package documentinit

import (
	"bytes"
	"errors"
	"fmt"
	"testing"
	"time"

	"queryorchestration/internal/database/repository"
	"queryorchestration/internal/document"
	"queryorchestration/internal/serviceconfig/objectstore"
	"queryorchestration/internal/test"
	objectstoremock "queryorchestration/mocks/objectstore"
	queuemock "queryorchestration/mocks/queue"

	"github.com/stretchr/testify/require"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/s3"
	"github.com/aws/aws-sdk-go-v2/service/sqs"
	"github.com/google/uuid"
	"github.com/pashagolub/pgxmock/v3"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/mock"
)

func TestCreate(t *testing.T) {
	ctx := t.Context()

	pool, err := pgxmock.NewPool()
	require.NoError(t, err)
	cfg := &DocInitConfig{}
	cfg.DBPool = pool
	cfg.DBQueries = repository.New(pool)
	mockSQS := queuemock.NewMockSQSClient(t)
	cfg.QueueClient = mockSQS

	// Set up mock S3 client for file size measurement
	mockS3 := objectstoremock.NewMockS3Client(t)
	cfg.StoreClient = mockS3

	cfg.DocumentSyncURL = "/i/am/here"

	svc := New(cfg)

	clientId := "hi"
	doc := document.DocumentSummary{
		ID:       uuid.New(),
		ClientID: clientId,
		Hash:     "example_hash",
	}
	bucket := "example_bucket"
	key := objectstore.BucketKey{
		ClientID:  doc.ClientID,
		CreatedAt: time.Now().UTC(),
		EntityID:  uuid.New(),
		Location:  objectstore.Import,
	}

	// Mock HeadObject to return file size
	fileSize := int64(1024)
	mockS3.EXPECT().
		HeadObject(mock.Anything, mock.MatchedBy(func(in *s3.HeadObjectInput) bool {
			return *in.Bucket == bucket && *in.Key == key.String()
		})).
		Return(&s3.HeadObjectOutput{ContentLength: &fileSize}, nil)

	pool.ExpectQuery("name: GetDocumentIDByHash :one").WithArgs(doc.Hash, doc.ClientID).WillReturnRows(
		pgxmock.NewRows([]string{"id"}),
	)
	pool.ExpectBegin()
	pool.ExpectQuery("name: CreateDocument :one").WithArgs(doc.ClientID, doc.Hash, (*uuid.UUID)(nil), (*string)(nil), (*uuid.UUID)(nil), (*string)(nil), &fileSize).
		WillReturnRows(
			pgxmock.NewRows([]string{"id"}).
				AddRow(doc.ID),
		)
	pool.ExpectExec("name: AddDocumentEntry :exec").WithArgs(doc.ID, bucket, key.String()).
		WillReturnResult(pgxmock.NewResult("", 1))
	pool.ExpectCommit()
	pool.ExpectQuery("name: GetDocumentSummary :one").WithArgs(doc.ID).
		WillReturnRows(
			pgxmock.NewRows([]string{"id", "clientId", "hash"}).
				AddRow(doc.ID, doc.ClientID, doc.Hash),
		)
	pool.ExpectQuery("name: GetClient :one").WithArgs(clientId).WillReturnRows(
		pgxmock.NewRows([]string{"id", "clientId", "canSync"}).
			AddRow(clientId, clientId, true),
	)
	pool.ExpectQuery("name: GetClient :one").WithArgs(clientId).WillReturnRows(
		pgxmock.NewRows([]string{"id", "name", "canSync"}).
			AddRow(clientId, "client_name", true),
	)

	mockSQS.EXPECT().
		SendMessage(
			mock.Anything,
			mock.MatchedBy(func(in *sqs.SendMessageInput) bool {
				return *in.QueueUrl == cfg.DocumentSyncURL && *in.MessageBody == fmt.Sprintf("{\"id\":\"%s\"}", doc.ID.String())
			}),
			mock.Anything,
		).
		Return(&sqs.SendMessageOutput{}, nil)

	id, err := svc.Create(ctx, &Create{
		Hash:     doc.Hash,
		Key:      key,
		Bucket:   bucket,
		Filename: nil, // No filename for this test
	})
	require.NoError(t, err)
	assert.Equal(t, doc.ID, id)
}

func TestGetCreateParams(t *testing.T) {
	ctx := t.Context()

	pool, err := pgxmock.NewPool()
	require.NoError(t, err)
	cfg := &DocInitConfig{}
	cfg.DBPool = pool
	cfg.DBQueries = repository.New(pool)

	svc := New(cfg)

	doc := document.DocumentSummary{
		ClientID: "hello",
		Hash:     "example_hash",
	}
	bucket := "example_bucket"
	key := objectstore.BucketKey{
		ClientID:  doc.ClientID,
		CreatedAt: time.Now().UTC(),
		EntityID:  uuid.New(),
		Location:  objectstore.Import,
	}

	pool.ExpectQuery("name: GetDocumentIDByHash :one").WithArgs(doc.Hash, doc.ClientID).WillReturnRows(
		pgxmock.NewRows([]string{"id"}),
	)

	params, err := svc.getCreateParams(ctx, &Create{
		Hash:   doc.Hash,
		Bucket: bucket,
		Key:    key,
	})
	require.NoError(t, err)
	assert.Equal(t, &createDocumentParams{
		Hash:   doc.Hash,
		Bucket: bucket,
		Key:    key,
	}, params)
}

func TestGetCreateParamsExisting(t *testing.T) {
	ctx := t.Context()

	pool, err := pgxmock.NewPool()
	require.NoError(t, err)
	cfg := &DocInitConfig{}
	cfg.DBPool = pool
	cfg.DBQueries = repository.New(pool)

	svc := New(cfg)

	doc := document.DocumentSummary{
		ID:       uuid.New(),
		ClientID: "hello",
		Hash:     "example_hash",
	}
	bucket := "example_bucket"
	key := objectstore.BucketKey{
		ClientID:  doc.ClientID,
		CreatedAt: time.Now().UTC(),
		EntityID:  uuid.New(),
		Location:  objectstore.Import,
	}

	pool.ExpectQuery("name: GetDocumentIDByHash :one").WithArgs(doc.Hash, doc.ClientID).WillReturnRows(
		pgxmock.NewRows([]string{"id"}).
			AddRow(doc.ID),
	)

	params, err := svc.getCreateParams(ctx, &Create{
		Bucket: bucket,
		Key:    key,
		Hash:   doc.Hash,
	})
	require.NoError(t, err)
	dbid := doc.ID
	assert.Equal(t, &createDocumentParams{
		ID:     &dbid,
		Hash:   doc.Hash,
		Bucket: bucket,
		Key:    key,
	}, params)
}

func TestGetCreateParamsCurrentDocErr(t *testing.T) {
	ctx := t.Context()

	pool, err := pgxmock.NewPool()
	require.NoError(t, err)
	cfg := &DocInitConfig{}
	cfg.DBPool = pool
	cfg.DBQueries = repository.New(pool)

	svc := New(cfg)

	doc := document.DocumentSummary{
		ClientID: "hello",
		Hash:     "example_hash",
	}
	bucket := "example_bucket"
	key := objectstore.BucketKey{
		ClientID:  doc.ClientID,
		CreatedAt: time.Now().UTC(),
		EntityID:  uuid.New(),
		Location:  objectstore.Import,
	}

	pool.ExpectQuery("name: GetDocumentIDByHash :one").WithArgs(doc.Hash, doc.ClientID).
		WillReturnError(errors.New("db err"))

	_, err = svc.getCreateParams(ctx, &Create{
		Bucket: bucket,
		Key:    key,
	})
	assert.Error(t, err)
}

func TestSubmitCreate(t *testing.T) {
	ctx := t.Context()

	pool, err := pgxmock.NewPool()
	require.NoError(t, err)
	cfg := &DocInitConfig{}
	cfg.DBPool = pool
	cfg.DBQueries = repository.New(pool)

	// Set up mock S3 client for file size measurement
	mockS3 := objectstoremock.NewMockS3Client(t)
	cfg.StoreClient = mockS3

	svc := New(cfg)

	doc := document.DocumentSummary{
		ID:       uuid.New(),
		ClientID: "hello",
		Hash:     "example_hash",
	}
	bucket := "example_bucket"
	key := objectstore.BucketKey{
		ClientID:  doc.ClientID,
		CreatedAt: time.Now().UTC(),
		EntityID:  uuid.New(),
		Location:  objectstore.Import,
	}

	// Mock HeadObject to return file size
	fileSize := int64(2048)
	mockS3.EXPECT().
		HeadObject(mock.Anything, mock.MatchedBy(func(in *s3.HeadObjectInput) bool {
			return *in.Bucket == bucket && *in.Key == key.String()
		})).
		Return(&s3.HeadObjectOutput{ContentLength: &fileSize}, nil)

	pool.ExpectBegin()
	pool.ExpectQuery("name: CreateDocument :one").WithArgs(doc.ClientID, doc.Hash, (*uuid.UUID)(nil), (*string)(nil), (*uuid.UUID)(nil), (*string)(nil), &fileSize).
		WillReturnRows(
			pgxmock.NewRows([]string{"id"}).
				AddRow(doc.ID),
		)
	pool.ExpectExec("name: AddDocumentEntry :exec").WithArgs(doc.ID, bucket, key.String()).
		WillReturnResult(pgxmock.NewResult("", 1))
	pool.ExpectCommit()

	id, err := svc.submitCreate(ctx, &createDocumentParams{
		Hash:     doc.Hash,
		Bucket:   bucket,
		Key:      key,
		Filename: nil, // No filename for this test
	})
	require.NoError(t, err)
	assert.Equal(t, doc.ID, id)
}

func TestSubmitCreateExists(t *testing.T) {
	ctx := t.Context()

	pool, err := pgxmock.NewPool()
	require.NoError(t, err)
	cfg := &DocInitConfig{}
	cfg.DBPool = pool
	cfg.DBQueries = repository.New(pool)

	// Set up mock S3 client for file size measurement
	mockS3 := objectstoremock.NewMockS3Client(t)
	cfg.StoreClient = mockS3

	svc := New(cfg)

	doc := document.DocumentSummary{
		ID:       uuid.New(),
		ClientID: "hello",
		Hash:     "example_hash",
	}
	bucket := "example_bucket"
	key := objectstore.BucketKey{
		ClientID:  doc.ClientID,
		CreatedAt: time.Now().UTC(),
		EntityID:  uuid.New(),
		Location:  objectstore.Import,
	}

	// Mock HeadObject to return file size (still called even for existing docs)
	fileSize := int64(4096)
	mockS3.EXPECT().
		HeadObject(mock.Anything, mock.MatchedBy(func(in *s3.HeadObjectInput) bool {
			return *in.Bucket == bucket && *in.Key == key.String()
		})).
		Return(&s3.HeadObjectOutput{ContentLength: &fileSize}, nil)

	pool.ExpectBegin()
	pool.ExpectExec("name: AddDocumentEntry :exec").WithArgs(doc.ID, bucket, key.String()).
		WillReturnResult(pgxmock.NewResult("", 1))
	pool.ExpectCommit()

	docid := doc.ID
	id, err := svc.submitCreate(ctx, &createDocumentParams{
		ID:     &docid,
		Hash:   doc.Hash,
		Bucket: bucket,
		Key:    key,
	})
	require.NoError(t, err)
	assert.Equal(t, doc.ID, id)
}

// TestSubmitCreate_HeadObjectError verifies that HeadObject errors are properly propagated.
func TestSubmitCreate_HeadObjectError(t *testing.T) {
	ctx := t.Context()

	pool, err := pgxmock.NewPool()
	require.NoError(t, err)
	cfg := &DocInitConfig{}
	cfg.DBPool = pool
	cfg.DBQueries = repository.New(pool)

	// Set up mock S3 client that returns an error
	mockS3 := objectstoremock.NewMockS3Client(t)
	cfg.StoreClient = mockS3

	svc := New(cfg)

	doc := document.DocumentSummary{
		ID:       uuid.New(),
		ClientID: "hello",
		Hash:     "example_hash",
	}
	bucket := "example_bucket"
	key := objectstore.BucketKey{
		ClientID:  doc.ClientID,
		CreatedAt: time.Now().UTC(),
		EntityID:  uuid.New(),
		Location:  objectstore.Import,
	}

	// Mock HeadObject to return an error
	mockS3.EXPECT().
		HeadObject(mock.Anything, mock.Anything).
		Return(nil, errors.New("access denied"))

	_, err = svc.submitCreate(ctx, &createDocumentParams{
		Hash:   doc.Hash,
		Bucket: bucket,
		Key:    key,
	})
	assert.Error(t, err)
	assert.Contains(t, err.Error(), "failed to measure file size")
	assert.Contains(t, err.Error(), "access denied")
}

// TestSubmitCreate_NoS3Client verifies that missing S3 client returns an error.
func TestSubmitCreate_NoS3Client(t *testing.T) {
	ctx := t.Context()

	pool, err := pgxmock.NewPool()
	require.NoError(t, err)
	cfg := &DocInitConfig{}
	cfg.DBPool = pool
	cfg.DBQueries = repository.New(pool)
	// Intentionally not setting StoreClient

	svc := New(cfg)

	doc := document.DocumentSummary{
		ID:       uuid.New(),
		ClientID: "hello",
		Hash:     "example_hash",
	}
	bucket := "example_bucket"
	key := objectstore.BucketKey{
		ClientID:  doc.ClientID,
		CreatedAt: time.Now().UTC(),
		EntityID:  uuid.New(),
		Location:  objectstore.Import,
	}

	_, err = svc.submitCreate(ctx, &createDocumentParams{
		Hash:   doc.Hash,
		Bucket: bucket,
		Key:    key,
	})
	assert.Error(t, err)
	assert.Contains(t, err.Error(), "S3 client not initialized")
}

// TestMeasureFileSize_NilContentLength verifies handling of nil ContentLength.
func TestMeasureFileSize_NilContentLength(t *testing.T) {
	ctx := t.Context()

	pool, err := pgxmock.NewPool()
	require.NoError(t, err)
	cfg := &DocInitConfig{}
	cfg.DBPool = pool
	cfg.DBQueries = repository.New(pool)

	// Set up mock S3 client that returns nil ContentLength
	mockS3 := objectstoremock.NewMockS3Client(t)
	cfg.StoreClient = mockS3

	svc := New(cfg)

	bucket := "example_bucket"
	key := "example_key"

	mockS3.EXPECT().
		HeadObject(mock.Anything, mock.Anything).
		Return(&s3.HeadObjectOutput{ContentLength: nil}, nil)

	_, err = svc.measureFileSize(ctx, bucket, key)
	assert.Error(t, err)
	assert.Contains(t, err.Error(), "nil ContentLength")
}

// TestMeasureFileSize_Integration tests the measureFileSize function using a real
// S3 client (localstack) to verify that HeadObject correctly returns file sizes.
// This is an integration test that requires Docker.
func TestMeasureFileSize_Integration(t *testing.T) {
	ctx := t.Context()

	// Set up AWS container (localstack) and S3 client
	cfg := &DocInitConfig{}
	test.CreateAWSResources(t, cfg)

	svc := New(cfg)

	// Upload a test file with known content
	bucket := cfg.GetBucket()
	testKey := fmt.Sprintf("test/filesize/%s.txt", uuid.New().String())
	testContent := []byte("Hello, World! This is a test file for measuring file size.")
	expectedSize := int64(len(testContent))

	// Upload the test file to S3
	_, err := cfg.GetStoreClient().PutObject(ctx, &s3.PutObjectInput{
		Bucket: aws.String(bucket),
		Key:    aws.String(testKey),
		Body:   bytes.NewReader(testContent),
	})
	require.NoError(t, err, "failed to upload test file to S3")

	// Measure the file size using our function
	measuredSize, err := svc.measureFileSize(ctx, bucket, testKey)
	require.NoError(t, err, "measureFileSize should not return an error")
	require.NotNil(t, measuredSize, "measured size should not be nil")

	// Verify the measured size matches expected
	assert.Equal(t, expectedSize, *measuredSize, "measured file size should match uploaded content size")
}

// TestMeasureFileSize_Integration_LargeFile tests file size measurement for larger files.
func TestMeasureFileSize_Integration_LargeFile(t *testing.T) {
	ctx := t.Context()

	// Set up AWS container (localstack) and S3 client
	cfg := &DocInitConfig{}
	test.CreateAWSResources(t, cfg)

	svc := New(cfg)

	// Upload a larger test file (1MB)
	bucket := cfg.GetBucket()
	testKey := fmt.Sprintf("test/filesize/large/%s.bin", uuid.New().String())
	expectedSize := int64(1024 * 1024) // 1MB
	testContent := make([]byte, expectedSize)
	for i := range testContent {
		testContent[i] = byte(i % 256)
	}

	// Upload the test file to S3
	_, err := cfg.GetStoreClient().PutObject(ctx, &s3.PutObjectInput{
		Bucket: aws.String(bucket),
		Key:    aws.String(testKey),
		Body:   bytes.NewReader(testContent),
	})
	require.NoError(t, err, "failed to upload large test file to S3")

	// Measure the file size using our function
	measuredSize, err := svc.measureFileSize(ctx, bucket, testKey)
	require.NoError(t, err, "measureFileSize should not return an error for large files")
	require.NotNil(t, measuredSize, "measured size should not be nil")

	// Verify the measured size matches expected
	assert.Equal(t, expectedSize, *measuredSize, "measured file size should match 1MB")
}

// TestMeasureFileSize_Integration_NonExistentKey tests error handling for non-existent S3 keys.
func TestMeasureFileSize_Integration_NonExistentKey(t *testing.T) {
	ctx := t.Context()

	// Set up AWS container (localstack) and S3 client
	cfg := &DocInitConfig{}
	test.CreateAWSResources(t, cfg)

	svc := New(cfg)

	bucket := cfg.GetBucket()
	nonExistentKey := fmt.Sprintf("test/nonexistent/%s.txt", uuid.New().String())

	// Try to measure size of non-existent file
	_, err := svc.measureFileSize(ctx, bucket, nonExistentKey)
	assert.Error(t, err, "measureFileSize should return an error for non-existent key")
	assert.Contains(t, err.Error(), "HeadObject failed", "error should indicate HeadObject failure")
}