1 files changed, 168 insertions, 0 deletions
diff --git a/internal/llm/openrouter.go b/internal/llm/openrouter.go
new file mode 100644
index 0000000..f03844a
--- /dev/null
+++ b/internal/llm/openrouter.go
@@ -0,0 +1,168 @@
+// Summary: OpenRouter client implementation leveraging OpenAI-compatible helpers with provider-specific headers.
+package llm
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"strings"
+	"time"
+
+	"codeberg.org/snonux/hexai/internal/logging"
+)
+
+type openRouterClient struct {
+	httpClient         *http.Client
+	apiKey             string
+	baseURL            string
+	defaultModel       string
+	chatLogger         logging.ChatLogger
+	defaultTemperature *float64
+}
+
+func newOpenRouter(baseURL, model, apiKey string, defaultTemp *float64) Client {
+	if strings.TrimSpace(baseURL) == "" {
+		baseURL = "https://openrouter.ai/api/v1"
+	}
+	if strings.TrimSpace(model) == "" {
+		model = "openrouter/auto"
+	}
+	return openRouterClient{
+		httpClient:         &http.Client{Timeout: 30 * time.Second},
+		apiKey:             apiKey,
+		baseURL:            baseURL,
+		defaultModel:       model,
+		chatLogger:         logging.NewChatLogger("openrouter"),
+		defaultTemperature: defaultTemp,
+	}
+}
+
+func (c openRouterClient) Chat(ctx context.Context, messages []Message, opts ...RequestOption) (string, error) {
+	if strings.TrimSpace(c.apiKey) == "" {
+		return nilStringErr("missing OpenRouter API key")
+	}
+	o := Options{Model: c.defaultModel}
+	for _, opt := range opts {
+		opt(&o)
+	}
+	if strings.TrimSpace(o.Model) == "" {
+		o.Model = c.defaultModel
+	}
+	start := time.Now()
+	c.logStart(false, o, messages)
+	req := buildOAChatRequest(o, messages, c.defaultTemperature, false, "llm/openrouter ")
+	body, err := json.Marshal(req)
+	if err != nil {
+		c.logf("marshal error: %v", err)
+		return "", err
+	}
+	endpoint := strings.TrimRight(c.baseURL, "/") + "/chat/completions"
+	logging.Logf("llm/openrouter ", "POST %s", endpoint)
+	resp, err := c.doJSON(ctx, endpoint, body)
+	if err != nil {
+		logging.Logf("llm/openrouter ", "%shttp error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
+		return "", err
+	}
+	defer resp.Body.Close()
+	if err := handleOpenAINon2xx(resp, start, "llm/openrouter ", "openrouter"); err != nil {
+		return "", err
+	}
+	out, err := decodeOpenAIChat(resp, start, "llm/openrouter ")
+	if err != nil {
+		return "", err
+	}
+	if len(out.Choices) == 0 {
+		logging.Logf("llm/openrouter ", "%sno choices returned duration=%s%s", logging.AnsiRed, time.Since(start), logging.AnsiBase)
+		return "", errors.New("openrouter: no choices returned")
+	}
+	content := out.Choices[0].Message.Content
+	logging.Logf("llm/openrouter ", "success choice=0 finish=%s size=%d preview=%s%s%s duration=%s", out.Choices[0].FinishReason, len(content), logging.AnsiGreen, logging.PreviewForLog(content), logging.AnsiBase, time.Since(start))
+	return content, nil
+}
+
+func (c openRouterClient) Name() string         { return "openrouter" }
+func (c openRouterClient) DefaultModel() string { return c.defaultModel }
+
+func (c openRouterClient) ChatStream(ctx context.Context, messages []Message, onDelta func(string), opts ...RequestOption) error {
+	if strings.TrimSpace(c.apiKey) == "" {
+		return errors.New("missing OpenRouter API key")
+	}
+	o := Options{Model: c.defaultModel}
+	for _, opt := range opts {
+		opt(&o)
+	}
+	if strings.TrimSpace(o.Model) == "" {
+		o.Model = c.defaultModel
+	}
+	start := time.Now()
+	c.logStart(true, o, messages)
+	req := buildOAChatRequest(o, messages, c.defaultTemperature, true, "llm/openrouter ")
+	body, err := json.Marshal(req)
+	if err != nil {
+		c.logf("marshal error: %v", err)
+		return err
+	}
+	endpoint := strings.TrimRight(c.baseURL, "/") + "/chat/completions"
+	logging.Logf("llm/openrouter ", "POST %s (stream)", endpoint)
+	resp, err := c.doJSONWithAccept(ctx, endpoint, body, "text/event-stream")
+	if err != nil {
+		logging.Logf("llm/openrouter ", "%shttp error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
+		return err
+	}
+	defer resp.Body.Close()
+	if err := handleOpenAINon2xx(resp, start, "llm/openrouter ", "openrouter"); err != nil {
+		return err
+	}
+	if err := parseOpenAIStream(resp, start, onDelta, "llm/openrouter ", "openrouter"); err != nil {
+		return err
+	}
+	logging.Logf("llm/openrouter ", "stream end duration=%s", time.Since(start))
+	return nil
+}
+
+func (c openRouterClient) logf(format string, args ...any) {
+	logging.Logf("llm/openrouter ", format, args...)
+}
+
+func (c openRouterClient) logStart(stream bool, o Options, messages []Message) {
+	logMessages := make([]struct{ Role, Content string }, len(messages))
+	for i, m := range messages {
+		logMessages[i] = struct{ Role, Content string }{m.Role, m.Content}
+	}
+	c.chatLogger.LogStart(stream, o.Model, o.Temperature, o.MaxTokens, o.Stop, logMessages)
+}
+
+func (c openRouterClient) doJSON(ctx context.Context, url string, body []byte) (*http.Response, error) {
+	headers := map[string]string{
+		"Authorization": "Bearer " + c.apiKey,
+		"HTTP-Referer":  "https://github.com/snonux/hexai",
+		"X-Title":       "Hexai",
+	}
+	return c.doJSONWithHeaders(ctx, url, body, headers, "")
+}
+
+func (c openRouterClient) doJSONWithAccept(ctx context.Context, url string, body []byte, accept string) (*http.Response, error) {
+	headers := map[string]string{
+		"Authorization": "Bearer " + c.apiKey,
+		"HTTP-Referer":  "https://github.com/snonux/hexai",
+		"X-Title":       "Hexai",
+	}
+	return c.doJSONWithHeaders(ctx, url, body, headers, accept)
+}
+
+func (c openRouterClient) doJSONWithHeaders(ctx context.Context, url string, body []byte, headers map[string]string, accept string) (*http.Response, error) {
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(body))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	if strings.TrimSpace(accept) != "" {
+		req.Header.Set("Accept", accept)
+	}
+	for k, v := range headers {
+		req.Header.Set(k, v)
+	}
+	return c.httpClient.Do(req)
+}