package main

import (
	"database/sql"
	"encoding/binary"
	"encoding/hex"
	"encoding/json"
	"errors"
	"flag"
	"fmt"
	"git.gammaspectra.live/S.O.N.G/Hibiki/panako"
	"git.gammaspectra.live/S.O.N.G/Hibiki/utilities/audio"
	"git.gammaspectra.live/S.O.N.G/Hibiki/utilities/audio/format/flac"
	"git.gammaspectra.live/S.O.N.G/Hibiki/utilities/audio/format/mp3"
	"git.gammaspectra.live/S.O.N.G/Hibiki/utilities/audio/format/opus"
	"git.gammaspectra.live/S.O.N.G/Hibiki/utilities/specializedstore"
	"git.gammaspectra.live/S.O.N.G/METANOIA/database"
	"git.gammaspectra.live/S.O.N.G/METANOIA/store"
	"git.gammaspectra.live/S.O.N.G/MakyuuIchaival/httputils"
	"git.gammaspectra.live/S.O.N.G/MakyuuIchaival/tlsutils"
	"github.com/dhowden/tag"
	"github.com/minio/sha256-simd"
	"io"
	"io/ioutil"
	"log"
	"net/http"
	"os"
	"path"
	"path/filepath"
	"runtime"
	"sort"
	"strings"
	"sync"
	"time"
)

var panakoInstance *panako.Instance
var printStrategy *panako.Strategy
var db *database.Database
var resourceCreationMutex sync.Mutex

var fdlimit chan bool

func OpenFileWithLimit(filePath string) (*os.File, error) {
	fdlimit <- true
	f, err := os.Open(filePath)

	if err != nil {
		<-fdlimit
	}

	return f, err
}
func CloseFileWithLimit(f *os.File, force bool) error {
	err := f.Close()
	if err == nil || force {
		<-fdlimit
	}
	return err
}

func GetMimeTypeFromExtension(ext string) string {

	if len(ext) > 0 {
		switch strings.ToLower(ext[1:]) {

		//Audio types
		case "flac":
			return "audio/flac"
		case "mp3":
			return "audio/mpeg;codecs=mp3"
		case "m4a":
			return "audio/mp4"
		case "mka":
			return "audio/x-matroska"
		case "ogg":
			return "audio/ogg"
		case "opus":
			return "audio/opus"
		case "tta":
			return "audio/tta"
		case "aac":
			return "audio/aac"
		case "alac":
			return "audio/alac"
		case "wav":
			return "audio/wav"
		case "ape":
			return "audio/ape"

		//Image types
		case "png":
			return "image/png"
		case "jfif":
			fallthrough
		case "jpeg":
			fallthrough
		case "jpg":
			return "image/jpeg"
		case "gif":
			return "image/gif"
		case "svg":
			return "image/svg+xml"
		case "tiff":
			fallthrough
		case "tif":
			return "image/tiff"
		case "webp":
			return "image/webp"
		case "bmp":
			return "image/bmp"

		//Text types
		case "txt":
			return "text/plain"
		case "log":
			return "text/x-log"
		case "accurip":
			return "text/x-accurip"
		case "cue":
			return "text/x-cue"
		case "toc":
			return "text/x-toc"

		//Text subtitles
		case "lrc":
			return "text/x-subtitle-lrc"
		case "ssa":
			return "text/x-subtitle-ssa"
		case "ass":
			return "text/x-subtitle-ass"
		case "srt":
			return "text/x-subtitle-subrip"

		//Web types
		case "js":
			return "text/javascript"
		case "wasm":
			return "application/wasm"
		case "html":
			return "text/html"
		case "css":
			return "text/css"
		case "ttf":
			return "font/ttf"
		case "otf":
			return "font/otf"
		case "woff":
			return "font/woff"
		case "woff2":
			return "font/woff2"

		}
	}

	return "application/octet-stream"
}

type PendingTransaction struct {
	Tx        *sql.Tx
	WaitGroup sync.WaitGroup
}

func AddFolderToDatabase(release *database.Release, tx *PendingTransaction, pathEntry string) {
	defer tx.WaitGroup.Done()
	entries, err := ioutil.ReadDir(pathEntry)
	if err != nil {
		return
	}
	for _, entry := range entries {
		if entry.IsDir() {
			tx.WaitGroup.Add(1)
			AddFolderToDatabase(release, tx, pathEntry+"/"+entry.Name())
		} else {
			ext := path.Ext(entry.Name())
			mime := GetMimeTypeFromExtension(ext)

			if mime == "application/octet-stream" { //Generic, do not store
				continue
			}
			isAudio := mime[0:6] == "audio/"
			isText := mime[0:5] == "text/" && mime != "text/html" && mime != "text/css" && mime != "text/javascript"
			isImage := mime[0:6] == "image/"

			if isAudio {
				tx.WaitGroup.Add(1)
				AddAudioToDatabase(release, tx, entry.Size(), mime, pathEntry+"/"+entry.Name())
			} else if isText || isImage {
				tx.WaitGroup.Add(1)
				AddFileToDatabase(release, tx, entry.Size(), mime, pathEntry+"/"+entry.Name())
			}
		}
	}
}

func AddFileToDatabase(release *database.Release, tx *PendingTransaction, size int64, mime, pathEntry string) {
	defer tx.WaitGroup.Done()
}

func AddAudioToDatabase(release *database.Release, tx *PendingTransaction, size int64, mime, pathEntry string) {
	log.Printf("handling %s", pathEntry)
	defer tx.WaitGroup.Done()

	resource := database.GetResourceFromDatabaseByPath(db, pathEntry)
	if resource != nil && len(resource.GetReleases()) > 0 {
		return
	}

	f, err := OpenFileWithLimit(pathEntry)
	if err != nil { //TODO
		log.Panic(err)
		return
	}

	tx.WaitGroup.Add(1)
	go func() {
		defer tx.WaitGroup.Done()
		defer CloseFileWithLimit(f, true)

		hasher := sha256.New()
		io.Copy(hasher, f)

		var hash database.ResourceHashIdentifier
		copy(hash[:], hasher.Sum(nil))

		resourceCreationMutex.Lock()
		resource = database.GetResourceFromDatabaseByHash(db, hash)
		var exists = resource != nil && len(resource.GetReleases()) > 0

		if resource == nil {
			//insert
			resource = database.InsertResourceToDatabase(db, hash, size, []byte(pathEntry), mime)
		}
		resourceCreationMutex.Unlock()

		if resource == nil {
			log.Panic(errors.New("failed to create resource")) //TODO: not panic
		}

		log.Printf("hash %x path %s", hash, pathEntry)
		f.Seek(0, 0)
		meta, err := tag.ReadFrom(f)
		if err == nil { //no metadata
			log.Print(meta)
		} else {
			log.Print(err)
			err = nil
		}
		f.Seek(0, 0)

		defer resource.AddRelease(release)

		if !exists {
			//Fingerprint

			f.Seek(0, 0)

			var stream *audio.Stream
			switch mime { //TODO: change this to scan style
			case "audio/flac":
				//TODO: add CRC32 scan
				flacFormat := flac.NewFormat()
				stream, err = flacFormat.Open(f, panakoInstance.BlockSize)

			case "audio/mpeg;codecs=mp3":
				mp3Format := mp3.NewFormat()
				stream, err = mp3Format.Open(f, panakoInstance.BlockSize)

			case "audio/ogg":
				fallthrough
			case "audio/opus":
				opusFormat := opus.NewFormat()
				stream, err = opusFormat.Open(f, panakoInstance.BlockSize)
			}

			if err != nil { //cannot decode
				log.Printf("error for %s: %s", pathEntry, err)
				return //TODO
			}

			if stream == nil { //no known decoder
				log.Printf("error for %s: no known decoder", pathEntry)
				return
			}

			printStrategy.StoreStream(panako.ResourceId(resource.GetId()), stream)

			log.Printf("finished fingerprinting %s", pathEntry)
		}

	}()

}

func main() {
	pgConnStr := flag.String("connstr", "", "Postgres connection string for postgres database")
	printDbOption := flag.String("printdb", "", "Fingerprint database path. Fast storage recommended.")
	cmdOption := flag.String("cmd", "add", "Command: add, query, server")
	pathOption := flag.String("path", "", "Path for commands.")
	listenAddress := flag.String("listen", ":7777", "Address/port to lisent on.")
	certificatePath := flag.String("certificate", "", "Path to SSL certificate file.")
	keypairPath := flag.String("keypair", "", "Path to SSL key file.")
	sniAddressOption := flag.String("sni", "", "Define SNI address if desired. Empty will serve any requests regardless.")
	fdlimitOption := flag.Int("fdlimit", 128, "Set file operation and process limit.")
	goProcs := flag.Int("maxprocs", runtime.NumCPU(), "Set GOMAXPROCS.")

	flag.Parse()

	fdlimit = make(chan bool, *fdlimitOption)
	runtime.GOMAXPROCS(*goProcs)

	var err error

	if *printDbOption == "" || *pgConnStr == "" {
		flag.PrintDefaults()
		os.Exit(0)
	}

	db, err = database.OpenDatabase(*pgConnStr)
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()

	//TODO: check if mutex is correct!

	panakoInstance = panako.NewDefaultPackedInstance()

	if *cmdOption == "add" {
		printDb, err := store.NewAppendStore(*printDbOption, true, true)
		if err != nil {
			log.Fatal(err)
		}

		defer printDb.Close()

		printStrategy = panakoInstance.GetStrategy(printDb)

		var release *database.Release
		releases := database.GetReleasesFromDatabaseByIdentifier(db, "test")
		if len(releases) == 0 {
			release = database.InsertReleaseToDatabase(db, []string{"test"})
		} else {
			release = releases[0]
		}

		tx, err := db.GetTx()
		if err != nil {
			log.Panic(err)
		}

		pending := &PendingTransaction{
			Tx: tx,
		} //TODO

		filePath, err := filepath.Abs(*pathOption)
		if err != nil {
			log.Panic(err)
		}
		pending.WaitGroup.Add(1)
		AddFolderToDatabase(release, pending, filePath)

		pending.WaitGroup.Wait()
	} else if *cmdOption == "query" {
		printDb, err := specializedstore.NewBadgerStore(*printDbOption, true, true, 100000)
		if err != nil {
			log.Fatal(err)
		}

		defer printDb.Close()

		printStrategy = panakoInstance.GetStrategy(printDb)

		pathEntry, err := filepath.Abs(*pathOption)
		if err != nil {
			log.Panic(err)
		}
		f, err := OpenFileWithLimit(pathEntry)
		if err != nil { //TODO
			log.Panic(err)
			return
		}

		var stream *audio.Stream
		switch GetMimeTypeFromExtension(path.Ext(pathEntry)) { //TODO: change this to scan style
		case "audio/flac":
			//TODO: add CRC32 scan
			flacFormat := flac.NewFormat()
			stream, err = flacFormat.Open(f, panakoInstance.BlockSize)

		case "audio/mpeg;codecs=mp3":
			mp3Format := mp3.NewFormat()
			stream, err = mp3Format.Open(f, panakoInstance.BlockSize)

		case "audio/ogg":
			fallthrough
		case "audio/opus":
			opusFormat := opus.NewFormat()
			stream, err = opusFormat.Open(f, panakoInstance.BlockSize)
		}

		if err != nil { //cannot decode
			log.Panic(err) //TODO: not panic
		}

		if stream == nil { //no known decoder
			log.Panic(fmt.Errorf("no known decoder for %s", pathEntry))
		}

		start := time.Now()
		prints := printStrategy.StreamToFingerprints(stream)
		printT := time.Now()
		results := printStrategy.QueryFingerprints(prints)
		resultT := time.Now()

		log.Printf("decode+fingerprint = %dms, query = %dms", printT.Sub(start).Milliseconds(), resultT.Sub(printT).Milliseconds())
		for _, result := range results {
			log.Printf("result %#v\n", result)
			resource := database.GetResourceFromDatabase(db, int64(result.ReferenceResourceId))
			if resource != nil {
				log.Printf("matched %s score %d\n", resource.GetPath(), result.Score)
			}
		}

		log.Printf("finished querying %s", pathEntry)
	} else if *cmdOption == "server" {
		printDb, err := specializedstore.NewBadgerStore(*printDbOption, true, true, 100000)
		if err != nil {
			log.Fatal(err)
		}

		defer printDb.Close()

		printStrategy = panakoInstance.GetStrategy(printDb)

		tlsConfiguration, err := tlsutils.NewTLSConfiguration(*certificatePath, *keypairPath, *sniAddressOption)
		if err != nil {
			log.Fatal(err)
		}

		filePath, err := filepath.Abs(*pathOption)
		if err != nil {
			log.Panic(err)
		}

		server := &httputils.Server{
			ListenAddress: *listenAddress,
			TLSConfig:     tlsConfiguration,
			EnableHTTP2:   false,
			EnableHTTP3:   false,
			Handler: func(ctx *httputils.RequestContext) {
				if len(ctx.GetRequestHeader("Host")) > 0 && ctx.GetRequestHeader("Host") == ctx.GetTLSServerName() { //Prevents rebinding / DNS stuff
					ctx.SetResponseCode(http.StatusNotFound)
					return
				}

				if ctx.IsGet() || ctx.IsHead() {
					pathName := ctx.GetPath()
					if pathName == "/" {
						pathName = "/index.html"
					}

					ctx.SetResponseHeader("Content-Type", GetMimeTypeFromExtension(path.Ext(filePath+pathName)))
					ctx.ServeFile(filePath + pathName)
				} else if ctx.IsPost() {
					if ctx.GetPath() == "/query" {
						setOtherHeaders(ctx)
						setCORSHeaders(ctx)
						var records []panako.StoreRecord
						body := ctx.GetBody()

						for {
							var hash uint32
							err := binary.Read(body, binary.BigEndian, &hash)
							if err != nil {
								break
							}
							var packed uint32
							err = binary.Read(body, binary.LittleEndian, &packed)
							if err != nil {
								ctx.SetResponseCode(http.StatusBadRequest)
								return
							}

							records = append(records, panako.NewStoreRecordFromCompactPacked(0, hash, packed))
						}

						type Result struct {
							MatchId  int64  `json:"matchId"`
							FileHash string `json:"fileHash"`
							FileName string `json:"fileName"`
							FileSize int    `json:"fileSize"`

							MatchStart float64 `json:"matchStart"`
							MatchEnd   float64 `json:"matchEnd"`

							QueryStart float64 `json:"queryStart"`
							QueryEnd   float64 `json:"queryEnd"`

							Segment                     int     `json:"segment"`
							Score                       int     `json:"score"`
							TimeFactor                  float64 `json:"timeFactor"`
							FrequencyFactor             float64 `json:"frequencyFactor"`
							PercentOfSecondsWithMatches float64 `json:"percentMatch"`
						}

						results := make([]Result, 0, 1)

						for _, m := range printStrategy.QueryStoreRecords(records) {
							resource := database.GetResourceFromDatabase(db, int64(m.ReferenceResourceId))
							if resource == nil {
								continue
							}

							results = append(results, Result{
								MatchId:  resource.GetId(),
								FileHash: hex.EncodeToString(resource.GetHash().ToBytes()),
								FileName: path.Base(string(resource.GetPath())),
								FileSize: int(resource.GetSize()),

								MatchStart: m.ReferenceStart.Seconds(),
								MatchEnd:   m.ReferenceStop.Seconds(),

								QueryStart: m.QueryStart.Seconds(),
								QueryEnd:   m.QueryStop.Seconds(),
								Segment:    -1,

								Score:                       m.Score,
								TimeFactor:                  m.TimeFactor,
								FrequencyFactor:             m.FrequencyFactor,
								PercentOfSecondsWithMatches: m.PercentOfSecondsWithMatches,
							})
						}

						if len(records) > 0 {
							splitBy := len(records) / 10

							for i := 0; i < len(records); i += splitBy {
								if i+splitBy >= len(records) {
									continue
								}
								for _, m := range printStrategy.QueryStoreRecords(records[i : i+splitBy]) {

									exists := false
									for _, v := range results {
										if v.MatchId == int64(m.ReferenceResourceId) {
											exists = true
											break
										}
									}

									if exists {
										continue
									}

									resource := database.GetResourceFromDatabase(db, int64(m.ReferenceResourceId))
									if resource == nil {
										continue
									}

									results = append(results, Result{
										MatchId:  resource.GetId(),
										FileHash: hex.EncodeToString(resource.GetHash().ToBytes()),
										FileName: path.Base(string(resource.GetPath())),
										FileSize: int(resource.GetSize()),

										MatchStart: m.ReferenceStart.Seconds(),
										MatchEnd:   m.ReferenceStop.Seconds(),

										QueryStart: m.QueryStart.Seconds(),
										QueryEnd:   m.QueryStop.Seconds(),
										Segment:    i,

										Score:                       m.Score,
										TimeFactor:                  m.TimeFactor,
										FrequencyFactor:             m.FrequencyFactor,
										PercentOfSecondsWithMatches: m.PercentOfSecondsWithMatches,
									})
								}
							}
						}

						sort.Slice(results, func(i, j int) bool {
							return results[j].Score < results[i].Score
						})

						ctx.SetResponseHeader("Content-Type", "application/json")

						b, _ := json.MarshalIndent(results, "", " ")
						ctx.ServeBytes(b)
						ctx.SetResponseCode(http.StatusOK)
					} else {
						ctx.SetResponseCode(http.StatusNotFound)
					}
				} else if ctx.IsOptions() {
					setOtherHeaders(ctx)
					setCORSHeaders(ctx)
					ctx.SetResponseCode(http.StatusNoContent)
				} else {
					ctx.SetResponseCode(http.StatusNotImplemented)
				}
			},
			Debug: false,
		}

		server.Serve()
	}

}

func setOtherHeaders(ctx *httputils.RequestContext) {
	ctx.SetResponseHeader("Server", "METANOIA")
	ctx.SetResponseHeader("Vary", "Content-Encoding")
	ctx.SetResponseHeader("X-Content-Type-Options", "nosniff")
	ctx.SetResponseHeader("X-Robots-Tags", "noindex, nofollow, notranslate")
	ctx.SetResponseHeader("Referrer-Policy", "origin")
}
func setCORSHeaders(ctx *httputils.RequestContext) {
	ctx.SetResponseHeader("Access-Control-Allow-Credentials", "true")
	ctx.SetResponseHeader("Access-Control-Max-Age", "7200") //Firefox caps this to 86400, Chrome to 7200. Default is 5 seconds (!!!)
	ctx.SetResponseHeader("Access-Control-Allow-Methods", "GET,HEAD,POST,OPTIONS")
	ctx.SetResponseHeader("Access-Control-Allow-Headers", "DNT,ETag,Origin,Accept,Accept-Language,X-Requested-With,Range")
	ctx.SetResponseHeader("Access-Control-Allow-Origin", "*")
	ctx.SetResponseHeader("Access-Control-Expose-Headers", "*")

	//CORP, COEP, COOP
	ctx.SetResponseHeader("Cross-Origin-Embedder-Policy", "require-corp")
	ctx.SetResponseHeader("Cross-Origin-Resource-Policy", "cross-origin")
	ctx.SetResponseHeader("Cross-Origin-Opener-Policy", "unsafe-none")
}