import * as pty from 'node-pty'
import { getContainerPath, runCommand } from './utils.js'

import fs from 'fs/promises'

import { randomUUID } from 'crypto'

const stat = path =>
    new Promise(resolve =>
        fs
            .access(path)
            .then(() => resolve(true))
            .catch(() => resolve(false))
    )

const containerIds = new Set()

await cleanContainers()

async function storeContainers() {
    await fs.writeFile('containers-db.local.json', JSON.stringify([...containerIds]))
}

async function cleanContainers() {
    if (!(await stat('containers-db.local.json'))) {
        await storeContainers()
    }

    const raw = JSON.parse(await fs.readFile('containers-db.local.json', 'utf8'))
    await Promise.all(raw.map(id => destroyContainer(id)))
}

async function createContainer(tag) {
    const id = randomUUID().split('-').at(-1)

    await fs.mkdir(getContainerPath('phc', id), { recursive: true })

    await runCommand('docker', [
        'run',
        '-d',
        '--name',
        id,
        '--volume',
        `${getContainerPath('phc', id)}:/project`,
        tag,
        'sleep',
        'infinity',
    ])

    containerIds.add(id)
    await storeContainers()

    await runCommandContainer(id, `echo "echo hello world" > example.sh; chmod +x example.sh`)

    // Example file tree

    await runCommandContainer(id, `mkdir -p /project/src /project/bin`)

    await runCommandContainer(id, `echo 'console.log("Hello from index.js")' > /project/src/index.js`)
    await runCommandContainer(id, `echo 'console.log("Hello from app.js")' > /project/src/app.js`)

    await runCommandContainer(id, `echo 'echo "Hello from script.sh"' > /project/bin/script.sh`)
    await runCommandContainer(id, `chmod +x /project/bin/script.sh`)

    await runCommandContainer(id, `echo 'This is the README file.' > /project/README.md`)
    await runCommandContainer(id, `echo '{"name": "project", "version": "1.0.0"}' > /project/package.json`)

    return id
}

export async function createContainerPty(
    tag,
    options = {
        onExit,
        onData,

        shellCommand: ['/bin/sh'],
    }
) {
    const shellCommand = options.shellCommand ?? ['/bin/sh']
    const { onData, onExit } = options

    const id = await createContainer(tag)

    const container = pty.spawn('docker', ['exec', '-it', '-w', '/project', id, ...shellCommand])

    container.onExit(async e => {
        onExit?.(e)
        await destroyContainer(id)
    })

    container.onData(data => {
        onData?.(data)
    })

    return { id, pty: container }
}

async function destroyContainer(id) {
    await runCommand('docker', ['rm', '-f', id])

    containerIds.delete(id)
    await storeContainers()
}

async function runCommandContainer(uuid, command) {
    return await runCommand('docker', ['exec', '-w', '/project', uuid, '/bin/sh', '-c', command])
}