import { execFileSync } from 'node:child_process'
import {
	existsSync,
	mkdirSync,
	readdirSync,
	rmSync,
	statSync,
} from 'node:fs'
import { delimiter, join, relative } from 'node:path'

const rootDir = process.cwd()

const protoRoot = 'proto'
const genRoot = 'gen'

const isWindows = process.platform === 'win32'

const tsProtoBinDir = join(rootDir, 'node_modules', '.bin')

const tsProtoPlugin = isWindows
	? join(tsProtoBinDir, 'protoc-gen-ts_proto.cmd')
	: join(tsProtoBinDir, 'protoc-gen-ts_proto')

function toUnixPath(path) {
	return path.replaceAll('\\', '/')
}

function collectProtoFiles(dir) {
	const files = []

	for (const entry of readdirSync(dir)) {
		const fullPath = join(dir, entry)
		const stat = statSync(fullPath)

		if (stat.isDirectory()) {
			files.push(...collectProtoFiles(fullPath))
			continue
		}

		if (entry.endsWith('.proto')) {
			files.push(toUnixPath(relative(rootDir, fullPath)))
		}
	}

	return files
}

if (!existsSync(protoRoot)) {
	console.error(`Proto directory not found: ${protoRoot}`)
	process.exit(1)
}

if (!existsSync(tsProtoPlugin)) {
	console.error(`ts-proto plugin not found: ${tsProtoPlugin}`)
	console.error('Run: yarn add -D ts-proto')
	process.exit(1)
}

const protoFiles = collectProtoFiles(protoRoot)

if (protoFiles.length === 0) {
	console.error('No .proto files found.')
	process.exit(1)
}

rmSync(genRoot, {
	recursive: true,
	force: true,
})

mkdirSync(genRoot, {
	recursive: true,
})

const env = {
	...process.env,
	PATH: `${tsProtoBinDir}${delimiter}${process.env.PATH ?? ''}`,
	Path: `${tsProtoBinDir}${delimiter}${process.env.Path ?? ''}`,
}

execFileSync(
	'protoc',
	[
		'-I',
		protoRoot,

		'--ts_proto_out',
		genRoot,

		'--ts_proto_opt',
		'nestJs=true,package=omit',

		...protoFiles,
	],
	{
		cwd: rootDir,
		stdio: 'inherit',
		env,
	},
)