'use strict';
var request = require('request');
var cheerio = require('cheerio');
var log4js = require('log4js');
var logger = log4js.getLogger();
var STRING = require('string');
var util = require('util');
var Elapsed = require('elapsed');
var clone = require('clone');
require('sugar-date');

var calendarInterface = function() {
    this.jsonBlock = [];
    this.cachedStatus = {};

    this.setJson = function(j) {
        this.jsonBlock = j;
      };
    this.getJson = function() {
        return this.jsonBlock;
      };
  };

function processICAL(ical) {
  var lines, l, counter;
  var subcounter, subBlock;
  logger.info('+ processICAL');
  var workingBlock = [];
  var segments = {
      meetingStartID: 'DTSTART;TZID=Europe/London:',
      meetingEndID: 'DTEND;TZID=Europe/London:',
      meetingDescID: 'DESCRIPTION:',
      summaryID: 'SUMMARY:',
      begin: 'BEGIN:VEVENT',
      end: 'END:VEVENT',
      beginAlarm: 'BEGIN:VALARM',
      uid: 'UID:'
    };

  function processBlock(block) {
    var alarmFlag, ws, blockStep;
    var workBlock = {
        summary: '',
        dtstart: null,
        dtend: null,
        description: '',
        timeStart: null,
        timeEnd: null,
        actualEnd: null,
        duration: 0,
        combined: '',
        uid: ''
      };
    alarmFlag = false;
    for (var step = 0; step < block.length; step++) {
      blockStep = block[step];
      if (blockStep.indexOf(segments.summaryID) >= 0) {
        workBlock.summary = STRING(block[step].split(segments.summaryID)[1]).collapseWhitespace().s;
      }
      if (blockStep.indexOf(segments.meetingStartID) >= 0) {
        ws = STRING(block[step].split(segments.meetingStartID)[1]).collapseWhitespace().s;
        workBlock.dtstart = Date.create(ws);
      }
      if (blockStep.indexOf(segments.meetingEndID) >= 0) {
        ws = STRING(block[step].split(segments.meetingEndID)[1]).collapseWhitespace().s;
        workBlock.dtend = Date.create(ws);
        workBlock.actualEnd = workBlock.dtend;
      }
      if (blockStep.indexOf(segments.meetingStartAlt) >= 0) {
        ws = STRING(block[step].split(segments.meetingStartAlt)[1]).collapseWhitespace().s;
        workBlock.dtstart = Date.create(ws);
      }
      if (blockStep.indexOf(segments.meetingEndAlt) >= 0) {
        ws = STRING(block[step].split(segments.meetingEndAlt)[1]).collapseWhitespace().s;
        workBlock.dtend = Date.create(ws);
      }
      if (blockStep.indexOf(segments.meetingDescID) >= 0 && !alarmFlag) {
        workBlock.description = STRING(block[step].split(segments.meetingDescID)[1]).collapseWhitespace().s;
      }

      if (blockStep.indexOf(segments.uid) >= 0 && !alarmFlag) {
        workBlock.uid = STRING(block[step].split(segments.uid)[1]).collapseWhitespace().s;
      }

      if (blockStep.indexOf(segments.beginAlarm) >= 0) {
        alarmFlag = true;
      }
    }

    if (workBlock.dtstart !== null) {
      workBlock.timeStart = workBlock.dtstart.format('{24hr}:{mm}:{ss} {tt}');
      workBlock.cronStart = workBlock.dtstart.format('{m} {H} * * *');
      workBlock.combined =  workBlock.timeStart + ' - ';
    }
    workBlock.combined = workBlock.combined + workBlock.summary;

    if (workBlock.dtend !== null) {
      var fiveMins;
      workBlock.timeEnd = workBlock.actualEnd.format('{24hr}:{mm}:{ss} {tt}');
      workBlock.cronStop = workBlock.actualEnd.format('{m} {H} * * *');

      fiveMins = Date.create(workBlock.actualEnd).addMinutes('-5');
      workBlock.cronAlert = fiveMins.format('{m} {H} * * *');
    }

    if (workBlock.dtstart !== null && workBlock.dtend !== null) {
      var elapsedTime = new Elapsed(workBlock.dtstart, workBlock.dtend);
      workBlock.duration = elapsedTime.optimal;
      workBlock.combined = workBlock.combined + ', ' + elapsedTime.optimal;
    }

    return workBlock;
  }

  lines = ical.split('\r\n');
  l = lines.length;
  counter = 0;

  while (counter < l) {
    if (lines[counter].indexOf(segments.begin) < 0) {
      counter++;
    } else {
      subcounter = 0;
      subBlock = [];
      while (subcounter < 75) {
        if (lines[counter + subcounter].indexOf(segments.end) < 0) {
          subBlock.push(lines[counter + subcounter]);
          subcounter++;
        } else {
          break;
        }
      }
      counter = counter + subcounter;
      workingBlock.push(processBlock(subBlock));
    }
  }
  logger.info(workingBlock.length);
  logger.info('- processICAL');
  return workingBlock;
}

calendarInterface.prototype.getTodaysMeetings = function() {
    logger.info('+ getTodaysMeetings');
    var today = {
        previous: [], upcoming: [], current: {}
      };
    var now = new Date();
    var jBlock = this.getJson();
    logger.debug(jBlock.length);
    for (var t = 0; t < jBlock.length; t++) {
      if (jBlock[t].dtstart.isToday()) {

        if (now.isBetween(jBlock[t].dtstart, jBlock[t].dtend)) {
          today.current = jBlock[t];
        }

        if (jBlock[t].dtstart.isAfter(now)) {
          today.upcoming.push(jBlock[t]);
        } else {
          if (Object.keys(today.current).length > 0) {
            if (today.current.uid !== jBlock[t].uid) {
              today.previous.push(jBlock[t]);
            }
          } else {
            today.previous.push(jBlock[t]);
          }

        }


      }
    }

    logger.info('- getTodaysMeetings');
    return today;
  };

calendarInterface.prototype.getCachedStatus = function() {
    return this.cachedStatus;
  };

calendarInterface.prototype.getRoomStatusV2 = function(cb) {
    var self = this;

    request('http://crmplace.com/censis/ical_server.php?type=ics&key=largemeetingroom&email=largemeetingroom@censis.org.uk', function(err, res, body) {
        if (err) {
          logger.error('Get remote Calendar Request failed');
          return;
        }

        self.setJson(processICAL(body));
        var processedList = self.getTodaysMeetings();
        self.cachedStatus = clone(processedList);
        if (typeof cb === 'function') {
          cb(processedList);
        }
      });
  };

module.exports.calendarInterface = calendarInterface;