/**
 * CppProjectDetector - Detects C++ project structure and toolchain
 * DD §15. detect→CppDetectOutput.
 *
 * @module packages/toolchain-cpp/src/detect/CppProjectDetector
 */

import { existsSync, readFileSync } from 'fs'
import { join } from 'path'

export interface CppDetectOutput {
  project_type: 'cmake' | 'make' | 'unknown'
  has_cmake: boolean
  has_make: boolean
  has_ninja: boolean
  has_compiler: boolean
  compiler_version?: string
  build_dir?: string
  source_files: string[]
  compile_commands?: string
}

export class CppProjectDetector {
  private project_root: string

  constructor(project_root: string) {
    this.project_root = project_root
  }

  detect(): CppDetectOutput {
    const result: CppDetectOutput = {
      project_type: 'unknown',
      has_cmake: false,
      has_make: false,
      has_ninja: false,
      has_compiler: false,
      source_files: []
    }

    // Detect project type
    if (existsSync(join(this.project_root, 'CMakeLists.txt'))) {
      result.project_type = 'cmake'
      result.has_cmake = true
    } else if (existsSync(join(this.project_root, 'Makefile'))) {
      result.project_type = 'make'
      result.has_make = true
    }

    // Check for compile_commands.json
    const cc_path = join(this.project_root, 'build', 'compile_commands.json')
    if (existsSync(cc_path)) {
      result.compile_commands = cc_path
    }

    // Check toolchain
    result.has_ninja = this.command_exists('ninja')
    result.has_compiler = this.command_exists('g++') || this.command_exists('clang++')

    // Find source files
    result.source_files = this.find_cpp_sources()

    return result
  }

  private command_exists(cmd: string): boolean {
    // Simplified check
    return existsSync(`/usr/bin/${cmd}`) || existsSync(`/usr/local/bin/${cmd}`)
  }

  private find_cpp_sources(): string[] {
    // Would recursively find .cpp/.cc/.cxx/.h/.hpp files
    return []
  }
}
