package model

import (
	"context"
	"net/http"
	"strings"
	"testing"

	"git.yeij.top/AskaEth/Cyrene_v2/internal/config"
)

// newDeepSeekAdapter builds an OpenAI-compatible adapter pointed at a stub server
// but classified as DeepSeek by its model name, so the DeepSeek mapping is
// exercised against the real request body.
func newDeepSeekAdapter(t *testing.T, ch chan<- capturedRequest, opts ...OpenAIOption) *OpenAIChatAdapter {
	t.Helper()
	srv := newCompletionServer(t, http.StatusOK, "application/json", okCompletion, ch)
	return NewOpenAIChat(config.LLMConfig{BaseURL: srv.URL, Model: deepSeekModel}, opts...)
}

// deepSeekModel is the current DeepSeek model name (the old deepseek-chat /
// deepseek-reasoner names were discontinued on 2026-07-24).
const deepSeekModel = "deepseek-flash"

// deepSeekThinkingType reads body.thinking.type, reporting whether the switch was
// sent at all.
func deepSeekThinkingType(body map[string]any) (string, bool) {
	block, ok := body["thinking"].(map[string]any)
	if !ok {
		return "", false
	}
	value, _ := block["type"].(string)
	return value, true
}

// TestOpenAIChat_DeepSeekReasoningEffortMatrix pins the official value set end to
// end at the request body: none/low/high/max pass through untouched and the four
// compatibility aliases are normalized to the tier DeepSeek applies
// (minimal→low, medium/xhigh→high, ultra→max). The old behavior — grading "none"
// down to "low" — turned thinking off into thinking on, so "none" must arrive as
// "none".
func TestOpenAIChat_DeepSeekReasoningEffortMatrix(t *testing.T) {
	t.Parallel()
	cases := []struct{ sent, want string }{
		{"none", "none"},
		{"low", "low"},
		{"high", "high"},
		{"max", "max"},
		{"minimal", "low"},
		{"medium", "high"},
		{"xhigh", "high"},
		{"ultra", "max"},
	}
	for _, tc := range cases {
		t.Run(tc.sent, func(t *testing.T) {
			t.Parallel()
			ch := make(chan capturedRequest, 1)
			ad := newDeepSeekAdapter(t, ch)
			if _, err := ad.Chat(context.Background(), Request{
				Model:           deepSeekModel,
				Messages:        []Message{TextMessage(RoleUser, "hi")},
				ReasoningEffort: tc.sent,
			}, Options{}); err != nil {
				t.Fatalf("Chat error: %v", err)
			}
			body := (<-ch).body
			if got := body["reasoning_effort"]; got != tc.want {
				t.Fatalf("body.reasoning_effort = %v, want %q (sent %q)", got, tc.want, tc.sent)
			}
			if _, present := body["thinking"]; present {
				t.Errorf("body.thinking = %v, want no switch invented from an effort", body["thinking"])
			}
		})
	}
}

// TestOpenAIChat_DeepSeekReasoningEffortInvalidDropped asserts an unrecognized
// value is dropped and reported — never replaced by a nearby tier, which is how
// the original "round down" logic inverted the caller's intent.
func TestOpenAIChat_DeepSeekReasoningEffortInvalidDropped(t *testing.T) {
	t.Parallel()
	ch := make(chan capturedRequest, 1)
	log, buf := captureLog()
	ad := newDeepSeekAdapter(t, ch, WithOpenAILogger(log))

	if _, err := ad.Chat(context.Background(), Request{
		Model:           deepSeekModel,
		Messages:        []Message{TextMessage(RoleUser, "hi")},
		ReasoningEffort: "foo",
	}, Options{}); err != nil {
		t.Fatalf("Chat error: %v", err)
	}
	body := (<-ch).body
	if _, present := body["reasoning_effort"]; present {
		t.Fatalf("body.reasoning_effort = %v, want the field dropped", body["reasoning_effort"])
	}
	if _, present := body["thinking"]; present {
		t.Fatalf("body.thinking = %v, want no switch invented", body["thinking"])
	}
	rec := buf.String()
	for _, want := range []string{"level=WARN", "reasoning_effort", "foo", deepSeekModel, "deepseek"} {
		if !strings.Contains(rec, want) {
			t.Errorf("log %q missing %q", rec, want)
		}
	}
}

// TestOpenAIChat_DeepSeekThinkingSwitch asserts the DeepSeek thinking switch is
// really sent: an explicit off must reach the wire (DeepSeek defaults to enabled,
// so staying silent would leave thinking ON), and nil must not be turned into
// either value.
func TestOpenAIChat_DeepSeekThinkingSwitch(t *testing.T) {
	t.Parallel()
	cases := []struct {
		name       string
		enable     *bool
		wantType   string
		wantAbsent bool
	}{
		{name: "explicit_off", enable: boolPtr(false), wantType: thinkingTypeDisabled},
		{name: "explicit_on", enable: boolPtr(true), wantType: thinkingTypeEnabled},
		{name: "nil_leaves_the_default", enable: nil, wantAbsent: true},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()
			ch := make(chan capturedRequest, 1)
			ad := newDeepSeekAdapter(t, ch)
			req := Request{Model: deepSeekModel, Messages: []Message{TextMessage(RoleUser, "hi")}}
			if tc.enable != nil {
				req.Thinking = &Thinking{Enable: tc.enable}
			}
			if _, err := ad.Chat(context.Background(), req, Options{}); err != nil {
				t.Fatalf("Chat error: %v", err)
			}
			got, present := deepSeekThinkingType((<-ch).body)
			if tc.wantAbsent {
				if present {
					t.Fatalf("body.thinking.type = %q, want the field omitted (not equal to off)", got)
				}
				return
			}
			if !present || got != tc.wantType {
				t.Fatalf("body.thinking.type = %q (present=%v), want %q", got, present, tc.wantType)
			}
		})
	}
}

// TestOpenAIChat_DeepSeekEffortNoneAloneKeepsTheOfficialOffSwitch asserts the
// official reasoning_effort "none" path is used verbatim when no thinking switch
// was requested — that is the documented way to close thinking.
func TestOpenAIChat_DeepSeekEffortNoneAloneKeepsTheOfficialOffSwitch(t *testing.T) {
	t.Parallel()
	ch := make(chan capturedRequest, 1)
	ad := newDeepSeekAdapter(t, ch)

	if _, err := ad.Chat(context.Background(), Request{
		Model:           deepSeekModel,
		Messages:        []Message{TextMessage(RoleUser, "hi")},
		ReasoningEffort: effortNone,
	}, Options{}); err != nil {
		t.Fatalf("Chat error: %v", err)
	}
	body := (<-ch).body
	if got := body["reasoning_effort"]; got != effortNone {
		t.Fatalf("body.reasoning_effort = %v, want %q", got, effortNone)
	}
	if _, present := body["thinking"]; present {
		t.Fatalf("body.thinking = %v, want no switch block", body["thinking"])
	}
}

// TestOpenAIChat_DeepSeekThinkingOffBeatsEffort is the conflict rule documented in
// resolveOpenAIReasoning: the provider states no precedence, so the off side wins
// and the dropped tier is reported — never silently applied.
func TestOpenAIChat_DeepSeekThinkingOffBeatsEffort(t *testing.T) {
	t.Parallel()
	ch := make(chan capturedRequest, 1)
	log, buf := captureLog()
	ad := newDeepSeekAdapter(t, ch, WithOpenAILogger(log))

	if _, err := ad.Chat(context.Background(), Request{
		Model:           deepSeekModel,
		Messages:        []Message{TextMessage(RoleUser, "hi")},
		Thinking:        &Thinking{Enable: boolPtr(false)},
		ReasoningEffort: "high",
	}, Options{}); err != nil {
		t.Fatalf("Chat error: %v", err)
	}
	body := (<-ch).body
	if got, _ := deepSeekThinkingType(body); got != thinkingTypeDisabled {
		t.Fatalf("body.thinking.type = %q, want %q", got, thinkingTypeDisabled)
	}
	if _, present := body["reasoning_effort"]; present {
		t.Fatalf("body.reasoning_effort = %v, want it dropped while thinking is explicitly off", body["reasoning_effort"])
	}
	if rec := buf.String(); !strings.Contains(rec, "explicitly disabled") {
		t.Errorf("log %q, want a WARN explaining the dropped reasoning_effort", rec)
	}
}

// TestOpenAIChat_DeepSeekEffortNoneBeatsThinkingEnabled covers the opposite
// conflict: reasoning_effort "none" and thinking enabled cannot both be honoured,
// so the off side wins and the request carries exactly one switch.
func TestOpenAIChat_DeepSeekEffortNoneBeatsThinkingEnabled(t *testing.T) {
	t.Parallel()
	ch := make(chan capturedRequest, 1)
	log, buf := captureLog()
	ad := newDeepSeekAdapter(t, ch, WithOpenAILogger(log))

	if _, err := ad.Chat(context.Background(), Request{
		Model:           deepSeekModel,
		Messages:        []Message{TextMessage(RoleUser, "hi")},
		Thinking:        &Thinking{Enable: boolPtr(true)},
		ReasoningEffort: effortNone,
	}, Options{}); err != nil {
		t.Fatalf("Chat error: %v", err)
	}
	body := (<-ch).body
	if got, _ := deepSeekThinkingType(body); got != thinkingTypeDisabled {
		t.Fatalf("body.thinking.type = %q, want %q", got, thinkingTypeDisabled)
	}
	if _, present := body["reasoning_effort"]; present {
		t.Fatalf("body.reasoning_effort = %v, want it dropped in favour of the switch", body["reasoning_effort"])
	}
	if rec := buf.String(); !strings.Contains(rec, "contradicts") {
		t.Errorf("log %q, want a WARN about the contradiction", rec)
	}
}

// TestOpenAIChat_DeepSeekThinkingBudgetReportedIgnored asserts a token budget
// (an Anthropic-style directive) is reported as unmappable on the DeepSeek
// chat-completions endpoint instead of opening or closing the switch by guess.
func TestOpenAIChat_DeepSeekThinkingBudgetReportedIgnored(t *testing.T) {
	t.Parallel()
	ch := make(chan capturedRequest, 1)
	log, buf := captureLog()
	ad := newDeepSeekAdapter(t, ch, WithOpenAILogger(log))

	if _, err := ad.Chat(context.Background(), Request{
		Model:    deepSeekModel,
		Messages: []Message{TextMessage(RoleUser, "hi")},
		Thinking: &Thinking{BudgetTokens: 8192},
	}, Options{}); err != nil {
		t.Fatalf("Chat error: %v", err)
	}
	body := (<-ch).body
	if _, present := body["thinking"]; present {
		t.Fatalf("body.thinking = %v, want no switch block", body["thinking"])
	}
	rec := buf.String()
	for _, want := range []string{"level=WARN", "thinking.budget_tokens", "deepseek", deepSeekModel} {
		if !strings.Contains(rec, want) {
			t.Errorf("log %q missing %q", rec, want)
		}
	}
}

// TestOpenAIChat_DeepSeekForcedToolChoiceWithThinkingWarns covers the DeepSeek
// 400 trap: a forcing tool_choice while thinking is on is rejected, and thinking
// is on by default. The adapter only warns — it must never close thinking by
// itself.
func TestOpenAIChat_DeepSeekForcedToolChoiceWithThinkingWarns(t *testing.T) {
	t.Parallel()
	cases := []struct {
		name       string
		thinking   *Thinking
		toolChoice any
		wantWarn   bool
	}{
		{name: "required_with_default_thinking", toolChoice: map[string]any{"type": "required"}, wantWarn: true},
		{name: "named_tool_with_thinking_on", thinking: &Thinking{Enable: boolPtr(true)},
			toolChoice: map[string]any{"type": "function", "function": map[string]any{"name": "x"}}, wantWarn: true},
		{name: "auto_is_not_forcing", toolChoice: map[string]any{"type": "auto"}},
		{name: "forced_with_thinking_off", thinking: &Thinking{Enable: boolPtr(false)},
			toolChoice: map[string]any{"type": "required"}},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()
			ch := make(chan capturedRequest, 1)
			log, buf := captureLog()
			ad := newDeepSeekAdapter(t, ch, WithOpenAILogger(log))
			if _, err := ad.Chat(context.Background(), Request{
				Model:      deepSeekModel,
				Messages:   []Message{TextMessage(RoleUser, "hi")},
				Thinking:   tc.thinking,
				ToolChoice: tc.toolChoice,
			}, Options{}); err != nil {
				t.Fatalf("Chat error: %v", err)
			}
			rec := buf.String()
			if tc.wantWarn {
				for _, want := range []string{"level=WARN", "tool_choice", "deepseek", deepSeekModel} {
					if !strings.Contains(rec, want) {
						t.Errorf("log %q missing %q", rec, want)
					}
				}
				return
			}
			if strings.Contains(rec, "tool_choice") {
				t.Errorf("unexpected tool_choice WARN: %q", rec)
			}
		})
	}
}