'use strict';

// code below is highly experimental, although it runs fine on latest firmware
// the data inside nested objects needs to be verified if deep copy works properly
function configuration_backup(callback) {
    var activeProfile = null,
        profilesN = 3;

    var profileSpecificData = [
        MSP_codes.MSP_PID,
        MSP_codes.MSP_RC_TUNING,
        MSP_codes.MSP_ACC_TRIM,
        MSP_codes.MSP_SERVO_CONF
    ];

    var uniqueData = [
        MSP_codes.MSP_BOXNAMES,
        MSP_codes.MSP_BOX,
        MSP_codes.MSP_MISC,
        MSP_codes.MSP_RCMAP,
        MSP_codes.MSP_CONFIG
    ];

    var configuration = {
        'generatedBy': chrome.runtime.getManifest().version,
        'profiles': []
    };

    MSP.send_message(MSP_codes.MSP_STATUS, false, false, function () {
        activeProfile = CONFIG.profile;
        select_profile();
    });

    function select_profile() {
        if (activeProfile > 0) {
            MSP.send_message(MSP_codes.MSP_SELECT_SETTING, [0], false, fetch_specific_data);
        } else {
            fetch_specific_data();
        }
    }

    function fetch_specific_data() {
        var fetchingProfile = 0,
            codeKey = 0;

        function query() {
            if (fetchingProfile < profilesN) {
                MSP.send_message(profileSpecificData[codeKey], false, false, function () {
                    codeKey++;

                    if (codeKey < profileSpecificData.length) {
                        query();
                    } else {
                        configuration.profiles.push({
                            'PID': jQuery.extend(true, [], PIDs),
                            'RC': jQuery.extend(true, {}, RC_tuning),
                            'AccTrim': jQuery.extend(true, [], CONFIG.accelerometerTrims),
                            'ServoConfig': jQuery.extend(true, [], SERVO_CONFIG)
                        });

                        codeKey = 0;
                        fetchingProfile++;

                        MSP.send_message(MSP_codes.MSP_SELECT_SETTING, [fetchingProfile], false, query);
                    }
                });
            } else {
                MSP.send_message(MSP_codes.MSP_SELECT_SETTING, [activeProfile], false, fetch_unique_data);
            }
        }

        // start fetching
        query();
    }

    function fetch_unique_data() {
        var codeKey = 0;

        function query() {
            if (codeKey < uniqueData.length) {
                MSP.send_message(uniqueData[codeKey], false, false, function () {
                    codeKey++;
                    query();
                });
            } else {
                configuration.AUX = jQuery.extend(true, [], AUX_CONFIG_values);
                configuration.MISC = jQuery.extend(true, {}, MISC);
                configuration.RCMAP = jQuery.extend(true, [], RC_MAP);
                configuration.BF_CONFIG = jQuery.extend(true, {}, BF_CONFIG);

                save();
            }
        }

        // start fetching
        query();
    }

    function save() {
        var chosenFileEntry = null;

        var accepts = [{
            extensions: ['txt']
        }];

        // generate timestamp for the backup file
        var d = new Date(),
            now = (d.getMonth() + 1) + '.' + d.getDate() + '.' + d.getFullYear() + '.' + d.getHours() + '.' + d.getMinutes();

        // create or load the file
        chrome.fileSystem.chooseEntry({type: 'saveFile', suggestedName: 'baseflight_backup_' + now, accepts: accepts}, function (fileEntry) {
            if (chrome.runtime.lastError) {
                console.error(chrome.runtime.lastError.message);
                return;
            }

            if (!fileEntry) {
                console.log('No file selected, backup aborted.');
                return;
            }

            chosenFileEntry = fileEntry;

            // echo/console log path specified
            chrome.fileSystem.getDisplayPath(chosenFileEntry, function (path) {
                console.log('Backup file path: ' + path);
            });

            // change file entry from read only to read/write
            chrome.fileSystem.getWritableEntry(chosenFileEntry, function (fileEntryWritable) {
                // check if file is writable
                chrome.fileSystem.isWritableEntry(fileEntryWritable, function (isWritable) {
                    if (isWritable) {
                        chosenFileEntry = fileEntryWritable;

                        // crunch the config object
                        var serialized_config_object = JSON.stringify(configuration);
                        var blob = new Blob([serialized_config_object], {type: 'text/plain'}); // first parameter for Blob needs to be an array

                        chosenFileEntry.createWriter(function (writer) {
                            writer.onerror = function (e) {
                                console.error(e);
                            };

                            var truncated = false;
                            writer.onwriteend = function () {
                                if (!truncated) {
                                    // onwriteend will be fired again when truncation is finished
                                    truncated = true;
                                    writer.truncate(blob.size);

                                    return;
                                }

                                console.log('Write SUCCESSFUL');
                                if (callback) callback();
                            };

                            writer.write(blob);
                        }, function (e) {
                            console.error(e);
                        });
                    } else {
                        // Something went wrong or file is set to read only and cannot be changed
                        console.log('File appears to be read only, sorry.');
                    }
                });
            });
        });
    }
}

function configuration_restore(callback) {
    var chosenFileEntry = null;

    var accepts = [{
        extensions: ['txt']
    }];

    // load up the file
    chrome.fileSystem.chooseEntry({type: 'openFile', accepts: accepts}, function (fileEntry) {
        if (chrome.runtime.lastError) {
            console.error(chrome.runtime.lastError.message);
            return;
        }

        if (!fileEntry) {
            console.log('No file selected, restore aborted.');
            return;
        }

        chosenFileEntry = fileEntry;

        // echo/console log path specified
        chrome.fileSystem.getDisplayPath(chosenFileEntry, function (path) {
            console.log('Restore file path: ' + path);
        });

        // read contents into variable
        chosenFileEntry.file(function (file) {
            var reader = new FileReader();

            reader.onprogress = function (e) {
                if (e.total > 1048576) { // 1 MB
                    // dont allow reading files bigger then 1 MB
                    console.log('File limit (1 MB) exceeded, aborting');
                    reader.abort();
                }
            };

            reader.onloadend = function (e) {
                if (e.total != 0 && e.total == e.loaded) {
                    console.log('Read SUCCESSFUL');

                    try { // check if string provided is a valid JSON
                        var deserialized_configuration_object = JSON.parse(e.target.result);
                    } catch (e) {
                        // data provided != valid json object
                        console.log('Data provided != valid JSON string, restore aborted.');

                        return;
                    }

                    configuration_upload(deserialized_configuration_object, callback);
                }
            };

            reader.readAsText(file);
        });
    });

    function configuration_upload(configuration, callback) {
        // TODO implement this

        /*
        // check if all attributes that we will be saving exist inside the configuration object
        var validate = [
            'PID',
            'AUX_val',
            'RC',
            'AccelTrim',
            'MISC',
            'SERVO_CONFIG'
        ];

        for (var i = 0; i < validate.length; i++) {
            if (typeof (configuration[validate[i]]) === 'undefined') {
                GUI.log(chrome.i18n.getMessage('backupFileIncompatible'));
                return;
            }
        }

        // replace data
        PIDs = configuration.PID;
        AUX_CONFIG_values = configuration.AUX_val;
        RC_tuning = configuration.RC;
        CONFIG.accelerometerTrims = configuration.AccelTrim;
        MISC = configuration.MISC;
        SERVO_CONFIG = configuration.SERVO_CONFIG;

        function rc_tuning() { // Send over the RC_tuning changes
            MSP.send_message(MSP_codes.MSP_SET_RC_TUNING, MSP.crunch(MSP_codes.MSP_SET_RC_TUNING), false, aux);
        }

        function aux() { // Send over the AUX changes
            MSP.send_message(MSP_codes.MSP_SET_BOX, MSP.crunch(MSP_codes.MSP_SET_BOX), false, trim);
        }

        function trim() { // Send over the new trims
            MSP.send_message(MSP_codes.MSP_SET_ACC_TRIM, MSP.crunch(MSP_codes.MSP_SET_ACC_TRIM), false, misc);
        }

        function misc() { // Send ove the new MISC
            MSP.send_message(MSP_codes.MSP_SET_MISC, MSP.crunch(MSP_codes.MSP_SET_MISC), false, servo_conf);
        }

        function servo_conf() { // send over the new SERVO_CONF
            MSP.send_message(MSP_codes.MSP_SET_SERVO_CONF, MSP.crunch(MSP_codes.MSP_SET_SERVO_CONF), false, save_eeprom);
        }

        function save_eeprom() {
            MSP.send_message(MSP_codes.MSP_EEPROM_WRITE, false, false, function () {
                GUI.log(chrome.i18n.getMessage('eeprom_saved_ok'));
                if (callback) callback();
            });
        }

        // Send over the PID changes
        MSP.send_message(MSP_codes.MSP_SET_PID, MSP.crunch(MSP_codes.MSP_SET_PID), false, rc_tuning);
        */
    }
}