package anthropic

import (
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"nex/backend/internal/protocol/openai"
)

func TestStreamConverter_MessageStart(t *testing.T) {
	converter := NewStreamConverter("msg_123", "claude-3-opus")

	chunk := &openai.StreamChunk{
		ID:      "chatcmpl-123",
		Choices: []openai.StreamChoice{{Index: 0, Delta: openai.Delta{}}},
	}

	events, err := converter.ConvertChunk(chunk)
	require.NoError(t, err)
	require.NotEmpty(t, events)

	// 第一个事件应该是 message_start
	assert.Equal(t, "message_start", events[0].Type)
	require.NotNil(t, events[0].Message)
	assert.Equal(t, "msg_123", events[0].Message.ID)
	assert.Equal(t, "message", events[0].Message.Type)
	assert.Equal(t, "assistant", events[0].Message.Role)
	assert.Equal(t, "claude-3-opus", events[0].Message.Model)
}

func TestStreamConverter_TextDelta(t *testing.T) {
	converter := NewStreamConverter("msg_123", "claude-3-opus")

	// 先发送一个空块以触发 message_start
	chunk1 := &openai.StreamChunk{
		Choices: []openai.StreamChoice{
			{Delta: openai.Delta{Content: "Hello"}},
		},
	}
	events1, err := converter.ConvertChunk(chunk1)
	require.NoError(t, err)
	// 应有 message_start + content_block_start + text delta
	assert.GreaterOrEqual(t, len(events1), 3)

	// 第二个文本块不应再发送 message_start 和 content_block_start
	chunk2 := &openai.StreamChunk{
		Choices: []openai.StreamChoice{
			{Delta: openai.Delta{Content: " world"}},
		},
	}
	events2, err := converter.ConvertChunk(chunk2)
	require.NoError(t, err)
	// 只有 text delta
	assert.Len(t, events2, 1)
	assert.Equal(t, "content_block_delta", events2[0].Type)
	assert.Equal(t, "text_delta", events2[0].Delta.Type)
	assert.Equal(t, " world", events2[0].Delta.Text)
}

func TestStreamConverter_FinishReason(t *testing.T) {
	converter := NewStreamConverter("msg_123", "claude-3-opus")

	chunk := &openai.StreamChunk{
		Choices: []openai.StreamChoice{
			{Delta: openai.Delta{Content: "Hello"}, FinishReason: "stop"},
		},
	}
	events, err := converter.ConvertChunk(chunk)
	require.NoError(t, err)

	// 查找 message_delta 事件
	var messageDelta *StreamEvent
	for _, e := range events {
		if e.Type == "message_delta" {
			messageDelta = &e
			break
		}
	}
	require.NotNil(t, messageDelta)
	assert.Equal(t, "end_turn", messageDelta.Delta.StopReason)

	// 查找 message_stop 事件
	var messageStop *StreamEvent
	for _, e := range events {
		if e.Type == "message_stop" {
			messageStop = &e
			break
		}
	}
	assert.NotNil(t, messageStop)
}

func TestStreamConverter_FinishReasonToolCalls(t *testing.T) {
	converter := NewStreamConverter("msg_123", "claude-3-opus")

	chunk := &openai.StreamChunk{
		Choices: []openai.StreamChoice{
			{Delta: openai.Delta{}, FinishReason: "tool_calls"},
		},
	}
	events, err := converter.ConvertChunk(chunk)
	require.NoError(t, err)

	var messageDelta *StreamEvent
	for _, e := range events {
		if e.Type == "message_delta" {
			messageDelta = &e
			break
		}
	}
	require.NotNil(t, messageDelta)
	assert.Equal(t, "tool_use", messageDelta.Delta.StopReason)
}

func TestStreamConverter_FinishReasonLength(t *testing.T) {
	converter := NewStreamConverter("msg_123", "claude-3-opus")

	chunk := &openai.StreamChunk{
		Choices: []openai.StreamChoice{
			{Delta: openai.Delta{}, FinishReason: "length"},
		},
	}
	events, err := converter.ConvertChunk(chunk)
	require.NoError(t, err)

	var messageDelta *StreamEvent
	for _, e := range events {
		if e.Type == "message_delta" {
			messageDelta = &e
			break
		}
	}
	require.NotNil(t, messageDelta)
	assert.Equal(t, "max_tokens", messageDelta.Delta.StopReason)
}

func TestStreamConverter_ToolCalls(t *testing.T) {
	converter := NewStreamConverter("msg_123", "claude-3-opus")

	chunk := &openai.StreamChunk{
		Choices: []openai.StreamChoice{
			{
				Delta: openai.Delta{
					ToolCalls: []openai.ToolCall{
						{
							ID:   "call_123",
							Type: "function",
							Function: openai.FunctionCall{
								Name:      "get_weather",
								Arguments: `{"city": "Beijing"}`,
							},
						},
					},
				},
			},
		},
	}

	events, err := converter.ConvertChunk(chunk)
	require.NoError(t, err)

	// 应包含 content_block_start (tool_use) + content_block_delta (input_json_delta)
	hasBlockStart := false
	hasInputDelta := false
	for _, e := range events {
		if e.Type == "content_block_start" && e.ContentBlock != nil && e.ContentBlock.Type == "tool_use" {
			hasBlockStart = true
			assert.Equal(t, "call_123", e.ContentBlock.ID)
			assert.Equal(t, "get_weather", e.ContentBlock.Name)
		}
		if e.Type == "content_block_delta" && e.Delta != nil && e.Delta.Type == "input_json_delta" {
			hasInputDelta = true
			assert.Equal(t, `{"city": "Beijing"}`, e.Delta.Input)
		}
	}
	assert.True(t, hasBlockStart, "应有 tool_use content_block_start")
	assert.True(t, hasInputDelta, "应有 input_json_delta")
}

func TestSerializeEvent(t *testing.T) {
	event := StreamEvent{
		Type: "message_start",
		Message: &MessagesResponse{
			ID:   "msg_123",
			Type: "message",
			Role: "assistant",
		},
	}

	result, err := SerializeEvent(event)
	require.NoError(t, err)
	assert.Contains(t, result, "event: message_start")
	assert.Contains(t, result, "data: ")
	assert.Contains(t, result, "msg_123")
}

func TestSerializeEvent_InvalidJSON(t *testing.T) {
	event := StreamEvent{
		Type: "test",
	}
	// 这个应该能正常序列化
	result, err := SerializeEvent(event)
	require.NoError(t, err)
	assert.Contains(t, result, "event: test")
}

func TestContentBlock_ParseInputJSON(t *testing.T) {
	t.Run("字符串输入", func(t *testing.T) {
		cb := &ContentBlock{Input: `{"key": "value"}`}
		result, err := cb.ParseInputJSON()
		require.NoError(t, err)
		assert.Equal(t, "value", result["key"])
	})

	t.Run("对象输入", func(t *testing.T) {
		cb := &ContentBlock{Input: map[string]interface{}{"key": "value"}}
		result, err := cb.ParseInputJSON()
		require.NoError(t, err)
		assert.Equal(t, "value", result["key"])
	})

	t.Run("无效类型", func(t *testing.T) {
		cb := &ContentBlock{Input: 42}
		_, err := cb.ParseInputJSON()
		assert.Error(t, err)
	})
}