import * as fs from "fs";
import * as path from "path";
import { expandPath } from "./securityEnhanced";

export type Runtime = "python" | "node" | "bash" | "pwsh" | "powershell" | "cmd" | "java" | "ruby" | "go" | "rust" | "unknown";

export interface RuntimeInfo {
  name: Runtime;
  executable: string;
  extension: string;
}

const RUNTIME_MAP: Record<string, RuntimeInfo> = {
  ".py": { name: "python", executable: "python3", extension: ".py" },
  ".js": { name: "node", executable: "node", extension: ".js" },
  ".ts": { name: "node", executable: "node", extension: ".ts" },
  ".bash": { name: "bash", executable: "bash", extension: ".bash" },
  ".sh": { name: "bash", executable: "bash", extension: ".sh" },
  ".ps1": { name: "pwsh", executable: "pwsh", extension: ".ps1" },
  ".psm1": { name: "pwsh", executable: "pwsh", extension: ".psm1" },
  ".psd1": { name: "pwsh", executable: "pwsh", extension: ".psd1" },
  ".java": { name: "java", executable: "java", extension: ".java" },
  ".rb": { name: "ruby", executable: "ruby", extension: ".rb" },
  ".go": { name: "go", executable: "go", extension: ".go" },
  ".rs": { name: "rust", executable: "rustc", extension: ".rs" },
};

/**
 * Detect runtime language from a file extension.
 */
export function detectRuntime(filePath: string): RuntimeInfo {
  const ext = path.extname(filePath).toLowerCase();
  const info = RUNTIME_MAP[ext];
  if (info) return info;

  // Fallback: check shebang
  try {
    const content = fs.readFileSync(expandPath(filePath), "utf8");
    const shebang = content.split("\n")[0];
    if (shebang.startsWith("#!/bin/bash") || shebang.startsWith("#!/bin/sh")) return { name: "bash", executable: "bash", extension: ext };
    if (shebang.startsWith("#!/usr/bin/env python")) return { name: "python", executable: "python3", extension: ext };
    if (shebang.startsWith("#!/usr/bin/env node")) return { name: "node", executable: "node", extension: ext };
    if (shebang.startsWith("#!/usr/bin/env pwsh")) return { name: "pwsh", executable: "pwsh", extension: ext };
  } catch { /* ignore */ }

  return { name: "unknown", executable: "unknown", extension: ext };
}

/**
 * Resolve the full path of an executable in PATH.
 */
export function which(executable: string): string | null {
  const which = require("child_process").execSync;
  try {
    const platform = require("os").platform();
    const cmd = platform === "win32" ? `where ${executable}` : `which ${executable}`;
    const result = which(cmd, { encoding: "utf8", timeout: 3000 }).trim();
    const lines = result.split("\n").filter((l: string) => l.trim());
    return lines.length > 0 ? lines[lines.length - 1].trim() : null;
  } catch {
    return null;
  }
}

import * as fs from "fs";
import * as path from "path";
import { expandPath } from "./securityEnhanced";

export type Runtime = "python" | "node" | "bash" | "pwsh" | "powershell" | "cmd" | "java" | "ruby" | "go" | "rust" | "unknown";

export interface RuntimeInfo {
  name: Runtime;
  executable: string;
  extension: string;
}

const RUNTIME_MAP: Record<string, RuntimeInfo> = {
  ".py": { name: "python", executable: "python3", extension: ".py" },
  ".js": { name: "node", executable: "node", extension: ".js" },
  ".ts": { name: "node", executable: "node", extension: ".ts" },
  ".bash": { name: "bash", executable: "bash", extension: ".bash" },
  ".sh": { name: "bash", executable: "bash", extension: ".sh" },
  ".ps1": { name: "pwsh", executable: "pwsh", extension: ".ps1" },
  ".psm1": { name: "pwsh", executable: "pwsh", extension: ".psm1" },
  ".psd1": { name: "pwsh", executable: "pwsh", extension: ".psd1" },
  ".java": { name: "java", executable: "java", extension: ".java" },
  ".rb": { name: "ruby", executable: "ruby", extension: ".rb" },
  ".go": { name: "go", executable: "go", extension: ".go" },
  ".rs": { name: "rust", executable: "rustc", extension: ".rs" },
};

/**
 * Detect runtime language from a file extension.
 */
export function detectRuntime(filePath: string): RuntimeInfo {
  const ext = path.extname(filePath).toLowerCase();
  const info = RUNTIME_MAP[ext];
  if (info) return info;

  // Fallback: check shebang
  try {
    const content = fs.readFileSync(expandPath(filePath), "utf8");
    const shebang = content.split("\n")[0];
    if (shebang.startsWith("#!/bin/bash") || shebang.startsWith("#!/bin/sh")) return { name: "bash", executable: "bash", extension: ext };
    if (shebang.startsWith("#!/usr/bin/env python")) return { name: "python", executable: "python3", extension: ext };
    if (shebang.startsWith("#!/usr/bin/env node")) return { name: "node", executable: "node", extension: ext };
    if (shebang.startsWith("#!/usr/bin/env pwsh")) return { name: "pwsh", executable: "pwsh", extension: ext };
  } catch { /* ignore */ }

  return { name: "unknown", executable: "unknown", extension: ext };
}

/**
 * Resolve the full path of an executable in PATH.
 */
export function which(executable: string): string | null {
  const which = require("child_process").execSync;
  try {
    const platform = require("os").platform();
    const cmd = platform === "win32" ? `where ${executable}` : `which ${executable}`;
    const result = which(cmd, { encoding: "utf8", timeout: 3000 }).trim();
    const lines = result.split("\n").filter((l: string) => l.trim());
    return lines.length > 0 ? lines[lines.length - 1].trim() : null;
  } catch {
    return null;
  }
}