/// <reference types="bun-types" />

type CiTestPlan = {
  isolatedTestTargets: string[]
  isolatedModuleMockFiles: string[]
  sharedTestFiles: string[]
}

const TEST_ROOTS = ["bin", "script", "src"] as const
const MODULE_MOCK_PATTERN = "mock.module("

async function collectTestFiles(rootDirectory: string): Promise<string[]> {
  const testFiles: string[] = []

  for (const testRoot of TEST_ROOTS) {
    const glob = new Bun.Glob("**/*.test.ts")

    for await (const testFile of glob.scan({ cwd: `${rootDirectory}/${testRoot}` })) {
      testFiles.push(`${testRoot}/${testFile}`)
    }
  }

  return testFiles.sort((left, right) => left.localeCompare(right))
}

async function usesModuleMock(rootDirectory: string, testFile: string): Promise<boolean> {
  const testContents = await Bun.file(`${rootDirectory}/${testFile}`).text()
  return testContents.includes(MODULE_MOCK_PATTERN)
}

function toIsolatedTarget(testFile: string): string {
  const pathSegments = testFile.split("/")

  if (pathSegments.length <= 3) {
    return testFile
  }

  return pathSegments.slice(0, -1).join("/")
}

function isCoveredByTarget(testFile: string, isolatedTarget: string): boolean {
  return testFile === isolatedTarget || testFile.startsWith(`${isolatedTarget}/`)
}

function collapseNestedTargets(isolatedTargets: string[]): string[] {
  return isolatedTargets.filter((isolatedTarget) => {
    return !isolatedTargets.some((otherTarget) => {
      return otherTarget !== isolatedTarget && isolatedTarget.startsWith(`${otherTarget}/`)
    })
  })
}

export async function createCiTestPlan(rootDirectory: string = process.cwd()): Promise<CiTestPlan> {
  const allTestFiles = await collectTestFiles(rootDirectory)
  const isolatedModuleMockFiles: string[] = []

  for (const testFile of allTestFiles) {
    if (await usesModuleMock(rootDirectory, testFile)) {
      isolatedModuleMockFiles.push(testFile)
    }
  }

  const isolatedTestTargets = collapseNestedTargets(
    Array.from(new Set(isolatedModuleMockFiles.map((testFile) => toIsolatedTarget(testFile)))).sort((left, right) =>
      left.localeCompare(right),
    ),
  )
  const sharedTestFiles = allTestFiles.filter((testFile) => {
    return !isolatedTestTargets.some((isolatedTarget) => isCoveredByTarget(testFile, isolatedTarget))
  })

  return {
    isolatedTestTargets,
    isolatedModuleMockFiles,
    sharedTestFiles,
  }
}

async function runBunTest(testFiles: string[], label: string): Promise<void> {
  if (testFiles.length === 0) {
    return
  }

  console.log(`::group::${label}`)
  
  // For directory paths, exclude _auc* directories which are separate isolated targets
  const args = testFiles.map(tf => {
    if (tf.includes('/') && !tf.endsWith('.test.ts')) {
      // It's a directory path, add negation glob
      return [tf, '!_auc-*/**/*.test.ts']
    }
    return tf
  }).flat()
  
  const command = ["bun", "test", ...args]
  const spawnedProcess = Bun.spawn(command, {
    cwd: process.cwd(),
    stdin: "inherit",
    stdout: "inherit",
    stderr: "inherit",
  })
  const exitCode = await spawnedProcess.exited
  console.log("::endgroup::")

  if (exitCode !== 0) {
    throw new Error(`Command failed: ${command.join(" ")}`)
  }
}

async function main(): Promise<void> {
  const ciTestPlan = await createCiTestPlan()

  console.log(
    `Detected ${ciTestPlan.isolatedModuleMockFiles.length} mock.module() test files, ${ciTestPlan.isolatedTestTargets.length} isolated targets, and ${ciTestPlan.sharedTestFiles.length} shared test files.`,
  )

  for (const isolatedTestTarget of ciTestPlan.isolatedTestTargets) {
    await runBunTest([isolatedTestTarget], `Isolated ${isolatedTestTarget}`)
  }

  await runBunTest(ciTestPlan.sharedTestFiles, "Shared Bun test suite")
}

export const moduleMockPattern = MODULE_MOCK_PATTERN
export const testRoots = TEST_ROOTS

if (process.argv.includes("--print-plan")) {
  const ciTestPlan = await createCiTestPlan()
  console.log(JSON.stringify(ciTestPlan, null, 2))
} else if (import.meta.main) {
  try {
    await main()
  } catch (error) {
    const message = error instanceof Error ? error.message : String(error)
    console.error(message)
    process.exit(1)
  }
}