package tools

import (
	"context"
	"encoding/json"
	"os"
	"path/filepath"
	"strings"
	"testing"
)

type deferredEcho struct{}

func (deferredEcho) Name() string        { return "mcp__late__echo" }
func (deferredEcho) Description() string { return "回声延迟工具" }
func (deferredEcho) Parameters() json.RawMessage {
	return json.RawMessage(`{"type":"object","properties":{"text":{"type":"string"}}}`)
}
func (deferredEcho) Exposure() string { return ExposureDeferred }
func (deferredEcho) Execute(_ context.Context, args json.RawMessage) (Result, error) {
	var a struct {
		Text string `json:"text"`
	}
	_ = json.Unmarshal(args, &a)
	return Result{Content: "echo " + a.Text}, nil
}

func TestDeferredToolStaysOutOfDeclsUntilCalledByName(t *testing.T) {
	reg := NewRegistry(t.TempDir())
	reg.Register(deferredEcho{})
	for _, d := range reg.Decls() {
		if d.Name == "mcp__late__echo" {
			t.Fatal("deferred tool must not be listed")
		}
	}
	found := reg.Search("回声")
	if !strings.Contains(found, "mcp__late__echo") || !strings.Contains(found, `"text"`) {
		t.Fatalf("search %q", found)
	}
	res := reg.Execute(context.Background(), "call_tool", json.RawMessage(`{"name":"mcp__late__echo","arguments":{"text":"hi"}}`))
	if res.IsError || res.Content != "echo hi" {
		t.Fatalf("call %+v", res)
	}
	denied := reg.Execute(context.Background(), "call_tool", json.RawMessage(`{"name":"run_shell"}`))
	if !denied.IsError {
		t.Fatalf("forbidden call should fail: %+v", denied)
	}
}

func TestActivatedNamesRestoreWithoutEnteringDecls(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "activated.json")
	reg := NewRegistry(dir)
	reg.SetActivationFile(path)
	reg.Register(deferredEcho{})
	_ = reg.Execute(context.Background(), "call_tool", json.RawMessage(`{"name":"mcp__late__echo","arguments":{"text":"x"}}`))
	if _, err := os.Stat(path); err != nil {
		t.Fatal(err)
	}
	next := NewRegistry(dir)
	next.SetActivationFile(path)
	if err := next.RestoreActivated(); err != nil {
		t.Fatal(err)
	}
	next.Register(deferredEcho{})
	names := next.Activated()
	if len(names) != 1 || names[0] != "mcp__late__echo" {
		t.Fatalf("activated %+v", names)
	}
	for _, d := range next.Decls() {
		if d.Name == "mcp__late__echo" {
			t.Fatal("restored tool must stay out of the list")
		}
	}
}