package app

import (
	"bytes"
	"context"
	"image"
	"image/color"
	"image/png"
	"testing"

	"github.com/geo-platform/tenant-api/internal/shared/config"
)

func newTestChallengePNG(t *testing.T) []byte {
	t.Helper()
	img := image.NewRGBA(image.Rect(0, 0, 50, 25))
	orange := color.RGBA{R: 240, G: 130, B: 40, A: 255}
	// Four orange blocks emulate the four-digit captcha; digitocr only needs to
	// segment and match them, so exact glyphs are not required for this test.
	for d := 0; d < 4; d++ {
		x0 := 5 + d*10
		for y := 5; y < 21; y++ {
			for x := x0; x < x0+8; x++ {
				img.Set(x, y, orange)
			}
		}
	}
	var buf bytes.Buffer
	if err := png.Encode(&buf, img); err != nil {
		t.Fatalf("encode png: %v", err)
	}
	return buf.Bytes()
}

func TestDigitOCRChallengeResolverDecodesImage(t *testing.T) {
	resolver := DigitOCRMeijiequanChallengeCodeResolver{}
	code, err := resolver.ResolveCode(context.Background(), MeijiequanChallenge{
		Image:       newTestChallengePNG(t),
		ContentType: "image/png",
	})
	if err != nil {
		t.Fatalf("resolve code: %v", err)
	}
	if len(code) != meijiequanChallengeDigits {
		t.Fatalf("expected %d digit code, got %q", meijiequanChallengeDigits, code)
	}
	for _, r := range code {
		if r < '0' || r > '9' {
			t.Fatalf("expected numeric code, got %q", code)
		}
	}
}

func TestDigitOCRChallengeResolverRejectsEmptyImage(t *testing.T) {
	resolver := DigitOCRMeijiequanChallengeCodeResolver{}
	if _, err := resolver.ResolveCode(context.Background(), MeijiequanChallenge{}); err == nil {
		t.Fatal("expected error for empty challenge image")
	}
}

func TestNewMeijiequanClientDefaultsToDigitOCRResolver(t *testing.T) {
	client := NewMeijiequanClient(nil, config.MeijiequanConfig{})
	if _, ok := client.challengeResolver().(DigitOCRMeijiequanChallengeCodeResolver); !ok {
		t.Fatalf("expected digitocr resolver by default, got %T", client.challengeResolver())
	}
}