package windsurf

import "testing"

func TestFingerprintBefore_BackwardCompatibleForTextOnly(t *testing.T) {
	msgs := []ChatMessage{
		{Role: "user", Content: "hello"},
		{Role: "assistant", Content: "hi"},
		{Role: "user", Content: "again"},
	}
	// 无图场景 hash 必须与 ImageDigests=nil 时一致（向后兼容）
	fp := FingerprintBefore(msgs, "claude-opus-4-7", "key-A")
	if fp == "" {
		t.Fatal("unexpected empty fingerprint")
	}
}

func TestFingerprintBefore_DifferentImagesDiffer(t *testing.T) {
	base := []ChatMessage{
		{Role: "user", Content: "describe", ImageDigests: []ImageDigest{{MimeType: "image/png", SHA256: "aaa", ByteLen: 100}}},
		{Role: "assistant", Content: "ok"},
		{Role: "user", Content: "next"},
	}
	diffImg := []ChatMessage{
		{Role: "user", Content: "describe", ImageDigests: []ImageDigest{{MimeType: "image/png", SHA256: "bbb", ByteLen: 100}}},
		{Role: "assistant", Content: "ok"},
		{Role: "user", Content: "next"},
	}
	fp1 := FingerprintBefore(base, "claude-opus-4-7", "key-A")
	fp2 := FingerprintBefore(diffImg, "claude-opus-4-7", "key-A")
	if fp1 == fp2 {
		t.Errorf("expected different fingerprints when image sha256 differs")
	}
}

func TestFingerprintBefore_SameImageDifferentCaptionDiffers(t *testing.T) {
	a := []ChatMessage{
		{Role: "user", Content: "x", ImageDigests: []ImageDigest{{MimeType: "image/png", SHA256: "z", ByteLen: 10, Caption: "cat"}}},
		{Role: "assistant", Content: "ok"},
		{Role: "user", Content: "y"},
	}
	b := []ChatMessage{
		{Role: "user", Content: "x", ImageDigests: []ImageDigest{{MimeType: "image/png", SHA256: "z", ByteLen: 10, Caption: "dog"}}},
		{Role: "assistant", Content: "ok"},
		{Role: "user", Content: "y"},
	}
	fp1 := FingerprintBefore(a, "claude-opus-4-7", "key-A")
	fp2 := FingerprintBefore(b, "claude-opus-4-7", "key-A")
	if fp1 == fp2 {
		t.Errorf("expected different fingerprints when caption differs")
	}
}

func TestFingerprintBefore_NoImagesSameAsAbsent(t *testing.T) {
	a := []ChatMessage{
		{Role: "user", Content: "hello"},
		{Role: "assistant", Content: "hi"},
		{Role: "user", Content: "again"},
	}
	b := []ChatMessage{
		{Role: "user", Content: "hello", Images: nil, ImageDigests: nil},
		{Role: "assistant", Content: "hi"},
		{Role: "user", Content: "again"},
	}
	if FingerprintBefore(a, "m", "k") != FingerprintBefore(b, "m", "k") {
		t.Errorf("no-image variants should hash identically (backward compat)")
	}
}