package middleware

import (
	"net/http"
	"strings"

	"git.nakama.town/fmartingr/hako/internal/auth"
	"git.nakama.town/fmartingr/hako/internal/auth/store"
	"git.nakama.town/fmartingr/hako/internal/server/webcontext"
	"github.com/google/uuid"
)

// AuthMiddleware is a global middleware that validates JWT tokens if present
// and adds user info to context. It does not block requests if no token is provided.
// This allows routes to optionally use authentication information.
// The middleware also verifies that the user exists in the database to prevent
// authentication with tokens for deleted users.
func AuthMiddleware(jwtService *auth.JWTService, userStore *store.UserStore) func(http.Handler) http.Handler {
	return func(next http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			// Create webcontext for this request
			c := webcontext.NewWebContext(w, r)

			var tokenString string

			// Extract token from Authorization header if present
			authHeader := r.Header.Get("Authorization")
			if authHeader != "" {
				// Check Bearer prefix
				parts := strings.Split(authHeader, " ")
				if len(parts) == 2 && parts[0] == "Bearer" {
					tokenString = parts[1]
				}
			}

			// Fallback: extract token from query parameter if not in header
			// This allows embedding authenticated URLs (e.g., for images)
			if tokenString == "" {
				tokenString = r.URL.Query().Get("token")
			}

			// Validate token if present
			if tokenString != "" {
				// Validate token - if valid, verify user exists; if invalid, continue without context
				claims, err := jwtService.ValidateToken(tokenString)
				if err == nil {
					// Token is valid, verify user exists in database
					userID, parseErr := uuid.Parse(claims.UserID)
					if parseErr == nil {
						user, userErr := userStore.FindByID(userID)
						if userErr == nil && user != nil {
							// User exists, add user info to context
							// Use role from database (source of truth)
							role := user.Role
							if role == "" {
								role = "user"
							}
							c.SetUserWithRole(claims.UserID, claims.Email, role)
							// Update request with new context
							r = c.Request()
						}
						// If user doesn't exist, continue without setting context (don't block)
					}
				}
				// If token is invalid, continue without setting context (don't block)
			}

			// Continue with request (with or without user context)
			// Use the updated request if context was modified
			next.ServeHTTP(w, r)
		})
	}
}

// RequireAuthMiddleware is a middleware that requires authentication.
// It checks if user info is in context and returns 401 if not authenticated.
func RequireAuthMiddleware() func(http.Handler) http.Handler {
	return func(next http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			// Create webcontext for this request
			c := webcontext.NewWebContext(w, r)

			// Check if user is authenticated
			if !c.UserIsLogged() {
				http.Error(w, "Authorization required", http.StatusUnauthorized)
				return
			}

			// User is authenticated, continue
			next.ServeHTTP(w, r)
		})
	}
}

// RequireAdminMiddleware is a middleware that requires admin role.
// It checks if user is authenticated and has admin role, returns 403 if not admin.
func RequireAdminMiddleware() func(http.Handler) http.Handler {
	return func(next http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			// Create webcontext for this request
			c := webcontext.NewWebContext(w, r)

			// Check if user is authenticated
			if !c.UserIsLogged() {
				http.Error(w, "Authorization required", http.StatusUnauthorized)
				return
			}

			// Check if user has admin role
			role := c.GetUserRole()
			if role != "admin" {
				http.Error(w, "Admin access required", http.StatusForbidden)
				return
			}

			// User is authenticated and is admin, continue
			next.ServeHTTP(w, r)
		})
	}
}