package server

import (
	"io"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"
)

// TestRecentRecorderRingBuffer verifies that the recorder keeps at most
// maxRecentEntries and evicts the oldest when full.
func TestRecentRecorderRingBuffer(t *testing.T) {
	rec := NewRecentRecorder()
	for i := 0; i < maxRecentEntries+5; i++ {
		rec.Record(RecentEntry{Method: "POST", Path: "/v1/test", Status: 200})
	}
	entries := rec.Entries()
	if len(entries) != maxRecentEntries {
		t.Fatalf("got %d entries, want %d", len(entries), maxRecentEntries)
	}
}

// TestRecentRecorderNewestFirst verifies entries are returned newest-first.
func TestRecentRecorderNewestFirst(t *testing.T) {
	rec := NewRecentRecorder()
	rec.Record(RecentEntry{Path: "/first"})
	rec.Record(RecentEntry{Path: "/second"})
	rec.Record(RecentEntry{Path: "/third"})
	entries := rec.Entries()
	if len(entries) != 3 {
		t.Fatalf("got %d entries", len(entries))
	}
	if entries[0].Path != "/third" {
		t.Fatalf("first entry = %q, want /third", entries[0].Path)
	}
	if entries[2].Path != "/first" {
		t.Fatalf("last entry = %q, want /first", entries[2].Path)
	}
}

// TestWithRecordingCapturesRequestResponse verifies the middleware captures
// request headers, request body, response status, and response body.
func TestWithRecordingCapturesRequestResponse(t *testing.T) {
	rec := NewRecentRecorder()
	s := &Server{recorder: rec}

	handler := s.withRecording(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusOK)
		w.Write([]byte(`{"result":"ok"}`))
	})

	req := httptest.NewRequest(http.MethodPost, "/v1/chat/completions", strings.NewReader(`{"model":"GLM-4.7","messages":[]}`))
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Authorization", "Bearer sk-secret-key-12345")
	req.Header.Set("User-Agent", "test-client/1.0")
	w := httptest.NewRecorder()
	handler(w, req)

	entries := rec.Entries()
	if len(entries) != 1 {
		t.Fatalf("got %d entries, want 1", len(entries))
	}
	e := entries[0]
	if e.Method != "POST" {
		t.Fatalf("method = %q", e.Method)
	}
	if e.Path != "/v1/chat/completions" {
		t.Fatalf("path = %q", e.Path)
	}
	if e.Status != 200 {
		t.Fatalf("status = %d", e.Status)
	}
	if e.RequestBody != `{"model":"GLM-4.7","messages":[]}` {
		t.Fatalf("request body = %q", e.RequestBody)
	}
	if e.ResponseBody != `{"result":"ok"}` {
		t.Fatalf("response body = %q", e.ResponseBody)
	}
	// Authorization must be masked
	auth, ok := e.RequestHeaders["Authorization"]
	if !ok || !strings.Contains(auth, "****") {
		t.Fatalf("authorization not masked: %q", auth)
	}
	if strings.Contains(auth, "sk-secret-key-12345") {
		t.Fatal("authorization leaked raw key")
	}
	if e.RequestHeaders["Content-Type"] != "application/json" {
		t.Fatalf("content-type = %v", e.RequestHeaders["Content-Type"])
	}
	if e.RequestHeaders["User-Agent"] != "test-client/1.0" {
		t.Fatalf("user-agent = %v", e.RequestHeaders["User-Agent"])
	}
}

// TestWithRecordingCapturesErrors verifies error responses are recorded.
func TestWithRecordingCapturesErrors(t *testing.T) {
	rec := NewRecentRecorder()
	s := &Server{recorder: rec}

	handler := s.withRecording(func(w http.ResponseWriter, r *http.Request) {
		writeOpenAIError(w, http.StatusUnauthorized, "invalid api key", "auth_error", "invalid_api_key")
	})

	req := httptest.NewRequest(http.MethodPost, "/v1/responses", strings.NewReader(`{"input":"hi"}`))
	req.Header.Set("Authorization", "Bearer wrong-key")
	w := httptest.NewRecorder()
	handler(w, req)

	entries := rec.Entries()
	if len(entries) != 1 {
		t.Fatalf("got %d entries, want 1", len(entries))
	}
	e := entries[0]
	if e.Status != 401 {
		t.Fatalf("status = %d, want 401", e.Status)
	}
	if !strings.Contains(e.ResponseBody, "invalid api key") {
		t.Fatalf("response body = %q", e.ResponseBody)
	}
}

// TestGetRecentAPI verifies GET /api/recent returns recorded entries as JSON.
func TestGetRecentAPI(t *testing.T) {
	rec := NewRecentRecorder()
	rec.Record(RecentEntry{Method: "POST", Path: "/v1/chat/completions", Status: 200})
	rec.Record(RecentEntry{Method: "POST", Path: "/v1/responses", Status: 500})
	s := &Server{recorder: rec}

	req := httptest.NewRequest(http.MethodGet, "/api/recent", nil)
	w := httptest.NewRecorder()
	s.getRecent(w, req)

	body, _ := io.ReadAll(w.Body)
	if !strings.Contains(string(body), `"ok":true`) {
		t.Fatalf("response missing ok:true: %s", string(body))
	}
	if !strings.Contains(string(body), "/v1/responses") {
		t.Fatalf("response missing /v1/responses: %s", string(body))
	}
	// newest first
	idxResponses := strings.Index(string(body), "/v1/responses")
	idxChat := strings.Index(string(body), "/v1/chat/completions")
	if idxResponses < 0 || idxChat < 0 || idxResponses > idxChat {
		t.Fatalf("entries not newest-first: %s", string(body))
	}
}