// Command midipak creates a compressed pack from
// input MIDI files.
//
//     midipak OUTPUT INPUTS...
package main

import (
	"context"
	"database/sql"
	"fmt"
	"io/ioutil"
	"log"
	"os"
	"path"

	"github.com/klauspost/compress/zstd"
	_ "github.com/mattn/go-sqlite3"
	"go.terinstock.com/midifi/pkg/midipak"
)

func pack(ctx context.Context, output string, files []string) error {
	fa := make([]midipak.File, 0, len(files))
	for _, file := range files {
		name := path.Base(file)
		p, err := ioutil.ReadFile(file)
		if err != nil {
			return err
		}

		fa = append(fa, midipak.File{Name: name, Data: p})
	}

	enc, err := zstd.NewWriter(nil, zstd.WithEncoderLevel(zstd.SpeedBestCompression))
	if err != nil {
		return err
	}
	defer enc.Close()

	db, err := sql.Open("sqlite3", fmt.Sprintf("%s", output))
	if err != nil {
		return err
	}
	defer db.Close()

	if err := midipak.Create(ctx, db); err != nil {
		return err
	}

	if err := midipak.Pack(ctx, db, enc, fa); err != nil {
		return err
	}

	if _, err = db.Exec("VACUUM"); err != nil {
		return err
	}

	return nil
}

func main() {
	ctx := context.Background()
	output := os.Args[1]
	files := os.Args[2:]

	if err := pack(ctx, output, files); err != nil {
		log.Print(err)
	}
}