package imageprocessor

import (
	"bytes"
	"errors"
	"io"
	"testing"

	"sneak.berlin/go/pixa/internal/imagerequest"
)

// TestImageProcessor_LoadsEachSourceFormat verifies that an image in each of
// the six source formats, saved by the processor itself, is loaded and saved
// again in its own format (orig).
func TestImageProcessor_LoadsEachSourceFormat(t *testing.T) {
	t.Parallel()

	proc := New(Params{MaxInputBytes: 50 << 20, MaxConcurrentProcessing: 1})

	for _, format := range []imagerequest.Format{
		imagerequest.FormatJPEG, imagerequest.FormatPNG, imagerequest.FormatGIF,
		imagerequest.FormatWebP, imagerequest.FormatAVIF, imagerequest.FormatJXL,
	} {
		saved, err := proc.Process(t.Context(),
			bytes.NewReader(createTestPNG(t, 20, 20)), imagerequest.FormatPNG,
			&imagerequest.Transform{Format: format})
		if err != nil {
			t.Fatalf("saving the test image as %s: %v", format, err)
		}

		source, err := io.ReadAll(saved.Content)
		if err != nil {
			t.Fatalf("reading the %s image: %v", format, err)
		}

		result, err := proc.Process(t.Context(), bytes.NewReader(source), format,
			&imagerequest.Transform{Format: imagerequest.FormatOriginal})
		if err != nil {
			t.Errorf("orig of the %s image: %v", format, err)

			continue
		}

		t.Logf("orig of the %s image: %s", format, result.ContentType)

		if result.ContentType != format.MIMEType() {
			t.Errorf("orig of the %s image is %s, want %s",
				format, result.ContentType, format.MIMEType())
		}
	}
}

// TestImageProcessor_NotASourceFormatRefused verifies that a source format
// other than the six, such as orig, auto or none, is refused with
// ErrUnsupportedInputFormat. The input is text, which libvips reads as no
// format.
func TestImageProcessor_NotASourceFormatRefused(t *testing.T) {
	t.Parallel()

	proc := New(Params{MaxInputBytes: 50 << 20, MaxConcurrentProcessing: 1})

	for _, sourceFormat := range []imagerequest.Format{
		imagerequest.FormatOriginal, imagerequest.FormatAuto, "",
	} {
		result, err := proc.Process(t.Context(),
			bytes.NewReader([]byte("this is text, not an image")), sourceFormat,
			&imagerequest.Transform{Format: imagerequest.FormatJPEG})
		t.Logf("source format %q: error = %v", sourceFormat, err)

		if result != nil || !errors.Is(err, ErrUnsupportedInputFormat) {
			t.Errorf("Process() with source format %q = %v, error %v; want %v",
				sourceFormat, result, err, ErrUnsupportedInputFormat)
		}
	}
}