package database

import (
	"context"
	"strings"
	"testing"
	"time"
)

func TestBlobChunkRepository(t *testing.T) {
	db, cleanup := setupTestDB(t)
	defer cleanup()

	ctx := context.Background()
	repos := NewRepositories(db)

	// Create blob first
	blob := &Blob{
		ID:        "blob1-uuid",
		Hash:      "blob1-hash",
		CreatedTS: time.Now(),
	}
	err := repos.Blobs.Create(ctx, nil, blob)
	if err != nil {
		t.Fatalf("failed to create blob: %v", err)
	}

	// Create chunks
	chunks := []string{"chunk1", "chunk2", "chunk3"}
	for _, chunkHash := range chunks {
		chunk := &Chunk{
			ChunkHash: chunkHash,
			Size:      1024,
		}
		err = repos.Chunks.Create(ctx, nil, chunk)
		if err != nil {
			t.Fatalf("failed to create chunk %s: %v", chunkHash, err)
		}
	}

	// Test Create
	bc1 := &BlobChunk{
		BlobID:    blob.ID,
		ChunkHash: "chunk1",
		Offset:    0,
		Length:    1024,
	}

	err = repos.BlobChunks.Create(ctx, nil, bc1)
	if err != nil {
		t.Fatalf("failed to create blob chunk: %v", err)
	}

	// Add more chunks to the same blob
	bc2 := &BlobChunk{
		BlobID:    blob.ID,
		ChunkHash: "chunk2",
		Offset:    1024,
		Length:    2048,
	}
	err = repos.BlobChunks.Create(ctx, nil, bc2)
	if err != nil {
		t.Fatalf("failed to create second blob chunk: %v", err)
	}

	bc3 := &BlobChunk{
		BlobID:    blob.ID,
		ChunkHash: "chunk3",
		Offset:    3072,
		Length:    512,
	}
	err = repos.BlobChunks.Create(ctx, nil, bc3)
	if err != nil {
		t.Fatalf("failed to create third blob chunk: %v", err)
	}

	// Test GetByBlobID
	blobChunks, err := repos.BlobChunks.GetByBlobID(ctx, blob.ID)
	if err != nil {
		t.Fatalf("failed to get blob chunks: %v", err)
	}
	if len(blobChunks) != 3 {
		t.Errorf("expected 3 chunks, got %d", len(blobChunks))
	}

	// Verify order by offset
	expectedOffsets := []int64{0, 1024, 3072}
	for i, bc := range blobChunks {
		if bc.Offset != expectedOffsets[i] {
			t.Errorf("wrong chunk order: expected offset %d, got %d", expectedOffsets[i], bc.Offset)
		}
	}

	// Test GetByChunkHash
	bc, err := repos.BlobChunks.GetByChunkHash(ctx, "chunk2")
	if err != nil {
		t.Fatalf("failed to get blob chunk by chunk hash: %v", err)
	}
	if bc == nil {
		t.Fatal("expected blob chunk, got nil")
	}
	if bc.BlobID != blob.ID {
		t.Errorf("wrong blob ID: expected %s, got %s", blob.ID, bc.BlobID)
	}
	if bc.Offset != 1024 {
		t.Errorf("wrong offset: expected 1024, got %d", bc.Offset)
	}

	// Test duplicate insert (should fail due to primary key constraint)
	err = repos.BlobChunks.Create(ctx, nil, bc1)
	if err == nil {
		t.Fatal("duplicate blob_chunk insert should fail due to primary key constraint")
	}
	if !strings.Contains(err.Error(), "UNIQUE") && !strings.Contains(err.Error(), "constraint") {
		t.Fatalf("expected constraint error, got: %v", err)
	}

	// Test non-existent chunk
	bc, err = repos.BlobChunks.GetByChunkHash(ctx, "nonexistent")
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if bc != nil {
		t.Error("expected nil for non-existent chunk")
	}
}

func TestBlobChunkRepositoryMultipleBlobs(t *testing.T) {
	db, cleanup := setupTestDB(t)
	defer cleanup()

	ctx := context.Background()
	repos := NewRepositories(db)

	// Create blobs
	blob1 := &Blob{
		ID:        "blob1-uuid",
		Hash:      "blob1-hash",
		CreatedTS: time.Now(),
	}
	blob2 := &Blob{
		ID:        "blob2-uuid",
		Hash:      "blob2-hash",
		CreatedTS: time.Now(),
	}

	err := repos.Blobs.Create(ctx, nil, blob1)
	if err != nil {
		t.Fatalf("failed to create blob1: %v", err)
	}
	err = repos.Blobs.Create(ctx, nil, blob2)
	if err != nil {
		t.Fatalf("failed to create blob2: %v", err)
	}

	// Create chunks
	chunkHashes := []string{"chunk1", "chunk2", "chunk3"}
	for _, chunkHash := range chunkHashes {
		chunk := &Chunk{
			ChunkHash: chunkHash,
			Size:      1024,
		}
		err = repos.Chunks.Create(ctx, nil, chunk)
		if err != nil {
			t.Fatalf("failed to create chunk %s: %v", chunkHash, err)
		}
	}

	// Create chunks across multiple blobs
	// Some chunks are shared between blobs (deduplication scenario)
	blobChunks := []BlobChunk{
		{BlobID: blob1.ID, ChunkHash: "chunk1", Offset: 0, Length: 1024},
		{BlobID: blob1.ID, ChunkHash: "chunk2", Offset: 1024, Length: 1024},
		{BlobID: blob2.ID, ChunkHash: "chunk2", Offset: 0, Length: 1024}, // chunk2 is shared
		{BlobID: blob2.ID, ChunkHash: "chunk3", Offset: 1024, Length: 1024},
	}

	for _, bc := range blobChunks {
		err := repos.BlobChunks.Create(ctx, nil, &bc)
		if err != nil {
			t.Fatalf("failed to create blob chunk: %v", err)
		}
	}

	// Verify blob1 chunks
	chunks, err := repos.BlobChunks.GetByBlobID(ctx, blob1.ID)
	if err != nil {
		t.Fatalf("failed to get blob1 chunks: %v", err)
	}
	if len(chunks) != 2 {
		t.Errorf("expected 2 chunks for blob1, got %d", len(chunks))
	}

	// Verify blob2 chunks
	chunks, err = repos.BlobChunks.GetByBlobID(ctx, blob2.ID)
	if err != nil {
		t.Fatalf("failed to get blob2 chunks: %v", err)
	}
	if len(chunks) != 2 {
		t.Errorf("expected 2 chunks for blob2, got %d", len(chunks))
	}

	// Verify shared chunk
	bc, err := repos.BlobChunks.GetByChunkHash(ctx, "chunk2")
	if err != nil {
		t.Fatalf("failed to get shared chunk: %v", err)
	}
	if bc == nil {
		t.Fatal("expected shared chunk, got nil")
	}
	// GetByChunkHash returns first match, should be blob1
	if bc.BlobID != blob1.ID {
		t.Errorf("expected %s for shared chunk, got %s", blob1.ID, bc.BlobID)
	}
}