package sarama

import (
	"bytes"
	"errors"
	"testing"
)

var (
	emptyFetchResponse = []byte{
		0x00, 0x00, 0x00, 0x00,
	}

	oneMessageFetchResponse = []byte{
		0x00, 0x00, 0x00, 0x01,
		0x00, 0x05, 't', 'o', 'p', 'i', 'c',
		0x00, 0x00, 0x00, 0x01,
		0x00, 0x00, 0x00, 0x05,
		0x00, 0x01,
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x10,
		0x00, 0x00, 0x00, 0x1C,
		// messageSet
		0x00, 0x00, 0x00, 0x00, 0x00, 0x55, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x10,
		// message
		0x23, 0x96, 0x4a, 0xf7, // CRC
		0x00,
		0x00,
		0xFF, 0xFF, 0xFF, 0xFF,
		0x00, 0x00, 0x00, 0x02, 0x00, 0xEE,
	}

	overflowMessageFetchResponse = []byte{
		0x00, 0x00, 0x00, 0x01,
		0x00, 0x05, 't', 'o', 'p', 'i', 'c',
		0x00, 0x00, 0x00, 0x01,
		0x00, 0x00, 0x00, 0x05,
		0x00, 0x01,
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x10,
		0x00, 0x00, 0x00, 0x30,
		// messageSet
		0x00, 0x00, 0x00, 0x00, 0x00, 0x55, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x10,
		// message
		0x23, 0x96, 0x4a, 0xf7, // CRC
		0x00,
		0x00,
		0xFF, 0xFF, 0xFF, 0xFF,
		0x00, 0x00, 0x00, 0x02, 0x00, 0xEE,
		// overflow messageSet
		0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
		0x00, 0x00, 0x00, 0xFF,
		// overflow bytes
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	}

	oneRecordFetchResponse = []byte{
		0x00, 0x00, 0x00, 0x00, // ThrottleTime
		0x00, 0x00, 0x00, 0x01, // Number of Topics
		0x00, 0x05, 't', 'o', 'p', 'i', 'c', // Topic
		0x00, 0x00, 0x00, 0x01, // Number of Partitions
		0x00, 0x00, 0x00, 0x05, // Partition
		0x00, 0x01, // Error
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x10, // High Watermark Offset
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x10, // Last Stable Offset
		0x00, 0x00, 0x00, 0x00, // Number of Aborted Transactions
		0x00, 0x00, 0x00, 0x52, // Records length
		// recordBatch
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x46,
		0x00, 0x00, 0x00, 0x00,
		0x02,
		0xDB, 0x47, 0x14, 0xC9,
		0x00, 0x00,
		0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0A,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00,
		0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x01,
		// record
		0x28,
		0x00,
		0x0A,
		0x00,
		0x08, 0x01, 0x02, 0x03, 0x04,
		0x06, 0x05, 0x06, 0x07,
		0x02,
		0x06, 0x08, 0x09, 0x0A,
		0x04, 0x0B, 0x0C,
	}

	partialFetchResponse = []byte{
		0x00, 0x00, 0x00, 0x00, // ThrottleTime
		0x00, 0x00, 0x00, 0x01, // Number of Topics
		0x00, 0x05, 't', 'o', 'p', 'i', 'c', // Topic
		0x00, 0x00, 0x00, 0x01, // Number of Partitions
		0x00, 0x00, 0x00, 0x05, // Partition
		0x00, 0x00, // Error
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x10, // High Watermark Offset
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x10, // Last Stable Offset
		0x00, 0x00, 0x00, 0x00, // Number of Aborted Transactions
		0x00, 0x00, 0x00, 0x40, // Records length

		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x46,
		0x00, 0x00, 0x00, 0x00,
		0x02,
		0xDB, 0x47, 0x14, 0xC9,
		0x00, 0x00,
		0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0A,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00,
		0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x01,
		// record
		0x28,
		0x00,
		0x00,
	}

	emptyRecordsFetchResponsev11 = []byte{
		0x00, 0x00, 0x00, 0x00, // ThrottleTime
		0x00, 0x00, // Error
		0x00, 0x00, 0x00, 0x00, // Fetch session
		0x00, 0x00, 0x00, 0x01, // Num topic
		0x00, 0x05, 't', 'o', 'p', 'i', 'c', // Topic
		0x00, 0x00, 0x00, 0x01, // Num partition
		0x00, 0x00, 0x00, 0x05, // Partition
		0x00, 0x00, // Error
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x10, // High Watermark Offset
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x10, // Last Stable Offset
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Log start offset
		0x00, 0x00, 0x00, 0x00, // Number of Aborted Transactions
		0xff, 0xff, 0xff, 0xff, // Replica id
		0x00, 0x00, 0x00, 0x3D, // Batch size
		// recordBatch
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Offset
		0x00, 0x00, 0x00, 0x31, // Message size
		0x00, 0x00, 0x00, 0x00, // Leader epoch
		0x02,                   // Magic byte
		0x14, 0xE0, 0x7A, 0x62, // CRC
		0x00, 0x00, // Flags
		0x00, 0x00, 0x00, 0x00, // Last offset delta
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0A, // First timestamp
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0B, // Last timestamp
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, // Producer id
		0x00, 0x00, // Producer epoch
		0x00, 0x00, 0x00, 0x3d, // Base sequence
		0x00, 0x00, 0x00, 0x00, // Records size
	}

	oneMessageFetchResponseV4 = []byte{
		0x00, 0x00, 0x00, 0x00, // ThrottleTime
		0x00, 0x00, 0x00, 0x01, // Number of Topics
		0x00, 0x05, 't', 'o', 'p', 'i', 'c', // Topic
		0x00, 0x00, 0x00, 0x01, // Number of Partitions
		0x00, 0x00, 0x00, 0x05, // Partition
		0x00, 0x01, // Error
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x10, // High Watermark Offset
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x10, // Last Stable Offset
		0x00, 0x00, 0x00, 0x00, // Number of Aborted Transactions
		0x00, 0x00, 0x00, 0x1C,
		// messageSet
		0x00, 0x00, 0x00, 0x00, 0x00, 0x55, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x10,
		// message
		0x23, 0x96, 0x4a, 0xf7, // CRC
		0x00,
		0x00,
		0xFF, 0xFF, 0xFF, 0xFF,
		0x00, 0x00, 0x00, 0x02, 0x00, 0xEE,
	}

	preferredReplicaFetchResponseV11 = []byte{
		0x00, 0x00, 0x00, 0x00, // ThrottleTime
		0x00, 0x02, // ErrorCode
		0x00, 0x00, 0x00, 0xAC, // SessionID
		0x00, 0x00, 0x00, 0x01, // Number of Topics
		0x00, 0x05, 't', 'o', 'p', 'i', 'c', // Topic
		0x00, 0x00, 0x00, 0x01, // Number of Partitions
		0x00, 0x00, 0x00, 0x05, // Partition
		0x00, 0x01, // Error
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x10, // High Watermark Offset
		0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x10, 0x09, // Last Stable Offset
		0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01, // Log Start Offset
		0x00, 0x00, 0x00, 0x00, // Number of Aborted Transactions
		0x00, 0x00, 0x00, 0x03, // Preferred Read Replica
		0x00, 0x00, 0x00, 0x1C,
		// messageSet
		0x00, 0x00, 0x00, 0x00, 0x00, 0x55, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x10,
		// message
		0x23, 0x96, 0x4a, 0xf7, // CRC
		0x00,
		0x00,
		0xFF, 0xFF, 0xFF, 0xFF,
		0x00, 0x00, 0x00, 0x02, 0x00, 0xEE,
	}
)

func TestEmptyFetchResponse(t *testing.T) {
	response := FetchResponse{}
	testVersionDecodable(t, "empty", &response, emptyFetchResponse, 0)

	if len(response.Blocks) != 0 {
		t.Error("Decoding produced topic blocks where there were none.")
	}
}

func TestOneMessageFetchResponse(t *testing.T) {
	response := FetchResponse{}
	testVersionDecodable(t, "one message", &response, oneMessageFetchResponse, 0)

	if len(response.Blocks) != 1 {
		t.Fatal("Decoding produced incorrect number of topic blocks.")
	}

	if len(response.Blocks["topic"]) != 1 {
		t.Fatal("Decoding produced incorrect number of partition blocks for topic.")
	}

	block := response.GetBlock("topic", 5)
	if block == nil {
		t.Fatal("GetBlock didn't return block.")
	}
	if !errors.Is(block.Err, ErrOffsetOutOfRange) {
		t.Error("Decoding didn't produce correct error code.")
	}
	if block.HighWaterMarkOffset != 0x10101010 {
		t.Error("Decoding didn't produce correct high water mark offset.")
	}
	if block.PreferredReadReplica != -1 {
		t.Error("Decoding didn't produce correct preferred read replica.")
	}
	partial, err := block.isPartial()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if partial {
		t.Error("Decoding detected a partial trailing message where there wasn't one.")
	}

	n, err := block.numRecords()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if n != 1 {
		t.Fatal("Decoding produced incorrect number of messages.")
	}
	msgBlock := block.RecordsSet[0].MsgSet.Messages[0]
	if msgBlock.Offset != 0x550000 {
		t.Error("Decoding produced incorrect message offset.")
	}
	msg := msgBlock.Msg
	if msg.Codec != CompressionNone {
		t.Error("Decoding produced incorrect message compression.")
	}
	if msg.Key != nil {
		t.Error("Decoding produced message key where there was none.")
	}
	if !bytes.Equal(msg.Value, []byte{0x00, 0xEE}) {
		t.Error("Decoding produced incorrect message value.")
	}
}

func TestOverflowMessageFetchResponse(t *testing.T) {
	response := FetchResponse{}
	testVersionDecodable(t, "overflow message", &response, overflowMessageFetchResponse, 0)

	if len(response.Blocks) != 1 {
		t.Fatal("Decoding produced incorrect number of topic blocks.")
	}

	if len(response.Blocks["topic"]) != 1 {
		t.Fatal("Decoding produced incorrect number of partition blocks for topic.")
	}

	block := response.GetBlock("topic", 5)
	if block == nil {
		t.Fatal("GetBlock didn't return block.")
	}
	if !errors.Is(block.Err, ErrOffsetOutOfRange) {
		t.Error("Decoding didn't produce correct error code.")
	}
	if block.HighWaterMarkOffset != 0x10101010 {
		t.Error("Decoding didn't produce correct high water mark offset.")
	}
	partial, err := block.Records.isPartial()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if partial {
		t.Error("Decoding detected a partial trailing message where there wasn't one.")
	}
	overflow, err := block.Records.isOverflow()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if !overflow {
		t.Error("Decoding detected a partial trailing message where there wasn't one.")
	}

	n, err := block.Records.numRecords()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if n != 1 {
		t.Fatal("Decoding produced incorrect number of messages.")
	}
	msgBlock := block.Records.MsgSet.Messages[0]
	if msgBlock.Offset != 0x550000 {
		t.Error("Decoding produced incorrect message offset.")
	}
	msg := msgBlock.Msg
	if msg.Codec != CompressionNone {
		t.Error("Decoding produced incorrect message compression.")
	}
	if msg.Key != nil {
		t.Error("Decoding produced message key where there was none.")
	}
	if !bytes.Equal(msg.Value, []byte{0x00, 0xEE}) {
		t.Error("Decoding produced incorrect message value.")
	}
}

func TestOneRecordFetchResponse(t *testing.T) {
	response := FetchResponse{}
	testVersionDecodable(t, "one record", &response, oneRecordFetchResponse, 4)

	if len(response.Blocks) != 1 {
		t.Fatal("Decoding produced incorrect number of topic blocks.")
	}

	if len(response.Blocks["topic"]) != 1 {
		t.Fatal("Decoding produced incorrect number of partition blocks for topic.")
	}

	block := response.GetBlock("topic", 5)
	if block == nil {
		t.Fatal("GetBlock didn't return block.")
	}
	if !errors.Is(block.Err, ErrOffsetOutOfRange) {
		t.Error("Decoding didn't produce correct error code.")
	}
	if block.HighWaterMarkOffset != 0x10101010 {
		t.Error("Decoding didn't produce correct high water mark offset.")
	}
	if block.PreferredReadReplica != -1 {
		t.Error("Decoding didn't produce correct preferred read replica.")
	}
	partial, err := block.isPartial()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if partial {
		t.Error("Decoding detected a partial trailing record where there wasn't one.")
	}

	n, err := block.numRecords()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if n != 1 {
		t.Fatal("Decoding produced incorrect number of records.")
	}
	rec := block.RecordsSet[0].RecordBatch.Records[0]
	if !bytes.Equal(rec.Key, []byte{0x01, 0x02, 0x03, 0x04}) {
		t.Error("Decoding produced incorrect record key.")
	}
	if !bytes.Equal(rec.Value, []byte{0x05, 0x06, 0x07}) {
		t.Error("Decoding produced incorrect record value.")
	}
}

func TestPartailFetchResponse(t *testing.T) {
	response := FetchResponse{}
	testVersionDecodable(t, "partial record", &response, partialFetchResponse, 4)

	if len(response.Blocks) != 1 {
		t.Fatal("Decoding produced incorrect number of topic blocks.")
	}

	if len(response.Blocks["topic"]) != 1 {
		t.Fatal("Decoding produced incorrect number of partition blocks for topic.")
	}

	block := response.GetBlock("topic", 5)
	if block == nil {
		t.Fatal("GetBlock didn't return block.")
	}
	if !errors.Is(block.Err, ErrNoError) {
		t.Error("Decoding didn't produce correct error code.")
	}
	if block.HighWaterMarkOffset != 0x10101010 {
		t.Error("Decoding didn't produce correct high water mark offset.")
	}
	if block.PreferredReadReplica != -1 {
		t.Error("Decoding didn't produce correct preferred read replica.")
	}
	partial, err := block.isPartial()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if !partial {
		t.Error("Decoding not a partial trailing record")
	}

	n, err := block.numRecords()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if n != 0 {
		t.Fatal("Decoding produced incorrect number of records.")
	}
}

func TestEmptyRecordsFetchResponse(t *testing.T) {
	response := FetchResponse{}
	testVersionDecodable(t, "empty record", &response, emptyRecordsFetchResponsev11, 11)

	if len(response.Blocks) != 1 {
		t.Fatal("Decoding produced incorrect number of topic blocks.")
	}

	if len(response.Blocks["topic"]) != 1 {
		t.Fatal("Decoding produced incorrect number of partition blocks for topic.")
	}

	block := response.GetBlock("topic", 5)
	if block == nil {
		t.Fatal("GetBlock didn't return block.")
	}
	if !errors.Is(block.Err, ErrNoError) {
		t.Error("Decoding didn't produce correct error code.")
	}
	if block.HighWaterMarkOffset != 0x10101010 {
		t.Error("Decoding didn't produce correct high water mark offset.")
	}
	if block.PreferredReadReplica != -1 {
		t.Error("Decoding didn't produce correct preferred read replica.")
	}
	partial, err := block.isPartial()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if partial {
		t.Error("Decoding a partial trailing record")
	}

	n, err := block.numRecords()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if n != 0 {
		t.Fatal("Decoding produced incorrect number of records.")
	}
	if *block.LastRecordsBatchOffset != 0 {
		t.Fatal("Last records batch offset is incorrect.")
	}
}

func TestOneMessageFetchResponseV4(t *testing.T) {
	response := FetchResponse{}
	testVersionDecodable(t, "one message v4", &response, oneMessageFetchResponseV4, 4)

	if len(response.Blocks) != 1 {
		t.Fatal("Decoding produced incorrect number of topic blocks.")
	}

	if len(response.Blocks["topic"]) != 1 {
		t.Fatal("Decoding produced incorrect number of partition blocks for topic.")
	}

	block := response.GetBlock("topic", 5)
	if block == nil {
		t.Fatal("GetBlock didn't return block.")
	}
	if !errors.Is(block.Err, ErrOffsetOutOfRange) {
		t.Error("Decoding didn't produce correct error code.")
	}
	if block.HighWaterMarkOffset != 0x10101010 {
		t.Error("Decoding didn't produce correct high water mark offset.")
	}
	if block.PreferredReadReplica != -1 {
		t.Error("Decoding didn't produce correct preferred read replica.")
	}
	partial, err := block.isPartial()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if partial {
		t.Error("Decoding detected a partial trailing record where there wasn't one.")
	}

	n, err := block.numRecords()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if n != 1 {
		t.Fatal("Decoding produced incorrect number of records.")
	}
	msgBlock := block.RecordsSet[0].MsgSet.Messages[0]
	if msgBlock.Offset != 0x550000 {
		t.Error("Decoding produced incorrect message offset.")
	}
	msg := msgBlock.Msg
	if msg.Codec != CompressionNone {
		t.Error("Decoding produced incorrect message compression.")
	}
	if msg.Key != nil {
		t.Error("Decoding produced message key where there was none.")
	}
	if !bytes.Equal(msg.Value, []byte{0x00, 0xEE}) {
		t.Error("Decoding produced incorrect message value.")
	}
}

func TestPreferredReplicaFetchResponseV11(t *testing.T) {
	response := FetchResponse{}
	testVersionDecodable(
		t, "preferred replica fetch response v11", &response,
		preferredReplicaFetchResponseV11, 11)

	if response.ErrorCode != 0x0002 {
		t.Fatal("Decoding produced incorrect error code.")
	}

	if response.SessionID != 0x000000AC {
		t.Fatal("Decoding produced incorrect session ID.")
	}

	if len(response.Blocks) != 1 {
		t.Fatal("Decoding produced incorrect number of topic blocks.")
	}

	if len(response.Blocks["topic"]) != 1 {
		t.Fatal("Decoding produced incorrect number of partition blocks for topic.")
	}

	block := response.GetBlock("topic", 5)
	if block == nil {
		t.Fatal("GetBlock didn't return block.")
	}
	if !errors.Is(block.Err, ErrOffsetOutOfRange) {
		t.Error("Decoding didn't produce correct error code.")
	}
	if block.HighWaterMarkOffset != 0x10101010 {
		t.Error("Decoding didn't produce correct high water mark offset.")
	}
	if block.LastStableOffset != 0x10101009 {
		t.Error("Decoding didn't produce correct last stable offset.")
	}
	if block.LogStartOffset != 0x01010101 {
		t.Error("Decoding didn't produce correct log start offset.")
	}
	if block.PreferredReadReplica != 0x0003 {
		t.Error("Decoding didn't produce correct preferred read replica.")
	}
	partial, err := block.isPartial()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if partial {
		t.Error("Decoding detected a partial trailing record where there wasn't one.")
	}

	n, err := block.numRecords()
	if err != nil {
		t.Fatalf("Unexpected error: %v", err)
	}
	if n != 1 {
		t.Fatal("Decoding produced incorrect number of records.")
	}
	msgBlock := block.RecordsSet[0].MsgSet.Messages[0]
	if msgBlock.Offset != 0x550000 {
		t.Error("Decoding produced incorrect message offset.")
	}
	msg := msgBlock.Msg
	if msg.Codec != CompressionNone {
		t.Error("Decoding produced incorrect message compression.")
	}
	if msg.Key != nil {
		t.Error("Decoding produced message key where there was none.")
	}
	if !bytes.Equal(msg.Value, []byte{0x00, 0xEE}) {
		t.Error("Decoding produced incorrect message value.")
	}
}
