package main

import (
	"context"
	"errors"
	"strings"
	"testing"
	"time"

	"github.com/volcengine/volcengine-go-sdk/service/arkruntime/model"
)

func TestNormalizeToolRouterConfigDefaults(t *testing.T) {
	cfg := &Config{ToolRouter: ToolRouterConfig{Enabled: true}}
	changed, err := normalizeToolRouterConfig(cfg)
	if err != nil {
		t.Fatal(err)
	}
	if !changed {
		t.Fatal("expected defaults to change config")
	}
	if cfg.ToolRouter.Timeout != defaultToolRouterTimeout {
		t.Fatalf("timeout = %d", cfg.ToolRouter.Timeout)
	}
	if cfg.ToolRouter.MaxTokens != defaultToolRouterMaxTokens {
		t.Fatalf("max_tokens = %d", cfg.ToolRouter.MaxTokens)
	}
	if strings.TrimSpace(cfg.ToolRouter.SystemPrompt) == "" {
		t.Fatal("system prompt should be defaulted")
	}
	if len(cfg.ToolRouter.Tools) != 3 || cfg.ToolRouter.Tools[0].Name != "time" || cfg.ToolRouter.Tools[1].Name != "search" || cfg.ToolRouter.Tools[2].Name != "sql" || !cfg.ToolRouter.Tools[0].Enabled || !cfg.ToolRouter.Tools[1].Enabled || !cfg.ToolRouter.Tools[2].Enabled {
		t.Fatalf("unexpected tools: %#v", cfg.ToolRouter.Tools)
	}
}

func TestNormalizeToolRouterConfigAddsTimeBeforeSQL(t *testing.T) {
	cfg := &Config{ToolRouter: ToolRouterConfig{
		Enabled:      true,
		Timeout:      1,
		MaxTokens:    1,
		SystemPrompt: "tools",
		Tools: []ToolRouteConfig{
			{Name: "search", Enabled: true},
			{Name: "sql", Enabled: true},
		},
	}}
	changed, err := normalizeToolRouterConfig(cfg)
	if err != nil {
		t.Fatal(err)
	}
	if !changed {
		t.Fatal("expected time tool to be added")
	}
	if len(cfg.ToolRouter.Tools) < 3 || cfg.ToolRouter.Tools[0].Name != "time" || cfg.ToolRouter.Tools[2].Name != "sql" {
		t.Fatalf("unexpected tool order: %#v", cfg.ToolRouter.Tools)
	}
}

func TestNormalizeToolRouterConfigDuplicateTools(t *testing.T) {
	cfg := &Config{ToolRouter: ToolRouterConfig{
		Enabled:      true,
		Timeout:      1,
		MaxTokens:    1,
		SystemPrompt: "tools",
		Tools: []ToolRouteConfig{
			{Name: "sql", Enabled: true},
			{Name: " SQL ", Enabled: true},
		},
	}}
	_, err := normalizeToolRouterConfig(cfg)
	if err == nil {
		t.Fatal("expected duplicate tool error")
	}
}

func TestAvailableAgentToolsUsesConfigOrderAndEnabled(t *testing.T) {
	oldRouter := toolRouterState
	oldSearch := searchState
	oldSQL := sqlState
	defer func() {
		toolRouterState = oldRouter
		searchState = oldSearch
		sqlState = oldSQL
	}()

	toolRouterState = &ToolRouterState{cfg: &ToolRouterConfig{
		Enabled: true,
		Tools: []ToolRouteConfig{
			{Name: "search", Enabled: true},
			{Name: "time", Enabled: true, Description: "custom time"},
			{Name: "sql", Enabled: false},
		},
	}}
	searchState = nil
	sqlState = nil

	tools := availableAgentTools(&OpenAIProfile{}, nil)
	if len(tools) != 1 {
		t.Fatalf("tools length = %d", len(tools))
	}
	if tools[0].name != "time" {
		t.Fatalf("tool name = %s", tools[0].name)
	}
	if tools[0].definition.Function == nil || tools[0].definition.Function.Description != "custom time" {
		t.Fatalf("unexpected definition: %#v", tools[0].definition)
	}
}

func TestRunAgentToolLoopAppendsToolMessages(t *testing.T) {
	oldRouter := toolRouterState
	defer func() { toolRouterState = oldRouter }()

	calls := 0
	toolRouterState = &ToolRouterState{cfg: &ToolRouterConfig{
		Enabled:      true,
		Timeout:      1,
		MaxTokens:    128,
		SystemPrompt: "use tools",
		Tools:        []ToolRouteConfig{{Name: "time", Enabled: true}},
	}}
	toolRouterState.complete = func(ctx context.Context, profile *OpenAIProfile, req model.CreateChatCompletionRequest, timeout time.Duration) (model.ChatCompletionResponse, error) {
		calls++
		if req.ToolChoice != model.ToolChoiceStringTypeAuto {
			t.Fatalf("tool choice = %#v", req.ToolChoice)
		}
		if len(req.Tools) != 1 || req.Tools[0].Function == nil || req.Tools[0].Function.Name != "time" {
			t.Fatalf("unexpected tools: %#v", req.Tools)
		}
		if calls == 1 {
			return model.ChatCompletionResponse{Choices: []*model.ChatCompletionChoice{{Message: model.ChatCompletionMessage{ToolCalls: []*model.ToolCall{{ID: "call_1", Type: model.ToolTypeFunction, Function: model.FunctionCall{Name: "time", Arguments: `{"reason":"需要当前日期"}`}}}}}}}, nil
		}
		return model.ChatCompletionResponse{Choices: []*model.ChatCompletionChoice{{Message: model.ChatCompletionMessage{Content: stringContent("done")}}}}, nil
	}

	messages, err := runAgentToolLoop(context.Background(), &OpenAIProfile{Config: OpenAIConfig{Model: "test"}}, []ChatMessage{{Role: "user", Content: "今天几号"}}, nil)
	if err != nil {
		t.Fatal(err)
	}
	if calls != 2 {
		t.Fatalf("calls = %d", calls)
	}
	if len(messages) < 4 {
		t.Fatalf("expected system/user/assistant/tool messages, got %d", len(messages))
	}
	last := messages[len(messages)-1]
	if last.Role != model.ChatMessageRoleTool || last.ToolCallID != "call_1" {
		t.Fatalf("unexpected last message: %#v", last)
	}
	if last.Content == nil || last.Content.StringValue == nil || !strings.Contains(*last.Content.StringValue, "时间工具结果") {
		t.Fatalf("unexpected tool content: %#v", last.Content)
	}
}

func TestExecuteAgentToolCallUnknownAndError(t *testing.T) {
	unknown := executeAgentToolCall(context.Background(), &model.ToolCall{ID: "1", Type: model.ToolTypeFunction, Function: model.FunctionCall{Name: "missing"}}, map[string]agentTool{}, nil)
	if !strings.Contains(unknown, "未知工具") {
		t.Fatalf("unknown result = %q", unknown)
	}

	failed := executeAgentToolCall(context.Background(), &model.ToolCall{ID: "2", Type: model.ToolTypeFunction, Function: model.FunctionCall{Name: "boom"}}, map[string]agentTool{
		"boom": {name: "boom", execute: func(context.Context, string) (string, error) { return "", errors.New("bad args") }},
	}, nil)
	if !strings.Contains(failed, "bad args") {
		t.Fatalf("failed result = %q", failed)
	}
}

func TestRunAgentToolLoopMaxIterations(t *testing.T) {
	oldRouter := toolRouterState
	defer func() { toolRouterState = oldRouter }()

	toolRouterState = &ToolRouterState{cfg: &ToolRouterConfig{
		Enabled:      true,
		Timeout:      1,
		MaxTokens:    128,
		SystemPrompt: "use tools",
		Tools:        []ToolRouteConfig{{Name: "time", Enabled: true}},
	}}
	toolRouterState.complete = func(context.Context, *OpenAIProfile, model.CreateChatCompletionRequest, time.Duration) (model.ChatCompletionResponse, error) {
		return model.ChatCompletionResponse{Choices: []*model.ChatCompletionChoice{{Message: model.ChatCompletionMessage{ToolCalls: []*model.ToolCall{{ID: "loop", Type: model.ToolTypeFunction, Function: model.FunctionCall{Name: "time", Arguments: `{}`}}}}}}}, nil
	}

	messages, err := runAgentToolLoop(context.Background(), &OpenAIProfile{Config: OpenAIConfig{Model: "test"}}, []ChatMessage{{Role: "user", Content: "今天"}}, nil)
	if err != nil {
		t.Fatal(err)
	}
	last := messages[len(messages)-1]
	if last.Role != model.ChatMessageRoleSystem || last.Content == nil || last.Content.StringValue == nil || !strings.Contains(*last.Content.StringValue, "工具调用轮数已达到上限") {
		t.Fatalf("unexpected last message: %#v", last)
	}
}