package main

import (
	"compress/bzip2"
	"compress/flate"
	"compress/gzip"
	"errors"
	"fmt"
	"git.gammaspectra.live/S.O.N.G/Ignite/frame"
	"github.com/ulikunitz/xz"
	"io"
	"log"
	"maps"
	"net/http"
	"os"
	"time"
)

func handleDecompress(contentEncoding string, reader io.ReadCloser) (io.ReadCloser, error) {
	var err error
	switch contentEncoding {
	case "gzip":
		reader, err = gzip.NewReader(reader)
		if err != nil {
			return nil, err
		}
	case "bzip2":
		reader = io.NopCloser(bzip2.NewReader(reader))
	case "deflate":
		reader = flate.NewReader(reader)
	case "xz":
		r, err := xz.NewReader(reader)
		if err != nil {
			return nil, err
		}
		reader = io.NopCloser(r)
	case "":
		return reader, nil
	default:
		return nil, errors.New("unsupported encoding")
	}
	return reader, nil
}

func encodeFromReader(reader io.ReadCloser, job *Job, inputMimeType string, w http.ResponseWriter) {
	defer reader.Close()

	d := GetDecoderByMimeType(inputMimeType)
	if d == nil {
		//try for generic reader
		d = GetDecoderByMimeType("*")
		if d == nil {
			w.WriteHeader(http.StatusBadRequest)
			return
		}
	}

	defer func() {
		log.Printf("[job %s] finished, took %s", job.Id, time.Now().Sub(time.Unix(int64(job.Status.Start.Load()), 0)))
	}()

	job.Status.Start.Store(uint64(time.Now().Unix()))
	job.Status.Read.Store(0)
	job.Status.Processed.Store(0)

	settings := make(map[string]any)
	maps.Copy(settings, job.Config.Decoder.Settings)

	if len(job.Config.Timecodes) > 0 {
		settings["timecodes"] = job.Config.Timecodes
	}

	decoder, err := d.New(reader, settings)
	if err != nil {
		job.Logger.Printf("[error]: %s", err.Error())
		w.Header().Set("x-encoder-error", "")
		w.Header().Set("x-decoder-error", err.Error())
		w.WriteHeader(http.StatusBadRequest)
		return
	}

	//check decoder frame properties match
	decProps := decoder.Properties()
	if decProps.Width != job.Config.Properties.Width ||
		decProps.Height != job.Config.Properties.Height ||
		decProps.ColorSpace != job.Config.Properties.ColorSpace ||
		decProps.FullColorRange != job.Config.Properties.FullColorRange ||
		decProps.TimeBase() != job.Config.Properties.TimeBase() {
		w.Header().Set("x-encoder-error", "")
		w.Header().Set("x-decoder-error", "mismatched config properties")
		w.WriteHeader(http.StatusBadRequest)
		return
	}

	mimeType := "application/octet-stream"
	if e := GetEncoder(job.Config.Encoder.Name); e != nil {
		mimeType = e.MimeType
	}

	w.Header().Set("Content-Type", mimeType)
	w.Header().Add("Trailer", "x-encoder-error, x-decoder-error")
	w.WriteHeader(http.StatusOK)
	job.Logger = log.New(os.Stderr, fmt.Sprintf("[job %s] ", job.Id), log.LstdFlags)
	err = job.Init(w)
	if err != nil {
		job.Logger.Printf("[error]: %s", err.Error())
		w.Header().Set("x-encoder-error", err.Error())
		w.Header().Set("x-decoder-error", "")
		return
	}
	defer job.Close()

	var f frame.Frame
	for {
		f, err = decoder.Decode()
		if err != nil {
			if errors.Is(err, io.EOF) {
				//we are done
				break
			}
			job.Logger.Printf("[error]: %s", err.Error())
			w.Header().Set("x-encoder-error", "")
			w.Header().Set("x-decoder-error", err.Error())
			return
		}
		job.Status.Read.Add(1)

		err = job.Encoder.Encode(f)
		if err != nil {
			job.Logger.Printf("[error]: %s", err.Error())
			w.Header().Set("x-encoder-error", err.Error())
			w.Header().Set("x-decoder-error", "")
			return
		}
		f.Return()
		job.Status.Processed.Add(1)
		//log.Printf("[job %s] %d", job.Id, job.Status.Read.Load())
	}

	err = job.Encoder.Flush()
	if err != nil {
		job.Logger.Printf("[error]: %s", err.Error())
		w.Header().Set("x-encoder-error", err.Error())
		w.Header().Set("x-decoder-error", "")
		return
	}
}