package audio_test

import (
	"context"
	"errors"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"git.d-ma.be/mathias/tapir/internal/adapters/audio"
)

func TestFFmpegToWAV_AsksForSixteenKilohertzMonoPCMAlways(t *testing.T) {
	// Always transcode, even when the input already is 16 kHz mono: a Teams export
	// often is, and the point is to not ASSUME (ADR-033). Records the argv.
	rec := filepath.Join(t.TempDir(), "argv")
	bin := stub(t, `printf '%s\n' "$@" > `+rec+`; : > "$(eval echo \${$#})"`)

	err := (&audio.FFmpeg{Bin: bin}).ToWAV(context.Background(), "/spool/in", filepath.Join(t.TempDir(), "out.wav"))

	require.NoError(t, err)
	raw, err := os.ReadFile(rec)
	require.NoError(t, err)
	argv := strings.Split(strings.TrimSpace(string(raw)), "\n")
	joined := " " + strings.Join(argv, " ") + " "
	for _, want := range []string{" -ac 1 ", " -ar 16000 ", " -c:a pcm_s16le ", " -vn ", " -i /spool/in "} {
		assert.Contains(t, joined, want)
	}
	assert.True(t, strings.HasSuffix(strings.TrimSpace(joined), "out.wav"), "the output path is the last argument")
}

func TestFFmpegToWAV_NonzeroExitIsAnErrorCarryingStderr(t *testing.T) {
	bin := stub(t, `echo "moov atom not found" >&2; exit 1`)

	err := (&audio.FFmpeg{Bin: bin}).ToWAV(context.Background(), "/in", filepath.Join(t.TempDir(), "o.wav"))

	require.Error(t, err)
	assert.Contains(t, err.Error(), "moov atom not found")
}

func TestFFmpegToWAV_ZeroExitWithNoOutputIsAnError(t *testing.T) {
	bin := stub(t, `exit 0`)

	err := (&audio.FFmpeg{Bin: bin}).ToWAV(context.Background(), "/in", filepath.Join(t.TempDir(), "never-written.wav"))

	require.Error(t, err)
}

func TestFFmpegToWAV_MissingBinaryIsAnError(t *testing.T) {
	err := (&audio.FFmpeg{Bin: filepath.Join(t.TempDir(), "no-ffmpeg")}).ToWAV(context.Background(), "/in", "/out.wav")

	require.Error(t, err)
	assert.False(t, errors.Is(err, context.Canceled))
}