/**
 * Created by lzy on 2017/8/1.
 *
 * 建立資料庫、使用者、以及集合指令碼
*
 * version info:
 * npm 3.10.10
 * node v6.11.1
 * mongodb v3.4.6
 */
var dbConfig = require('../config/sys-config').DB;
var userAdmin = require('../config/sys-config').UA;
var dbAdmin = require('../config/sys-config').DA;
var mongoClient = require('mongodb'
 
).MongoClient;
var mongoUri = "mongodb://" + dbAdmin.username + ':' + dbAdmin.password + '@' + dbConfig.ip + ':' + dbConfig.port + '/admin';
mongoClient.connect(
    mongoUri,
connectDbCallback
);
/*連線後回撥*/
function connectDbCallback(err, db){
    if (err){
        console.log('Connection Failed!');
}else 
 
{
        console.log('Connection Success!');
try{
            connectSuccessCallback(db);
}catch (e){
            console.log('Oper Database Error:' + e);
db.close();
return;
}
    }
}

/*連線成功呼叫*/
function connectSuccessCallback(db){
    /*刪除資料庫*/
dropDb(db);
}

/*新增使用者*/
function addUser(db){
    var admin = db.admin
 
();
var bloggerDB = db.db(dbConfig.database);
admin.authenticate(userAdmin.username, userAdmin.password, function(err, results){
        if (err){
            console.log('Authenticate userAdmin Failed! result:' + err);
}else {
            console.log('Authenticate userAdmin Success!');
bloggerDB.removeUser(dbConfig.username, function(err, results){
                if (err){
                    console.log('Delete user Failed! result:' + err);
}else{
                    console.log('Delete user Success!');
}
                bloggerDB.addUser(dbConfig.username, dbConfig.password, function(err, results){
                    if (err){
                        console.log('Add user Failed! result:' + err);
closeDB(db);
return;
}else {
                        console.log('Add user Success!');
bloggerDB.authenticate(dbConfig.username, dbConfig.password, function(err, results){
                            if (err){
                                console.log('Auth user Failed! result:' + err);
closeDB(db);
return;
}else {
                                console.log('Auth user Success!');
closeDB(db);
}
                        })
                    }
                })
            });
}
    })
}

/*是否建立成功*/
function isCreateSuccess(db){
    var admin = db.admin();
admin.listDatabases(function(err, results){
        if (err){
            console.log('show dbs error');
closeDB(db);
return;
}
        var found = false;
try{
            console.log('Current Databases:' + results.databases);
results.databases.forEach(function(element, index) {
                if (element.name == dbConfig.database){
                    found = true;
}
            })
        }catch (e) {
            console.log('show dbs error: errMsg:' + e);
closeDB(db);
return;
}

        if (found){
            console.log('Create Database ' + dbConfig.database + ' Success!');
addUser(db);
}else {
            console.log('Create Database ' + dbConfig.database + ' Failed!');
closeDB(db);
return;
}
    })
}

/*刪除DB*/
function dropDb(db){
    db.db(dbConfig.database).dropDatabase(function(err, results){
        if (!err){
            console.log('Drop ' + dbConfig.database + ' Database Success');
/*顯示刪除後的資料庫列表*/
showDbs(db);
}else {
            console.log('Drop ' + dbConfig.database + ' Database Failed; result: ' + err);
closeDB(db);
}
    })
}

/*顯示資料庫列表*/
function showDbs(db){
    var admin = db.admin();
admin.listDatabases(function(err, results){
        if (err){
            console.log("Show dbs error");
closeDB(db);
return;
}
        console.log("Current Database List: ");
console.log(results.databases);
createDbAndCol(db);
})
}


/*建立資料庫和集合*/
function createDbAndCol(db){
    var bloggerDB = db.db(dbConfig.database);
bloggerDB.createCollection('example', function(err, col){
        if (err){
            console.log('Create Database ' + dbConfig.database + ' and example ' + ' Col Failed!' + err);
closeDB(db);
return;
}
        console.log('Create Database ' + dbConfig.database + ' and example ' + ' Col Success!');
isCreateSuccess(db);
})
}

/*關閉DB*/
function closeDB(db){
    db.close(true, function(err, results){
        if (!err){
            console.log('Close DB Success!');
}else {
            console.log('Close DB Failed! Msg:' + err);
}
    });
}