package oplcli

import (
	"fmt"
	"io"
	"log/slog"
	"net/http"
	"os"
	"path"
)

type FileMode int

const (
	ModeOverride FileMode = iota
	ModeAppend
	ModeOnlyCreate
)

func downloadCfgForGame(gameID string, output string, mode FileMode) error {
	url := getDownloadURLFromGithub(gameID)

	filePath := path.Join(output, fmt.Sprintf("%s.cfg", gameID))

	file, err := openFileBasedOnMode(filePath, mode)
	if err != nil {
		slog.Error("Failed to open cfg file", "file", filePath, "gameID", gameID, "err", err)
		return err
	}
	defer file.Close()

	resp, err := http.Get(url)
	if err != nil {
		slog.Error("Failed to download cfg file", "file", filePath, "gameID", gameID, "err", err)
		return err
	}
	defer resp.Body.Close()

	_, err = io.Copy(file, resp.Body)
	if err != nil {
		slog.Error("Failed to write cfg file", "file", filePath, "gameID", gameID, "err", err)
		return err
	}

	return nil
}

func openFileBasedOnMode(filePath string, mode FileMode) (*os.File, error) {
	_, err := os.Stat(filePath)
	if err != nil {
		if err != os.ErrNotExist {
			file, err := os.Create(filePath)
			if err != nil {
				return nil, err
			}
			return file, nil
		}
	}

	if mode == ModeOverride {
		file, err := os.OpenFile(filePath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0666)
		if err != nil {
			return nil, err
		}
		return file, nil
	}

	if mode == ModeAppend {
		file, err := os.OpenFile(filePath, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0666)
		if err != nil {
			return nil, err
		}
		return file, nil
	}

	return nil, fmt.Errorf("File already exists")

}

func getDownloadURLFromGithub(gameID string) string {
	// const baseURL = "https://raw.githubusercontent.com/VTSTech/PS2-OPL-CFG/refs/heads/master/CFG/" // This one is more basic
	const baseURL = "https://raw.githubusercontent.com/Tom-Bruise/PS2-OPL-CFG-Database/refs/heads/master/CFG_en/" // This one contains descriptions and more

	return fmt.Sprintf("%s/%s.cfg", baseURL, gameID)
}