'use strict';

exports = module.exports = {
    get: get,
    getByUsername: getByUsername,
    getByEmail: getByEmail,
    getByAccessToken: getByAccessToken,
    getByResetToken: getByResetToken,
    getOwner: getOwner,
    getAllWithGroupIds: getAllWithGroupIds,
    getAllAdmins: getAllAdmins,
    add: add,
    del: del,
    update: update,
    count: count,

    _clear: clear
};

var assert = require('assert'),
    constants = require('./constants.js'),
    database = require('./database.js'),
    debug = require('debug')('box:userdb'),
    DatabaseError = require('./databaseerror'),
    mailboxdb = require('./mailboxdb.js');

var USERS_FIELDS = [ 'id', 'username', 'email', 'password', 'salt', 'createdAt', 'modifiedAt', 'resetToken', 'displayName' ].join(',');

function postProcess(result) {
    assert.strictEqual(typeof result, 'object');

    return result;
}

function get(userId, callback) {
    assert.strictEqual(typeof userId, 'string');
    assert.strictEqual(typeof callback, 'function');

    database.query('SELECT ' + USERS_FIELDS + ' FROM users WHERE id = ?', [ userId ], function (error, result) {
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));
        if (result.length === 0) return callback(new DatabaseError(DatabaseError.NOT_FOUND));

        callback(null, postProcess(result[0]));
    });
}

function getByUsername(username, callback) {
    assert.strictEqual(typeof username, 'string');
    assert.strictEqual(typeof callback, 'function');

    database.query('SELECT ' + USERS_FIELDS + ' FROM users WHERE username = ?', [ username ], function (error, result) {
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));
        if (result.length === 0) return callback(new DatabaseError(DatabaseError.NOT_FOUND));

        callback(null, postProcess(result[0]));
    });
}

function getByEmail(email, callback) {
    assert.strictEqual(typeof email, 'string');
    assert.strictEqual(typeof callback, 'function');

    database.query('SELECT ' + USERS_FIELDS + ' FROM users WHERE email = ?', [ email ], function (error, result) {
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));
        if (result.length === 0) return callback(new DatabaseError(DatabaseError.NOT_FOUND));

        callback(null, postProcess(result[0]));
    });
}

function getOwner(callback) {
    assert.strictEqual(typeof callback, 'function');

    // the first created user it the admin
    database.query('SELECT ' + USERS_FIELDS + ' FROM users, groupMembers WHERE groupMembers.groupId = ? AND users.id = groupMembers.userId ORDER BY createdAt LIMIT 1',
            [ constants.ADMIN_GROUP_ID ], function (error, result) {
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));
        if (result.length === 0) return callback(new DatabaseError(DatabaseError.NOT_FOUND));

        callback(null, postProcess(result[0]));
    });
}

function getByResetToken(resetToken, callback) {
    assert.strictEqual(typeof resetToken, 'string');
    assert.strictEqual(typeof callback, 'function');

    if (resetToken.length === 0) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, 'Empty resetToken not allowed'));

    database.query('SELECT ' + USERS_FIELDS + ' FROM users WHERE resetToken=?', [ resetToken ], function (error, result) {
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));
        if (result.length === 0) return callback(new DatabaseError(DatabaseError.NOT_FOUND));

        callback(null, postProcess(result[0]));
    });
}

function getAllWithGroupIds(callback) {
    assert.strictEqual(typeof callback, 'function');

    database.query('SELECT ' + USERS_FIELDS + ',GROUP_CONCAT(groupMembers.groupId) AS groupIds ' +
                    ' FROM users LEFT OUTER JOIN groupMembers ON users.id = groupMembers.userId ' +
                    ' GROUP BY users.id ORDER BY users.username', function (error, results) {
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));

        results.forEach(function (result) {
            result.groupIds = result.groupIds ? result.groupIds.split(',') : [ ];
        });

        results.forEach(postProcess);

        callback(null, results);
    });
}

function getAllAdmins(callback) {
    assert.strictEqual(typeof callback, 'function');

    database.query('SELECT ' + USERS_FIELDS + ' FROM users, groupMembers WHERE groupMembers.groupId = ? AND users.id = groupMembers.userId ORDER BY username', [ constants.ADMIN_GROUP_ID ], function (error, results) {
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));

        results.forEach(postProcess);

        callback(null, results);
    });
}

function add(userId, user, callback) {
    assert.strictEqual(typeof userId, 'string');
    assert(user.username === null || typeof user.username === 'string');
    assert.strictEqual(typeof user.password, 'string');
    assert.strictEqual(typeof user.email, 'string');
    assert.strictEqual(typeof user.salt, 'string');
    assert.strictEqual(typeof user.createdAt, 'string');
    assert.strictEqual(typeof user.modifiedAt, 'string');
    assert.strictEqual(typeof user.resetToken, 'string');
    assert.strictEqual(typeof user.displayName, 'string');
    assert.strictEqual(typeof callback, 'function');

    var queries = [];
    queries.push({
        query: 'INSERT INTO users (id, username, password, email, salt, createdAt, modifiedAt, resetToken, displayName) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)',
        args: [ userId, user.username, user.password, user.email, user.salt, user.createdAt, user.modifiedAt, user.resetToken, user.displayName ]
    });
    if (user.username) {
        queries.push({
            query: 'INSERT INTO mailboxes (name, ownerId, ownerType) VALUES (?, ?, ?)',
            args: [ user.username, userId, mailboxdb.TYPE_USER ]
        });
    }

    database.transaction(queries, function (error, result) {
        if (error && error.code === 'ER_DUP_ENTRY') {
            var msg = error.message;
            if (error.message.indexOf('users_email') !== -1) {
                msg = 'email already exists';
            } else if (error.message.indexOf('users_username') !== -1) {
                msg = 'username already exists';
            } else {
                msg = 'mailbox already exists';
            }

            return callback(new DatabaseError(DatabaseError.ALREADY_EXISTS, msg));
        }
        if (error || result[0].affectedRows !== 1) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));

        callback(null);
    });
}

function del(userId, callback) {
    assert.strictEqual(typeof userId, 'string');
    assert.strictEqual(typeof callback, 'function');

    // also cleanup the groupMembers table
    var queries = [];
    queries.push({ query: 'DELETE FROM groupMembers WHERE userId = ?', args: [ userId ] });
    queries.push({ query: 'DELETE FROM users WHERE id = ?', args: [ userId ] });
    queries.push({ query: 'DELETE FROM mailboxes WHERE ownerId=?', args: [ userId ] });

    database.transaction(queries, function (error, result) {
        if (error && error.code === 'ER_NO_REFERENCED_ROW_2') return callback(new DatabaseError(DatabaseError.NOT_FOUND, error));
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));
        if (result[1].affectedRows !== 1) return callback(new DatabaseError(DatabaseError.NOT_FOUND));

        callback(error);
    });
}

function getByAccessToken(accessToken, callback) {
    assert.strictEqual(typeof accessToken, 'string');
    assert.strictEqual(typeof callback, 'function');

    debug('getByAccessToken: ' +  accessToken);

    database.query('SELECT ' + USERS_FIELDS + ' FROM users, tokens WHERE tokens.accessToken = ?', [ accessToken ], function (error, result) {
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));
        if (result.length === 0) return callback(new DatabaseError(DatabaseError.NOT_FOUND));

        callback(null, postProcess(result[0]));
    });
}

function clear(callback) {
    database.query('DELETE FROM users', function (error) {
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));

        callback(error);
    });
}

function update(userId, user, callback) {
    assert.strictEqual(typeof userId, 'string');
    assert.strictEqual(typeof user, 'object');
    assert.strictEqual(typeof callback, 'function');

    var args = [ ];
    var fields = [ ];
    for (var k in user) {
        fields.push(k + ' = ?');

        if (k === 'username') {
            assert(user.username === null || typeof user.username === 'string');
            args.push(user.username);
        } else if (k === 'email') {
            assert.strictEqual(typeof user.email, 'string');
            args.push(user.email);
        } else {
            args.push(user[k]);
        }
    }
    args.push(userId);

    var queries = [];
    queries.push({ query: 'UPDATE users SET ' + fields.join(', ') + ' WHERE id = ?', args: args });
    if (user.username) {
        // delete old mailbox
        queries.push({ query: 'DELETE FROM mailboxes WHERE ownerId = ? AND aliasTarget IS NULL', args: [ userId ] });
        // add new mailbox
        queries.push({
            query: 'INSERT INTO mailboxes (name, ownerId, ownerType) VALUES (?, ?, ?)',
            args: [ user.username, userId, mailboxdb.TYPE_USER ]
        });
    }

    database.transaction(queries, function (error, result) {
        if (error && error.code === 'ER_DUP_ENTRY') {
            var msg = error.message;
            if (error.message.indexOf('users_email') !== -1) {
                msg = 'email already exists';
            } else if (error.message.indexOf('users_username') !== -1) {
                msg = 'username already exists';
            } else {
                msg = 'mailbox already exists';
            }

            return callback(new DatabaseError(DatabaseError.ALREADY_EXISTS, msg));
        }
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));
        if (result[0].affectedRows !== 1) return callback(new DatabaseError(DatabaseError.NOT_FOUND)); // mailbox?

        return callback(null);
    });
}

function count(callback) {
    assert.strictEqual(typeof callback, 'function');

    database.query('SELECT COUNT(*) AS total FROM users', function (error, result) {
        if (error) return callback(new DatabaseError(DatabaseError.INTERNAL_ERROR, error));

        return callback(null, result[0].total);
    });
}