package main

import (
	"database/sql"
	"embed"
	"fmt"
	"log"
	"net/http"
	"os"

	"git.1e99.eu/1e99/2b2t/routes"
	_ "github.com/mattn/go-sqlite3"
)

var migrations = []string{
	`CREATE TABLE player_count (
		time INTEGER PRIMARY KEY,
		playing INTEGER,
		normal_queue INTEGER,
		priority_queue INTEGER
	);
	
	CREATE TABLE worker (
		id INTEGER PRIMARY KEY,
		name TEXT,
		token TEXT
	);`,
}

//go:embed static/*
var embedFS embed.FS

func main() {
	logger := log.New(os.Stdout, "", log.Flags())
	logger.Printf(`  ___  ____ ___ _______   __  __           _            `)
	logger.Printf(` |__ \|  _ \__ \__   __| |  \/  |         | |           `)
	logger.Printf(`    ) | |_) | ) | | |    | \  / | __ _ ___| |_ ___ _ __ `)
	logger.Printf(`   / /|  _ < / /  | |    | |\/| |/ _' / __| __/ _ \ '__|`)
	logger.Printf(`  / /_| |_) / /_  | |    | |  | | (_| \__ \ ||  __/ |   `)
	logger.Printf(` |____|____/____| |_|    |_|  |_|\__,_|___/\__\___|_|   `)
	logger.Printf(`                                                        `)
	logger.Printf(`                                                        `)

	dsn, found := os.LookupEnv("MASTER_DATABASE")
	if !found {
		logger.Printf("No \"MASTER_DATABASE\", defaulting to \"./data.sqlite\"")
		dsn = "./data.sqlite"
	}

	address, found := os.LookupEnv("MASTER_ADDRESS")
	if !found {
		logger.Printf("No \"MASTER_ADDRESS\", defaulting to \":3000\"")
		address = ":3000"
	}

	// Requires tags "sqlite_math_functions"
	db, err := sql.Open("sqlite3", dsn)
	if err != nil {
		logger.Printf("Failed to open database: %s", err)
		os.Exit(1)
	}
	defer db.Close()

	err = migrateDB(db, migrations)
	if err != nil {
		logger.Printf("Failed to migrate database: %s", err)
		os.Exit(1)
	}

	mux := http.NewServeMux()
	mux.Handle("GET /api/player-count", routes.GetPlayerCounts(db, logger))
	mux.Handle("PUT /api/player-count", routes.SubmitPlayerCounts(db, logger))
	mux.Handle("GET /", routes.FileServerSubFS(embedFS, "static"))

	logger.Printf("Listening on %s", address)
	err = http.ListenAndServe(address, routes.Logger(mux, logger))
	if err != nil {
		logger.Printf("Failed to listen: %s", err)
		os.Exit(1)
	}
}

func migrateDB(db *sql.DB, migrations []string) error {
	row := db.QueryRow(`PRAGMA user_version`)

	var version int
	err := row.Scan(&version)
	if err != nil {
		return fmt.Errorf("get user_version: %w", err)
	}

	for migrationVer, sql := range migrations {
		// Add 1 due to 0-based array indexing
		if version >= (migrationVer + 1) {
			continue
		}

		_, err = db.Exec(sql)
		if err != nil {
			return fmt.Errorf("migrate to v%d: %s", migrationVer+1, err)
		}

		version = migrationVer + 1
	}

	sql := fmt.Sprintf(`PRAGMA user_version = %d;`, version)
	_, err = db.Exec(sql)
	if err != nil {
		return fmt.Errorf("set user_version: %w", err)
	}

	return nil
}