app.factory("TodoService",['$log','pouchDB','$window',function($log,pouchDB,$window){
    $window.PouchDB = pouchdb;
    var db = pouchDB('todos');
    var instance = {};
    instance.get = function get(){
        var res = db.allDocs({include_docs: true, descending: true})
          .then(function(data){
                var pluck = function pluck(data,prop)
                {
                    var res = [];
                    for(var i=0;i<data.length;i++)
                    {
                        res.push(data[i][prop]);
                    }
                    return res;
                };
                var _res = pluck(data.rows,'doc');
                return _res;
          }).catch(function(err){
                $log.error("The error is \n\t",err);
                $log.error("The stacktrace is \n\t",err.stack);
          });
          return res;
    };

    instance.getOne = function getOne(id){
        var res = db.get(id)
        .then(function(data){
            return data;
        })
        .catch(function(err){
            console.log(err,err.stack);
        });
        return res;
    };

    instance.edit = function edit(todo)
        {
            var promise = db.put(todo);
            promise.then(function(response){
                $log.info("Successfully updated the todo item\t",response);
            }).catch(function(err){
                $log.error('An error occured when updating todo');
                $log.error(err,"\n",err.stack);
            });
        };

    instance.save = function save(todo){
            var isOk = function isOk(response)
            {
                if(response.ok)
                    $log.info("The document has  been saved with id ",response);

                return response;
            };

            var uhOh = function uhOh(err)
            {
                $log.error(err);
                $log.error(err.stack);
            };

            var promise = db.post(todo)
            .then(isOk)
            .catch(uhOh);
            return promise;
        };

    instance.deleteItem = function(todo){
            $log.info("Inside delete ","todo value is ",todo);
            db.remove(todo);
        };

    return instance;
}]);