package model

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

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

// newDeepSeekAdapter 构建一个 OpenAI 兼容适配器，指向 stub 服务器
// 但按其模型名归类为 DeepSeek，从而让 DeepSeek 映射
// 针对真实请求体被验证。
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 是当前的 DeepSeek 模型名（旧的 deepseek-chat /
// deepseek-reasoner 名称已于 2026-07-24 停用）。
const deepSeekModel = "deepseek-flash"

// deepSeekThinkingType 读取 body.thinking.type，报告该开关是否
// 被发出。
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 钉住官方取值集合，端到
// 端落到请求体上：none/low/high/max 原样通过，四个
// 兼容别名被归一化为 DeepSeek 采用的档位
// （minimal→low、medium/xhigh→high、ultra→max）。旧行为——把 "none"
// 降级到 "low"——把关闭思考变成了开启思考，所以 "none" 必须
// 以 "none" 到达。
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 断言无法识别的
// 取值会被丢弃并上报——绝不会被替换成邻近档位，正是那套
// 「向下取整」逻辑颠倒了调用方的意图。
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 断言 DeepSeek 思考开关
// 真的被发出：显式关闭必须到达线上（DeepSeek 默认开启，
// 所以保持沉默会让思考保持开启），而 nil 不得被变成
// 任何一个取值。
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 断言在未
// 请求 thinking 开关时，官方 reasoning_effort "none" 路径被原样
// 使用——那是关闭思考的记录在案的做法。
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 是 resolveOpenAIReasoning 里
// 记录的冲突规则：提供商未说明优先级，所以关闭一侧获胜，
// 被丢弃的档位会被上报——绝不静默套用。
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 覆盖相反的
// 冲突：reasoning_effort "none" 与 thinking 开启无法同时被
// 尊重，所以关闭一侧获胜，请求只携带一个开关。
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 断言 token 预算
// （Anthropic 风格的指令）在 DeepSeek chat-completions 端点上
// 会被上报为无法映射，而不是靠猜去开或关开关。
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 覆盖 DeepSeek
// 400 陷阱：思考开启时强制型 tool_choice 会被拒绝，而思考
// 默认就是开启。适配器只警告——它绝不能自行
// 关闭思考。
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)
			}
		})
	}
}