package agent

import (
	"context"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"testing"

	"code.littlelan.cn/CarrotAssistant/backend/internal/skill"
)

// TestRenderTemplate covers the {{param}} substitution used to build tool
// requests. It must substitute known args, drop unfilled placeholders, and
// leave templates with no markers untouched.
func TestRenderTemplate(t *testing.T) {
	args := map[string]any{"keyword": "golang", "limit": 10}
	cases := []struct{ in, want string }{
		{"https://x.com/search?q={{keyword}}", "https://x.com/search?q=golang"},
		{"{{limit}}", "10"},
		{"no markers here", "no markers here"},
		{"q={{keyword}}&p={{missing}}", "q=golang&p="},
		{"{{a}}{{b}}", ""}, // both unfilled -> empty
	}
	for _, c := range cases {
		got := renderTemplate(c.in, args)
		if got != c.want {
			t.Errorf("renderTemplate(%q) = %q, want %q", c.in, got, c.want)
		}
	}
}

// TestExecuteReadOnly verifies the default readonly policy blocks mutating
// methods that are neither allow-listed nor confirmation-listed.
func TestExecuteReadOnlyBlocksMutating(t *testing.T) {
	tool := skill.Tool{
		Name: "delete_post",
		Endpoint: skill.Endpoint{Method: "DELETE", URL: "https://example.com/x"},
	}
	out, err := Execute(context.Background(), tool, skill.Permissions{DefaultMode: "readonly"}, nil)
	if err != nil {
		t.Fatalf("execute: %v", err)
	}
	if !out.Denied {
		t.Fatalf("expected Denied, got %+v", out)
	}
}

// TestExecuteConfirmation verifies a mutating tool on the confirmation list
// pauses execution rather than firing the request.
func TestExecuteConfirmation(t *testing.T) {
	called := false
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		called = true
		w.WriteHeader(200)
	}))
	defer srv.Close()

	tool := skill.Tool{
		Name: "delete_post",
		Endpoint: skill.Endpoint{Method: "DELETE", URL: srv.URL + "/x"},
	}
	perms := skill.Permissions{
		DefaultMode:         "readonly",
		RequireConfirmation: []string{"delete_post"},
	}
	out, err := Execute(context.Background(), tool, perms, map[string]any{"id": 1})
	if err != nil {
		t.Fatalf("execute: %v", err)
	}
	if !out.NeedsConfirmation {
		t.Fatalf("expected NeedsConfirmation, got %+v", out)
	}
	if called {
		t.Fatalf("server was called during a confirmation-pending call")
	}
}

// TestExecuteAllowWrite verifies a mutating tool on the allow_write list runs
// immediately against the target site.
func TestExecuteAllowWrite(t *testing.T) {
	gotMethod := ""
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		gotMethod = r.Method
		w.WriteHeader(200)
		_, _ = w.Write([]byte(`{"ok":true}`))
	}))
	defer srv.Close()

	tool := skill.Tool{
		Name: "create_post",
		Endpoint: skill.Endpoint{
			Method: "POST", URL: srv.URL + "/posts",
			Body: `{"title":"{{title}}"}`,
		},
	}
	perms := skill.Permissions{
		DefaultMode: "readonly",
		AllowWrite:  []string{"create_post"},
	}
	out, err := Execute(context.Background(), tool, perms, map[string]any{"title": "hi"})
	if err != nil {
		t.Fatalf("execute: %v", err)
	}
	if out.NeedsConfirmation || out.Denied {
		t.Fatalf("expected direct execution, got %+v", out)
	}
	if gotMethod != "POST" {
		t.Fatalf("expected POST, got %s", gotMethod)
	}
	var resp map[string]any
	if err := json.Unmarshal([]byte(out.Result), &resp); err != nil || resp["ok"] != true {
		t.Fatalf("unexpected result: %s", out.Result)
	}
}

// TestExecuteGET verifies a read-only GET runs without any permission entries.
func TestExecuteGET(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Query().Get("q") != "golang" {
			t.Errorf("query q = %q, want golang", r.URL.Query().Get("q"))
		}
		_, _ = w.Write([]byte(`["post1","post2"]`))
	}))
	defer srv.Close()

	tool := skill.Tool{
		Name: "search",
		Endpoint: skill.Endpoint{
			Method: "GET", URL: srv.URL + "/search",
			Query: map[string]string{"q": "{{q}}"},
		},
	}
	out, err := Execute(context.Background(), tool, skill.Permissions{DefaultMode: "readonly"}, map[string]any{"q": "golang"})
	if err != nil {
		t.Fatalf("execute: %v", err)
	}
	if out.Result != `["post1","post2"]` {
		t.Fatalf("result = %s", out.Result)
	}
}