package main

import (
	"errors"
	"fmt"
	"io"
	"os"
	"path/filepath"
	"time"

	"git.milar.in/milarin/adverr"
	"git.milar.in/nyaanime/logic"
	"git.milar.in/nyaanime/model"
	"git.milar.in/nyaanime/parsers"
	"github.com/fatih/color"
)

func HandleFile(fh *FileHandle) {
	defer fh.Close()
	path := fh.File
	w := fh.Writer

	fmt.Fprint(w, color.MagentaString("%s file found: %s\n", time.Now().Format("2006-01-02 15:04:05"), path))

	fmt.Fprint(w, "\ttry parsers: ")
	for i, parser := range parsers.Parsers {
		parsedFile, ok := parser.FileParser(&parser, path)
		if !ok {
			fmt.Fprint(w, color.YellowString(parser.Identity))
			if i < len(parsers.Parsers)-1 {
				fmt.Fprint(w, ", ")
			} else {
				fmt.Fprintln(w, color.RedString("\n\tfile ignored"))
			}
			continue
		}

		anime, err := logic.SearchAnimeByTitle(parsedFile.OriginalAnimeTitle)
		if err != nil {
			fmt.Fprintln(w, color.RedString(parser.Identity))
			fmt.Fprintln(w, color.RedString("\tanime not found: '%s'", parsedFile.OriginalAnimeTitle))
			break
		}

		fmt.Fprintln(w, color.GreenString(parser.Identity))

		parsedFile.Anime = anime
		HandleParsedFile(w, parsedFile)
		break
	}
}

func HandleParsedFile(w io.Writer, parsedFile *model.ParsedFile) {
	newFilePrio := logic.NewFilePriority(parsedFile)
	oldFilePrio, animeEpNotExistLocally := logic.GetAnimeEpProps(parsedFile.AnimeEpisode())

	// debug output
	if animeEpNotExistLocally {
		fmt.Fprintln(w, "\tfile exists locally")
		fmt.Fprintf(w, "\t    local file: %s\n", FilePrio2Str(oldFilePrio))
		fmt.Fprintf(w, "\t    new file:   %s\n", FilePrio2Str(newFilePrio))
		if newFilePrio.Priority > oldFilePrio.Priority {
			fmt.Fprint(w, color.GreenString("\t    overwrite local file\n"))
		} else if !DeleteLowPriorityFiles {
			fmt.Fprint(w, color.YellowString("\t    ignore new file\n"))
		}
	}

	// delete files with lower priority from DownloadPath
	if DeleteLowPriorityFiles && animeEpNotExistLocally && oldFilePrio.Priority >= newFilePrio.Priority {
		fmt.Fprint(w, color.YellowString("\tdelete file with lower priority '%s'", parsedFile.File))
		err := os.Remove(parsedFile.File)
		if err != nil {
			fmt.Fprint(w, color.RedString(" failed: '%s'\n", err.Error()))
		} else {
			fmt.Fprint(w, color.GreenString(" done\n"))
		}
		return
	}

	if !animeEpNotExistLocally || newFilePrio.Priority > oldFilePrio.Priority {
		DeleteOldAnimeEpisode(parsedFile.AnimeEpisode())
		if err := OrganizeAnimeEpisode(w, parsedFile); err != nil {
			fmt.Fprint(w, color.RedString("\terror: %s\n", err.Error()))
		}
	}
}

func OrganizeAnimeEpisode(w io.Writer, parsedFile *model.ParsedFile) error {
	PrepareTelegramAnimeEpMessage(parsedFile.AnimeEpisode())

	start := time.Now()

	oldFile := parsedFile.File
	newFile := logic.GetAnimeEpFilepath(parsedFile.AnimeEpisode(), "part")
	encodedFile := logic.GetAnimeEpFilepath(parsedFile.AnimeEpisode(), filepath.Ext(parsedFile.File))
	lockFile := logic.GetAnimeEpFilepath(parsedFile.AnimeEpisode(), "lock")

	fmt.Fprintf(w, "\tmove file\n\t    from: '%s'\n\t    to: '%s'\n", oldFile, newFile)

	if err := os.MkdirAll(filepath.Dir(newFile), os.ModePerm); err != nil {
		return err
	}

	if err := os.Chown(filepath.Dir(newFile), Uid, Gid); err != nil {
		return err
	}

	if _, err := os.Stat(newFile); err != nil && !errors.Is(err, os.ErrNotExist) {
		return err
	}

	inputFile, err := os.Open(oldFile)
	if err != nil {
		return err
	}
	defer inputFile.Close()

	outputFile, err := os.Create(newFile)
	if err != nil {
		return err
	}
	defer outputFile.Close()

	if err := os.Chown(newFile, Uid, Gid); err != nil {
		return err
	}

	written, err := io.Copy(outputFile, inputFile)
	if err != nil {
		return err
	}

	fmt.Fprintf(w, "\t    done (copied %s in %s)\n", FormatBytes(written), time.Since(start).Truncate(100*time.Millisecond))

	if err := EncodeVideo(w, parsedFile.Parser.FileEncoding, newFile, encodedFile); err != nil {
		return err
	}

	if err := os.Remove(oldFile); err != nil {
		return err
	}

	if err := os.Remove(lockFile); err != nil && !errors.Is(err, os.ErrNotExist) {
		return err
	}

	return nil
}

func DeleteOldAnimeEpisode(animeEp model.AnimeEpisode) {
	animeEpPath := logic.GetAnimeEpFilepath(animeEp, "*")
	files, err := filepath.Glob(animeEpPath)
	if err != nil {
		panic(logic.ErrInvalidGlobSyntax.Wrap(err, animeEpPath))
	}

	for _, file := range files {
		if filepath.Ext(file) == ".lock" {
			continue
		}

		if err := os.Remove(file); err != nil {
			adverr.Println(err)
		}
	}
}