feat: «Думать» uses a model's own thinking when it has it (OpenAI-compatible reasoning, Anthropic extended thinking) instead of asking it to think in words too; learned per model, the word-thinking prompt kept for models without; without «Думать» such a model is asked not to think

internal/server/ai.go

@@ -39,6 +39,10 @@ const (
 	DefaultAIURL = "https://agentproxy.minomix.ru"
 )
 
+// aiNativeKey is the config key of what was learned of a model: "1" it
+// thinks by itself, "0" it does not, missing - not known yet.
+func aiNativeKey(id string) string { return "ai_native_" + id }
+
 // aiUserKey is the config key of a user's own switch. Missing means on by
 // default; an explicit "0" means the user turned it off.
 func aiUserKey(id int64) string { return "ai_user_" + strconv.FormatInt(id, 10) }
@@ -54,6 +58,10 @@ type aiConfig struct {
 	URL   string `json:"url,omitempty"`
 	Key   string `json:"key,omitempty"`
 	Model string `json:"model,omitempty"`
+
+	// think, for one request: "on" asks for the model's own thinking, "off"
+	// asks it not to think, "" leaves it to the model.
+	think string
 }
 
 // label is the model's name in the chat: its own, else its model or kind.
@@ -168,6 +176,59 @@ func sseData(r io.Reader, fn func(data string) (stop bool, err error)) error {
 	return sc.Err()
 }
 
+// aiHTTPError is a model's answer other than 2xx.
+type aiHTTPError struct {
+	Code int
+	Msg  string
+}
+
+func (e aiHTTPError) Error() string {
+	return fmt.Sprintf("модель ответила %d: %s", e.Code, e.Msg)
+}
+
+// badRequest: the model did not take the request as it was (an option it
+// does not know, say).
+func badRequest(err error) bool {
+	var e aiHTTPError
+	return errors.As(err, &e) && (e.Code == http.StatusBadRequest || e.Code == http.StatusUnprocessableEntity)
+}
+
+// thinkOpen and thinkClose frame a model's own thinking in the answer, as
+// the chat shows thinking (and as a model asked to think in words writes it).
+const (
+	thinkOpen  = "::думаю::\n"
+	thinkClose = "\n::ответ::\n"
+)
+
+// thinkWrap passes on a model's thinking and answer as they come, the
+// thinking framed by thinkOpen and thinkClose.
+type thinkWrap struct {
+	emit  func(string)
+	state int // 0: nothing yet, 1: thinking, 2: answering
+}
+
+func (w *thinkWrap) think(t string) {
+	if t == "" || w.state == 2 {
+		return
+	}
+	if w.state == 0 {
+		w.emit(thinkOpen)
+		w.state = 1
+	}
+	w.emit(t)
+}
+
+func (w *thinkWrap) text(t string) {
+	if t == "" {
+		return
+	}
+	if w.state == 1 {
+		w.emit(thinkClose)
+	}
+	w.state = 2
+	w.emit(t)
+}
+
 func aiPost(ctx context.Context, url string, body any, hdr map[string]string) (*http.Response, error) {
 	b, _ := json.Marshal(body)
 	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(b))
@@ -185,7 +246,7 @@ func aiPost(ctx context.Context, url string, body any, hdr map[string]string) (*
 	if resp.StatusCode/100 != 2 {
 		msg, _ := io.ReadAll(io.LimitReader(resp.Body, 400))
 		resp.Body.Close()
-		return nil, fmt.Errorf("модель ответила %d: %s", resp.StatusCode, strings.TrimSpace(string(msg)))
+		return nil, aiHTTPError{resp.StatusCode, strings.TrimSpace(string(msg))}
 	}
 	return resp, nil
 }
@@ -226,10 +287,21 @@ func aiOpenAI(ctx context.Context, cfg aiConfig, system string, msgs []aiMsg, em
 	if cfg.Key != "" {
 		hdr["Authorization"] = "Bearer " + cfg.Key
 	}
-	resp, err := aiPost(ctx, cfg.URL+"/chat/completions", map[string]any{"model": cfg.Model, "stream": true, "messages": apiMessages}, hdr)
+	// Thinking on or off by the chat template's switch (llama.cpp, vLLM,
+	// Ollama…); a server that does not know it is asked again without.
+	body := map[string]any{"model": cfg.Model, "stream": true, "messages": apiMessages}
+	if cfg.think != "" {
+		body["chat_template_kwargs"] = map[string]any{"enable_thinking": cfg.think == "on"}
+	}
+	resp, err := aiPost(ctx, cfg.URL+"/chat/completions", body, hdr)
+	if err != nil && cfg.think != "" && badRequest(err) {
+		delete(body, "chat_template_kwargs")
+		resp, err = aiPost(ctx, cfg.URL+"/chat/completions", body, hdr)
+	}
 	if err != nil {
 		return err
 	}
+	tw := &thinkWrap{emit: emit}
 	defer resp.Body.Close()
 	return sseData(resp.Body, func(d string) (bool, error) {
 		if d == "[DONE]" {
@@ -238,7 +310,9 @@ func aiOpenAI(ctx context.Context, cfg aiConfig, system string, msgs []aiMsg, em
 		var m struct {
 			Choices []struct {
 				Delta struct {
-					Content string `json:"content"`
+					Content          string `json:"content"`
+					ReasoningContent string `json:"reasoning_content"`
+					Reasoning        string `json:"reasoning"`
 				} `json:"delta"`
 			} `json:"choices"`
 			Error *struct {
@@ -252,9 +326,8 @@ func aiOpenAI(ctx context.Context, cfg aiConfig, system string, msgs []aiMsg, em
 			return true, errors.New(m.Error.Message)
 		}
 		for _, c := range m.Choices {
-			if c.Delta.Content != "" {
-				emit(c.Delta.Content)
-			}
+			tw.think(c.Delta.ReasoningContent + c.Delta.Reasoning)
+			tw.text(c.Delta.Content)
 		}
 		return false, nil
 	})
@@ -280,17 +353,32 @@ func aiAnthropic(ctx context.Context, cfg aiConfig, system string, msgs []aiMsg,
 		}
 		apiMessages = append(apiMessages, map[string]any{"role": m.Role, "content": content})
 	}
-	resp, err := aiPost(ctx, cfg.URL+"/v1/messages", map[string]any{"model": model, "max_tokens": 4096, "system": system, "messages": apiMessages, "stream": true},
-		map[string]string{"x-api-key": cfg.Key, "anthropic-version": "2023-06-01"})
+	body := map[string]any{"model": model, "max_tokens": 4096, "system": system, "messages": apiMessages, "stream": true}
+	hdr := map[string]string{"x-api-key": cfg.Key, "anthropic-version": "2023-06-01"}
+	// Extended thinking, for «Думать»; a model without it is asked again
+	// as it was.
+	if cfg.think == "on" {
+		body["thinking"] = map[string]any{"type": "enabled", "budget_tokens": 4096}
+		body["max_tokens"] = 12288
+	}
+	resp, err := aiPost(ctx, cfg.URL+"/v1/messages", body, hdr)
+	if err != nil && cfg.think == "on" && badRequest(err) {
+		delete(body, "thinking")
+		body["max_tokens"] = 4096
+		resp, err = aiPost(ctx, cfg.URL+"/v1/messages", body, hdr)
+	}
 	if err != nil {
 		return err
 	}
+	tw := &thinkWrap{emit: emit}
 	defer resp.Body.Close()
 	return sseData(resp.Body, func(d string) (bool, error) {
 		var m struct {
 			Type  string `json:"type"`
 			Delta struct {
-				Text string `json:"text"`
+				Type     string `json:"type"`
+				Text     string `json:"text"`
+				Thinking string `json:"thinking"`
 			} `json:"delta"`
 			Error struct {
 				Message string `json:"message"`
@@ -301,7 +389,11 @@ func aiAnthropic(ctx context.Context, cfg aiConfig, system string, msgs []aiMsg,
 		}
 		switch m.Type {
 		case "content_block_delta":
-			emit(m.Delta.Text)
+			if m.Delta.Type == "thinking_delta" {
+				tw.think(m.Delta.Thinking)
+			} else {
+				tw.text(m.Delta.Text)
+			}
 		case "message_stop":
 			return true, nil
 		case "error":
@@ -807,13 +899,35 @@ func (s *Server) handleAIChat(w http.ResponseWriter, r *http.Request) {
 	if in.Search {
 		system += searchPrompt(s.searchConf())
 	}
-	if in.Think {
+	// «Думать»: a model with thinking of its own (OpenAI-compatible or
+	// Anthropic) thinks by itself, once; the others are asked to think in
+	// words. Which it is, is learned from its answers and kept. Without
+	// «Думать» a model that would think anyway is asked not to.
+	native := ""
+	if cfg.Type == "openai" || cfg.Type == "anthropic" {
+		native, _ = s.db.GetConfig(aiNativeKey(cfg.ID))
+	}
+	ownThink := in.Think && (cfg.Type == "openai" || cfg.Type == "anthropic") && native != "0"
+	promptThink := func() {
 		system += aiThink
 		// Models heed the last words most: the reminder goes there too (not
 		// kept with the talk).
 		if n := len(msgs); n > 0 && msgs[n-1].Role == "user" {
 			msgs[n-1].Content += "\n\n(Сначала подумай: первая строка ответа - ::думаю::, дальше рассуждение, потом строка ::ответ:: и сам ответ.)"
 		}
+		if cfg.Type == "openai" {
+			cfg.think = "off"
+		} else {
+			cfg.think = ""
+		}
+	}
+	switch {
+	case ownThink:
+		cfg.think = "on"
+	case in.Think:
+		promptThink()
+	case cfg.Type == "openai":
+		cfg.think = "off"
 	}
 	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
 	w.Header().Set("Cache-Control", "no-store")
@@ -836,7 +950,40 @@ func (s *Server) handleAIChat(w http.ResponseWriter, r *http.Request) {
 			fl.Flush()
 		}
 	}
-	err := aiStream(r.Context(), cfg, system+"\n\n--- Панель сейчас ---\n"+in.Context, msgs, emit)
+	run := func(ctx context.Context, emit func(string)) error {
+		return aiStream(ctx, cfg, system+"\n\n--- Панель сейчас ---\n"+in.Context, msgs, emit)
+	}
+	var err error
+	if ownThink && native == "" {
+		// Not known yet: its first words tell. Thinking - it has its own;
+		// an answer straight away - it has not, and that answer is dropped
+		// unseen for one asked to think in words.
+		ctx, cancel := context.WithCancel(r.Context())
+		first, dropped := true, false
+		err = run(ctx, func(t string) {
+			if dropped || t == "" {
+				return
+			}
+			if first {
+				first = false
+				if t != thinkOpen {
+					dropped = true
+					cancel()
+					return
+				}
+				_ = s.db.SetConfig(aiNativeKey(cfg.ID), "1")
+			}
+			emit(t)
+		})
+		cancel()
+		if dropped {
+			_ = s.db.SetConfig(aiNativeKey(cfg.ID), "0")
+			promptThink()
+			err = run(r.Context(), emit)
+		}
+	} else {
+		err = run(r.Context(), emit)
+	}
 	// The answer is kept whole, thinking too (to show it again); the model
 	// gets it without (aiWindow).
 	ans := aiMsg{Role: "assistant", Content: answer.String()}
@@ -864,6 +1011,9 @@ func (s *Server) aiNameChat(cfg aiConfig, owner, chat int64, question string) {
 		question = string(r[:600])
 	}
 	var b strings.Builder
+	if cfg.Type == "openai" {
+		cfg.think = "off" // a name needs no thinking
+	}
 	err := aiStream(ctx, cfg, "Придумай короткое название чата по первому вопросу пользователя: 2-3 слова, по-русски, "+
 		"без кавычек и точки в конце. Ответь только названием.", []aiMsg{{Role: "user", Content: question}}, func(t string) { b.WriteString(t) })
 	if err != nil {
@@ -999,6 +1149,11 @@ func (s *Server) handleSetAI(w http.ResponseWriter, r *http.Request) {
 	if len(ms) > 0 {
 		b, _ := json.Marshal(ms)
 		_ = s.db.SetConfig(cfgAIModels, string(b))
+		// A model saved may be another one now: whether it thinks by itself
+		// is learned again.
+		for _, m := range ms {
+			_ = s.db.SetConfig(aiNativeKey(m.ID), "")
+		}
 	}
 	// The search engine for «Поиск».
 	eng := r.FormValue("ai_search")

internal/server/aithink_test.go

@@ -0,0 +1,144 @@
+package server
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"sync"
+	"testing"
+)
+
+// openAIChunk is one streamed delta of an OpenAI-compatible server.
+func openAIChunk(field, text string) string {
+	b, _ := json.Marshal(map[string]any{"choices": []any{map[string]any{"delta": map[string]string{field: text}}}})
+	return "data: " + string(b) + "\n\n"
+}
+
+// A model that thinks by itself (llama.cpp, vLLM: reasoning_content) has its
+// thinking shown as the chat's own: between ::думаю:: and ::ответ::.
+func TestAIOpenAINativeReasoning(t *testing.T) {
+	var body map[string]any
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_ = json.NewDecoder(r.Body).Decode(&body)
+		fmt.Fprint(w, openAIChunk("reasoning_content", "17*23")+openAIChunk("reasoning_content", " = 391")+
+			openAIChunk("content", "391")+"data: [DONE]\n\n")
+	}))
+	defer srv.Close()
+	got, err := collect(t, aiConfig{Type: "openai", URL: srv.URL, Model: "m", think: "on"})
+	if err != nil || got != "::думаю::\n17*23 = 391\n::ответ::\n391" {
+		t.Fatalf("got %q, %v", got, err)
+	}
+	kw, _ := body["chat_template_kwargs"].(map[string]any)
+	if kw["enable_thinking"] != true {
+		t.Fatalf("thinking not asked for: %v", body)
+	}
+}
+
+// A server that does not know the thinking switch (400 on it) is asked again
+// without it.
+func TestAIOpenAIRetriesWithoutThinkSwitch(t *testing.T) {
+	var mu sync.Mutex
+	var calls []map[string]any
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var b map[string]any
+		_ = json.NewDecoder(r.Body).Decode(&b)
+		mu.Lock()
+		calls = append(calls, b)
+		mu.Unlock()
+		if _, ok := b["chat_template_kwargs"]; ok {
+			http.Error(w, `{"error":{"message":"Unrecognized request argument supplied: chat_template_kwargs"}}`, 400)
+			return
+		}
+		fmt.Fprint(w, openAIChunk("content", "ok")+"data: [DONE]\n\n")
+	}))
+	defer srv.Close()
+	got, err := collect(t, aiConfig{Type: "openai", URL: srv.URL, Model: "m", think: "off"})
+	if err != nil || got != "ok" || len(calls) != 2 {
+		t.Fatalf("got %q, %v, %d calls", got, err, len(calls))
+	}
+}
+
+// Anthropic: «Думать» turns on extended thinking; its thinking_delta is the
+// thinking shown.
+func TestAIAnthropicThinking(t *testing.T) {
+	var body map[string]any
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_ = json.NewDecoder(r.Body).Decode(&body)
+		fmt.Fprint(w, "data: {\"type\":\"content_block_delta\",\"delta\":{\"type\":\"thinking_delta\",\"thinking\":\"хм\"}}\n\n"+
+			"data: {\"type\":\"content_block_delta\",\"delta\":{\"type\":\"text_delta\",\"text\":\"Да\"}}\n\n"+
+			"data: {\"type\":\"message_stop\"}\n\n")
+	}))
+	defer srv.Close()
+	got, err := collect(t, aiConfig{Type: "anthropic", URL: srv.URL, Key: "k", Model: "m", think: "on"})
+	if err != nil || got != "::думаю::\nхм\n::ответ::\nДа" {
+		t.Fatalf("got %q, %v", got, err)
+	}
+	th, _ := body["thinking"].(map[string]any)
+	if th["type"] != "enabled" || body["max_tokens"].(float64) <= th["budget_tokens"].(float64) {
+		t.Fatalf("thinking not asked for: %v", body)
+	}
+}
+
+// askThink sends one «Думать» question to the chat and gives the answer and
+// the system prompts the model got, in order.
+func askThink(t *testing.T, reply func(system string, body map[string]any) string) (string, []string) {
+	t.Helper()
+	s, c := newTestServer(t)
+	var mu sync.Mutex
+	var systems []string
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var b map[string]any
+		_ = json.NewDecoder(r.Body).Decode(&b)
+		sys := b["messages"].([]any)[0].(map[string]any)["content"].(string)
+		if strings.Contains(fmt.Sprint(b["messages"]), "название чата") || strings.Contains(sys, "название чата") {
+			fmt.Fprint(w, openAIChunk("content", "Чат")+"data: [DONE]\n\n")
+			return
+		}
+		mu.Lock()
+		systems = append(systems, sys)
+		mu.Unlock()
+		fmt.Fprint(w, reply(sys, b)+"data: [DONE]\n\n")
+	}))
+	t.Cleanup(srv.Close)
+	postAIModels(t, s, c, [][7]string{{"", "M", "openai", srv.URL, "m", "", ""}})
+	req := httptest.NewRequest(http.MethodPost, "/api/panel/ai/chat", strings.NewReader(`{"message":"сколько 17*23","context":"x","think":true}`))
+	req.AddCookie(c)
+	w := httptest.NewRecorder()
+	s.Handler().ServeHTTP(w, req)
+	mu.Lock()
+	defer mu.Unlock()
+	return w.Body.String(), append([]string(nil), systems...)
+}
+
+// A model with thinking of its own thinks once, by itself: no "think in
+// words" prompt on top.
+func TestAIChatThinkNative(t *testing.T) {
+	got, systems := askThink(t, func(sys string, b map[string]any) string {
+		return openAIChunk("reasoning_content", "считаю") + openAIChunk("content", "391")
+	})
+	if len(systems) != 1 || strings.Contains(systems[0], "Режим размышления") {
+		t.Fatalf("systems: %q", systems)
+	}
+	if !strings.Contains(got, "::думаю::\nсчитаю\n::ответ::\n391") {
+		t.Fatalf("answer: %q", got)
+	}
+}
+
+// A model without it is asked again with the prompt, its first answer
+// dropped unseen.
+func TestAIChatThinkPromptFallback(t *testing.T) {
+	got, systems := askThink(t, func(sys string, b map[string]any) string {
+		if strings.Contains(sys, "Режим размышления") {
+			return openAIChunk("content", "::думаю::\nсчитаю\n::ответ::\n391")
+		}
+		return openAIChunk("content", "сразу ответ")
+	})
+	if len(systems) != 2 || strings.Contains(systems[0], "Режим размышления") || !strings.Contains(systems[1], "Режим размышления") {
+		t.Fatalf("systems: %q", systems)
+	}
+	if strings.Contains(got, "сразу ответ") || !strings.Contains(got, "::ответ::\n391") {
+		t.Fatalf("answer: %q", got)
+	}
+}