import { access, stat } from 'node:fs/promises'
import { constants } from 'node:fs'
import { homedir, platform } from 'node:os'
import { delimiter, join } from 'node:path'
import { execFile } from 'node:child_process'
import { createSpine38ImportOptions } from './spine38-project.mjs'

const SUPPORTED_VERSIONS = new Set(['3.8', '4.0', '4.1', '4.2', '4.3'])

async function executable(path) {
  if (!path) return false
  try {
    await access(path, platform() === 'win32' ? constants.F_OK : constants.X_OK)
    return true
  } catch {
    return false
  }
}

export async function findSpineExecutable() {
  const candidates = []
  if (process.env.SPINE_EXECUTABLE) candidates.push(process.env.SPINE_EXECUTABLE)
  if (platform() === 'darwin') {
    candidates.push(
      '/Applications/Spine.app/Contents/MacOS/Spine',
      join(homedir(), 'Applications/Spine.app/Contents/MacOS/Spine'),
    )
  } else if (platform() === 'win32') {
    const programFiles = [process.env.ProgramFiles, process.env['ProgramFiles(x86)'], process.env.LOCALAPPDATA].filter(Boolean)
    for (const root of programFiles) {
      candidates.push(
        join(root, 'Spine', 'Spine.com'),
        join(root, 'Esoteric Software', 'Spine', 'Spine.com'),
        join(root, 'Programs', 'Spine', 'Spine.com'),
      )
    }
    // 支持用户将 Spine 安装在自定义目录并把该目录加入 Windows PATH。
    for (const root of String(process.env.Path || process.env.PATH || '').split(delimiter).filter(Boolean)) {
      candidates.push(join(root.replace(/^"|"$/g, ''), 'Spine.com'))
    }
  } else {
    candidates.push('/opt/Spine/Spine.sh', join(homedir(), 'Spine/Spine.sh'), '/usr/local/bin/Spine', '/usr/bin/Spine')
  }
  for (const candidate of candidates) if (await executable(candidate)) return candidate
  return null
}

export function normalizeSpineVersion(value) {
  const match = /^(3\.8|4\.[0-3])(?:\.\d+)?$/.exec(String(value || '').trim())
  if (!match || !SUPPORTED_VERSIONS.has(match[1])) throw new Error(`不支持的 Spine 版本：${value}`)
  return match[1]
}

function run(executablePath, args, { cwd, timeoutMs = 180000 } = {}) {
  return new Promise((resolve, reject) => {
    execFile(executablePath, args, { cwd, timeout: timeoutMs, windowsHide: true, maxBuffer: 4 * 1024 * 1024 }, (error, stdout, stderr) => {
      if (error) {
        const details = [stdout, stderr, error.message]
          .filter(Boolean)
          .join('\n')
          .replace(/^Licensed to:.*$/gim, 'Spine 授权信息已隐藏')
          .trim()
        reject(new Error(details || 'Spine 命令执行失败'))
        return
      }
      resolve({ stdout, stderr })
    })
  })
}

export async function importSpineProject({ executablePath, inputPath, outputPath, projectName, spineVersion, workspaceRoot }) {
  const version = normalizeSpineVersion(spineVersion)
  const editorVersion = `${version}.xx`
  const importOptions = version === '3.8'
    ? createSpine38ImportOptions({ workspaceRoot, inputPath, outputPath })
    : { inputPath, outputPath }
  const result = await run(executablePath, [
    '--update', editorVersion,
    '--input', importOptions.inputPath,
    '--output', importOptions.outputPath,
    '--import', projectName,
  ], { cwd: importOptions.cwd })
  const output = await stat(outputPath).catch(() => null)
  if (!output?.isFile() || output.size === 0) throw new Error('Spine 未生成有效的工程文件')
  const detected = /Starting:\s+Spine\s+([0-9.]+)/i.exec(`${result.stdout}\n${result.stderr}`)?.[1] || editorVersion
  return { ...result, editorVersion: detected, size: output.size }
}