package media_test

import (
	"bytes"
	"context"
	"database/sql"
	"errors"
	"io"
	"io/ioutil"
	"strings"
	"testing"
	"time"

	"git.netflux.io/rob/clipper/config"
	"git.netflux.io/rob/clipper/generated/mocks"
	"git.netflux.io/rob/clipper/generated/store"
	"git.netflux.io/rob/clipper/media"
	"github.com/google/uuid"
	"github.com/kkdai/youtube/v2"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/mock"
	"github.com/stretchr/testify/require"
	"go.uber.org/zap"
)

func TestGetAudioFromYoutube(t *testing.T) {
	const (
		videoID         = "abcdef12"
		inFixturePath   = "testdata/tone-44100-stereo-int16-30000ms.raw"
		inFixtureLen    = int64(5_292_000)
		inFixtureFrames = inFixtureLen / 4 // stereo-int16
	)

	ctx := context.Background()
	mediaSetID := uuid.New()
	mediaSet := store.MediaSet{
		ID:                mediaSetID,
		YoutubeID:         videoID,
		AudioYoutubeItag:  123,
		AudioChannels:     2,
		AudioFramesApprox: inFixtureFrames,
	}

	video := &youtube.Video{
		ID:      videoID,
		Formats: []youtube.Format{{ItagNo: 123, FPS: 0, AudioChannels: 2}},
	}

	t.Run("NOK,ErrorFetchingMediaSet", func(t *testing.T) {
		var mockStore mocks.Store
		mockStore.On("GetMediaSet", mock.Anything, mediaSetID).Return(store.MediaSet{}, errors.New("db went boom"))
		service := media.NewMediaSetService(&mockStore, nil, nil, nil, config.Config{}, zap.NewNop().Sugar())
		_, err := service.GetPeaks(ctx, mediaSetID, 10)
		assert.EqualError(t, err, "error getting media set: db went boom")
	})

	t.Run("NOK,ErrorFetchingStream", func(t *testing.T) {
		var mockStore mocks.Store
		mockStore.On("GetMediaSet", ctx, mediaSetID).Return(mediaSet, nil)
		var youtubeClient mocks.YoutubeClient
		youtubeClient.On("GetVideoContext", ctx, mediaSet.YoutubeID).Return(video, nil)
		youtubeClient.On("GetStreamContext", ctx, video, &video.Formats[0]).Return(nil, int64(0), errors.New("uh oh"))

		service := media.NewMediaSetService(&mockStore, &youtubeClient, nil, nil, config.Config{}, zap.NewNop().Sugar())
		_, err := service.GetPeaks(ctx, mediaSetID, 10)
		assert.EqualError(t, err, "error fetching stream: uh oh")
	})

	t.Run("NOK,ErrorBuildingProgressReader", func(t *testing.T) {
		invalidMediaSet := mediaSet
		invalidMediaSet.AudioChannels = 0
		var mockStore mocks.Store
		mockStore.On("GetMediaSet", mock.Anything, mediaSetID).Return(invalidMediaSet, nil)

		var youtubeClient mocks.YoutubeClient
		youtubeClient.On("GetVideoContext", ctx, mediaSet.YoutubeID).Return(video, nil)
		youtubeClient.On("GetStreamContext", ctx, video, &video.Formats[0]).Return(nil, int64(0), nil)

		service := media.NewMediaSetService(&mockStore, &youtubeClient, nil, nil, config.Config{}, zap.NewNop().Sugar())
		_, err := service.GetPeaks(ctx, mediaSetID, 10)
		assert.EqualError(t, err, "error building progress reader: error creating audio progress reader (framesExpected = 1323000, channels = 0, numBins = 10)")
	})

	t.Run("NOK,UploadError", func(t *testing.T) {
		var mockStore mocks.Store
		mockStore.On("GetMediaSet", mock.Anything, mediaSetID).Return(mediaSet, nil)
		mockStore.On("SetEncodedAudioUploaded", ctx, mock.Anything).Return(mediaSet, nil)

		var youtubeClient mocks.YoutubeClient
		youtubeClient.On("GetVideoContext", ctx, mediaSet.YoutubeID).Return(video, nil)
		youtubeClient.On("GetStreamContext", ctx, video, &video.Formats[0]).Return(io.NopCloser(bytes.NewReader(nil)), int64(0), nil)

		var fileStore mocks.FileStore
		fileStore.On("PutObject", ctx, mock.Anything, mock.Anything, "audio/raw").Return(int64(0), errors.New("error uploading raw audio"))
		fileStore.On("PutObject", ctx, mock.Anything, mock.Anything, "audio/opus").Return(int64(0), nil)
		fileStore.On("GetURL", ctx, mock.Anything).Return("", nil)

		cmd := helperCommand(t, "", inFixturePath, "", 0)
		service := media.NewMediaSetService(&mockStore, &youtubeClient, &fileStore, cmd, config.Config{}, zap.NewNop().Sugar())
		stream, err := service.GetPeaks(ctx, mediaSetID, 10)
		assert.NoError(t, err)

		_, err = stream.Next()
		assert.EqualError(t, err, "error waiting for progress: error uploading raw audio: error uploading raw audio")
	})

	t.Run("NOK,FFmpegError", func(t *testing.T) {
		var mockStore mocks.Store
		mockStore.On("GetMediaSet", mock.Anything, mediaSetID).Return(mediaSet, nil)
		mockStore.On("SetEncodedAudioUploaded", ctx, mock.Anything).Return(mediaSet, nil)
		mockStore.On("SetRawAudioUploaded", ctx, mock.Anything).Return(mediaSet, nil)

		var youtubeClient mocks.YoutubeClient
		youtubeClient.On("GetVideoContext", ctx, mediaSet.YoutubeID).Return(video, nil)
		youtubeClient.On("GetStreamContext", ctx, video, &video.Formats[0]).Return(io.NopCloser(strings.NewReader("some audio")), int64(0), nil)

		var fileStore mocks.FileStore
		fileStore.On("PutObject", ctx, mock.Anything, mock.Anything, mock.Anything).Return(int64(0), nil)
		fileStore.On("GetURL", ctx, mock.Anything).Return("", nil)

		cmd := helperCommand(t, "", inFixturePath, "oh no", 101)
		service := media.NewMediaSetService(&mockStore, &youtubeClient, &fileStore, cmd, config.Config{}, zap.NewNop().Sugar())
		stream, err := service.GetPeaks(ctx, mediaSetID, 10)
		assert.NoError(t, err)

		_, err = stream.Next()
		assert.EqualError(t, err, "error waiting for progress: error waiting for command: exit status 101, output: oh no")
	})

	t.Run("OK", func(t *testing.T) {
		// Mock Store
		var mockStore mocks.Store
		mockStore.On("GetMediaSet", ctx, mediaSetID).Return(mediaSet, nil)
		mockStore.On("SetRawAudioUploaded", ctx, mock.MatchedBy(func(p store.SetRawAudioUploadedParams) bool {
			return p.ID == mediaSetID && p.AudioFrames.Int64 == inFixtureFrames
		})).Return(mediaSet, nil)
		mockStore.On("SetEncodedAudioUploaded", ctx, mock.MatchedBy(func(p store.SetEncodedAudioUploadedParams) bool {
			return p.ID == mediaSetID
		})).Return(mediaSet, nil)
		defer mockStore.AssertExpectations(t)

		// Mock YoutubeClient
		encodedContent := "this is an opus stream"
		reader := io.NopCloser(strings.NewReader(encodedContent))
		var youtubeClient mocks.YoutubeClient
		youtubeClient.On("GetVideoContext", ctx, mediaSet.YoutubeID).Return(video, nil)
		youtubeClient.On("GetStreamContext", ctx, video, &video.Formats[0]).Return(reader, int64(len(encodedContent)), nil)
		defer youtubeClient.AssertExpectations(t)

		// Mock FileStore
		// It is necessary to consume the readers passed into the mocks to avoid IO
		// errors. Since we're doing that we can also assert the content that is
		// passed to them is as expected.
		url := "https://www.example.com/foo"
		var fileStore mocks.FileStore
		fileStore.On("PutObject", ctx, "media_sets/"+mediaSetID.String()+"/audio.opus", mock.Anything, "audio/opus").
			Run(func(args mock.Arguments) {
				readContent, err := ioutil.ReadAll(args[2].(io.Reader))
				require.NoError(t, err)
				assert.Equal(t, encodedContent, string(readContent))
			}).
			Return(int64(len(encodedContent)), nil)
		fileStore.On("PutObject", ctx, "media_sets/"+mediaSetID.String()+"/audio.raw", mock.Anything, "audio/raw").
			Run(func(args mock.Arguments) {
				n, err := io.Copy(io.Discard, args[2].(io.Reader))
				require.NoError(t, err)
				assert.Equal(t, inFixtureLen, n)
			}).
			Return(inFixtureLen, nil)
		fileStore.On("GetURL", ctx, "media_sets/"+mediaSetID.String()+"/audio.opus").Return(url, nil)
		defer fileStore.AssertExpectations(t)

		numBins := 10
		cmd := helperCommand(t, "ffmpeg -hide_banner -loglevel error -i - -f s16le -ar 48000 -acodec pcm_s16le -", inFixturePath, "", 0)
		service := media.NewMediaSetService(&mockStore, &youtubeClient, &fileStore, cmd, config.Config{}, zap.NewNop().Sugar())
		stream, err := service.GetPeaks(ctx, mediaSetID, numBins)
		require.NoError(t, err)

		assertConsumeStream(t, numBins, url, stream)
	})
}

func TestGetPeaksFromFileStore(t *testing.T) {
	const (
		inFixturePath = "testdata/tone-44100-stereo-int16-30000ms.raw"
		inFixtureLen  = 5_292_000
	)

	ctx := context.Background()
	logger := zap.NewNop().Sugar()
	mediaSetID := uuid.New()
	mediaSet := store.MediaSet{
		ID:                       mediaSetID,
		AudioChannels:            2,
		AudioFrames:              sql.NullInt64{Int64: 1_323_000, Valid: true},
		AudioRawS3Key:            sql.NullString{String: "raw audio key", Valid: true},
		AudioRawS3UploadedAt:     sql.NullTime{Time: time.Now(), Valid: true},
		AudioEncodedS3Key:        sql.NullString{String: "encoded audio key", Valid: true},
		AudioEncodedS3UploadedAt: sql.NullTime{Time: time.Now(), Valid: true},
	}

	t.Run("NOK,ErrorFetchingMediaSet", func(t *testing.T) {
		var mockStore mocks.Store
		mockStore.On("GetMediaSet", mock.Anything, mediaSetID).Return(store.MediaSet{}, errors.New("db went boom"))
		service := media.NewMediaSetService(&mockStore, nil, nil, nil, config.Config{}, logger)
		_, err := service.GetPeaks(ctx, mediaSetID, 10)
		assert.EqualError(t, err, "error getting media set: db went boom")
	})

	t.Run("NOK,ErrorGettingObjectFromFileStore", func(t *testing.T) {
		var mockStore mocks.Store
		mockStore.On("GetMediaSet", mock.Anything, mediaSetID).Return(mediaSet, nil)
		defer mockStore.AssertExpectations(t)

		var fileStore mocks.FileStore
		fileStore.On("GetObject", mock.Anything, "raw audio key").Return(nil, errors.New("boom"))

		service := media.NewMediaSetService(&mockStore, nil, &fileStore, nil, config.Config{}, logger)
		_, err := service.GetPeaks(ctx, mediaSetID, 10)
		require.EqualError(t, err, "error getting object from file store: boom")
	})

	t.Run("NOK,ErrorGettingObjectURL", func(t *testing.T) {
		var mockStore mocks.Store
		mockStore.On("GetMediaSet", mock.Anything, mediaSetID).Return(mediaSet, nil)
		defer mockStore.AssertExpectations(t)

		var fileStore mocks.FileStore
		reader := fixtureReader(t, inFixturePath, inFixtureLen)
		fileStore.On("GetObject", mock.Anything, "raw audio key").Return(reader, nil)
		fileStore.On("GetURL", mock.Anything, "encoded audio key").Return("", errors.New("network error"))
		defer fileStore.AssertExpectations(t)

		service := media.NewMediaSetService(&mockStore, nil, &fileStore, nil, config.Config{}, logger)
		stream, err := service.GetPeaks(ctx, mediaSetID, 10)
		require.NoError(t, err)

		var hadError bool
		for {
			_, err := stream.Next()
			if err != nil {
				hadError = true
				assert.EqualError(t, err, "error waiting for progress: error generating object URL: network error")
				break
			}
		}
		assert.True(t, hadError)
	})

	t.Run("OK", func(t *testing.T) {
		var mockStore mocks.Store
		mockStore.On("GetMediaSet", mock.Anything, mediaSetID).Return(mediaSet, nil)
		defer mockStore.AssertExpectations(t)

		var fileStore mocks.FileStore
		url := "https://www.example.com/foo"
		reader := fixtureReader(t, inFixturePath, inFixtureLen)
		fileStore.On("GetObject", mock.Anything, "raw audio key").Return(reader, nil)
		fileStore.On("GetURL", mock.Anything, "encoded audio key").Return(url, nil)
		defer fileStore.AssertExpectations(t)

		numBins := 10
		service := media.NewMediaSetService(&mockStore, nil, &fileStore, nil, config.Config{}, logger)
		stream, err := service.GetPeaks(ctx, mediaSetID, numBins)
		require.NoError(t, err)

		assertConsumeStream(t, numBins, url, stream)
	})
}

// assertConsumeStream asserts that the stream produced by both the
// from-youtube and from-filestore flows is identical.
func assertConsumeStream(t *testing.T, expBins int, expURL string, stream media.GetPeaksProgressReader) {
	lastPeaks := make([]int16, 2) // stereo
	var (
		count               int
		lastPercentComplete float32
		lastURL             string
	)

	for {
		progress, err := stream.Next()
		if err != io.EOF {
			require.NoError(t, err)
		}

		assert.Len(t, progress.Peaks, 2)
		assert.GreaterOrEqual(t, progress.PercentComplete, lastPercentComplete)
		lastPercentComplete = progress.PercentComplete
		lastURL = progress.URL

		if err == io.EOF {
			break
		}

		// the fixture is a tone gradually increasing in amplitude:
		assert.Greater(t, progress.Peaks[0], lastPeaks[0])
		assert.Greater(t, progress.Peaks[1], lastPeaks[1])
		lastPeaks = progress.Peaks
		count++
	}

	assert.Equal(t, float32(100), lastPercentComplete)
	assert.Equal(t, []int16{32_767, 32_766}, lastPeaks)
	assert.Equal(t, expBins, count)
	assert.Equal(t, expURL, lastURL)
}