"use strict";

const fs = require("fs");
const path = require("path");
const minimist = require("minimist");
const low = require("lowdb");
const Queue = require('better-queue');
const FileSync = require("lowdb/adapters/FileSync");

const chokidar = require("chokidar");
const hbjs = require("handbrake-js");

const args = minimist(process.argv.slice(2), {
  alias: {
    h: "help",
    v: "version",
    c: "config",
    i: "ignoreInitial",
    t: "test"
  }
});

const version = () => {
  const pkg = require('./package.json');
  return console.log(pkg.version);
}

const help = () => {
  let message = `Usage:
\tnpm run movies
\tnpm run tvshows
\tnpm run pr0n
\tnpm run all
\tnpm run help
\tnpm run version\n`
  return console.log(message);
}

String.prototype.toTitleCase = function() {
  var i, j, str, lowers, uppers;
  str = this.replace(/([^\W_]+[^\s-]*) */g, function(txt) {
    return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();
  });
  // Certain minor words should be left lowercase unless
  // they are the first or last words in the string
  lowers = ['A', 'An', 'The', 'And', 'But', 'Or', 'For', 'Nor', 'As', 'At',
  'By', 'For', 'From', 'In', 'Into', 'Near', 'Of', 'On', 'Onto', 'To', 'With'];
  for (i = 0, j = lowers.length; i < j; i++)
    str = str.replace(new RegExp('\\s' + lowers[i] + '\\s', 'g'),
      function(txt) {
        return txt.toLowerCase();
      });
  // Certain words such as initialisms or acronyms should be left uppercase
  uppers = ['Id', 'Tv'];
  for (i = 0, j = uppers.length; i < j; i++)
    str = str.replace(new RegExp('\\b' + uppers[i] + '\\b', 'g'),
      uppers[i].toUpperCase());
  return str;
};

// get the db from the path
const getDbForDir = (dir, opts) => {
  let options = opts || Object.assign({}, defaults, paths[dir]); // baseline the options
  let adapter = new FileSync(options.database); // init the db adapter
  let db = low(adapter);  // connect the db
  return db;
};

// find a file in the db
const findFile = (db, file) => {
  return db.get('files').find({ input:file }).value();	// does it already exist?
};

// set a file in the db
const setFile = (db, file, payload) => {
  if (!payload && typeof file === 'object')
    return db.get('files').push(file).write();
  return db.get('files').find({ input: file }).assign(payload).write();
};

// remove a file from the db
const removeFile = (db, file) => {
  return db.get('files').remove({ input: file }).write(); // remove file from database
};

// write process output
const processOutput = (str) => {
  process.stdout.clearLine();
  process.stdout.cursorTo(0);
  process.stdout.write(str);
};

// spawn a handbrake
const processWithHandbrake = (input, output, preset) => {
  return new Promise((resolve, reject) => {
    const filename = path.basename(input);
    hbjs.spawn({
    	input: input,
    	output: output,
    	preset: preset
    }).on('start', (err) => {
      processOutput(` --> processing "${filename}" to "${output}" with "${preset}"`);
    }).on('error', (err) => {
      processOutput(` --> processing ${output} error: ${err.message || err}.\n`);
      reject(err);
    }).on('progress', (progress) => {
      processOutput(` --> processing ${output} - ${progress.percentComplete}%, ETA: ${progress.eta}`);
    }).on('cancelled', () => {
      processOutput(` --> processing ${output} cancelled\n`);
      reject(new Error(`Processing ${output} cancelled`));
    }).on('complete', () => {
      processOutput(` --> processing ${output} complete\n`);
      resolve(true);
    });
  });
};

const processFile = async (file) => {
  let db,
    options,
    preset = 'Fast 1080p30',
    clean = {
      '.': ' '
    },
    ext = 'm4v',
    filename = path.parse(file).name,
    input = file,
    output = filename,
    titlecase = false,
    folder = false,
    destination = '';

  // determine the presets and clean object
  for (let i = 0, l = dirs.length; i < l; i++) {
    let dir = dirs[i]; // pointer to the dir
    if (file && dir && file.indexOf(dir) > -1) {  // is this in this path?
      options = Object.assign({}, defaults, paths[dir]); // baseline the options
      db = getDbForDir(dir, options); // init the db connection
      let found = findFile(db, file);	// does it already exist?
      if (found && found.status && found.status === 'success') {	// was it already processed?
        //console.log(`File ${file} has already been successfully processed.`);
        return false;	// break this loop
      } else if (!found) {	// was it found?
        processOutput(`-> ${path.basename(file)} [processing]`);
        setFile(db, { input:file, output:'', status:'', date:new Date() }); // push onto the list an entry
      } else {
        processOutput(`-> ${path.basename(file)} [re-processing]`);
        setFile(db, file, { status:'', date:new Date() }); // set the status to blank
      }
      preset = options.preset; // apply the specifics ...
      clean = options.clean; // ...
      ext = options.ext; // ...
      titlecase = !!options.titlecase; // ...
      folder = !!options.folder; // ...
      destination = options.destination; // ...
      break; // break the loop
    }
  }
  // clean the output name
  let cleanKeys = Object.keys(clean);
  for (let c in cleanKeys) {
    let key = cleanKeys[c];
    let val = clean[key];
    let re = new RegExp(key, 'gi');
    output = output.replace(re, val);
  }
  // baseline the output name
  output = output.trim(); // trim the whitespace
  output = output.replace(/(\d{4})$/, `($1)`); // if there is a date at the end wrap it
  // do we have a sub folder option?
  if (folder) {
    let match = output.match(/^(.*?)?\./gm); // get the name for the file before the first .
    folder = (match && match.length > 0) ? match[0].slice(0, -1) : false; // get just the stuff before the dot ... or false
  }
  // do we have title case enabled?
  if (options.titlecase) output = output.toTitleCase();  // titlecase that string
  // baseline the target
  let target = destination + ((folder) ? '/' + folder : ''); // setup the target location
  output = target + '/' + output + '.' + ext; // update the new name
  // do we already have an existing output that matches?
  if (fs.existsSync(output)) {
    processOutput(`-> ${path.basename(file)} [skipping ... already processed]\n`);
    setFile(db, file, { output: output, status: 'success', date:new Date() }); // update database with status
    return false;
  } else {
    processOutput('\n'); // send a new line
  }
  // update database with output name
  setFile(db, file, { output: output });
  // create parent if required
  if (target && !fs.existsSync(target)) {
    console.log(' --> creating parent directory:', target);
    fs.mkdirSync(target, {
      recursive: true
    });
  }
  // spawn handbrake
  if (!test) {
    try {
      await processWithHandbrake(input, output, preset);
      setFile(db, file, { status: 'success', date:new Date() }); // update database with status
    } catch (err) {
      setFile(db, file, { status: 'failure', date:new Date() }); 	// update database with status
    }
  }
  return true; // when complete return true
};

// cleanup removes from the db
const cleanup = (file) => {
  let db;
  for (let i = 0, l = dirs.length; i < l; i++) {
    let dir = dirs[i]; // pointer to the dir
    if (file && dir && file.indexOf(dir) > -1) {  // is this in this path?
      db = getDbForDir(dir); // init the db connection
      removeFile(db, file); // remove file form database
    }
  }
};

// handle args
if (args.version) return version(); // show version
if (args.help || !args.config) return help(); // show help
const ignoreInitial = (args.hasOwnProperty('ignoreInitial')) ? args.ignoreInitial : false;  // ignore initial files
const test = (args.hasOwnProperty('test')) ? args.test : false; // do a dry run ... just log

// get our paths
const paths = require(args.config);

// init our defaults
const defaults = {
  "preset": "Fast 1080p30",
  "clean": {},
  "titlecase": false,
  "folder": false,
  "database": "data/db.json"
}

// setup watcher options
const opts = {
  ignored: /(^|[\/\\])\..|([s|S]ample\.*)/,
  ignoreInitial: ignoreInitial,
  persistent: true,
  usePolling: true,
  interval: 10000,
  depth: 1,
  awaitWriteFinish: {
    stabilityThreshold: 3000,
    pollInterval: 1000
  },
  ignorePermissionErrors: false,
  atomic: true
};

// parse the paths to dirs
const dirs = Object.keys(paths);

// initialize watches and db then start the watcher
const main = () => {
  var queue = new Queue((input,cb) => {  // init the queue
    let result = processFile(input); // process the queue
    cb(null,result);
  });
  var watches = []; // array of things to watch
  for (let d in dirs) { // loop the dirs
    let dir = dirs[d]; // pointer
    let options = Object.assign({}, defaults, paths[dir]); // baseline the options
    let db = getDbForDir(dir);
    db.defaults({ files: [] }).write(); // init the database
    for (let e in options.exts) { // loop the exts to watch
      let ext = options.exts[e]; // alias the ext
      watches.push(`${dir}/**/*.${ext}`); // push the watch
    }
  }
  const watcher = chokidar.watch(watches, opts); // init our watcher
  console.log('Watching', watches);
  watcher.on('add', async (file) => { // when a new file is added ...
    queue.push(file); // push the file onto the queue to be processed
  }).on('change', (file) => { // when a file changes ...
    console.log(` -> ${file} has been changed`);
  }).on('unlink', async (file) => { // when a file is removed ...
    console.log(` -> ${file} has been removed`);
    cleanup(file);
  }).on('error', (error) => { // on errors ..
    console.error(` -> Error: ${error.message || error}`);
  });
}

main();