package net.exploit.statsapi.mysql;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.HashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.function.Consumer;

import org.bukkit.Bukkit;
import org.bukkit.plugin.Plugin;

import net.exploit.statsapi.main.StatsAPI;
import net.exploit.statsapi.manager.LoginInfoManager;

public class MySQL {

    private Connection connection;

    private ExecutorService executor;
    private Plugin plugin;

    private String database, hostname, username, password;
    private int port;

    public MySQL(Plugin owner) {
        executor = Executors.newCachedThreadPool();
        plugin = owner;

        loadLoginInfo();
        connect();
    }

    private void loadLoginInfo() {
        LoginInfoManager loginInfo = StatsAPI.getApi().loginInfo;
        this.database = loginInfo.getDatabase();
        this.hostname = loginInfo.getHostname();
        this.username = loginInfo.getUsername();
        this.password = loginInfo.getPassword();
        this.port = loginInfo.getPort();
    }

    private void connect() {
        try {
            Class.forName("com.mysql.jdbc.Driver");
            connection = DriverManager.getConnection("jdbc:mysql://" + this.hostname + ":" + this.port + "/" + this.database, this.username, this.password);
        } catch (SQLException | ClassNotFoundException e) {
            e.printStackTrace();
        }
    }

    public void disconnect() {
        try {
            if (isConnected())
                connection.close();
            connection = null;
        } catch (SQLException e) {
            e.printStackTrace();
        }
        this.executor.shutdown();
    }

    public boolean isConnected() {
        try {
            boolean b = this.connection != null && !this.connection.isClosed();
            return b;
        } catch (SQLException e) {
            return false;
        }
    }

    public void update(String query) {
        // System.out.println(query);
        if (isConnected())
            executor.execute(() -> {
                try {
                    Statement statement = connection.createStatement();
                    statement.executeUpdate(query);
                    statement.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            });
        else
            Bukkit.getLogger().warning("Could not execute update: '" + query + "'");
    }

    public void updateSynchronously(String query) {
        // System.out.println(query);
        if (isConnected())
            try {
                Statement statement = connection.createStatement();
                statement.executeUpdate(query);
                statement.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        else
            Bukkit.getLogger().warning("Could not execute update: '" + query + "'");
    }

    public void query(String query, Consumer<ResultSet> consumer) {
        if (isConnected())
            executor.execute(() -> {
                try {
                    Statement st = connection.createStatement();
                    ResultSet rs = st.executeQuery(query);
                    Bukkit.getScheduler().runTask(plugin, () -> consumer.accept(rs));
                } catch (SQLException ex) {
                    ex.printStackTrace();
                }
            });
        else
            Bukkit.getLogger().warning("Could not execute query: '" + query + "'");
    }

    public ResultSet query(String query) throws SQLException {
        if (isConnected()) {
            Statement st = connection.createStatement();
            return st.executeQuery(query);
        } else {
            Bukkit.getLogger().warning("Could not execute query: '" + query + "'");
            return null;
        }
    }

    public HashMap<String, String> getTableColumns(String table) {
        if (isConnected())
            try {
                ResultSet resultSet = connection.getMetaData().getColumns(this.database, null, table, "%");
                HashMap<String, String> cols = new HashMap<>();
                while (resultSet.next()) {
                    cols.put(resultSet.getString(4), resultSet.getString(6));
                }
                return cols;
            } catch (SQLException e) {
                e.printStackTrace();
                return null;
            }
        else {
            Bukkit.getLogger().warning("Could not get columns of table '" + table + "'");
            return null;
        }
    }

    public boolean tableExist(String tableName) {
        if (isConnected()) {
            boolean tExists = false;
            try (ResultSet rs = connection.getMetaData().getTables(null, null, tableName, null)) {
                while (rs.next()) {
                    String tName = rs.getString("TABLE_NAME");
                    if (tName != null && tName.equals(tableName)) {
                        tExists = true;
                        break;
                    }
                }
            } catch (SQLException e) {
                e.printStackTrace();
            }
            return tExists;
        } else {
            Bukkit.getLogger().warning("Could not check if table '" + tableName + "' exists. Assuming it does.");
            return true;
        }
    }

}