package org.opendc.common.utils

import java.sql.Connection
import java.sql.DriverManager
import java.sql.SQLException

/**
 * Represents the Postgresql database.
 * On setup cleans the entire database and creates empty tables.
 *
 * @author Mateusz
 *
 * @param address ipv4 address
 * @param port postgres post
 * @param dbName database name
 * @param user
 * @param password
 */
public class PostgresqlDB(
    address : String,
    port : Int,
    dbName : String,
    private var user : String,
    private var password : String,
) {
    private var connection : Connection? = null
    private var dbUrl : String = ""

    init {
        dbUrl = "jdbc:postgresql://$address:$port/$dbName"
        println(dbUrl)
        try {
            connection = DriverManager.getConnection(dbUrl, user, password)
            clear()
            setup()
        } catch (e: SQLException) {
            print("${e.message}")
        }
    }
    public fun setup(){
        val CREATE_TABLE = """
            CREATE TABLE metrics (
            id SERIAL PRIMARY KEY,
            timestamp bigint,
            tasksActive integer, 
            clusterName varchar(10)); 
        """.trimIndent()

        try {
            val conn = DriverManager.getConnection(dbUrl, user, password)
            val st = conn.createStatement()
            st.executeQuery(CREATE_TABLE)
        } catch (e: SQLException){
            println("${e.message}")
        }
    }

    public fun clear(){
        val DELETE_ALL_TABLES = """
            DROP SCHEMA public CASCADE;
            CREATE SCHEMA public;
        """.trimIndent()
        try {
            val conn = DriverManager.getConnection(dbUrl, user, password)
            val st = conn.createStatement()
            st.executeQuery(DELETE_ALL_TABLES)
        } catch (e: SQLException){
            println("${e.message}")
        }
    }
}