package cli

import (
	"errors"
	"flag"
	"fmt"
	"io/ioutil"
	"net/http"
	"os"
	"path"
	"path/filepath"
	"sort"
	"strconv"
	"strings"
	"time"

	"code.fmartingr.dev/fmartingr/go-mangadex"
	"github.com/sirupsen/logrus"
)

type CliOPtions struct {
	MangaID string
}

const defaultLogLevel string = "INFO"

func fileExists(filename string) bool {
	info, err := os.Stat(filename)
	if os.IsNotExist(err) {
		return false
	}
	return !info.IsDir()
}

func DownloadFile(url string, destinationPath string) error {
	response, err := http.Get(url)
	if err != nil {
		logrus.Errorf("Error downloading page: %s", err)
		return err
	}

	if response.StatusCode != 200 {
		logrus.Errorf("Status code not OK: %d", response.StatusCode)
		return errors.New("Status code not 200")
	}

	if response.Body != nil {
		defer response.Body.Close()
	}

	file, errOpen := os.Create(destinationPath)
	if err != nil {
		logrus.Errorf("Error opening file: %s", errOpen)
		return errOpen
	}

	defer file.Close()

	body, errBody := ioutil.ReadAll(response.Body)
	if errBody != nil {
		logrus.Errorf("Failing read body from response: %s", errBody)
		return err
	}

	file.Write(body)

	return nil
}

func Start() {
	logLevelFlag := flag.String("log-level", defaultLogLevel, "Log level")
	mangaIDFlag := flag.Int("manga-id", 0, "Manga ID to convert")
	noCacheFlag := flag.Bool("no-cache", false, "Cache requests to mangadex")
	outputPath := "Output"
	flag.Parse()

	cwd, errCwd := os.Getwd()
	if errCwd != nil {
		logrus.Fatalf("Error retrieving current working directory: %s", errCwd)
	}
	outputPath = filepath.Join(cwd, outputPath)

	if !*noCacheFlag {
		mangadex.EnableCache()
	}

	logLevel, errLogLevel := logrus.ParseLevel(*logLevelFlag)
	if errLogLevel != nil {
		logrus.Warnf("Incorrect loglevel %s, using default %s", *logLevelFlag, defaultLogLevel)
	} else {
		logrus.SetLevel(logLevel)
	}

	if *mangaIDFlag == 0 {
		logrus.Error("You should set -manga-id")
		logrus.Exit(1)
	}

	logrus.Infof("Getting information for Manga ID: %d", *mangaIDFlag)
	manga, err := mangadex.GetManga(*mangaIDFlag)
	if err != nil {
		panic(err)
	}

	logrus.Infof("Found! %s", manga.Title)
	logrus.Infof("Getting chapter information...")

	var mangaChapters []mangadex.MangaChapterList
	mangaGroups := map[int]mangadex.MangaGroup{}
	chapterParams := mangadex.NewGetChaptersParams()
	currentPage := 1

	// TODO: Select language
	selectedLanguage := "gb"

	for currentPage != chapterParams.Page {
		chapterParams.Page = currentPage
		logrus.Infof("Downloading chapters page %d", currentPage)
		chapters, groups, errChapters := manga.GetChapters(chapterParams)
		if errChapters != nil {
			logrus.Errorf("Error retrieving manga chapters: %s", errChapters)
		}
		for chapter := range chapters {
			if chapters[chapter].Language == selectedLanguage {
				mangaChapters = append(mangaChapters, chapters[chapter])
			}
		}

		for group := range groups {
			_, exists := mangaGroups[groups[group].ID]
			if !exists {
				mangaGroups[groups[group].ID] = groups[group]
			}
		}

		// If we have the total number of items we try the next page
		if len(chapters) == chapterParams.Limit {
			currentPage++
		}
	}

	logrus.Printf("Found following groups: ")
	for group := range mangaGroups {
		logrus.Printf(" %6d: %s", mangaGroups[group].ID, mangaGroups[group].Name)
	}

	// TODO: Select groups for digitalization
	// TODO: Using all for testing
	selectedGroups := make([]int, 0, len(mangaGroups))
	for k := range mangaGroups {
		selectedGroups = append(selectedGroups, k)
	}

	logrus.Infof("Selected groups: %d", selectedGroups)

	logrus.Infof("Calculating Volumes...")

	mangaVolumeChapter := map[string]mangadex.MangaChapterList{}
	var mangaVolumeChapterKeys []string
	//testTest := map[string]map[string]mangadex.MangaChapter{}

	for chapter := range mangaChapters {
		if !strings.Contains(mangaChapters[chapter].Chapter, ".") {
			mangaChapters[chapter].Chapter += ".0"
		}
		volumeChapterKey := fmt.Sprintf("%04s_%08s", mangaChapters[chapter].Volume, mangaChapters[chapter].Chapter)
		_, exists := mangaVolumeChapter[volumeChapterKey]
		if !exists {
			//testTest[fmt.Sprintf("%04s", mangaChapters[chapter].Volume)][fmt.Sprintf("%08s", mangaChapters[chapter].Chapter)] = mangaChapters[chapter]
			logrus.Debugf("Collecting volume %4s chapter %4s from group %7d", mangaChapters[chapter].Volume, mangaChapters[chapter].Chapter, mangaChapters[chapter].Groups)
			mangaVolumeChapter[volumeChapterKey] = mangaChapters[chapter]
			mangaVolumeChapterKeys = append(mangaVolumeChapterKeys, volumeChapterKey)
		}
	}

	logrus.Debugf("Sorting by volume and chapter")
	sort.Strings(mangaVolumeChapterKeys)

	mangaOutputPath := filepath.Join(outputPath, manga.Title)
	for i := range mangaVolumeChapterKeys {
		chapter := mangaVolumeChapter[mangaVolumeChapterKeys[i]]
		if chapter.Volume == "1" {
			volumeOutputPath := filepath.Join(mangaOutputPath, fmt.Sprintf("%s - Volume %s", manga.Title, chapter.Volume))

			logrus.Infof("Processing Volume %s Chapter %s", chapter.Volume, chapter.Chapter)
			logrus.Tracef("Processing %s", mangaVolumeChapterKeys[i])

			errMkdir := os.MkdirAll(volumeOutputPath, 0766)
			if errMkdir != nil {
				logrus.Fatalf("Error creating output directory: %s", errMkdir)
			}

			chapterDetail, errChapterDetail := manga.GetChapter(strconv.Itoa(chapter.ID))
			if errChapterDetail != nil {
				logrus.Errorf("Failed getting chapter detail: %s", errChapterDetail)
			}

			for page := range chapterDetail.Pages {
				logrus.Infof("Processing page %s", chapterDetail.Pages[page])
				extension := path.Ext(chapterDetail.Pages[page])
				pageDestinationPath := filepath.Join(volumeOutputPath, fmt.Sprintf("%s_%03d%s", mangaVolumeChapterKeys[i], page, extension))
				if !fileExists(pageDestinationPath) {
					logrus.Tracef("Downloading page from %s", chapterDetail.Server+path.Join(chapterDetail.Hash, chapterDetail.Pages[page]))
					logrus.Tracef("Downlading page to %s", pageDestinationPath)
					errDownload := DownloadFile(chapterDetail.Server+path.Join(chapterDetail.Hash, chapterDetail.Pages[page]), pageDestinationPath)
					if errDownload != nil {
						logrus.Errorf("Error downloading page: %s", errDownload)
					}
				}
				time.Sleep(100 * time.Millisecond)
			}

		}
	}

	covers, errCovers := manga.GetCovers()
	if errCovers != nil {
		logrus.Errorf("Error getting cover information: %s", errCovers)
	}

	for cover := range covers {
		if covers[cover].Volume == "1" {
			extension := path.Ext(covers[cover].URL)
			coverOutputPath := filepath.Join(mangaOutputPath, fmt.Sprintf("%s - Volume %s", manga.Title, covers[cover].Volume), fmt.Sprintf("0000%s", extension))
			if !fileExists(coverOutputPath) {
				logrus.Tracef("Downloading cover from %s", covers[cover].URL)
				logrus.Tracef("Writting cover to: %s", coverOutputPath)
				errDownload := DownloadFile(covers[cover].URL, coverOutputPath)
				if errDownload != nil {
					logrus.Errorf("Error downloading cover: %s", errDownload)
				}
			}
			time.Sleep(100 * time.Millisecond)
		}
	}
	// TODO: Zip folders into CBR files
}