var exec = require('child_process').exec,
  fs = require ('fs'),
  path = require('path'),
  exec_helper = require('./exec_helper'),
  redis = require('redis'),
  client = redis.createClient(),
  later = require('later').later;
  enParser = require('later').enParser,
  job_queue = [];

  fs.exists || (fs.exists = path.exists);

function execute_job(file) {
  exec_helper.execute_program(file, true);
  console.log("execute_job");
  console.log(file.key);

  client.hmset(file.key, "last_run", new Date(), function() {
    //repopulate the job list in the editor
  });
}

function schedule_job(key, job) {
      var is_new_job = true,
          l = later(60),
          schedule = enParser().parse(job.text);

      l.exec(schedule, new Date(), execute_job, job);
      console.log("Job Scheduled: ", schedule);

      var len = job_queue.length;
      for (var i=0; i<len; i++) {
        if (job_queue[i].key === key) {
          //job already exists, but has been modified, let's stop the existing one
          job_queue[i].later.stopExec();

          //replace it in the queue
          job_queue[i] = {key: key, later: l};

          is_new_job = false;
          break;
        }
      }

      if (is_new_job) {
        job_queue.push({key: key, later: l});
      }

      //console.log(job_queue);
}


exports.emit_scheduled_jobs = function emit_scheduled_jobs(username, socket) {
  var job_list = [];
  client.smembers("jobs", function(err, res) {
    res.forEach(function(key, i) {
      client.hgetall(key, function(err, job_data) {
        if (job_data.username === username) {
          job_list.push(job_data);
        }

        if (res.length === (i+1)) {
          socket.emit('scheduled-job-list', job_list);
        }
      });
    });
  });
};

/*
 * Create new schedule
 */
exports.add_schedule = function(schedule, socket, session) {
  var self = this;
  schedule.file.username = session.username;
  var file_path = schedule.file.path.replace('\/filesystem\/', '\/repositories\/');
  var key = "jobs:" + file_path.replace(/\W/g, '');  //keep only alphanumeric for key
  var job_data = {
      text: schedule.text,
      name: schedule.file.name,
      key: key,
      last_run: "",
      active: "1",
      path: file_path,
      extension: schedule.file.extension,
      username: schedule.file.username
  };
  console.log("add_schedule");
  console.log(job_data);

  client.sadd("jobs", key, function() {
    client.hmset(key, job_data, function() {
      schedule_job(key, job_data);
      //repopulate the job list in the editor
      self.emit_scheduled_jobs(session.username, socket);
    });
  });
};

exports.delete_job = function(key, socket, session) {
  var self = this;
  var len = job_queue.length;
  for (var i=0; i<len; i++) {
    if (job_queue[i].key === key) {
      //job exists, lets delete it
      job_queue[i].later.stopExec();
      //remove from array
      job_queue.splice(i, 1);
      //remove from redis
      client.del(key);
      client.srem("jobs", key);
      //emit change to front-end
      self.emit_scheduled_jobs(session.username, socket);
      break;
    }
  }
};

exports.toggle_job = function(key, socket, session) {
  var self = this;
  console.log(key);
  client.hgetall(key, function(err, job) {
    console.log(job);
    //toggle status
    job.active = 1-job.active;

    client.hmset(key, "active", job.active, function() {
      if (!job.active) {
        //remove job from queue, but not redis
        var len = job_queue.length;
        for (var i=0; i<len; i++) {
          if (job_queue[i].key === key) {
            //job exists, lets delete it
            job_queue[i].later.stopExec();
            //remove from array
            job_queue.splice(i, 1);
            //emit change to front-end
            self.emit_scheduled_jobs(session.username, socket);
            break;
          }
        }
      } else {
        schedule_job(key, job);
        //repopulate the job list in the editor
        self.emit_scheduled_jobs(session.username, socket);
      }


    });
  });

};

/*
 * Jobs initialized at server startup
 */
exports.initialize_jobs = function() {
  client.smembers("jobs", function(err, res) {
    res.forEach(function(key) {
      client.hgetall(key, function(err, job_data) {
        schedule_job(key, job_data);
      });
    });
  });
};