package governance

import (
	"sync"
	"testing"
	"time"
)

// ============================================================================
// CRITICAL: Multiple VKs Sharing Team Budget
// ============================================================================

// TestMultipleVKsSharingTeamBudgetFairness verifies that when multiple VKs share a team budget,
// one VK cannot monopolize the budget and block others.
// Budget enforcement is POST-HOC: the request that exceeds the budget is allowed,
// but subsequent requests are blocked.
func TestMultipleVKsSharingTeamBudgetFairness(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create a team with a small budget that will be exceeded quickly
	teamName := "test-team-shared-budget-" + generateRandomID()
	teamBudget := 0.01 // $0.01 for team - small enough to exceed in a few requests
	teamResetDuration := "1h"

	createTeamResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/teams",
		Body: CreateTeamRequest{
			Name: teamName,
			Budgets: []BudgetRequest{{
				MaxLimit:      teamBudget,
				ResetDuration: teamResetDuration,
			}},
		},
	})

	if createTeamResp.StatusCode != 200 {
		t.Fatalf("Failed to create team: status %d", createTeamResp.StatusCode)
	}

	teamID := ExtractIDFromResponse(t, createTeamResp)
	testData.AddTeam(teamID)

	t.Logf("Created team with shared budget: $%.4f", teamBudget)

	// Create VK1 assigned to team
	vk1Name := "test-vk1-shared-" + generateRandomID()
	createVK1Resp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name:   vk1Name,
			TeamID: &teamID,
		},
	})

	if createVK1Resp.StatusCode != 200 {
		t.Fatalf("Failed to create VK1: status %d", createVK1Resp.StatusCode)
	}

	vk1ID := ExtractIDFromResponse(t, createVK1Resp)
	testData.AddVirtualKey(vk1ID)

	vk1 := createVK1Resp.Body["virtual_key"].(map[string]interface{})
	vk1Value := vk1["value"].(string)

	// Create VK2 assigned to same team
	vk2Name := "test-vk2-shared-" + generateRandomID()
	createVK2Resp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name:   vk2Name,
			TeamID: &teamID,
		},
	})

	if createVK2Resp.StatusCode != 200 {
		t.Fatalf("Failed to create VK2: status %d", createVK2Resp.StatusCode)
	}

	vk2ID := ExtractIDFromResponse(t, createVK2Resp)
	testData.AddVirtualKey(vk2ID)

	vk2 := createVK2Resp.Body["virtual_key"].(map[string]interface{})
	vk2Value := vk2["value"].(string)

	t.Logf("Created VK1 and VK2 both assigned to same team")

	// Use VK1 to consume team budget until it's exceeded
	// Budget enforcement is POST-HOC: request that exceeds is allowed, next is blocked
	consumedBudget := 0.0
	requestNum := 1
	shouldStop := false

	for requestNum <= 150 { // Need many requests since each costs ~$0.0001
		resp := MakeRequest(t, APIRequest{
			Method: "POST",
			Path:   "/v1/chat/completions",
			Body: ChatCompletionRequest{
				Model: "openai/gpt-4o",
				Messages: []ChatMessage{
					{
						Role:    "user",
						Content: "Hi, how are you?",
					},
				},
			},
			VKHeader: &vk1Value,
		})

		if resp.StatusCode >= 400 {
			// VK1 got rejected - budget exceeded
			if CheckErrorMessage(t, resp, "budget") {
				t.Logf("VK1 request %d rejected: team budget exceeded at $%.6f/$%.4f", requestNum, consumedBudget, teamBudget)
				break
			} else {
				t.Fatalf("VK1 request %d failed with unexpected error: %v", requestNum, resp.Body)
			}
		}

		// Extract cost from response
		if usage, ok := resp.Body["usage"].(map[string]interface{}); ok {
			if prompt, ok := usage["prompt_tokens"].(float64); ok {
				if completion, ok := usage["completion_tokens"].(float64); ok {
					cost, _ := CalculateCost("openai/gpt-4o", int(prompt), int(completion))
					consumedBudget += cost
					t.Logf("VK1 request %d: cost=$%.6f, total consumed=$%.6f/$%.4f", requestNum, cost, consumedBudget, teamBudget)
				}
			}
		}

		requestNum++

		if shouldStop {
			break
		}

		if consumedBudget >= teamBudget {
			shouldStop = true
		}
	}

	// Verify that team budget was indeed exceeded
	if consumedBudget < teamBudget {
		t.Fatalf("Could not exceed team budget after %d requests (consumed $%.6f / $%.4f)", requestNum-1, consumedBudget, teamBudget)
	}

	t.Logf("Team budget exhausted by VK1: $%.6f consumed (limit: $%.4f)", consumedBudget, teamBudget)

	// Now try VK2 - should be rejected because team budget was exhausted by VK1
	resp2 := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "Hello how are you?",
				},
			},
		},
		VKHeader: &vk2Value,
	})

	// VK2 should be rejected because team budget was consumed by VK1
	if resp2.StatusCode < 400 {
		t.Fatalf("VK2 request should be rejected due to shared team budget exhaustion but got status %d", resp2.StatusCode)
	}

	if !CheckErrorMessage(t, resp2, "budget") {
		t.Fatalf("Expected budget error for VK2 but got: %v", resp2.Body)
	}

	t.Logf("Multiple VKs sharing team budget verified ✓")
	t.Logf("VK2 correctly rejected when team budget exhausted by VK1")
}

// ============================================================================
// CRITICAL: Full Budget Hierarchy Validation (All 4 Levels)
// ============================================================================

// TestFullBudgetHierarchyEnforcement verifies that ALL levels of hierarchy are checked:
// Provider Budget → VK Budget → Team Budget → Customer Budget
// Budget enforcement happens AFTER limit is exceeded - the request that exceeds is allowed,
// but subsequent requests are blocked.
func TestFullBudgetHierarchyEnforcement(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create customer with high budget
	customerName := "test-customer-hierarchy-" + generateRandomID()
	customerResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/customers",
		Body: CreateCustomerRequest{
			Name: customerName,
			Budget: &BudgetRequest{
				MaxLimit:      1000.0, // Very high
				ResetDuration: "1h",
			},
		},
	})

	if customerResp.StatusCode != 200 {
		t.Fatalf("Failed to create customer: status %d", customerResp.StatusCode)
	}

	customerID := ExtractIDFromResponse(t, customerResp)
	testData.AddCustomer(customerID)

	// Create team under customer with medium budget
	teamName := "test-team-hierarchy-" + generateRandomID()
	teamResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/teams",
		Body: CreateTeamRequest{
			Name:       teamName,
			CustomerID: &customerID,
			Budgets: []BudgetRequest{{
				MaxLimit:      100.0, // Medium
				ResetDuration: "1h",
			}},
		},
	})

	if teamResp.StatusCode != 200 {
		t.Fatalf("Failed to create team: status %d", teamResp.StatusCode)
	}

	teamID := ExtractIDFromResponse(t, teamResp)
	testData.AddTeam(teamID)

	// Create VK under team with lower budget
	// Provider budget is MOST RESTRICTIVE at $0.01 - should be exceeded after 2-3 requests
	vkName := "test-vk-hierarchy-" + generateRandomID()
	vkBudget := 0.1        // $0.1
	providerBudget := 0.01 // $0.01 - MOST RESTRICTIVE
	createVKResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name:   vkName,
			TeamID: &teamID,
			Budget: &BudgetRequest{
				MaxLimit:      vkBudget,
				ResetDuration: "1h",
			},
			ProviderConfigs: []ProviderConfigRequest{
				{
					Provider:      "openai",
					Weight:        float64Ptr(1.0),
					AllowedModels: []string{"*"},
					KeyIDs:        []string{"*"},
					Budget: &BudgetRequest{
						MaxLimit:      providerBudget,
						ResetDuration: "1h",
					},
				},
			},
		},
	})

	if createVKResp.StatusCode != 200 {
		t.Fatalf("Failed to create VK: status %d", createVKResp.StatusCode)
	}

	vkID := ExtractIDFromResponse(t, createVKResp)
	testData.AddVirtualKey(vkID)

	vk := createVKResp.Body["virtual_key"].(map[string]interface{})
	vkValue := vk["value"].(string)

	t.Logf("Created full hierarchy:")
	t.Logf("  Customer Budget: $1000.0 (not limiting)")
	t.Logf("  Team Budget: $100.0 (not limiting)")
	t.Logf("  VK Budget: $%.2f (not limiting)", vkBudget)
	t.Logf("  Provider Budget: $%.2f (MOST RESTRICTIVE)", providerBudget)

	// Make requests until provider budget is exceeded
	// Budget enforcement: request that exceeds is allowed, NEXT request is blocked
	consumedBudget := 0.0
	requestNum := 1
	var lastSuccessfulCost float64
	shouldStop := false

	for requestNum <= 20 {
		resp := MakeRequest(t, APIRequest{
			Method: "POST",
			Path:   "/v1/chat/completions",
			Body: ChatCompletionRequest{
				Model: "openai/gpt-4o",
				Messages: []ChatMessage{
					{
						Role:    "user",
						Content: "Test hierarchy enforcement request " + string(rune('0'+requestNum%10)),
					},
				},
			},
			VKHeader: &vkValue,
		})

		if resp.StatusCode >= 400 {
			// Request failed - check if it's due to budget
			if CheckErrorMessage(t, resp, "budget") {
				t.Logf("Request %d correctly rejected: budget exceeded at provider level", requestNum)
				t.Logf("Consumed budget: $%.6f (provider limit: $%.2f)", consumedBudget, providerBudget)
				t.Logf("Last successful request cost: $%.6f", lastSuccessfulCost)

				// Verify rejection happened after exceeding the budget
				if consumedBudget < providerBudget {
					t.Fatalf("Request rejected before budget was exceeded: consumed $%.6f < limit $%.2f", consumedBudget, providerBudget)
				}

				t.Logf("Full budget hierarchy enforcement verified ✓")
				t.Logf("Request blocked at provider level (lowest in hierarchy)")
				return // Test passed
			} else {
				t.Fatalf("Request %d failed with unexpected error (not budget): %v", requestNum, resp.Body)
			}
		}

		// Request succeeded - extract actual token usage
		if usage, ok := resp.Body["usage"].(map[string]interface{}); ok {
			if prompt, ok := usage["prompt_tokens"].(float64); ok {
				if completion, ok := usage["completion_tokens"].(float64); ok {
					actualCost, _ := CalculateCost("openai/gpt-4o", int(prompt), int(completion))
					consumedBudget += actualCost
					lastSuccessfulCost = actualCost
					t.Logf("Request %d succeeded: cost=$%.6f, consumed=$%.6f/$%.2f",
						requestNum, actualCost, consumedBudget, providerBudget)
				}
			}
		}

		requestNum++

		if shouldStop {
			break
		}

		if consumedBudget >= providerBudget {
			shouldStop = true
		}
	}

	t.Fatalf("Made %d requests but never hit provider budget limit (consumed $%.6f / $%.2f) - budget not being enforced at provider level",
		requestNum-1, consumedBudget, providerBudget)
}

// ============================================================================
// CRITICAL: Failed Requests Don't Consume Budget/Rate Limits
// ============================================================================

// TestFailedRequestsDoNotConsumeBudget verifies that requests that fail
// (4xx/5xx responses) do not consume budget or rate limits
func TestFailedRequestsDoNotConsumeBudget(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create VK with small budget to easily verify consumption
	vkName := "test-vk-failed-requests-" + generateRandomID()
	budget := 0.1
	createVKResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name: vkName,
			Budget: &BudgetRequest{
				MaxLimit:      budget,
				ResetDuration: "1h",
			},
		},
	})

	if createVKResp.StatusCode != 200 {
		t.Fatalf("Failed to create VK: status %d", createVKResp.StatusCode)
	}

	vkID := ExtractIDFromResponse(t, createVKResp)
	testData.AddVirtualKey(vkID)

	vk := createVKResp.Body["virtual_key"].(map[string]interface{})
	vkValue := vk["value"].(string)

	t.Logf("Created VK with budget: $%.2f", budget)

	// Get initial budget from in-memory store
	getDataResp1 := MakeRequest(t, APIRequest{
		Method: "GET",
		Path:   "/api/governance/virtual-keys?from_memory=true",
	})

	virtualKeysMap1 := getDataResp1.Body["virtual_keys"].(map[string]interface{})

	getBudgetsResp1 := MakeRequest(t, APIRequest{
		Method: "GET",
		Path:   "/api/governance/budgets?from_memory=true",
	})

	budgetsMap1 := getBudgetsResp1.Body["budgets"].(map[string]interface{})

	vkData1 := virtualKeysMap1[vkValue].(map[string]interface{})
	budgetID, _ := vkData1["budget_id"].(string)

	budgetData1 := budgetsMap1[budgetID].(map[string]interface{})
	initialUsage, _ := budgetData1["current_usage"].(float64)

	t.Logf("Initial budget usage: $%.6f", initialUsage)

	// Make a request with invalid input that will fail
	// Using an invalid model name to force 400 error
	failResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "invalid-model-that-does-not-exist",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "This request should fail.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	t.Logf("Failed request status: %d", failResp.StatusCode)

	if failResp.StatusCode < 400 {
		t.Skip("Could not create failing request - model may be accepted")
	}

	// Wait for async PostHook goroutine to complete processing
	time.Sleep(2 * time.Second)

	// Check budget usage - should NOT have changed
	getBudgetsResp2 := MakeRequest(t, APIRequest{
		Method: "GET",
		Path:   "/api/governance/budgets?from_memory=true",
	})

	budgetsMap2 := getBudgetsResp2.Body["budgets"].(map[string]interface{})
	budgetData2 := budgetsMap2[budgetID].(map[string]interface{})
	usageAfterFailed, _ := budgetData2["current_usage"].(float64)

	t.Logf("Budget usage after failed request: $%.6f", usageAfterFailed)

	if usageAfterFailed > initialUsage+0.0001 {
		t.Fatalf("Failed request consumed budget: before=$%.6f, after=$%.6f", initialUsage, usageAfterFailed)
	}

	// Now make a successful request
	successResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "This request should succeed.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	if successResp.StatusCode != 200 {
		t.Skip("Could not make successful request")
	}

	// Wait for async PostHook goroutine to complete budget update
	time.Sleep(2 * time.Second)

	// Check budget usage - should have changed
	getBudgetsResp3 := MakeRequest(t, APIRequest{
		Method: "GET",
		Path:   "/api/governance/budgets?from_memory=true",
	})

	budgetsMap3 := getBudgetsResp3.Body["budgets"].(map[string]interface{})
	budgetData3 := budgetsMap3[budgetID].(map[string]interface{})
	usageAfterSuccess, _ := budgetData3["current_usage"].(float64)

	t.Logf("Budget usage after successful request: $%.6f", usageAfterSuccess)

	if usageAfterSuccess <= usageAfterFailed+0.0001 {
		t.Fatalf("Successful request did not consume budget: before=$%.6f, after=$%.6f", usageAfterFailed, usageAfterSuccess)
	}

	t.Logf("Failed requests do NOT consume budget ✓")
	t.Logf("Successful requests DO consume budget ✓")
}

// ============================================================================
// CRITICAL: Inactive Virtual Key Behavior
// ============================================================================

// TestInactiveVirtualKeyBlocking verifies that inactive VKs reject requests immediately
// and that reactivating VK allows requests again
func TestInactiveVirtualKeyBlocking(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create active VK
	vkName := "test-vk-inactive-" + generateRandomID()
	isActive := true
	createVKResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name:     vkName,
			IsActive: &isActive,
		},
	})

	if createVKResp.StatusCode != 200 {
		t.Fatalf("Failed to create VK: status %d", createVKResp.StatusCode)
	}

	vkID := ExtractIDFromResponse(t, createVKResp)
	testData.AddVirtualKey(vkID)

	vk := createVKResp.Body["virtual_key"].(map[string]interface{})
	vkValue := vk["value"].(string)

	t.Logf("Created VK in ACTIVE state")

	// Verify active VK works
	resp1 := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "Request with active VK should succeed.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	if resp1.StatusCode != 200 {
		t.Fatalf("Active VK request should succeed but got status %d", resp1.StatusCode)
	}

	t.Logf("Active VK request succeeded ✓")

	// Deactivate VK
	isInactive := false
	updateResp := MakeRequest(t, APIRequest{
		Method: "PUT",
		Path:   "/api/governance/virtual-keys/" + vkID,
		Body: UpdateVirtualKeyRequest{
			IsActive: &isInactive,
		},
	})

	if updateResp.StatusCode != 200 {
		t.Fatalf("Failed to deactivate VK: status %d", updateResp.StatusCode)
	}

	t.Logf("VK deactivated (isActive = false)")

	// Wait for in-memory store update
	time.Sleep(500 * time.Millisecond)

	// Verify inactive VK is blocked
	resp2 := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "Request with inactive VK should be blocked.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	if resp2.StatusCode < 400 {
		t.Fatalf("Inactive VK request should be blocked but got status %d", resp2.StatusCode)
	}

	if !CheckErrorMessage(t, resp2, "blocked") {
		t.Fatalf("Expected 'blocked' in error message but got: %v", resp2.Body)
	}

	t.Logf("Inactive VK request rejected ✓")

	// Reactivate VK
	isActiveAgain := true
	reactivateResp := MakeRequest(t, APIRequest{
		Method: "PUT",
		Path:   "/api/governance/virtual-keys/" + vkID,
		Body: UpdateVirtualKeyRequest{
			IsActive: &isActiveAgain,
		},
	})

	if reactivateResp.StatusCode != 200 {
		t.Fatalf("Failed to reactivate VK: status %d", reactivateResp.StatusCode)
	}

	t.Logf("VK reactivated (isActive = true)")

	// Wait for in-memory store update
	time.Sleep(500 * time.Millisecond)

	// Verify reactivated VK works
	resp3 := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "Request with reactivated VK should succeed.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	if resp3.StatusCode != 200 {
		t.Fatalf("Reactivated VK request should succeed but got status %d", resp3.StatusCode)
	}

	t.Logf("Reactivated VK request succeeded ✓")
	t.Logf("Inactive VK behavior verified ✓")
}

// ============================================================================
// HIGH: Rate Limit Reset Boundaries and Edge Cases
// ============================================================================

// TestRateLimitResetBoundaryConditions verifies rate limit resets at exact boundaries
func TestRateLimitResetBoundaryConditions(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create VK with short reset duration for quick testing
	vkName := "test-vk-reset-boundary-" + generateRandomID()
	requestLimit := int64(1)
	resetDuration := "15s" // Short duration for testing

	createVKResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name: vkName,
			RateLimit: &CreateRateLimitRequest{
				RequestMaxLimit:      &requestLimit,
				RequestResetDuration: &resetDuration,
			},
		},
	})

	if createVKResp.StatusCode != 200 {
		t.Fatalf("Failed to create VK: status %d", createVKResp.StatusCode)
	}

	vkID := ExtractIDFromResponse(t, createVKResp)
	testData.AddVirtualKey(vkID)

	vk := createVKResp.Body["virtual_key"].(map[string]interface{})
	vkValue := vk["value"].(string)

	t.Logf("Created VK with request limit: %d request per %s", requestLimit, resetDuration)

	// Make first request at t=0
	startTime := time.Now()
	resp1 := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "First request at t=0.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	if resp1.StatusCode != 200 {
		t.Skip("Could not make first request")
	}

	t.Logf("First request succeeded at t=0 ✓")

	// Try immediate second request - should fail
	resp2 := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "Second request before reset.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	if resp2.StatusCode < 400 {
		t.Fatalf("Second request should be rejected but got status %d", resp2.StatusCode)
	}

	t.Logf("Second request rejected (within reset window) ✓")

	// Wait for reset duration + 1 second to ensure reset happens
	waitTime := time.Until(startTime.Add(16 * time.Second))
	if waitTime > 0 {
		t.Logf("Waiting %.1f seconds for rate limit to reset...", waitTime.Seconds())
		time.Sleep(waitTime)
	}

	// After reset, third request should succeed
	resp3 := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "Third request after reset duration.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	if resp3.StatusCode != 200 {
		t.Fatalf("Third request after reset should succeed but got status %d", resp3.StatusCode)
	}

	t.Logf("Third request succeeded after reset duration ✓")
	t.Logf("Rate limit reset boundary conditions verified ✓")
}

// ============================================================================
// HIGH: Concurrent Requests to Same VK
// ============================================================================

// TestConcurrentRequestsToSameVK verifies that concurrent requests are handled safely
// and counters remain accurate under concurrent load
func TestConcurrentRequestsToSameVK(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create VK with high token limit to allow concurrent requests
	vkName := "test-vk-concurrent-" + generateRandomID()
	tokenLimit := int64(100000)
	tokenResetDuration := "1h"

	createVKResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name: vkName,
			RateLimit: &CreateRateLimitRequest{
				TokenMaxLimit:      &tokenLimit,
				TokenResetDuration: &tokenResetDuration,
			},
		},
	})

	if createVKResp.StatusCode != 200 {
		t.Fatalf("Failed to create VK: status %d", createVKResp.StatusCode)
	}

	vkID := ExtractIDFromResponse(t, createVKResp)
	testData.AddVirtualKey(vkID)

	vk := createVKResp.Body["virtual_key"].(map[string]interface{})
	vkValue := vk["value"].(string)

	t.Logf("Created VK with high token limit for concurrent testing")

	// Launch concurrent requests
	numGoroutines := 5
	requestsPerGoroutine := 3
	totalRequests := numGoroutines * requestsPerGoroutine

	var wg sync.WaitGroup
	successCount := 0
	var mu sync.Mutex

	t.Logf("Launching %d goroutines with %d requests each (total: %d requests)",
		numGoroutines, requestsPerGoroutine, totalRequests)

	for i := 0; i < numGoroutines; i++ {
		wg.Add(1)
		go func(goID int) {
			defer wg.Done()
			for j := 0; j < requestsPerGoroutine; j++ {
				resp := MakeRequest(t, APIRequest{
					Method: "POST",
					Path:   "/v1/chat/completions",
					Body: ChatCompletionRequest{
						Model: "openai/gpt-4o",
						Messages: []ChatMessage{
							{
								Role:    "user",
								Content: "Concurrent request from goroutine.",
							},
						},
					},
					VKHeader: &vkValue,
				})

				if resp.StatusCode == 200 {
					mu.Lock()
					successCount++
					mu.Unlock()
				}
			}
		}(i)
	}

	wg.Wait()

	t.Logf("Concurrent requests completed: %d successful out of %d total", successCount, totalRequests)

	if successCount == 0 {
		t.Skip("No requests succeeded - cannot test concurrent behavior")
	}

	if successCount < totalRequests/2 {
		t.Logf("Warning: Less than 50%% requests succeeded (%d/%d)", successCount, totalRequests)
	}

	t.Logf("Concurrent request handling verified ✓")
	t.Logf("No data corruption detected (test completed successfully)")
}

// ============================================================================
// HIGH: Budget State After Reset
// ============================================================================

// TestBudgetStateAfterReset verifies that budget usage is correctly reset to 0
// and LastReset timestamp is updated
func TestBudgetStateAfterReset(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create VK with short reset duration
	vkName := "test-vk-budget-reset-state-" + generateRandomID()
	budgetLimit := 1.0
	resetDuration := "15s"

	createVKResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name: vkName,
			Budget: &BudgetRequest{
				MaxLimit:      budgetLimit,
				ResetDuration: resetDuration,
			},
		},
	})

	if createVKResp.StatusCode != 200 {
		t.Fatalf("Failed to create VK: status %d", createVKResp.StatusCode)
	}

	vkID := ExtractIDFromResponse(t, createVKResp)
	testData.AddVirtualKey(vkID)

	vk := createVKResp.Body["virtual_key"].(map[string]interface{})
	vkValue := vk["value"].(string)

	t.Logf("Created VK with budget: $%.2f, reset duration: %s", budgetLimit, resetDuration)

	// Get initial budget state
	getDataResp1 := MakeRequest(t, APIRequest{
		Method: "GET",
		Path:   "/api/governance/virtual-keys?from_memory=true",
	})

	virtualKeysMap1 := getDataResp1.Body["virtual_keys"].(map[string]interface{})

	getBudgetsResp1 := MakeRequest(t, APIRequest{
		Method: "GET",
		Path:   "/api/governance/budgets?from_memory=true",
	})

	budgetsMap1 := getBudgetsResp1.Body["budgets"].(map[string]interface{})

	vkData1 := virtualKeysMap1[vkValue].(map[string]interface{})
	budgetID, _ := vkData1["budget_id"].(string)

	budgetData1 := budgetsMap1[budgetID].(map[string]interface{})
	initialUsage, _ := budgetData1["current_usage"].(float64)
	lastReset1, _ := budgetData1["last_reset"].(string)

	t.Logf("Initial budget state: usage=$%.6f, lastReset=%s", initialUsage, lastReset1)

	// Make a request to consume some budget
	resp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "Request to consume budget before reset.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	if resp.StatusCode != 200 {
		t.Skip("Could not make request to consume budget")
	}

	// Wait for async PostHook goroutine to complete budget update
	time.Sleep(2 * time.Second)

	// Check usage after request
	getBudgetsResp2 := MakeRequest(t, APIRequest{
		Method: "GET",
		Path:   "/api/governance/budgets?from_memory=true",
	})

	budgetsMap2 := getBudgetsResp2.Body["budgets"].(map[string]interface{})
	budgetData2 := budgetsMap2[budgetID].(map[string]interface{})
	usageAfterRequest, _ := budgetData2["current_usage"].(float64)

	t.Logf("Budget after request: usage=$%.6f (consumed)", usageAfterRequest)

	if usageAfterRequest <= initialUsage {
		t.Skip("Request did not consume budget")
	}

	// Wait for reset duration to pass
	// We need to wait until LastReset + resetDuration has passed
	// Parse the lastReset time to calculate the exact wait time
	lastResetTime, err := time.Parse(time.RFC3339Nano, lastReset1)
	if err != nil {
		// Fallback to RFC3339 if RFC3339Nano fails
		lastResetTime, err = time.Parse(time.RFC3339, lastReset1)
		if err != nil {
			t.Fatalf("Failed to parse lastReset time: %v", err)
		}
	}
	resetDurationParsed, err := ParseDuration(resetDuration)
	if err != nil {
		t.Fatalf("Failed to parse reset duration: %v", err)
	}

	// Calculate when reset should occur with a 2-second safety buffer
	resetTime := lastResetTime.Add(resetDurationParsed).Add(2 * time.Second)
	waitTime := time.Until(resetTime)
	if waitTime > 0 {
		t.Logf("Waiting %.1f seconds for budget to reset (lastReset was %s, reset duration is %s)...", waitTime.Seconds(), lastReset1, resetDuration)
		time.Sleep(waitTime)
	} else {
		t.Logf("No wait needed - reset duration has already passed")
	}

	// Budget resets are LAZY - they happen when:
	// 1. Background tracker runs ResetExpiredBudgets, OR
	// 2. A new request triggers UpdateBudgetUsage (which resets expired budgets inline)
	// Make another request to trigger the lazy reset mechanism
	t.Logf("Making request to trigger lazy budget reset...")
	resp2 := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "Request after reset duration to trigger lazy reset.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	if resp2.StatusCode != 200 {
		t.Logf("Post-reset request status: %d (expected 200)", resp2.StatusCode)
	}

	// Wait for async update using polling instead of fixed sleep
	// Poll for budget data to reflect the reset
	_, resetVerified := WaitForAPICondition(t, APIRequest{
		Method: "GET",
		Path:   "/api/governance/budgets?from_memory=true",
	}, func(resp *APIResponse) bool {
		if resp.StatusCode != 200 {
			return false
		}
		budgetsData, ok := resp.Body["budgets"].(map[string]interface{})
		if !ok {
			return false
		}
		budgetData, ok := budgetsData[budgetID].(map[string]interface{})
		if !ok {
			return false
		}
		// Check if LastReset has been updated (indicating reset occurred)
		newLastReset, ok := budgetData["last_reset"].(string)
		return ok && newLastReset != lastReset1
	}, 5*time.Second, "budget reset verified by timestamp")

	if !resetVerified {
		t.Logf("Warning: Reset verification polling timed out, but will proceed with final check")
	}

	// Check budget after reset
	getBudgetsResp3 := MakeRequest(t, APIRequest{
		Method: "GET",
		Path:   "/api/governance/budgets?from_memory=true",
	})

	budgetsMap3 := getBudgetsResp3.Body["budgets"].(map[string]interface{})
	budgetData3 := budgetsMap3[budgetID].(map[string]interface{})
	usageAfterReset, _ := budgetData3["current_usage"].(float64)
	lastReset3, _ := budgetData3["last_reset"].(string)

	t.Logf("Budget after reset: usage=$%.6f, lastReset=%s", usageAfterReset, lastReset3)

	// Verify the reset actually happened by checking the LastReset timestamp changed
	// This is the most reliable indicator that a reset occurred
	if lastReset3 == lastReset1 {
		t.Fatalf("Budget reset failed: LastReset timestamp was not updated (%s -> %s)", lastReset1, lastReset3)
	}
	t.Logf("✓ Budget reset verified by LastReset timestamp change")

	// Verify budget wasn't cumulative (which would indicate no reset)
	// A normal request costs $0.003-0.010
	// If it's the sum of two requests, it would be $0.008+
	// This maximum check prevents detecting cumulative usage while allowing cost variations
	if usageAfterReset > 0.012 {
		t.Logf("WARNING: Budget usage suspiciously high after reset: $%.6f (might indicate reset didn't work, but timestamp changed so reset verified)", usageAfterReset)
		t.Logf("  Before reset: $%.6f", usageAfterRequest)
		t.Logf("  After reset:  $%.6f", usageAfterReset)
		// Don't fail - could be legitimate variation in API costs
	}

	t.Logf("Budget state after reset verified ✓")
	t.Logf("Usage was reset from $%.6f to ~$%.6f (cost of one post-reset request) ✓", usageAfterRequest, usageAfterReset)
}

// ============================================================================
// HIGH: Team Deletion Cascade
// ============================================================================

// TestTeamDeletionCascade verifies that deleting a team with VKs properly cleans up
func TestTeamDeletionCascade(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create team
	teamName := "test-team-deletion-" + generateRandomID()
	createTeamResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/teams",
		Body: CreateTeamRequest{
			Name: teamName,
			Budgets: []BudgetRequest{{
				MaxLimit:      100.0,
				ResetDuration: "1h",
			}},
		},
	})

	if createTeamResp.StatusCode != 200 {
		t.Fatalf("Failed to create team: status %d", createTeamResp.StatusCode)
	}

	teamID := ExtractIDFromResponse(t, createTeamResp)
	testData.AddTeam(teamID)

	t.Logf("Created team: %s", teamID)

	// Create VK assigned to team
	vkName := "test-vk-for-team-" + generateRandomID()
	createVKResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name:   vkName,
			TeamID: &teamID,
		},
	})

	if createVKResp.StatusCode != 200 {
		t.Fatalf("Failed to create VK: status %d", createVKResp.StatusCode)
	}

	vkID := ExtractIDFromResponse(t, createVKResp)
	testData.AddVirtualKey(vkID)

	vk := createVKResp.Body["virtual_key"].(map[string]interface{})
	vkValue := vk["value"].(string)

	t.Logf("Created VK assigned to team: %s", vkID)

	// Verify VK works
	resp1 := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "Request before team deletion.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	if resp1.StatusCode != 200 {
		t.Skip("Could not verify VK before deletion")
	}

	t.Logf("VK works before team deletion ✓")

	// Delete team
	deleteResp := MakeRequest(t, APIRequest{
		Method: "DELETE",
		Path:   "/api/governance/teams/" + teamID,
	})

	if deleteResp.StatusCode != 200 {
		t.Fatalf("Failed to delete team: status %d", deleteResp.StatusCode)
	}

	t.Logf("Team deleted")

	// Wait for in-memory store update
	time.Sleep(500 * time.Millisecond)

	// Try to use VK after team deletion
	// Expected: VK should continue to work after team deletion
	// VKs can function independently without a team, but they lose access to team budget
	resp2 := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "Request after team deletion.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	// Assert VK request succeeds after team deletion
	if resp2.StatusCode != 200 {
		t.Fatalf("Expected 200 OK after team deletion (VK should continue to work), got status %d. Response: %v", resp2.StatusCode, resp2.Body)
	}

	// Assert no team budget was billed (team is deleted, so team budget should not be used)
	// The request should succeed but without team budget constraints
	// Note: We can't directly verify team budget wasn't billed from the response,
	// but we verify the request succeeds which confirms VK works independently
	t.Logf("Team deletion cascade verified ✓: VK continues to work after team deletion (without team budget)")
}

// ============================================================================
// HIGH: VK Deletion Cascade
// ============================================================================

// TestVKDeletionCascade verifies that deleting a VK properly cleans up all related resources
func TestVKDeletionCascade(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create VK with rate limit and budget
	vkName := "test-vk-deletion-" + generateRandomID()
	tokenLimit := int64(1000)
	tokenResetDuration := "1h"

	createVKResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name: vkName,
			Budget: &BudgetRequest{
				MaxLimit:      10.0,
				ResetDuration: "1h",
			},
			RateLimit: &CreateRateLimitRequest{
				TokenMaxLimit:      &tokenLimit,
				TokenResetDuration: &tokenResetDuration,
			},
		},
	})

	if createVKResp.StatusCode != 200 {
		t.Fatalf("Failed to create VK: status %d", createVKResp.StatusCode)
	}

	vkID := ExtractIDFromResponse(t, createVKResp)
	testData.AddVirtualKey(vkID)

	vk := createVKResp.Body["virtual_key"].(map[string]interface{})
	vkValue := vk["value"].(string)

	t.Logf("Created VK with rate limit and budget")

	// Verify VK exists in in-memory store (poll to ensure sync completed)
	vkExists := WaitForCondition(t, func() bool {
		getDataResp1 := MakeRequest(t, APIRequest{
			Method: "GET",
			Path:   "/api/governance/virtual-keys?from_memory=true",
		})

		if getDataResp1.StatusCode != 200 {
			return false
		}

		virtualKeysMap1, ok := getDataResp1.Body["virtual_keys"].(map[string]interface{})
		if !ok {
			return false
		}

		_, exists := virtualKeysMap1[vkValue]
		return exists
	}, 5*time.Second, "VK exists in in-memory store")

	if !vkExists {
		t.Fatalf("VK not found in in-memory store after creation (timeout after 5s)")
	}

	t.Logf("VK exists in in-memory store ✓")

	// Delete VK
	deleteResp := MakeRequest(t, APIRequest{
		Method: "DELETE",
		Path:   "/api/governance/virtual-keys/" + vkID,
	})

	if deleteResp.StatusCode != 200 {
		t.Fatalf("Failed to delete VK: status %d", deleteResp.StatusCode)
	}

	t.Logf("VK deleted from database")

	// Wait for in-memory store to sync (poll with timeout instead of fixed sleep)
	vkRemoved := WaitForCondition(t, func() bool {
		getDataResp2 := MakeRequest(t, APIRequest{
			Method: "GET",
			Path:   "/api/governance/virtual-keys?from_memory=true",
		})

		if getDataResp2.StatusCode != 200 {
			t.Logf("Failed to get VK data: status %d", getDataResp2.StatusCode)
			return false
		}

		virtualKeysMap2, ok := getDataResp2.Body["virtual_keys"].(map[string]interface{})
		if !ok {
			t.Logf("Invalid response structure for virtual_keys")
			return false
		}

		_, exists := virtualKeysMap2[vkValue]
		return !exists // Return true when VK is NOT found (successfully removed)
	}, 5*time.Second, "VK removed from in-memory store")

	if !vkRemoved {
		t.Fatalf("VK still exists in in-memory store after deletion (timeout after 5s)")
	}

	t.Logf("VK removed from in-memory store ✓")

	// Try to use deleted VK
	resp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/v1/chat/completions",
		Body: ChatCompletionRequest{
			Model: "openai/gpt-4o",
			Messages: []ChatMessage{
				{
					Role:    "user",
					Content: "Request with deleted VK should fail.",
				},
			},
		},
		VKHeader: &vkValue,
	})

	if resp.StatusCode < 400 {
		t.Logf("Deleted VK still accepts requests (status=%d) - may be cached in SDK", resp.StatusCode)
	} else {
		t.Logf("Deleted VK request rejected (status=%d) ✓", resp.StatusCode)
	}

	t.Logf("VK deletion cascade verified ✓")
}

// ============================================================================
// FEATURE: Load Balancing with Weighted Provider Distribution
// ============================================================================

// TestWeightedProviderLoadBalancing verifies that traffic is distributed between
// providers according to their weights when they share common models
func TestWeightedProviderLoadBalancing(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create VK with two providers: 99% OpenAI, 1% Azure (both support gpt-4o)
	vkName := "test-vk-weighted-lb-" + generateRandomID()
	openaiWeight := 99.0
	azureWeight := 1.0

	createVKResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name: vkName,
			ProviderConfigs: []ProviderConfigRequest{
				{
					Provider:      "openai",
					Weight:        &openaiWeight,
					AllowedModels: []string{"gpt-4o"},
					KeyIDs:        []string{"*"},
				},
				{
					Provider:      "azure",
					Weight:        &azureWeight,
					AllowedModels: []string{"gpt-4o"},
					KeyIDs:        []string{"*"},
				},
			},
		},
	})

	if createVKResp.StatusCode != 200 {
		t.Fatalf("Failed to create VK: status %d", createVKResp.StatusCode)
	}

	vkID := ExtractIDFromResponse(t, createVKResp)
	testData.AddVirtualKey(vkID)

	vk := createVKResp.Body["virtual_key"].(map[string]interface{})
	vkValue := vk["value"].(string)

	t.Logf("Created VK with weighted providers: OpenAI(%.0f%%), Azure(%.0f%%)", openaiWeight, azureWeight)

	// Verify both providers are configured
	getDataResp := MakeRequest(t, APIRequest{
		Method: "GET",
		Path:   "/api/governance/virtual-keys?from_memory=true",
	})

	virtualKeysMap := getDataResp.Body["virtual_keys"].(map[string]interface{})
	vkData := virtualKeysMap[vkValue].(map[string]interface{})
	providerConfigs, _ := vkData["provider_configs"].([]interface{})

	if len(providerConfigs) != 2 {
		t.Fatalf("Expected 2 provider configs, got %d", len(providerConfigs))
	}

	t.Logf("Both provider configs present in in-memory store ✓")

	// Make 10 requests with just "gpt-4o" (no provider prefix)
	// Expected: ~99 go to OpenAI, ~1 go to Azure
	numRequests := 10
	openaiCount := 0
	azureCount := 0
	failureCount := 0

	t.Logf("Making %d weighted requests with model: 'gpt-4o' (no provider prefix)...", numRequests)

	for i := 0; i < numRequests; i++ {
		resp := MakeRequest(t, APIRequest{
			Method: "POST",
			Path:   "/v1/chat/completions",
			Body: ChatCompletionRequest{
				Model: "gpt-4o", // No provider prefix - should be routed based on weights
				Messages: []ChatMessage{
					{
						Role:    "user",
						Content: "Hello how are you?",
					},
				},
			},
			VKHeader: &vkValue,
		})

		if resp.StatusCode != 200 {
			failureCount++
			t.Logf("Request %d failed with status %d", i+1, resp.StatusCode)
			continue
		}

		// Try to detect which provider was used
		// Check if model in response contains provider name
		if provider, ok := resp.Body["extra_fields"].(map[string]interface{})["provider"].(string); ok {
			model, ok := resp.Body["extra_fields"].(map[string]interface{})["original_model_requested"].(string)
			if !ok {
				t.Logf("Request %d failed to get model requested", i+1)
				continue
			}
			if provider == "openai" {
				openaiCount++
				t.Logf("Request %d routed to OpenAI (model: %s)", i+1, model)
			} else if provider == "azure" {
				azureCount++
				t.Logf("Request %d routed to Azure (model: %s)", i+1, model)
			}
		}
	}

	totalSuccess := openaiCount + azureCount
	t.Logf("Results: OpenAI=%d, Azure=%d, Failed=%d (total requests=%d)",
		openaiCount, azureCount, failureCount, numRequests)

	if totalSuccess == 0 {
		t.Skip("No successful requests to analyze distribution")
	}

	// With 99% weight to OpenAI and 1% to Azure:
	// Out of 10 requests, we expect ~0-2 to go to Azure (1%)
	if azureCount > 2 {
		t.Logf("Warning: More requests went to Azure than expected (got %d, expected ~0-2)", azureCount)
	}

	t.Logf("Weighted provider load balancing verified ✓")
	t.Logf("Traffic distribution approximately matches configured weights")
}

// ============================================================================
// FEATURE: Fallback Provider Mechanism
// ============================================================================

// TestProviderFallbackMechanism verifies that when primary provider doesn't support
// a model, fallback providers are used automatically
func TestProviderFallbackMechanism(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create VK with two providers:
	// - 99% Anthropic (does NOT support gpt-4o)
	// - 1% OpenAI (DOES support gpt-4o)
	// When requesting gpt-4o, it should fall back to OpenAI since Anthropic doesn't have it
	vkName := "test-vk-fallback-" + generateRandomID()
	anthropicWeight := 99.0
	openaiWeight := 1.0

	createVKResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name: vkName,
			ProviderConfigs: []ProviderConfigRequest{
				{
					Provider:      "anthropic",
					Weight:        &anthropicWeight,
					AllowedModels: []string{"claude-3-sonnet"}, // Does NOT include gpt-4o
					KeyIDs:        []string{"*"},
				},
				{
					Provider:      "openai",
					Weight:        &openaiWeight,
					AllowedModels: []string{"gpt-4o"}, // DOES include gpt-4o
					KeyIDs:        []string{"*"},
				},
			},
		},
	})

	if createVKResp.StatusCode != 200 {
		t.Fatalf("Failed to create VK: status %d", createVKResp.StatusCode)
	}

	vkID := ExtractIDFromResponse(t, createVKResp)
	testData.AddVirtualKey(vkID)

	vk := createVKResp.Body["virtual_key"].(map[string]interface{})
	vkValue := vk["value"].(string)

	t.Logf("Created VK with providers: Anthropic(99%%, no gpt-4o), OpenAI(1%%, supports gpt-4o)")

	// Make 5 requests for gpt-4o model
	// Even though Anthropic has 99% weight, all should succeed via OpenAI fallback
	numRequests := 5
	successCount := 0

	t.Logf("Making %d requests with model: 'gpt-4o' (not supported by primary provider)...", numRequests)

	for i := 0; i < numRequests; i++ {
		resp := MakeRequest(t, APIRequest{
			Method: "POST",
			Path:   "/v1/chat/completions",
			Body: ChatCompletionRequest{
				Model: "gpt-4o", // Only OpenAI supports this
				Messages: []ChatMessage{
					{
						Role:    "user",
						Content: "Hello how are you?",
					},
				},
			},
			VKHeader: &vkValue,
		})

		if resp.StatusCode == 200 {
			successCount++

			// Try to detect which provider actually handled it
			model := ""
			if m, ok := resp.Body["model"].(string); ok {
				model = m
			}

			t.Logf("Request %d succeeded (model: %s) - likely via OpenAI fallback", i+1, model)
		} else {
			t.Logf("Request %d failed with status %d", i+1, resp.StatusCode)
		}
	}

	t.Logf("Results: %d/%d requests succeeded via fallback", successCount, numRequests)

	if successCount == 0 {
		t.Skip("No successful requests - cannot verify fallback mechanism")
	}

	if successCount < numRequests {
		t.Logf("Warning: Not all requests succeeded (got %d/%d)", successCount, numRequests)
	} else {
		t.Logf("All requests succeeded via fallback provider ✓")
	}

	t.Logf("Fallback provider mechanism verified ✓")
	t.Logf("Requests successfully routed to fallback when primary doesn't support model")
}

// ============================================================================
// Virtual Key Header Formats
// ============================================================================

// TestVirtualKeyHeaderFormats verifies that Bifrost accepts all documented VK header formats
// Reference: https://docs.getbifrost.ai/features/governance/virtual-keys
// Supported headers:
//   - x-bf-vk: Virtual key header (Bifrost native)
//   - Authorization: Bearer token style (OpenAI style)
//   - x-api-key: API key header (Anthropic style)
//   - x-goog-api-key: API key header (Google Gemini style)
func TestVirtualKeyHeaderFormats(t *testing.T) {
	t.Parallel()
	testData := NewGlobalTestData()
	defer testData.Cleanup(t)

	// Create a VK with minimal config to test header acceptance
	vkName := "test-vk-headers-" + generateRandomID()
	createVKResp := MakeRequest(t, APIRequest{
		Method: "POST",
		Path:   "/api/governance/virtual-keys",
		Body: CreateVirtualKeyRequest{
			Name: vkName,
			Budget: &BudgetRequest{
				MaxLimit:      10.0,
				ResetDuration: "1h",
			},
		},
	})

	if createVKResp.StatusCode != 200 {
		t.Fatalf("Failed to create VK: status %d", createVKResp.StatusCode)
	}

	vkID := ExtractIDFromResponse(t, createVKResp)
	testData.AddVirtualKey(vkID)

	vk := createVKResp.Body["virtual_key"].(map[string]interface{})
	vkValue := vk["value"].(string)

	t.Logf("Created VK for header format testing: %s", vkValue)

	// Test all supported header formats
	testCases := []struct {
		name         string
		headerName   string
		headerValue  string
		description  string
		expectedPass bool
	}{
		{
			name:         "x-bf-vk header",
			headerName:   "x-bf-vk",
			headerValue:  vkValue,
			description:  "Bifrost native VK header",
			expectedPass: true,
		},
		{
			name:         "Authorization Bearer",
			headerName:   "Authorization",
			headerValue:  "Bearer " + vkValue,
			description:  "OpenAI-style Bearer token",
			expectedPass: true,
		},
		{
			name:         "x-api-key",
			headerName:   "x-api-key",
			headerValue:  vkValue,
			description:  "Anthropic-style API key",
			expectedPass: true,
		},
		{
			name:         "x-goog-api-key",
			headerName:   "x-goog-api-key",
			headerValue:  vkValue,
			description:  "Google Gemini-style API key",
			expectedPass: true,
		},
	}

	for _, tc := range testCases {
		t.Run(tc.name, func(t *testing.T) {
			// Make request with the specific header format
			resp := MakeRequestWithCustomHeaders(t, APIRequest{
				Method: "POST",
				Path:   "/v1/chat/completions",
				Body: ChatCompletionRequest{
					Model: "openai/gpt-4o-mini",
					Messages: []ChatMessage{
						{
							Role:    "user",
							Content: "Test request for header format: " + tc.name,
						},
					},
				},
			}, map[string]string{
				tc.headerName: tc.headerValue,
			})

			if tc.expectedPass {
				if resp.StatusCode != 200 {
					t.Errorf("Expected %s to work, but got status %d (response: %v)", tc.description, resp.StatusCode, resp.Body)
				} else {
					t.Logf("✓ %s works correctly (status: %d)", tc.description, resp.StatusCode)
				}
			} else {
				if resp.StatusCode == 200 {
					t.Errorf("Expected %s to fail, but got status 200", tc.description)
				} else {
					t.Logf("✓ %s correctly rejected (status: %d)", tc.description, resp.StatusCode)
				}
			}
		})
	}

	t.Logf("All virtual key header formats verified ✓")
}