feat: Phase 4 — LLM 集成，PR 描述生成与 AI 代码审查

2026-06-19 19:43:18 +08:00
parent 7ac3a3726b
commit afb270721c
8 changed files with 783 additions and 29 deletions
@@ -0,0 +1,152 @@
+package services
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"io"
+	"strings"
+
+	goopenai "github.com/sashabaranov/go-openai"
+)
+
+// LLMConfig holds LLM API configuration.
+type LLMConfig struct {
+	Endpoint string
+	APIKey   string
+	Model    string
+}
+
+// GetLLMConfig reads LLM settings from the database.
+func GetLLMConfig(db *sql.DB) (LLMConfig, error) {
+	config := LLMConfig{}
+
+	rows, err := db.Query(`SELECT key, value FROM settings WHERE key IN ('llm.endpoint', 'llm.api_key', 'llm.model')`)
+	if err != nil {
+		return config, fmt.Errorf("read settings: %w", err)
+	}
+	defer rows.Close()
+
+	for rows.Next() {
+		var key, value string
+		if rows.Scan(&key, &value) == nil {
+			switch key {
+			case "llm.endpoint":
+				config.Endpoint = value
+			case "llm.api_key":
+				config.APIKey = value
+			case "llm.model":
+				config.Model = value
+			}
+		}
+	}
+
+	if config.APIKey == "" {
+		return config, fmt.Errorf("LLM API key not configured — please set it in the settings page")
+	}
+
+	if config.Model == "" {
+		config.Model = "gpt-4o"
+	}
+
+	return config, nil
+}
+
+// StreamCallback is called for each SSE event during LLM streaming.
+type StreamCallback func(event string, data interface{})
+
+// ChatStream sends a streaming chat completion request to an OpenAI-compatible API.
+// It calls callback with "content" events for each chunk received.
+// Returns the full concatenated response text.
+func ChatStream(config LLMConfig, messages []goopenai.ChatCompletionMessage, callback StreamCallback) (string, error) {
+	clientConfig := goopenai.DefaultConfig(config.APIKey)
+	if config.Endpoint != "" {
+		clientConfig.BaseURL = config.Endpoint
+	}
+	client := goopenai.NewClientWithConfig(clientConfig)
+
+	ctx := context.Background()
+	stream, err := client.CreateChatCompletionStream(ctx, goopenai.ChatCompletionRequest{
+		Model:    config.Model,
+		Messages: messages,
+		Stream:   true,
+	})
+	if err != nil {
+		return "", fmt.Errorf("create stream: %w", err)
+	}
+	defer stream.Close()
+
+	var fullResponse strings.Builder
+	for {
+		response, err := stream.Recv()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return fullResponse.String(), fmt.Errorf("stream recv: %w", err)
+		}
+		if len(response.Choices) > 0 {
+			content := response.Choices[0].Delta.Content
+			if content != "" {
+				fullResponse.WriteString(content)
+				if callback != nil {
+					callback("content", map[string]interface{}{"content": content})
+				}
+			}
+		}
+	}
+
+	return fullResponse.String(), nil
+}
+
+// extractJSON attempts to extract a JSON object or array from a string
+// that may contain markdown code blocks or extra text.
+func extractJSON(s string) string {
+	// Try to find JSON in markdown code block
+	if idx := strings.Index(s, "```json"); idx >= 0 {
+		start := idx + 7
+		if end := strings.Index(s[start:], "```"); end >= 0 {
+			return strings.TrimSpace(s[start : start+end])
+		}
+	}
+	if idx := strings.Index(s, "```"); idx >= 0 {
+		start := idx + 3
+		if nl := strings.Index(s[start:], "\n"); nl >= 0 {
+			start += nl + 1
+		}
+		if end := strings.Index(s[start:], "```"); end >= 0 {
+			return strings.TrimSpace(s[start : start+end])
+		}
+	}
+
+	// Find first { or [
+	startObj := strings.Index(s, "{")
+	startArr := strings.Index(s, "[")
+
+	var start int
+	var endChar byte
+	if startObj >= 0 && (startArr < 0 || startObj < startArr) {
+		start = startObj
+		endChar = '}'
+	} else if startArr >= 0 {
+		start = startArr
+		endChar = ']'
+	} else {
+		return s
+	}
+
+	// Find matching closing bracket
+	depth := 0
+	for i := start; i < len(s); i++ {
+		if s[i] == '{' || s[i] == '[' {
+			depth++
+		} else if s[i] == '}' || s[i] == ']' {
+			depth--
+			if depth == 0 && s[i] == endChar {
+				return s[start : i+1]
+			}
+		}
+	}
+
+	return s[start:]
+}