#!/usr/bin/env babel-node
import path from 'path'
import sqlite from 'sqlite'
import Promise from 'bluebird'
import fs from 'fs-extra'
import {exec} from 'child_process'

const values = require(path.join(__dirname, 'values.json'))
const musicdir = path.resolve(values.directory)

const dbPromise = Promise.resolve()
  .then(() => sqlite.open(path.join(__dirname, values.database), { Promise, cache: true }))
  .then(db => db.migrate())

const readline = require('readline')

// ffprobe -i <file> -show_entries format=duration -v quiet -of csv="p=0"

function filewalker (dir, done) {
  let results = []

  fs.readdir(dir, function (err, list) {
    if (err) return done(err)

    var pending = list.length

    if (!pending) return done(null, results)

    list.forEach(function (file) {
      file = path.resolve(dir, file)

      fs.stat(file, function (err, stat) {
        if (err) return done(err)

        // If directory, execute a recursive call
        if (stat && stat.isDirectory()) {
          //results.push(file)

          filewalker(file, function (err, res) {
            if (err) return done(err)
            results = results.concat(res)
            if (!--pending) done(null, results)
          })
        } else {
          results.push(file)

          if (!--pending) done(null, results)
        }
      })
    })
  })
}

function getFiles (dir) {
  return new Promise((resolve, reject) => {
    filewalker(dir, (err, files) => {
      if (err) return reject(err)
      resolve(files)
    })
  })
}

function promiseExec (cmd, opts) {
  return new Promise((resolve, reject) => {
    exec(cmd, opts, function (err, stdout, stderr) {
      if (err) return reject(err)
      resolve({stdout, stderr})
    })
  })
}

async function getInfos (file) {
  let id3 = await promiseExec(`id3 "${file}"`)
  let prds = id3.stdout.split('\n')
  let data = {}

  // Get id3 tags
  for (let i in prds) {
    let line = prds[i]
    let parts = line.split(': ')
    if (parts.length) {
      let tagtype = parts[0].toLowerCase()
      let tagdata = line.substring(parts[0].length + 2)

      if (tagtype === '') continue
      if (tagtype === 'metadata' && tagdata === 'none found') throw new Error(`No metadata for file "${file}"!`)
      if (tagtype === 'track' || tagtype === 'year') {
        if (tagdata.indexOf('/') !== -1) {
          tagdata = tagdata.split('/')[0]
        }

        tagdata = parseInt(tagdata)
      }

      data[tagtype] = tagdata
    }
  }

  if (!data.title) {
    let parsed = path.parse(file)
    data.title = parsed.name
  }

  // Get track length
  let len = await promiseExec(`ffprobe -i "${file}" -show_entries format=duration -v quiet -of csv="p=0"`)
  len = parseFloat(len.stdout)
  data.duration = len

  return data
}

function parseTitle(data) {
  let tt = data.title

  // Remove []'s from the beginning
  tt = tt.replace(/^\[\w+\]\s?/i, '')

  // Remove "Official Video/Audio" tag
  tt = tt.replace(/\s?(?:[\(\)\[\]])?Official\s?[\w]+(?:[\(\)\[\]])?/i, '')

  // Remove "Audio" tag
  tt = tt.replace(/\s?(?:[\(\)\[\]])Audio?(?:[\(\)\[\]])/i, '')

  // Remove "lyrics" tag
  tt = tt.replace(/\s?(?:[\(\)\[\]])?lyrics?\s?(?:[\w]+)?(?:[\(\)\[\]])?\s?/i, '')

  // Artist / Title split
  let at = tt.split(' - ', 2)
  let artist
  let title

  if (at.length > 1) {
    artist = at[0]
    title = tt.substring(artist.length + 3)
  } else {
    artist = data.artist
    title = tt
  }

  data.title = title
  data.artist = artist

  return data
}

function askAsync (rl, q) {
  return new Promise((resolve, reject) => {
    rl.question(q, resolve)
  })
}

async function interactive (fpath, db) {
  let rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
  })

  console.log('No metadata found for specified file! Interactive mode enabled.\n')

  let pt = path.parse(fpath)
  let track = {
    file: fpath,
    title: pt.name
  }
  let clean = parseTitle(track)

  console.log('Determined Title: ' + clean.title)
  console.log('Determined Artist: ' + clean.artist)

  let newTitle = await askAsync(rl, `Title [${clean.title}] ? `)
  let newArtist = await askAsync(rl, `Artist [${clean.artist}] ? `)

  if (newTitle.trim() !== '')
    track.title = newTitle

  if (newArtist.trim() !== '')
    track.artist = newArtist

  let ensure = await db.get('SELECT * FROM Track WHERE title=? AND artist=?', track.title, track.artist)
  if (ensure) {
    console.error('A track of this description already exists in the database.')
    return rl.close()
  }

  let len = await promiseExec(`ffprobe -i "${track.file}" -show_entries format=duration -v quiet -of csv="p=0"`)
  track.duration = parseFloat(len)

  rl.close()

  return track
}

async function run () {
  let db = await dbPromise

  if (process.argv[2] != null) {
    let filePath = path.resolve(process.argv[2])
    let trackinf

    try {
      trackinf = await getInfos(filePath)
    } catch (e) {
      trackinf = await interactive(filePath, db)
    }

    if (!trackinf) {
      console.error('Nothing to do.')
      return
    }

    await db.run('INSERT INTO Track VALUES (NULL,?,?,?,?,?,?,?,?)',
      [trackinf.title, trackinf.artist, trackinf.file, trackinf.album || null, trackinf.genre || null, trackinf.track || null,
        trackinf.year || null, Math.floor(trackinf.duration)])

    console.log('Done.')
    return
  }

  let files = await getFiles(musicdir)
  let cleanTrackData = []
  let skips = 0

  for (let i in files) {
    let file = files[i]
    // if (cleanTrackData.length > 10) break // debug purposes
    process.stdout.write(`\rProcessing file ${parseInt(i) + 1} of ${files.length}.. (${skips} skipped)`)
    try {
      let fd = await getInfos(file)
      cleanTrackData.push(fd)
    } catch (e) {
      skips++
      continue
    }
  }
  process.stdout.write(`\r${cleanTrackData.length} files indexed, ${skips} files were skipped.             \n`)
  let entries = 0

  for (let i in cleanTrackData) {
    let track = cleanTrackData[i]
    process.stdout.write(`\rPopulating database.. (Track ${parseInt(i) + 1} of ${cleanTrackData.length})`)
    try {
      let ensure = await db.get('SELECT * FROM Track WHERE title=? AND artist=?', track.title, track.artist)
      if (ensure) continue
      await db.run('INSERT INTO Track VALUES (NULL,?,?,?,?,?,?,?,?)',
        [track.title, track.artist, track.file, track.album || null, track.genre || null, track.track || null,
          track.year || null, Math.floor(track.duration)])
      entries++
    } catch (e) {
      console.warn(e.message)
      continue
    }
  }

  console.log(`\n${entries} tracks were successfully added to the cache!`)
}

run()