package database

import (
	"log"

	"database/sql"

	_ "github.com/mattn/go-sqlite3"
)

type Migrator func(*sql.DB) (*sql.DB, error)

func AddFriends(dbConn *sql.DB) (*sql.DB, error) {
	_, err := dbConn.Exec(`CREATE TABLE IF NOT EXISTS frens (
           id TEXT PRIMARY KEY,
           name TEXT
        );`)
	if err != nil {
		return dbConn, err
	}

	log.Println("creating unique index on frens table")
	_, err = dbConn.Exec(`CREATE UNIQUE INDEX IF NOT EXISTS idx_frens_name ON frens (name);`)
	if err != nil {
		return dbConn, err
	}

	return dbConn, nil
}

func AddMessages(dbConn *sql.DB) (*sql.DB, error) {
	_, err := dbConn.Exec(`CREATE TABLE IF NOT EXISTS messages (
           id TEXT PRIMARY KEY,
           fren_id TEXT,
           message TEXT,
           time TIMESTAMP,
           fren_sent BOOLEAN NOT NULL CHECK (fren_sent IN (0, 1)),
           FOREIGN KEY (fren_id) REFERENCES frens (id) ON DELETE CASCADE
        );`)
	if err != nil {
		return dbConn, err
	}

	log.Println("creating time and fren_id index on message table")
	_, err = dbConn.Exec(`CREATE INDEX IF NOT EXISTS idx_message_timestamp ON messages (time);`)
	_, err = dbConn.Exec(`CREATE INDEX IF NOT EXISTS idx_message_fren ON messages (fren_id);`)
	if err != nil {
		return dbConn, err
	}

	return dbConn, nil
}

func Migrate(dbConn *sql.DB) (*sql.DB, error) {
	log.Println("migrating database")

	migrations := []Migrator{
		AddFriends,
		AddMessages,
	}

	for _, migration := range migrations {
		dbConn, err := migration(dbConn)
		if err != nil {
			return dbConn, err
		}
	}

	return dbConn, nil
}