import assert from 'node:assert/strict'
import fs from 'node:fs'
import os from 'node:os'
import path from 'node:path'

import { test } from 'vitest'

import { appIconCandidates, decodingFileProbe, resolveAppIcon } from './app-icon'

// Regression: a packaged app.asar can contain a TRUNCATED apple-touch-icon.png
// (interrupted electron-builder run, partial copy). Electron's
// BrowserWindow({ icon }) / app.dock.setIcon() decode synchronously and THROW
// on undecodable bytes, which killed the main process inside createWindow()
// and took the app down mid-session. Icon resolution must fail soft: skip a
// candidate that exists but does not decode, exactly like a missing one.

test('resolveAppIcon skips an existing but undecodable candidate', () => {
  // First candidate "exists" (probe says true) but does not decode; second
  // decodes. The resolver must return the second, not the first.
  const probeCalls: string[] = []

  const probe = (p: string) => {
    probeCalls.push(p)

    return p !== '/packaged/app.asar/public/apple-touch-icon.png'
  }

  const picked = resolveAppIcon(
    ['/packaged/app.asar/public/apple-touch-icon.png', '/packaged/app.asar/dist/apple-touch-icon.png'],
    probe
  )

  assert.equal(picked, '/packaged/app.asar/dist/apple-touch-icon.png')
  assert.deepEqual(probeCalls, [
    '/packaged/app.asar/public/apple-touch-icon.png',
    '/packaged/app.asar/dist/apple-touch-icon.png'
  ])
})

test('resolveAppIcon returns undefined when every candidate fails the probe', () => {
  const picked = resolveAppIcon(['/a.png', '/b.ico'], () => false)
  assert.equal(picked, undefined)
})

test('resolveAppIcon returns the first candidate that passes the probe', () => {
  const picked = resolveAppIcon(['/a.png', '/b.png'], () => true)
  assert.equal(picked, '/a.png')
})

test('decodingFileProbe rejects a missing file', () => {
  const missing = path.join(os.tmpdir(), `hermes-icon-missing-${process.pid}.png`)
  assert.equal(decodingFileProbe(missing), false)
})

test('decodingFileProbe rejects an existing but empty (0-byte) file', () => {
  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'hermes-icon-'))
  const empty = path.join(dir, 'apple-touch-icon.png')
  fs.writeFileSync(empty, Buffer.alloc(0))

  try {
    // 0 bytes exist but decode to an empty image — and without electron in
    // the test runtime the require itself fails. Both paths must be false.
    assert.equal(decodingFileProbe(empty), false)
  } finally {
    fs.rmSync(dir, { recursive: true, force: true })
  }
})

test('decodingFileProbe rejects a directory', () => {
  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'hermes-icon-dir-'))

  try {
    assert.equal(decodingFileProbe(dir), false)
  } finally {
    fs.rmSync(dir, { recursive: true, force: true })
  }
})

test('appIconCandidates keeps the documented precedence ladder', () => {
  const mac = appIconCandidates({
    isWindows: false,
    appRoot: '/Applications/Hermes.app/Contents/Resources',
    unpackedPathFor: p => `${p}.unpacked`
  })

  assert.deepEqual(mac, [
    path.join('/Applications/Hermes.app/Contents/Resources', 'public', 'apple-touch-icon.png'),
    path.join('/Applications/Hermes.app/Contents/Resources', 'dist', 'apple-touch-icon.png'),
    path.join('/Applications/Hermes.app/Contents/Resources.unpacked', 'dist', 'apple-touch-icon.png')
  ])

  // Windows prepends the two full-bleed .ico rungs ahead of the PNG ladder.
  const win = appIconCandidates({
    isWindows: true,
    appRoot: 'C:\\app',
    resourcesPath: 'C:\\resources',
    unpackedPathFor: p => `${p}\\unpacked`
  })

  assert.equal(win.length, 5)
  assert.equal(win.filter(c => c.endsWith('.ico')).length, 2)
  assert.equal(
    win[0],
    path.join('C:\\resources', 'icon.ico'),
    'resources/ icon.ico is the highest-precedence Windows rung'
  )
  assert.equal(
    win.filter(c => c.endsWith('apple-touch-icon.png')).length,
    3,
    'all three PNG rungs remain after the ico rungs'
  )
})