package database

import (
	"database/sql"
	"errors"
	"log"

	"gopkg.in/guregu/null.v4"
)

type Server struct {
	ID       int         `json:"id"`
	Hostname null.String `json:"hostname"`
	OsId     null.String `json:"OsId"`
}

func GetServersList(db *sql.DB) ([]Server, error) {
	var servers []Server
	rows, err := db.Query("SELECT * FROM dashboard_server")
	if err != nil {
		log.Println("Error querying servers list", err)
	}
	defer func(rows *sql.Rows) {
		err := rows.Close()
		if err != nil {
			log.Println("Error closing rows query", err)
		}
	}(rows)

	for rows.Next() {
		var s Server
		err := rows.Scan(&s.ID, &s.Hostname, &s.OsId)
		if err != nil {
			log.Println("Error building servers list", err)
		}
		servers = append(servers, s)
	}
	return servers, err
}

func GetServersbyID(db *sql.DB, id int64) (Server, error) {
	var s Server
	rows := db.QueryRow("SELECT * FROM dashboard_server WHERE id = ?", id)
	err := rows.Scan(&s.ID, &s.Hostname, &s.OsId)
	if err != nil {
		return Server{}, nil
	}
	return s, err
}

func GetServersbyOS(db *sql.DB, id int64) ([]Server, error) {
	var servers []Server
	rows, err := db.Query("SELECT * FROM dashboard_server WHERE os_id = ?", id)
	if err != nil {
		log.Println("Error querying servers list by os_id", err)
		return nil, err
	}
	defer func(rows *sql.Rows) {
		err := rows.Close()
		if err != nil {
			log.Println("Error closing rows query", err)
		}
	}(rows)

	for rows.Next() {
		var s Server
		err := rows.Scan(&s.ID, &s.Hostname, &s.OsId)
		if err != nil {
			log.Println("Error building servers list", err)
		}
		servers = append(servers, s)
	}
	return servers, err
}

func checkIfServerExists(server Server, db *sql.DB) bool {
	row := db.QueryRow("SELECT hostname, os_id FROM dashboard_server WHERE hostname = ? AND os_id = ?", server.Hostname, server.OsId)
	err := row.Scan(&server.Hostname, &server.OsId)
	return !errors.Is(err, sql.ErrNoRows)
}

func CreateServer(server Server, db *sql.DB) error {
	if !checkIfServerExists(server, db) {
		log.Println("Server already exists")
		return nil
	}
	q, err := db.Prepare("INSERT INTO dashboard_server (hostname, os_id) VALUES ( ?, ?)")
	if err != nil {
		log.Println("Error creating query", err)
		return err
	}
	_, err = q.Exec(server.Hostname, server.OsId)
	if err != nil {
		log.Println("Error inserting Server", err)
		return err
	}
	return nil
}

func DeleteServer(server Server, db *sql.DB) (int, error) {
	if !checkIfServerExists(server, db) {
		log.Println("Server does not exist, nothing to delete")
		return 404, nil
	}
	q, err := db.Prepare("DELETE FROM dashboard_server WHERE hostname = ? AND os_id = ?")
	if err != nil {
		log.Println("Error deleting Server", err)
		return 500, err
	}
	_, err = q.Exec(server.Hostname, server.OsId)
	if err != nil {
		log.Println("Error deleting Server", err)
		return 500, err
	}
	log.Println("Server deleted")
	return 200, nil
}