sync

internal/analysis/client.go

@@ -0,0 +1,133 @@
+package analysis
+
+import (
+	"context"
+	"fmt"
+	"math/rand"
+	"time"
+
+	"github.com/sstent/fitness-tui/internal/circuitbreaker"
+
+	"github.com/go-resty/resty/v2"
+	"github.com/sstent/fitness-tui/internal/config"
+)
+
+// OpenRouterClient handles communication with the OpenRouter API
+// It manages request retries, circuit breaking, and authentication
+type OpenRouterClient struct {
+	client         *resty.Client                  // HTTP client instance
+	config         *config.Config                 // Application configuration
+	circuitBreaker *circuitbreaker.CircuitBreaker // Circuit breaker for API availability
+}
+
+func NewOpenRouterClient(cfg *config.Config) *OpenRouterClient {
+	timeout := cfg.OpenRouter.Timeout
+	if timeout == 0 {
+		// Fallback to 30s if timeout is not set
+		timeout = 30 * time.Second
+	}
+
+	cb := circuitbreaker.New(5, 30*time.Second)
+	return &OpenRouterClient{
+		client: resty.New().
+			SetBaseURL(cfg.OpenRouter.BaseURL).
+			SetTimeout(timeout).
+			SetHeader("Content-Type", "application/json").
+			SetHeader("HTTP-Referer", "https://github.com/sstent/fitness-tui").
+			SetHeader("Authorization", fmt.Sprintf("Bearer %s", cfg.OpenRouter.APIKey)),
+		config:         cfg,
+		circuitBreaker: cb,
+	}
+}
+
+type AnalysisResponse struct {
+	Choices []struct {
+		Message struct {
+			Content string `json:"content"`
+		} `json:"message"`
+	} `json:"choices"`
+}
+
+func (c *OpenRouterClient) AnalyzeActivity(ctx context.Context, params PromptParams) (string, error) {
+	// Generate prompt using the prompts package
+	var err error
+	prompt := GeneratePrompt(params)
+	payload := map[string]interface{}{
+		"model": c.config.OpenRouter.Model,
+		"messages": []map[string]string{
+			{"role": "user", "content": prompt},
+		},
+	}
+
+	var response AnalysisResponse
+	var resp *resty.Response
+
+	// Check circuit breaker state
+	if !c.circuitBreaker.AllowRequest() {
+		return "", fmt.Errorf("API unavailable (circuit breaker open)")
+	}
+
+	// Retry with exponential backoff and jitter
+	maxRetries := 5
+	baseDelay := 500 * time.Millisecond
+	var lastErr error
+
+	for i := 0; i < maxRetries; i++ {
+		// Check if we should abort due to circuit breaker
+		if !c.circuitBreaker.AllowRequest() {
+			return "", fmt.Errorf("API unavailable (circuit breaker open)")
+		}
+		resp, err = c.client.R().
+			SetContext(ctx).
+			SetBody(payload).
+			SetResult(&response).
+			Post("/chat/completions")
+
+		if err == nil && resp.IsSuccess() {
+			break
+		}
+
+		// Handle rate limiting (429)
+		if resp != nil && resp.StatusCode() == 429 {
+			retryAfter := resp.Header().Get("Retry-After")
+			if retryAfter != "" {
+				if delay, err := time.ParseDuration(retryAfter + "s"); err == nil {
+					time.Sleep(delay)
+					continue
+				}
+			}
+		}
+
+		// If context cancelled, break immediately
+		if ctx.Err() != nil {
+			return "", ctx.Err()
+		}
+
+		// Calculate next backoff with jitter
+		delay := baseDelay * time.Duration(1<<uint(i))         // Exponential: 500ms, 1s, 2s, 4s, 8s
+		jitter := time.Duration(rand.Int63n(int64(delay / 2))) // Up to 50% jitter
+		totalDelay := delay + jitter
+
+		// Store last error for final return
+		if err != nil {
+			lastErr = fmt.Errorf("attempt %d: %w", i+1, err)
+		} else {
+			lastErr = fmt.Errorf("attempt %d: API error %s", i+1, resp.Status())
+		}
+
+		time.Sleep(totalDelay)
+	}
+
+	if err != nil || resp.IsError() {
+		c.circuitBreaker.RecordFailure()
+		return "", fmt.Errorf("API request failed: %w", lastErr)
+	}
+
+	c.circuitBreaker.RecordSuccess()
+
+	if len(response.Choices) == 0 || response.Choices[0].Message.Content == "" {
+		return "", fmt.Errorf("empty analysis content in API response")
+	}
+
+	return response.Choices[0].Message.Content, nil
+}