// Copyright 2022 Clayton Craft <clayton@craftyguy.net>
// SPDX-License-Identifier: GPL-3.0-or-later

package main

import (
	"flag"
	"fmt"
	"log"
	"os"
	"path/filepath"
	"strings"
	"time"

	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/archive"
	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/bootdeploy"
	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/filelist"
	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/filelist/hookdirs"
	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/filelist/hookfiles"
	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/filelist/hookscripts"
	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/filelist/initramfs"
	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/filelist/modules"
	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/filelist/osksdl"
	"gitlab.com/postmarketOS/postmarketos-mkinitfs/internal/misc"
	"gitlab.com/postmarketOS/postmarketos-mkinitfs/pkgs/deviceinfo"
)

// set at build time
var Version string

func main() {

	outDir := flag.String("d", "/boot", "Directory to output initfs(-extra) and other boot files")
	var showVersion bool
	flag.BoolVar(&showVersion, "version", false, "Print version and quit.")
	flag.Parse()

	if showVersion {
		fmt.Printf("%s - %s\n", filepath.Base(os.Args[0]), Version)
		os.Exit(0)
	}

	deviceinfoFile := "/etc/deviceinfo"
	if !misc.Exists(deviceinfoFile) {
		log.Print("NOTE: deviceinfo (from device package) not installed yet, " +
			"not building the initramfs now (it should get built later " +
			"automatically.)")
		return
	}

	devinfo, err := deviceinfo.ReadDeviceinfo(deviceinfoFile)
	if err != nil {
		log.Fatal(err)
	}

	defer misc.TimeFunc(time.Now(), "mkinitfs")

	kernVer, err := misc.GetKernelVersion()
	if err != nil {
		log.Fatal(err)
	}

	// temporary working dir
	workDir, err := os.MkdirTemp("", "mkinitfs")
	if err != nil {
		log.Fatal("Unable to create temporary work directory:", err)
	}
	defer func() {
		e := os.RemoveAll(workDir)
		if e != nil && err == nil {
			err = e
		}
		if err != nil {
			log.Fatal(err)
		}
	}()

	log.Print("Generating for kernel version: ", kernVer)
	log.Print("Output directory: ", *outDir)

	log.Println("== Generating initramfs ==")
	if err := generateArchive("initramfs", workDir, []filelist.FileLister{
		hookdirs.New("/usr/share/mkinitfs/dirs"),
		hookdirs.New("/etc/mkinitfs/dirs"),
		hookfiles.New("/usr/share/mkinitfs/files"),
		hookfiles.New("/etc/mkinitfs/files"),
		hookscripts.New("/usr/share/mkinitfs/hooks"),
		hookscripts.New("/etc/mkinitfs/hooks"),
		modules.New(strings.Fields(devinfo.ModulesInitfs), "/usr/share/mkinitfs/modules"),
	}); err != nil {
		log.Fatalf("failed to generate %q: %s\n", "initramfs", err)
	}

	log.Println("== Generating initramfs-extra ==")
	if err := generateArchive("initramfs-extra", workDir, []filelist.FileLister{
		hookfiles.New("/usr/share/mkinitfs/files-extra"),
		hookfiles.New("/etc/mkinitfs/files-extra"),
		hookscripts.New("/usr/share/mkinitfs/hooks-extra"),
		hookscripts.New("/etc/mkinitfs/hooks-extra"),
		osksdl.New(devinfo.MesaDriver),
	}); err != nil {
		log.Fatalf("failed to generate %q: %s\n", "initramfs-extra", err)
	}

	// Final processing of initramfs / kernel is done by boot-deploy
	if err := bootDeploy(workDir, *outDir, devinfo.UbootBoardname); err != nil {
		log.Fatal("bootDeploy: ", err)
	}

}

func bootDeploy(workDir, outDir, ubootBoardname string) error {
	log.Print("== Using boot-deploy to finalize/install files ==")

	bd := bootdeploy.New(workDir, outDir, ubootBoardname)
	return bd.Run()
}

func generateArchive(name string, path string, features []filelist.FileLister) error {
	a, err := archive.New()
	if err != nil {
		return err
	}

	fs := initramfs.New(features)
	if err := a.AddItems(fs); err != nil {
		return err
	}

	log.Println("- Writing and verifying archive: ", name)
	if err := a.Write(filepath.Join(path, name), os.FileMode(0644)); err != nil {
		return err
	}

	return nil
}