import {parse, stringify} from 'yaml';

(async () => {
  const serviceName = prompt('Service name? (This is used by the router to determine the route prefix)')?.replace('-service', '');
  if (!serviceName) return;
  type permissionShorts = 'r' | 'w' | 'x' | 'n';
  type permissionNames = 'read' | 'write' | 'execute' | 'run' | 'net';

  const getPermissionByNameOrShort = (name: permissionNames | permissionShorts | string) => {
    switch (name) {
      case "read":
      case "r":
        return {
          name: 'read',
          denoPerm: '--allow-read'
        };
      case "write":
      case "w":
        return {
          name: 'write',
          denoPerm: '--allow-write'
        };
      case "execute":
      case "run":
      case "x":
        return {
          name: 'run',
          denoPerm: '--allow-run'
        };
      case "net":
      case "n":
        return {
          name: 'net',
          denoPerm: '--allow-net'
        };
      default:
        return {
          name: 'custom-' + name,
          denoPerm: '--allow-' + name
        }
    }
  }

  const perms = [];

  if (Deno.args[0]) {
    const permShort = Deno.args[0].split('') as permissionShorts[];
    for (const short of permShort) {
      perms.push(getPermissionByNameOrShort(short));
    }
  } else if (confirm('Permissions not specified, would you like to add specific permissions?')) {
    let permsPrompt: string | null = '';
    while (!permsPrompt) {
      permsPrompt = prompt('Please enter the permission short code or names of permissions you would like');
      if (!permsPrompt) continue
      let permNames;
      if (permsPrompt?.match(' ')) {
        permNames = permsPrompt.split(' ');
      } else {
        permNames = permsPrompt.split('');
      }

      for (const perm of permNames) {
        perms.push(getPermissionByNameOrShort(perm));
      }
    }
  }

  console.log(`Service will run with following permissions: ${perms.map(p => p.name).join()}`);
  if (!perms.find(p => p.name === 'net')) {
    if (!confirm('Service does not have permissions to "net", is this correct?'))
      perms.push(getPermissionByNameOrShort('net'));
  }
  
  const serviceFile = `./${serviceName}-service/`;
  let port;
  await Deno.mkdir(serviceFile);
  port = await getAvailablePort();
  if (perms.find(p => p.name === 'net')) {
    await Deno.writeTextFile(serviceFile + 'port', port)
  }
  await Deno.writeTextFile(serviceFile + 'main.ts', `
import { CGGService } from 'cgg/Application.ts';
import { Router } from 'oak';

const app = new CGGService({ prefix: '/${serviceName}' });

app.route(new Router()
  .get('/', ctx => ctx.response.body = '${serviceName} service')
);

app.start();
console.log('${serviceName} service running on ' + Deno.args.at(0));
`);
  await Deno.writeTextFile(serviceFile + 'perms', perms.map(p => p.denoPerm).join('\n'));
  await Deno.writeTextFile(serviceFile + 'prefix', serviceName);
  
  if (confirm('Containerize this service?')) {
    await Deno.writeTextFile(serviceFile + 'Dockerfile', `
FROM denoland/deno:1.33.2
${port ? 'EXPOSE ' + port : ''}

WORKDIR /${serviceName}

ADD ${serviceFile} .
ADD ./deno.jsonc .
ADD ./secrets.json .
ADD ./key.txt .
ADD ./common ./common
ADD ./lib ./lib
ADD ./middleware ./middleware

CMD ["run", "${perms.join('", "')}", main.ts${port ? `, "${port}"` : ''}]
`);

    const dockerCompose: any = parse(await Deno.readTextFile('./docker-compose.yml'));
    dockerCompose['services'][serviceName] = {
      build: {
        context: "./", 
        dockerfile: serviceFile + 'Dockerfile'
      }
    }

    await Deno.writeTextFile('./docker-compose.yml', stringify(dockerCompose))
  }

  if (confirm('Does this service need DB access?'))
    await Deno.writeTextFile(serviceFile + 'data.ts', `
import mongoose from 'mongoose';
import { configDatabase } from 'lib/data.ts';

configDatabase(mongoose);
`)
})();

async function getAvailablePort() {
  let start = 6900;

  const missingPorts = [];
  const takenPorts = [];
  
  for await (const dirEntry of Deno.readDir('.')) {
    if (dirEntry.isFile || !dirEntry.name.includes('-service')) continue;
    const dir = './' + dirEntry.name + '/';
    if (!Array.from(Deno.readDirSync(dir)).find(e => e.name === 'port')) {
      missingPorts.push(dir);
      continue;
    }

    takenPorts.push(Number(await Deno.readTextFile(dir + 'port')));
  }

  takenPorts.sort();

  for (const port of takenPorts) {
    if (start === port) start++;
  }

  for (const missing of missingPorts) {
    Deno.writeTextFile(missing + 'port', start.toString());
    takenPorts.push(start);
    while(takenPorts.includes(start)) start++;
  }

  return start.toString();
}