package middleware

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

	"veza-backend-api/internal/models"

	"github.com/gin-gonic/gin"
	"github.com/google/uuid"
)

func init() {
	gin.SetMode(gin.TestMode)
}

func TestAPIKeyRateLimiter_PassthroughWithoutAPIKey(t *testing.T) {
	rl := NewAPIKeyRateLimiter(DefaultAPIKeyRateLimiterConfig())
	defer rl.Stop()

	router := gin.New()
	router.Use(rl.Middleware())
	router.GET("/test", func(c *gin.Context) {
		c.JSON(http.StatusOK, gin.H{"ok": true})
	})

	// Request without api_key in context — should pass through
	w := httptest.NewRecorder()
	req, _ := http.NewRequest("GET", "/test", nil)
	router.ServeHTTP(w, req)

	if w.Code != http.StatusOK {
		t.Errorf("expected 200, got %d", w.Code)
	}
}

func TestAPIKeyRateLimiter_EnforcesReadLimit(t *testing.T) {
	config := &APIKeyRateLimiterConfig{
		ReadLimit:  3,
		WriteLimit: 2,
		Window:     time.Minute,
	}
	rl := NewAPIKeyRateLimiter(config)
	defer rl.Stop()

	keyID := uuid.New()
	apiKey := &models.APIKey{ID: keyID, UserID: uuid.New(), Name: "test"}

	router := gin.New()
	// Simulate auth middleware setting api_key
	router.Use(func(c *gin.Context) {
		c.Set("api_key", apiKey)
		c.Next()
	})
	router.Use(rl.Middleware())
	router.GET("/test", func(c *gin.Context) {
		c.JSON(http.StatusOK, gin.H{"ok": true})
	})

	// First 3 requests should pass
	for i := 0; i < 3; i++ {
		w := httptest.NewRecorder()
		req, _ := http.NewRequest("GET", "/test", nil)
		router.ServeHTTP(w, req)
		if w.Code != http.StatusOK {
			t.Errorf("request %d: expected 200, got %d", i+1, w.Code)
		}
	}

	// 4th request should be rate limited
	w := httptest.NewRecorder()
	req, _ := http.NewRequest("GET", "/test", nil)
	router.ServeHTTP(w, req)
	if w.Code != http.StatusTooManyRequests {
		t.Errorf("4th request: expected 429, got %d", w.Code)
	}

	// Check rate limit headers
	if w.Header().Get("X-RateLimit-Limit") != "3" {
		t.Errorf("expected X-RateLimit-Limit=3, got %s", w.Header().Get("X-RateLimit-Limit"))
	}
	if w.Header().Get("X-RateLimit-Remaining") != "0" {
		t.Errorf("expected X-RateLimit-Remaining=0, got %s", w.Header().Get("X-RateLimit-Remaining"))
	}
}

func TestAPIKeyRateLimiter_EnforcesWriteLimit(t *testing.T) {
	config := &APIKeyRateLimiterConfig{
		ReadLimit:  100,
		WriteLimit: 2,
		Window:     time.Minute,
	}
	rl := NewAPIKeyRateLimiter(config)
	defer rl.Stop()

	keyID := uuid.New()
	apiKey := &models.APIKey{ID: keyID, UserID: uuid.New(), Name: "test"}

	router := gin.New()
	router.Use(func(c *gin.Context) {
		c.Set("api_key", apiKey)
		c.Next()
	})
	router.Use(rl.Middleware())
	router.POST("/test", func(c *gin.Context) {
		c.JSON(http.StatusOK, gin.H{"ok": true})
	})

	// First 2 POST requests should pass
	for i := 0; i < 2; i++ {
		w := httptest.NewRecorder()
		req, _ := http.NewRequest("POST", "/test", nil)
		router.ServeHTTP(w, req)
		if w.Code != http.StatusOK {
			t.Errorf("request %d: expected 200, got %d", i+1, w.Code)
		}
	}

	// 3rd POST should be rate limited
	w := httptest.NewRecorder()
	req, _ := http.NewRequest("POST", "/test", nil)
	router.ServeHTTP(w, req)
	if w.Code != http.StatusTooManyRequests {
		t.Errorf("3rd POST: expected 429, got %d", w.Code)
	}
}

func TestAPIKeyRateLimiter_SeparateKeysHaveSeparateLimits(t *testing.T) {
	config := &APIKeyRateLimiterConfig{
		ReadLimit:  2,
		WriteLimit: 2,
		Window:     time.Minute,
	}
	rl := NewAPIKeyRateLimiter(config)
	defer rl.Stop()

	key1 := &models.APIKey{ID: uuid.New(), UserID: uuid.New(), Name: "key1"}
	key2 := &models.APIKey{ID: uuid.New(), UserID: uuid.New(), Name: "key2"}

	makeRouter := func(apiKey *models.APIKey) *gin.Engine {
		r := gin.New()
		r.Use(func(c *gin.Context) {
			c.Set("api_key", apiKey)
			c.Next()
		})
		r.Use(rl.Middleware())
		r.GET("/test", func(c *gin.Context) {
			c.JSON(http.StatusOK, gin.H{"ok": true})
		})
		return r
	}

	router1 := makeRouter(key1)
	router2 := makeRouter(key2)

	// Exhaust key1's limit
	for i := 0; i < 2; i++ {
		w := httptest.NewRecorder()
		req, _ := http.NewRequest("GET", "/test", nil)
		router1.ServeHTTP(w, req)
	}

	// key1 should be rate limited
	w := httptest.NewRecorder()
	req, _ := http.NewRequest("GET", "/test", nil)
	router1.ServeHTTP(w, req)
	if w.Code != http.StatusTooManyRequests {
		t.Errorf("key1 3rd request: expected 429, got %d", w.Code)
	}

	// key2 should still work
	w = httptest.NewRecorder()
	req, _ = http.NewRequest("GET", "/test", nil)
	router2.ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		t.Errorf("key2 1st request: expected 200, got %d", w.Code)
	}
}

func TestAPIKeyRateLimiter_ReturnsRateLimitHeaders(t *testing.T) {
	config := &APIKeyRateLimiterConfig{
		ReadLimit:  10,
		WriteLimit: 5,
		Window:     time.Hour,
	}
	rl := NewAPIKeyRateLimiter(config)
	defer rl.Stop()

	apiKey := &models.APIKey{ID: uuid.New(), UserID: uuid.New(), Name: "test"}

	router := gin.New()
	router.Use(func(c *gin.Context) {
		c.Set("api_key", apiKey)
		c.Next()
	})
	router.Use(rl.Middleware())
	router.GET("/test", func(c *gin.Context) {
		c.JSON(http.StatusOK, gin.H{"ok": true})
	})

	w := httptest.NewRecorder()
	req, _ := http.NewRequest("GET", "/test", nil)
	router.ServeHTTP(w, req)

	if w.Header().Get("X-RateLimit-Limit") != "10" {
		t.Errorf("expected X-RateLimit-Limit=10, got %s", w.Header().Get("X-RateLimit-Limit"))
	}
	if w.Header().Get("X-RateLimit-Remaining") != "9" {
		t.Errorf("expected X-RateLimit-Remaining=9, got %s", w.Header().Get("X-RateLimit-Remaining"))
	}
	if w.Header().Get("X-RateLimit-Reset") == "" {
		t.Error("expected X-RateLimit-Reset header to be set")
	}
}