/* Shows you which videos are available at which libraries.

   Input: A json filename, which should be a hash of the form:
   {"branches": {"Branch name": "Additional branch details (ex: hours)", ...},
   "videos": [{"Title": "URL to library page"}, ...]}.

   Example: {
   "branches": {
   "Runnymede": "M 9-8:30 T 9-8:30 W 9-8:30 Th 9-8:30 F 9-5 Sat 9-5"
   },
   "videos": [
   {"title": "Avengers: Age of Ultron", "url": "http://www.torontopubliclibrary.ca/detail.jsp?Entt=RDM3350205&R=3350205"}
   ]}

   Output:
   Status,Branch,Title,Branch notes
*/

var rp = require('request-promise');
var moment = require('moment');
var async = require('async');
var cheerio = require('cheerio');
var q = require('q');
var csv = require('fast-csv');
var fs = require('fs');

if (process.argv.length < 3) {
  console.log('Please specify the JSON file to read the branches and videos from.');
  process.exit(1);
}

var config = JSON.parse(fs.readFileSync(process.argv[2]));
var branches = config.branches;
var videos = config.videos;

/*
  Returns a promise that will resolve with an array of [status,
  branch, movie, info], where status is either the next due date, "In
  Library", etc. */
function checkStatus(branches, movie) {
  var url = movie.url;
  var matches = url.match(/R=([0-9]+)/);
  return rp.get(
    'http://www.torontopubliclibrary.ca/components/elem_bib-branch-holdings.jspf?print=&numberCopies=1&itemId='
      + matches[1]).then(function(a) {
        var $ = cheerio.load(a);
        var results = [];
        var lastBranch = '';              
        $('tr.notranslate').each(function() {
          var row = $(this);
          var cells = row.find('td');
          var branch = $(cells[0]).text().replace(/^[ \t\r\n]+|[ \t\r\n]+$/g, '');
          var due = $(cells[2]).text().replace(/^[ \t\r\n]+|[ \t\r\n]+$/g, '');
          var status = $(cells[3]).text().replace(/^[ \t\r\n]+|[ \t\r\n]+$/g, '');
          if (branch) { lastBranch = branch; }
          else { branch = lastBranch; }
          if (branches[branch]) {
            if (status == 'On loan' && (matches = due.match(/Due: (.*)/))) {
              status = moment(matches[1], 'DD/MM/YYYY').format('YYYY-MM-DD');
            }
            if (status != 'Not Available - Search in Progress') {
              results.push([status, branch, movie.title, branches[branch]]);
            }
          }
        });
        return results;
      });
}

function checkAllVideos(branches, videos) {
  var results = [];
  var p = q.defer();
  async.eachLimit(videos, 5, function(video, callback) {
    checkStatus(branches, video).then(function(result) {
      results = results.concat(result);
      callback();
    });
  }, function(err) {
    p.resolve(results.sort(function(a, b) {
      if (a[0] == 'In Library') {
        if (b[0] == 'In Library') {
          if (a[1] < b[1]) return -1;
          if (a[1] > b[1]) return 1;
          if (a[2] < b[2]) return -1;
          if (a[2] > b[2]) return 1;
          return 0;
        } else {
          return -1;
        }
      }
      if (b[0] == 'In Library') { return 1; }
      if (a[0] < b[0]) { return -1; }
      if (a[0] > b[0]) { return 1; }
      return 0;
    }));
  });
  return p.promise;
}

checkAllVideos(branches, videos).then(function(result) {
  csv.writeToString(result, {}, function(err, data) {
    console.log(data);
  });
});