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document.getElementById('upload-photo').addEventListener('change', function(e) {
    new UploadPhoto({
        el: e.target,
        files: e.target.files,
        clubID: 3
    }).send();
});

;(function() {
    this.UploadPhoto = function(param) {
        this.param = param || {};
        this.filesCount = 40;
        this.messages = {
            error: 'Max upload photos is ' + this.filesCount,
            success: 'Photos is uploaded',
            notUploaded: 'is not uploaded',
            notValid: 'is not valid format'
        };
    }

    /**
     *
     * private methods
     *
     */

    function readFile(file) {
        var self = this;
        var reader = new FileReader();

        return new Promise(function(resolve, reject) {
            if(/^image/.test(file.type)) {
                reader.onload = function() {
                    if(reader.readyState === 2) {
                        resolve({
                            name: file.name,
                            data: reader.result
                        });
                    }
                    else {
                        reject(file.name + ' ' + self.messages.notUploaded)
                    }                         
                }
                reader.readAsDataURL(file);                    
            }
            else{
                reject(file.name + ' ' + self.messages.notValid)
            }
             
        });
      
    }
    
    /**
     *
     * public methods
     *
     */
    
    UploadPhoto.prototype = {
        getMessage: function(type) {
            return {
                type: type,
                message: this.messages[type]
            };
        },
        checkFilesCount: function() {
            return this.param.files.length > this.filesCount ? this.getMessage('error') : this.getMessage('success');
        },
        send: function() {
            var self = this;
            var check = this.checkFilesCount();
            var loaded = 0;
            var imgContainer = document.querySelector('.photos');

            if(check.type !== 'error') {
                var promises = [];

                // push promuses to array
                for (var i = this.param.files.length - 1; i >= 0; i--) {
                    promises.push(readFile.call(this, this.param.files[i]));
                }

                // array of values from all promises and send files to server
                Promise.all(promises)
                    .then(function(data) {
                        var ajax = new Ajax({
                            method: 'post',
                            url: '/admin/player.php?upload=1&gh_id=' + self.param.clubID,
                            type: 'json',
                            data: data
                        }).send();
                    })
                    .catch(function(error) {
                        toastr.error(error);
                    });                   
            }
            else {
                toastr.error(check.message);
            }
        }
    };
})();