDesc}`;
}

/**
 * 获取支持的语言列表
 */
export function getSupportedLanguages(): string[] {
  return Object.keys(LANGUAGE_MAP);
}