package client

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

	"gitea.mrixs.me/Mrixs/yandex-music-api-go/internal/models"
	"gitea.mrixs.me/Mrixs/yandex-music-api-go/internal/utils"
)

func TestClient_GetTracks(t *testing.T) {
	tests := []struct {
		name           string
		trackIDs       []string
		mockResponse   []byte
		mockError      error
		expectError    bool
		expectedTracks int
		checkTrack     func(*testing.T, *models.Track)
	}{
		{
			name:     "single track",
			trackIDs: []string{"12345"},
			mockResponse: []byte(`{
				"result": [
					{
						"id": "12345",
						"title": "Test Track",
						"duration_ms": 180000,
						"storage_id": "67890",
						"cover_uri": "https://example.com/cover.jpg",
						"genre": "rock",
						"version": "album",
						"explicit": false,
						"available": true,
						"available_for_premium_users": true,
						"r128": -12.5,
						"track_sharing_flag": "allowed",
						"artists": [{"id": "1", "name": "Artist 1", "cover_uri": "https://example.com/artist.jpg"}],
						"albums": [{"id": "789", "title": "Test Album", "cover_uri": "https://example.com/album.jpg", "year": 2023}],
						"major": {"id": "major1", "name": "Major Label", "description": "Big label"},
						"lyrics": {"id": "lyr1", "text": "Test lyrics", "available": true, "has_text": true}
					}
				]
			}`),
			expectedTracks: 1,
			checkTrack: func(t *testing.T, tr *models.Track) {
				if tr.ID != "12345" {
					t.Errorf("Expected ID '12345', got '%s'", tr.ID)
				}
				if tr.Title != "Test Track" {
					t.Errorf("Expected Title 'Test Track', got '%s'", tr.Title)
				}
				if tr.DurationMs != 180000 {
					t.Errorf("Expected DurationMs 180000, got %d", tr.DurationMs)
				}
				if len(tr.Artists) != 1 {
					t.Errorf("Expected 1 artist, got %d", len(tr.Artists))
				}
				if tr.Major == nil || tr.Major.Name != "Major Label" {
					t.Errorf("Expected Major 'Major Label'")
				}
				if tr.Lyrics == nil || tr.Lyrics.Text != "Test lyrics" {
					t.Errorf("Expected Lyrics 'Test lyrics'")
				}
			},
		},
		{
			name:     "multiple tracks",
			trackIDs: []string{"12345", "67890"},
			mockResponse: []byte(`{
				"result": [
					{"id": "12345", "title": "Track 1", "duration_ms": 100000, "storage_id": "1", "cover_uri": "", "genre": "", "version": "", "explicit": false, "available": true, "available_for_premium_users": true, "r128": 0, "track_sharing_flag": "", "artists": [], "albums": []},
					{"id": "67890", "title": "Track 2", "duration_ms": 200000, "storage_id": "2", "cover_uri": "", "genre": "", "version": "", "explicit": false, "available": true, "available_for_premium_users": true, "r128": 0, "track_sharing_flag": "", "artists": [], "albums": []}
				]
			}`),
			expectedTracks: 2,
			checkTrack: func(t *testing.T, tr *models.Track) {
				if tr.ID != "12345" && tr.ID != "67890" {
					t.Errorf("Unexpected track ID: %s", tr.ID)
				}
			},
		},
		{
			name:           "empty track IDs",
			trackIDs:       []string{},
			mockResponse:   nil,
			expectedTracks: 0,
		},
		{
			name:           "nil track IDs",
			trackIDs:       nil,
			mockResponse:   nil,
			expectedTracks: 0,
		},
		{
			name:        "API error",
			trackIDs:    []string{"12345"},
			mockError:   utils.NewYandexMusicError("not found", utils.ErrNotFound),
			expectError: true,
		},
		{
			name:           "empty result",
			trackIDs:       []string{"nonexistent"},
			mockResponse:   []byte(`{"result": []}`),
			expectedTracks: 0,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			var server *httptest.Server
			if tt.mockError != nil || tt.mockResponse != nil {
				server = testServer(func(w http.ResponseWriter, r *http.Request) {
					if r.URL.Path != "/tracks" {
						t.Errorf("Expected path '/tracks', got '%s'", r.URL.Path)
					}
					if tt.mockError != nil {
						w.WriteHeader(http.StatusInternalServerError)
						w.Header().Set("Content-Type", "application/json")
						w.Write([]byte(`{"error": "not found"}`))
						return
					}
					w.Header().Set("Content-Type", "application/json")
					w.Write(tt.mockResponse)
				})
				defer server.Close()
			}

			var client *Client
			if server != nil {
				client = newTestClient(server.URL)
			} else {
				client = newTestClient("http://localhost:9999")
			}

			tracks, err := client.GetTracks(context.Background(), tt.trackIDs)

			if tt.expectError {
				if err == nil {
					t.Error("Expected error, got nil")
				}
				return
			}

			if err != nil {
				t.Fatalf("Unexpected error: %v", err)
			}

			if len(tracks) != tt.expectedTracks {
				t.Errorf("Expected %d tracks, got %d", tt.expectedTracks, len(tracks))
				return
			}

			if tt.checkTrack != nil {
				for _, track := range tracks {
					tt.checkTrack(t, track)
				}
			}

			// Verify client is set on tracks
			for _, track := range tracks {
				if track.GetClient() == nil {
					t.Error("Client not set on track")
				}
			}
		})
	}
}

func TestClient_GetTrack(t *testing.T) {
	tests := []struct {
		name         string
		trackID      string
		mockResponse []byte
		mockError    error
		expectError  bool
		checkTrack   func(*testing.T, *models.Track)
	}{
		{
			name:    "success",
			trackID: "12345",
			mockResponse: []byte(`{
				"result": [
					{
						"id": "12345",
						"title": "Test Track",
						"duration_ms": 180000,
						"storage_id": "67890",
						"cover_uri": "https://example.com/cover.jpg",
						"genre": "rock",
						"version": "album",
						"explicit": false,
						"available": true,
						"available_for_premium_users": true,
						"r128": -12.5,
						"track_sharing_flag": "allowed",
						"artists": [{"id": "1", "name": "Artist 1", "cover_uri": "https://example.com/artist.jpg"}],
						"albums": [{"id": "789", "title": "Test Album", "cover_uri": "https://example.com/album.jpg", "year": 2023}],
						"major": {"id": "major1", "name": "Major Label", "description": "Big label"},
						"lyrics": {"id": "lyr1", "text": "Test lyrics", "available": true, "has_text": true}
					}
				]
			}`),
			checkTrack: func(t *testing.T, tr *models.Track) {
				if tr.ID != "12345" {
					t.Errorf("Expected ID '12345', got '%s'", tr.ID)
				}
				if tr.Title != "Test Track" {
					t.Errorf("Expected Title 'Test Track', got '%s'", tr.Title)
				}
			},
		},
		{
			name:         "not found",
			trackID:      "nonexistent",
			mockResponse: []byte(`{"result": []}`),
			expectError:  true,
		},
		{
			name:        "API error",
			trackID:     "12345",
			mockError:   utils.NewYandexMusicError("unauthorized", utils.ErrUnauthorized),
			expectError: true,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			var server *httptest.Server
			if tt.mockError != nil || tt.mockResponse != nil {
				server = testServer(func(w http.ResponseWriter, r *http.Request) {
					if r.URL.Path != "/tracks" {
						t.Errorf("Expected path '/tracks', got '%s'", r.URL.Path)
					}
					if r.URL.Query().Get("track-ids") != tt.trackID {
						t.Errorf("Expected track-ids '%s', got '%s'", tt.trackID, r.URL.Query().Get("track-ids"))
					}
					if tt.mockError != nil {
						w.WriteHeader(http.StatusUnauthorized)
						w.Header().Set("Content-Type", "application/json")
						w.Write([]byte(`{"error": "unauthorized"}`))
						return
					}
					w.Header().Set("Content-Type", "application/json")
					w.Write(tt.mockResponse)
				})
				defer server.Close()
			}

			var client *Client
			if server != nil {
				client = newTestClient(server.URL)
			} else {
				client = newTestClient("http://localhost:9999")
			}

			track, err := client.GetTrack(context.Background(), tt.trackID)

			if tt.expectError {
				if err == nil {
					t.Error("Expected error, got nil")
				}
				return
			}

			if err != nil {
				t.Fatalf("Unexpected error: %v", err)
			}

			if track == nil {
				t.Fatal("Expected track, got nil")
			}

			if tt.checkTrack != nil {
				tt.checkTrack(t, track)
			}

			if track.GetClient() == nil {
				t.Error("Client not set on track")
			}
		})
	}
}

func TestClient_SearchTracks(t *testing.T) {
	// Create test server
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path != "/search" {
			http.NotFound(w, r)
			return
		}

		query := r.URL.Query()
		if query.Get("type") != "track" {
			t.Errorf("Expected type=track, got %s", query.Get("type"))
		}

		page := query.Get("page")
		pageSize := query.Get("page_size")

		response := map[string]interface{}{
			"result": map[string]interface{}{
				"tracks": map[string]interface{}{
					"total": 2,
					"results": []map[string]interface{}{
						{
							"id":                          "1",
							"title":                       "Track 1",
							"duration_ms":                 100000,
							"storage_id":                  "1",
							"cover_uri":                   "",
							"genre":                       "",
							"version":                     "",
							"explicit":                    false,
							"available":                   true,
							"available_for_premium_users": true,
							"r128":                        0,
							"track_sharing_flag":          "",
							"artists":                     []interface{}{},
							"albums":                      []interface{}{},
						},
						{
							"id":                          "2",
							"title":                       "Track 2",
							"duration_ms":                 200000,
							"storage_id":                  "2",
							"cover_uri":                   "",
							"genre":                       "",
							"version":                     "",
							"explicit":                    false,
							"available":                   true,
							"available_for_premium_users": true,
							"r128":                        0,
							"track_sharing_flag":          "",
							"artists":                     []interface{}{},
							"albums":                      []interface{}{},
						},
					},
				},
			},
		}

		// Verify pagination
		if page != "1" || pageSize != "20" {
			t.Errorf("Unexpected pagination: page=%s, page_size=%s", page, pageSize)
		}

		w.Header().Set("Content-Type", "application/json")
		json.NewEncoder(w).Encode(response)
	}))
	defer server.Close()

	// Create client with test server URL
	config := ClientConfig{
		BaseURL: server.URL,
		Token:   "test-token",
	}
	client := NewClient(config)

	ctx := context.Background()
	result, err := client.SearchTracks(ctx, "test query", 1, 20)
	if err != nil {
		t.Fatalf("SearchTracks failed: %v", err)
	}

	if result == nil {
		t.Fatal("Expected search result, got nil")
	}

	if result.Total != 2 {
		t.Errorf("Expected total 2, got %d", result.Total)
	}

	if len(result.Results) != 2 {
		t.Errorf("Expected 2 results, got %d", len(result.Results))
	}

	for i, track := range result.Results {
		if track.GetClient() == nil {
			t.Errorf("Track %d: Client not set", i)
		}
		if track.ID != "1" && track.ID != "2" {
			t.Errorf("Track %d: Unexpected ID %s", i, track.ID)
		}
	}
}

func TestClient_SearchTracks_Mocked(t *testing.T) {
	server := testServer(func(w http.ResponseWriter, r *http.Request) {
		if r.Method != http.MethodGet || r.URL.Path != "/search" {
			t.Errorf("Unexpected request: %s %s", r.Method, r.URL.Path)
			return
		}
		if r.URL.Query().Get("type") != "track" {
			t.Errorf("Expected type=track, got %s", r.URL.Query().Get("type"))
		}

		mockSearchResult := map[string]interface{}{
			"result": map[string]interface{}{
				"tracks": map[string]interface{}{
					"total": 2,
					"results": []map[string]interface{}{
						{
							"id":                          "1",
							"title":                       "Track 1",
							"duration_ms":                 100000,
							"storage_id":                  "1",
							"cover_uri":                   "",
							"genre":                       "",
							"version":                     "",
							"explicit":                    false,
							"available":                   true,
							"available_for_premium_users": true,
							"r128":                        0,
							"track_sharing_flag":          "",
							"artists":                     []interface{}{},
							"albums":                      []interface{}{},
						},
						{
							"id":                          "2",
							"title":                       "Track 2",
							"duration_ms":                 200000,
							"storage_id":                  "2",
							"cover_uri":                   "",
							"genre":                       "",
							"version":                     "",
							"explicit":                    false,
							"available":                   true,
							"available_for_premium_users": true,
							"r128":                        0,
							"track_sharing_flag":          "",
							"artists":                     []interface{}{},
							"albums":                      []interface{}{},
						},
					},
				},
			},
		}

		w.Header().Set("Content-Type", "application/json")
		json.NewEncoder(w).Encode(mockSearchResult)
	})
	defer server.Close()

	client := newTestClient(server.URL)

	ctx := context.Background()
	result, err := client.SearchTracks(ctx, "test query", 1, 20)

	if err != nil {
		t.Fatalf("SearchTracks failed: %v", err)
	}

	if result == nil {
		t.Fatal("Expected search result, got nil")
	}

	if result.Total != 2 {
		t.Errorf("Expected total 2, got %d", result.Total)
	}

	if len(result.Results) != 2 {
		t.Errorf("Expected 2 results, got %d", len(result.Results))
	}

	for i, track := range result.Results {
		if track.GetClient() == nil {
			t.Errorf("Track %d: Client not set", i)
		}
	}

	// Test error case
	errorServer := testServer(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusInternalServerError)
		w.Header().Set("Content-Type", "application/json")
		w.Write([]byte(`{"error": "network error"}`))
	})
	defer errorServer.Close()

	errorClient := newTestClient(errorServer.URL)
	_, err = errorClient.SearchTracks(ctx, "test", 1, 20)
	if err == nil {
		t.Error("Expected error for network failure")
	}
	if !utils.IsNetworkError(err) {
		t.Errorf("Expected network error, got %v", err)
	}
}

func TestJoinIDs(t *testing.T) {
	tests := []struct {
		name     string
		input    []string
		expected string
	}{
		{"empty", []string{}, ""},
		{"single", []string{"123"}, "123"},
		{"multiple", []string{"123", "456", "789"}, "123,456,789"},
		{"with empty", []string{"123", "", "456"}, "123,,456"},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			result := joinIDs(tt.input)
			if result != tt.expected {
				t.Errorf("joinIDs(%v) = %q, want %q", tt.input, result, tt.expected)
			}
		})
	}
}