var gulp = require("gulp");
var FtpClient = require("ftp");
var minimist = require("minimist");
var readdirp = require("readdirp");
var paths = require('../paths');

var _maxConcurrentActions = 10;
var _knownOptions = {
    string: [
        "source",
        "url",
        "username",
        "password"
    ],
    default: {
        source: "./"
    }
};
var _options = minimist(process.argv.slice(2), _knownOptions);
var _client = null;
var _createdPaths = [];

gulp.task("clean-ftp", function (done) {
    var actions = [];

    openClient(function () {
        _client.list(".", false, function (err, list) {
            if (err) {
                console.log("Error reading root dir from server: " + err);
                closeClient(done);
            }
            else {
                for (var item of list) {
                    if (item.type === "d") {
                        actions.push(deleteDirAction(item.name));
                    }
                    else if (item.type === "-") {
                        actions.push(deleteFileAction(item.name));
                    }
                }

                executeActions(actions, function () {
                    closeClient(done);
                });
            }
        });
    });
});

gulp.task("deploy-ftp", ["clean-ftp"], function (done) {
    var actions = [];

    openClient(function () {
        readdirp({
            root: _options.source
        }, function (entryInfo) {
            actions.push(uploadFileAction(entryInfo));
        }, function (err, res) {
            if (err) {
                console.log("Error reading local directory: " + err);
                closeClient(done);
            }
            else {
                executeActions(actions, function () {
                    closeClient(done);
                });
            }
        });
    });
});

gulp.task("deploy", ["deploy-ftp"]);

function openClient(callback) {
    console.log("Opening FTP connection to '" + _options.url + "'...");

    _client = new FtpClient();
    _client.on("ready", callback);
    _client.on("error", console.log);
    _client.connect({
        host: _options.url,
        user: _options.username,
        password: _options.password
    });
}

function closeClient(callback) {
    if (_client) {
        _client.end();
    }

    callback();
}

function deleteDirAction(path) {
    return function (callback) {
        console.log("Deleting dir '" + path + "' from server...");
        _client.rmdir(path, true, callback);
    };
}

function deleteFileAction(path) {
    return function (callback) {
        console.log("Deleting file '" + path + "' from server...");
        _client.delete(path, callback);
    };
}

function createDirAction(path) {
    return function (callback) {
        console.log("Creating dir '" + path + "'...");
        _client.mkdir(path, false, function (err) {
            if (err) {
                console.log("Error creating dir '" + path + "': " + err);
            }

            callback();
        });
    };
}

function uploadFileAction(entryInfo) {
    return function (callback) {
        var actions = [];

        if (entryInfo.parentDir != "") {
            var dirs = entryInfo.parentDir.split("\\");
            var fullDir = "";

            dirs.forEach(function (dir) {
                if (fullDir.length > 0) {
                    fullDir += "\\";
                }

                fullDir += dir;

                if (_createdPaths.indexOf(fullDir) < 0) {
                    actions.push(createDirAction(fullDir));
                    _createdPaths.push(fullDir);
                }
            });
        }

        executeActions(actions, function () {
            console.log("Uploading '" + entryInfo.path + "'...");
            _client.put(entryInfo.fullPath, entryInfo.path, function (err) {
                if (err) {
                    console.log("Error uploading '" + entryInfo.path + "': " + err);
                }

                callback();
            });
        });
    };
}

function executeActions(actions, callback) {
    executeActionsRecursive(actions, 0, callback);
}

function executeActionsRecursive(actions, startIndex, callback) {
    var endIndex = (startIndex + _maxConcurrentActions);
    var actionsToExecute = actions.slice(startIndex, endIndex);
    var promises = [];

    if (actionsToExecute.length > 0) {
        actionsToExecute.forEach(function (action) {
            promises.push(new Promise(function (resolve) {
                action(resolve);
            }));
        });

        Promise
            .all(promises)
            .then(function () {
                executeActionsRecursive(actions, endIndex, callback);
            });
    }
    else {
        callback();
    }
}