package lobbyclient

import (
	"context"
	"errors"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"galaxy/rtmanager/internal/ports"
)

func newTestClient(t *testing.T, baseURL string, timeout time.Duration) *Client {
	t.Helper()
	client, err := NewClient(Config{BaseURL: baseURL, RequestTimeout: timeout})
	require.NoError(t, err)
	t.Cleanup(func() { _ = client.Close() })
	return client
}

func TestNewClientValidatesConfig(t *testing.T) {
	cases := map[string]Config{
		"empty base url":        {BaseURL: "", RequestTimeout: time.Second},
		"non-absolute base url": {BaseURL: "lobby:8095", RequestTimeout: time.Second},
		"non-positive timeout":  {BaseURL: "http://lobby:8095", RequestTimeout: 0},
	}
	for name, cfg := range cases {
		t.Run(name, func(t *testing.T) {
			_, err := NewClient(cfg)
			require.Error(t, err)
		})
	}
}

func TestGetGameSuccess(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		require.Equal(t, http.MethodGet, r.Method)
		require.Equal(t, "/api/v1/internal/games/game-1", r.URL.Path)
		require.Equal(t, "application/json", r.Header.Get("Accept"))
		w.Header().Set("Content-Type", "application/json")
		_, _ = w.Write([]byte(`{
			"game_id": "game-1",
			"game_name": "Sample",
			"status": "running",
			"target_engine_version": "1.4.2",
			"current_turn": 0,
			"runtime_status": "running"
		}`))
	}))
	defer server.Close()

	client := newTestClient(t, server.URL, time.Second)
	got, err := client.GetGame(context.Background(), "game-1")
	require.NoError(t, err)
	assert.Equal(t, "game-1", got.GameID)
	assert.Equal(t, "running", got.Status)
	assert.Equal(t, "1.4.2", got.TargetEngineVersion)
}

func TestGetGameNotFound(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusNotFound)
		_, _ = w.Write([]byte(`{"error":{"code":"not_found","message":"no such game"}}`))
	}))
	defer server.Close()

	client := newTestClient(t, server.URL, time.Second)
	_, err := client.GetGame(context.Background(), "missing")
	require.Error(t, err)
	assert.True(t, errors.Is(err, ports.ErrLobbyGameNotFound))
	assert.False(t, errors.Is(err, ports.ErrLobbyUnavailable))
}

func TestGetGameInternalErrorMapsToUnavailable(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusInternalServerError)
		_, _ = w.Write([]byte(`{"error":{"code":"internal_error","message":"boom"}}`))
	}))
	defer server.Close()

	client := newTestClient(t, server.URL, time.Second)
	_, err := client.GetGame(context.Background(), "x")
	require.Error(t, err)
	assert.True(t, errors.Is(err, ports.ErrLobbyUnavailable))
	assert.Contains(t, err.Error(), "500")
	assert.Contains(t, err.Error(), "internal_error")
}

func TestGetGameTimeoutMapsToUnavailable(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		time.Sleep(150 * time.Millisecond)
		_, _ = w.Write([]byte(`{}`))
	}))
	defer server.Close()

	client := newTestClient(t, server.URL, 50*time.Millisecond)
	_, err := client.GetGame(context.Background(), "x")
	require.Error(t, err)
	assert.True(t, errors.Is(err, ports.ErrLobbyUnavailable))
}

func TestGetGameSuccessMissingGameIDIsUnavailable(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		_, _ = w.Write([]byte(`{"status":"running"}`))
	}))
	defer server.Close()

	client := newTestClient(t, server.URL, time.Second)
	_, err := client.GetGame(context.Background(), "x")
	require.Error(t, err)
	assert.True(t, errors.Is(err, ports.ErrLobbyUnavailable))
	assert.Contains(t, err.Error(), "missing game_id")
}

func TestGetGameRejectsBadInput(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		t.Fatal("must not contact lobby on bad input")
	}))
	defer server.Close()

	client := newTestClient(t, server.URL, time.Second)
	t.Run("empty game id", func(t *testing.T) {
		_, err := client.GetGame(context.Background(), " ")
		require.Error(t, err)
		assert.Contains(t, err.Error(), "game id")
	})
	t.Run("canceled context", func(t *testing.T) {
		ctx, cancel := context.WithCancel(context.Background())
		cancel()
		_, err := client.GetGame(ctx, "x")
		require.Error(t, err)
		assert.True(t, errors.Is(err, context.Canceled))
	})
}

func TestCloseReleasesConnections(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		_, _ = w.Write([]byte(`{"game_id":"x","status":"running","target_engine_version":"1.0.0"}`))
	}))
	defer server.Close()

	client := newTestClient(t, server.URL, time.Second)
	_, err := client.GetGame(context.Background(), "x")
	require.NoError(t, err)
	assert.NoError(t, client.Close())
	assert.NoError(t, client.Close()) // idempotent
}