//go:build test

package main

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

	"crussell/db"
)

func TestHealthCheck_OK(t *testing.T) {

	// Create request and recorder
	req := httptest.NewRequest(http.MethodGet, "/api/health", nil)
	w := httptest.NewRecorder()

	// Call handler directly
	healthCheckHandler(w, req)

	// Assert 200 OK
	if w.Code != http.StatusOK {
		t.Errorf("expected status %d, got %d. body: %s", http.StatusOK, w.Code, w.Body.String())
	}

	// Parse JSON response
	var response map[string]interface{}
	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
		t.Fatalf("failed to parse JSON response: %v", err)
	}

	// Assert status == "ok"
	status, ok := response["status"].(string)
	if !ok || status != "ok" {
		t.Errorf("expected status 'ok', got '%v'", response["status"])
	}

	// Assert services
	services, ok := response["services"].(map[string]interface{})
	if !ok {
		t.Fatalf("services not found in response")
	}

	// Assert services.backend == "ok"
	backend, ok := services["backend"].(string)
	if !ok || backend != "ok" {
		t.Errorf("expected services.backend 'ok', got '%v'", services["backend"])
	}

	// Assert services.database == "ok"
	database, ok := services["database"].(string)
	if !ok || database != "ok" {
		t.Errorf("expected services.database 'ok', got '%v'", services["database"])
	}
}

func TestHealthCheck_Degraded(t *testing.T) {

	// Set db.Conn to nil to simulate degraded state
	originalDB := db.Conn
	db.Conn = nil

	// Create request and recorder
	req := httptest.NewRequest(http.MethodGet, "/api/health", nil)
	w := httptest.NewRecorder()

	// Call handler directly
	healthCheckHandler(w, req)

	// Assert 503 Service Unavailable
	if w.Code != http.StatusServiceUnavailable {
		t.Errorf("expected status %d, got %d. body: %s", http.StatusServiceUnavailable, w.Code, w.Body.String())
	}

	// Parse JSON response
	var response map[string]interface{}
	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
		t.Fatalf("failed to parse JSON response: %v", err)
	}

	// Assert status == "degraded"
	status, ok := response["status"].(string)
	if !ok || status != "degraded" {
		t.Errorf("expected status 'degraded', got '%v'", response["status"])
	}

	// Assert services
	services, ok := response["services"].(map[string]interface{})
	if !ok {
		t.Fatalf("services not found in response")
	}

	// Assert services.database == "error"
	database, ok := services["database"].(string)
	if !ok || database != "error" {
		t.Errorf("expected services.database 'error', got '%v'", services["database"])
	}

	// Restore original db.Conn
	db.Conn = originalDB
}

func TestCORS_OnlyAllowedOrigins(t *testing.T) {
	t.Setenv("FRONTEND_ORIGIN", "https://app.example.com, http://localhost:5173")
	handler := corsMiddleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	tests := []struct {
		name          string
		origin        string
		expectAllowed bool
	}{
		{name: "first configured origin is allowed", origin: "https://app.example.com", expectAllowed: true},
		{name: "second configured origin is allowed", origin: "http://localhost:5173", expectAllowed: true},
		{name: "unlisted origin is rejected", origin: "https://evil.example.com", expectAllowed: false},
		{name: "prefix-confusion origin is rejected", origin: "https://app.example.com.evil.test", expectAllowed: false},
		{name: "suffix-attack origin is rejected", origin: "https://app.example.com/evil", expectAllowed: false},
		{name: "no origin header is not echoed", origin: "", expectAllowed: false},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			req := httptest.NewRequest(http.MethodGet, "/api/health", nil)
			if tt.origin != "" {
				req.Header.Set("Origin", tt.origin)
			}
			rr := httptest.NewRecorder()
			handler.ServeHTTP(rr, req)

			got := rr.Header().Get("Access-Control-Allow-Origin")
			if tt.expectAllowed && got != tt.origin {
				t.Errorf("expected Access-Control-Allow-Origin %q, got %q", tt.origin, got)
			}
			if !tt.expectAllowed && got != "" {
				t.Errorf("expected no Access-Control-Allow-Origin header, got %q", got)
			}
		})
	}
}

func TestCORS_DefaultOriginWhenEnvUnset(t *testing.T) {
	t.Setenv("FRONTEND_ORIGIN", "")
	handler := corsMiddleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	allowed := httptest.NewRequest(http.MethodGet, "/", nil)
	allowed.Header.Set("Origin", "http://localhost:5173")
	aw := httptest.NewRecorder()
	handler.ServeHTTP(aw, allowed)
	if got := aw.Header().Get("Access-Control-Allow-Origin"); got != "http://localhost:5173" {
		t.Errorf("expected default dev origin to be allowed, got %q", got)
	}

	evil := httptest.NewRequest(http.MethodGet, "/", nil)
	evil.Header.Set("Origin", "https://evil.example.com")
	ew := httptest.NewRecorder()
	handler.ServeHTTP(ew, evil)
	if got := ew.Header().Get("Access-Control-Allow-Origin"); got != "" {
		t.Errorf("expected unlisted origin to be rejected with default config, got %q", got)
	}
}

func TestCORSPreflight_RejectsUnlistedOrigin(t *testing.T) {
	t.Setenv("FRONTEND_ORIGIN", "https://app.example.com")
	handler := corsMiddleware(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodOptions, "/api/bookings", nil)
	req.Header.Set("Origin", "https://evil.example.com")
	req.Header.Set("Access-Control-Request-Method", "POST")
	rr := httptest.NewRecorder()
	handler.ServeHTTP(rr, req)

	if rr.Code != http.StatusNoContent {
		t.Errorf("expected preflight 204, got %d", rr.Code)
	}
	if got := rr.Header().Get("Access-Control-Allow-Origin"); got != "" {
		t.Errorf("expected no Access-Control-Allow-Origin on preflight for unlisted origin, got %q", got)
	}
}

// ============================================================
// isWeakJWTSecret — fail-closed JWT signing-key guard (batch-1 fix)
// ============================================================

// TestIsWeakJWTSecret_WeakSecrets verifies known placeholder/example values
// (publicly documented in .env.example, READMEs, or attack tooling) are always
// rejected even when they clear the 32-character minimum.
func TestIsWeakJWTSecret_WeakSecrets(t *testing.T) {
	weak := []string{
		"password",
		"secret",
		"changeme",
		"change-me",
		"changethis",
		"CHANGE_ME",
		"your-secret-key",
		"your-secret",
		"jwt-secret",
		"jwt-secret-key",
		"default-secret",
		"my-secret",
		"test-secret",
		"test-secret-key",
		"super-secret",
		"a-very-secret-key-that-should-be-in-env", // 39 chars — length passes, list blocks
		"test-secret-key-for-testing-only",        // 32 chars — length passes, list blocks
	}
	for _, s := range weak {
		if !isWeakJWTSecret(s) {
			t.Errorf("expected known weak secret %q to be rejected", s)
		}
	}
}

// TestIsWeakJWTSecret_ShortSecrets verifies anything under 32 bytes is weak:
// HS256 keys must be at least 256 bits to be meaningful.
func TestIsWeakJWTSecret_ShortSecrets(t *testing.T) {
	short := []string{
		"",
		"a",
		"short",
		"0123456789",
		"0123456789012345678901234567890", // 31 chars < 32
	}
	for _, s := range short {
		if !isWeakJWTSecret(s) {
			t.Errorf("expected %q (%d chars) to be weak", s, len(s))
		}
	}
}

// TestIsWeakJWTSecret_StrongRandomSecret verifies a strong random 32+ byte
// secret (not a known placeholder) is accepted.
func TestIsWeakJWTSecret_StrongRandomSecret(t *testing.T) {
	strong := "b8f0c2a1d3e4f5a6b7c8d9e0f1a2b3c4d5e6f7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2"
	if isWeakJWTSecret(strong) {
		t.Errorf("expected a strong 50-char random secret to be accepted")
	}
	exactly32 := "9f2kL7mP4qR8sT1uV5wX3yZ6aB0cD2eG" // exactly 32 chars
	if isWeakJWTSecret(exactly32) {
		t.Errorf("expected an exactly-32-char random secret to be accepted")
	}
}

// TestIsWeakJWTSecret_CaseAndWhitespaceInsensitive verifies the check lowercases
// and trims before comparing, so padded/case-varied placeholders cannot slip
// through.
func TestIsWeakJWTSecret_CaseAndWhitespaceInsensitive(t *testing.T) {
	for _, s := range []string{"PASSWORD", " SeCrEt ", "\tchangeme\n", "  super-secret  "} {
		if !isWeakJWTSecret(s) {
			t.Errorf("expected %q to be weak after case/whitespace normalisation", s)
		}
	}
	paddedStrong := "  xY9Q2mR7vB4nK8wP1tL5sD3fG6hJ0cVnW4  "
	if isWeakJWTSecret(paddedStrong) {
		t.Errorf("expected a whitespace-padded strong secret to be accepted")
	}
}

// ============================================================
// isWeakJWTSecret entropy gate (B15)
// ============================================================

// TestIsWeakJWTSecret_EntropyGate verifies the B15 fix: secrets that clear the
// length and blacklist checks but lack entropy are rejected. An all-same-char
// and an all-zero 32+ char secret each have a 1-byte alphabet — trivially
// brute-forceable despite meeting the length requirement — while a strong
// random secret with many distinct bytes is accepted.
func TestIsWeakJWTSecret_EntropyGate(t *testing.T) {
	weak := []string{
		strings.Repeat("a", 32),            // all-same-char: 1 distinct byte
		strings.Repeat("0", 32),            // all-zero: 1 distinct byte
		strings.Repeat("ab", 16),           // 2 distinct bytes
		strings.Repeat("abcd", 8),          // 4 distinct bytes
		"abcdefghijklmnopqrstuvwxyz123456", // many distinct, strong — accepted
	}
	for i := 0; i < len(weak)-1; i++ {
		if !isWeakJWTSecret(weak[i]) {
			t.Errorf("expected low-entropy secret %q to be rejected", weak[i])
		}
	}
	if isWeakJWTSecret(weak[len(weak)-1]) {
		t.Errorf("expected high-entropy secret %q to be accepted", weak[len(weak)-1])
	}
}