/**
 * 工具执行器
 * 接收后端的 tool_call 事件，执行本地工具，返回结果
 */
import * as vscode from 'vscode';
import * as path from 'path';
import * as os from 'os';
import * as fs from 'fs';
import { readFileContent, readDirectory } from '../utils/readFiles';
import { createOrOverwriteFile } from '../utils/createFiles';
import { generateVCD, checkIverilogAvailable } from '../utils/iverilogRunner';
import {
  submitToolResult,
  createSuccessResult,
  createBusinessErrorResult,
  createSystemErrorResult
} from './apiClient';
import type {
  ToolCallRequest,
  ToolName,
  FileReadArgs,
  FileWriteArgs,
  FileListArgs,
  SyntaxCheckArgs,
  SimulationArgs,
  WaveformSummaryArgs
} from '../types/api';

/**
 * 工具执行器上下文
 */
export interface ToolExecutorContext {
  /** 扩展路径（用于 iverilog） */
  extensionPath: string;
  /** 工作区路径 */
  workspacePath: string;
}

/**
 * 执行工具调用
 * @param request 工具调用请求
 * @param context 执行上下文
 */
export async function executeToolCall(
  request: ToolCallRequest,
  context: ToolExecutorContext
): Promise<void> {
  const toolName = request.params.name as ToolName;
  const args = request.params.arguments;
  const callId = request.id;

  console.log(`[ToolExecutor] 执行工具: ${toolName}, callId=${callId}`, args);

  try {
    let resultText: string;

    switch (toolName) {
      case 'file_read':
        resultText = await executeFileRead(args as unknown as FileReadArgs);
        break;
      case 'file_write':
        resultText = await executeFileWrite(args as unknown as FileWriteArgs);
        break;
      case 'file_list':
        resultText = await executeFileList(args as unknown as FileListArgs);
        break;
      case 'syntax_check':
        resultText = await executeSyntaxCheck(args as unknown as SyntaxCheckArgs, context);
        break;
      case 'simulation':
        resultText = await executeSimulation(args as unknown as SimulationArgs, context);
        break;
      case 'waveform_summary':
        resultText = await executeWaveformSummary(args as unknown as WaveformSummaryArgs);
        break;
      default:
        throw new Error(`未知工具: ${toolName}`);
    }

    // 提交成功结果
    const result = createSuccessResult(callId, resultText);
    await submitToolResult(result);
    console.log(`[ToolExecutor] 工具执行成功: ${toolName}, callId=${callId}`);

  } catch (error) {
    const errorMessage = error instanceof Error ? error.message : '未知错误';
    console.error(`[ToolExecutor] 工具执行失败: ${toolName}, callId=${callId}`, error);

    // 提交错误结果
    const result = createBusinessErrorResult(callId, errorMessage);
    await submitToolResult(result);
  }
}

/**
 * 执行 file_read 工具
 */
async function executeFileRead(args: FileReadArgs): Promise<string> {
  const content = await readFileContent(args.path);
  return content;
}

/**
 * 执行 file_write 工具
 */
async function executeFileWrite(args: FileWriteArgs): Promise<string> {
  await createOrOverwriteFile(args.path, args.content);
  return `文件已写入: ${args.path}`;
}

/**
 * 执行 file_list 工具
 */
async function executeFileList(args: FileListArgs): Promise<string> {
  const dirPath = args.path || '.';
  const extensions = args.extension ? [args.extension] : undefined;

  const files = await readDirectory(dirPath, extensions);
  const fileList = files.map(f => f.path).join('\n');

  return fileList || '（目录为空）';
}

/**
 * 执行 syntax_check 工具
 * 将代码写入临时文件，调用 iverilog 检查语法
 */
async function executeSyntaxCheck(
  args: SyntaxCheckArgs,
  context: ToolExecutorContext
): Promise<string> {
  // 检查 iverilog 是否可用
  const iverilogCheck = await checkIverilogAvailable(context.extensionPath);
  if (!iverilogCheck.available) {
    throw new Error(`iverilog 不可用: ${iverilogCheck.message}`);
  }

  // 创建临时文件
  const tempDir = os.tmpdir();
  const tempFile = path.join(tempDir, `iccoder_syntax_${Date.now()}.v`);

  try {
    // 写入代码到临时文件
    fs.writeFileSync(tempFile, args.code, 'utf-8');

    // 调用 iverilog 进行语法检查
    const { spawn } = require('child_process');
    const iverilogPath = getIverilogPath(context.extensionPath);

    return new Promise((resolve, reject) => {
      const child = spawn(iverilogPath, ['-t', 'null', tempFile], {
        cwd: tempDir,
        env: {
          ...process.env,
          IVERILOG_ROOT: path.join(context.extensionPath, 'tools', 'iverilog')
        }
      });

      let stdout = '';
      let stderr = '';

      child.stdout.on('data', (data: Buffer) => {
        stdout += data.toString();
      });

      child.stderr.on('data', (data: Buffer) => {
        stderr += data.toString();
      });

      child.on('close', (code: number) => {
        // 清理临时文件
        try {
          fs.unlinkSync(tempFile);
        } catch (e) {
          // 忽略清理错误
        }

        if (code === 0) {
          resolve('语法检查通过，无错误。');
        } else {
          resolve(`语法检查发现错误:\n${stderr || stdout}`);
        }
      });

      child.on('error', (error: Error) => {
        try {
          fs.unlinkSync(tempFile);
        } catch (e) {
          // 忽略清理错误
        }
        reject(error);
      });
    });

  } catch (error) {
    // 确保清理临时文件
    try {
      fs.unlinkSync(tempFile);
    } catch (e) {
      // 忽略
    }
    throw error;
  }
}

/**
 * 执行 simulation 工具
 */
async function executeSimulation(
  args: SimulationArgs,
  context: ToolExecutorContext
): Promise<string> {
  // 获取工作区路径
  const workspaceFolders = vscode.workspace.workspaceFolders;
  if (!workspaceFolders || workspaceFolders.length === 0) {
    throw new Error('请先打开一个工作区');
  }

  const projectPath = workspaceFolders[0].uri.fsPath;

  // 调用现有的 generateVCD 函数
  const result = await generateVCD(projectPath, context.extensionPath);

  if (result.success) {
    let message = result.message;
    if (result.stdout) {
      message += `\n\n仿真输出:\n${result.stdout}`;
    }
    return message;
  } else {
    let errorMessage = result.message;
    if (result.stderr) {
      errorMessage += `\n\n错误输出:\n${result.stderr}`;
    }
    throw new Error(errorMessage);
  }
}

/**
 * 执行 waveform_summary 工具
 * TODO: 实现 VCD 波形分析
 */
async function executeWaveformSummary(args: WaveformSummaryArgs): Promise<string> {
  // TODO: 使用 vcdrom/vcd-stream 解析 VCD 文件
  // 目前返回一个占位响应
  return `波形分析功能暂未实现。\n请求参数:\n- VCD文件: ${args.vcdPath}\n- 信号: ${args.signals}\n- 检查点: ${args.checkpoints || '无'}`;
}

/**
 * 获取 iverilog 路径
 */
function getIverilogPath(extensionPath: string): string {
  const platform = process.platform;
  if (platform === 'win32') {
    return path.join(extensionPath, 'tools', 'iverilog', 'bin', 'iverilog.exe');
  } else {
    return path.join(extensionPath, 'tools', 'iverilog', 'bin', 'iverilog');
  }
}

/**
 * 创建工具执行器上下文
 */
export function createToolExecutorContext(extensionPath: string): ToolExecutorContext {
  const workspaceFolders = vscode.workspace.workspaceFolders;
  const workspacePath = workspaceFolders?.[0]?.uri.fsPath || '';

  return {
    extensionPath,
    workspacePath
  };
}