package de.cannamanage.api.security;

import lombok.RequiredArgsConstructor;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.annotation.Order;
import org.springframework.http.HttpMethod;
import org.springframework.security.config.annotation.method.configuration.EnableMethodSecurity;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.http.SessionCreationPolicy;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;
import org.springframework.security.web.SecurityFilterChain;
import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
import org.springframework.security.web.csrf.CookieCsrfTokenRepository;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.CorsConfigurationSource;
import org.springframework.web.cors.UrlBasedCorsConfigurationSource;

import jakarta.servlet.http.HttpServletResponse;
import java.util.Arrays;
import java.util.List;

/**
 * Security configuration — Sprint 3: API + Staff portal with JWT + Member portal with sessions.
 * Roles: ADMIN (full access) + STAFF (permission-based) + MEMBER (self-service portal).
 */
@Configuration
@EnableWebSecurity
@EnableMethodSecurity
@RequiredArgsConstructor
public class SecurityConfig {

    private final JwtAuthFilter jwtAuthFilter;
    private final PortalUserDetailsService portalUserDetailsService;

    /**
     * Comma-separated allowed CORS origins. Defaults to local dev origins; production
     * deployments override via the {@code CORS_ORIGINS} environment variable
     * (e.g. {@code https://cannamanage.plate-software.de}).
     */
    @Value("${cannamanage.cors.allowed-origins:http://localhost:3000,http://frontend:3000}")
    private String allowedOrigins;

    /**
     * API security — stateless JWT authentication.
     * URL-level role checks provide first layer; @PreAuthorize provides fine-grained.
     */
    @Bean
    @Order(1)
    public SecurityFilterChain apiSecurityFilterChain(HttpSecurity http) throws Exception {
        http
                .securityMatcher("/api/**")
                .cors(cors -> cors.configurationSource(corsConfigurationSource()))
                // snyk:ignore java/CsrfProtectionDisabled — Intentional: this filter chain
                // handles stateless JWT-authenticated API calls only. CSRF attacks exploit
                // browser-managed session cookies; Bearer token auth is immune because the
                // token is never sent automatically by the browser. OWASP CSRF Prevention
                // Cheat Sheet: "If your application does not use cookies for authentication,
                // CSRF is not a risk." The portal chain (Order 2) correctly enables CSRF via
                // CookieCsrfTokenRepository for its session-based auth.
                .csrf(csrf -> csrf.disable())
                .sessionManagement(session -> session
                        .sessionCreationPolicy(SessionCreationPolicy.STATELESS))
                .headers(headers -> headers
                        .contentSecurityPolicy(csp -> csp.policyDirectives(
                                "default-src 'self'; frame-ancestors 'none'"))
                        .frameOptions(frame -> frame.deny()))
                .authorizeHttpRequests(auth -> auth
                        .requestMatchers("/api/v1/auth/**").permitAll()
                        .requestMatchers("/api/v1/webhooks/**").permitAll()
                        .requestMatchers("/api/v1/billing/**").hasRole("ADMIN")
                        .requestMatchers("/api/v1/admin/**").hasRole("ADMIN")
                        .requestMatchers("/api/v1/staff/**").hasRole("ADMIN")
                        .requestMatchers("/api/v1/members/**").hasAnyRole("ADMIN", "STAFF", "MEMBER")
                        .requestMatchers("/api/v1/distributions/**").hasAnyRole("ADMIN", "STAFF", "MEMBER")
                        .requestMatchers("/api/v1/stock/**").hasAnyRole("ADMIN", "STAFF")
                        .requestMatchers("/api/v1/compliance/**").hasAnyRole("ADMIN", "STAFF", "MEMBER")
                        .requestMatchers("/api/v1/reports/**").hasRole("ADMIN")
                        // Documents endpoint — method-specific matchers for defense-in-depth.
                        // POST (upload) and DELETE restricted to ADMIN/STAFF; GET allowed for all
                        // authenticated roles. Per-document tenant ownership is additionally
                        // enforced in DocumentController via TenantContext.
                        .requestMatchers(HttpMethod.GET, "/api/v1/documents/**").hasAnyRole("ADMIN", "STAFF", "MEMBER")
                        .requestMatchers(HttpMethod.POST, "/api/v1/documents/**").hasAnyRole("ADMIN", "STAFF")
                        .requestMatchers(HttpMethod.DELETE, "/api/v1/documents/**").hasAnyRole("ADMIN", "STAFF")
                        .anyRequest().authenticated())
                .addFilterBefore(jwtAuthFilter, UsernamePasswordAuthenticationFilter.class);

        return http.build();
    }

    /**
     * Member portal — session-based authentication with CSRF protection.
     * React SPA consumes JSON responses; custom success/failure handlers return JSON (not redirects).
     */
    @Bean
    @Order(2)
    public SecurityFilterChain portalSecurityFilterChain(HttpSecurity http) throws Exception {
        http
                .securityMatcher("/portal/**")
                .csrf(csrf -> csrf
                        .csrfTokenRepository(CookieCsrfTokenRepository.withHttpOnlyFalse()))
                .sessionManagement(session -> session
                        .sessionCreationPolicy(SessionCreationPolicy.IF_REQUIRED)
                        .maximumSessions(1))
                .headers(headers -> headers
                        .contentSecurityPolicy(csp -> csp.policyDirectives(
                                "default-src 'self'; frame-ancestors 'none'"))
                        .frameOptions(frame -> frame.deny()))
                .userDetailsService(portalUserDetailsService)
                .formLogin(form -> form
                        .loginProcessingUrl("/portal/login")
                        .successHandler((request, response, authentication) -> {
                            response.setContentType("application/json");
                            response.setStatus(HttpServletResponse.SC_OK);
                            response.getWriter().write("{\"status\":\"ok\"}");
                        })
                        .failureHandler((request, response, exception) -> {
                            response.setContentType("application/json");
                            response.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
                            response.getWriter().write("{\"error\":\"Invalid credentials\"}");
                        })
                        .permitAll())
                .logout(logout -> logout
                        .logoutUrl("/portal/logout")
                        .logoutSuccessHandler((request, response, authentication) -> {
                            response.setContentType("application/json");
                            response.setStatus(HttpServletResponse.SC_OK);
                            response.getWriter().write("{\"status\":\"logged_out\"}");
                        }))
                .authorizeHttpRequests(auth -> auth
                        .requestMatchers("/portal/login", "/portal/css/**", "/portal/js/**").permitAll()
                        .requestMatchers("/portal/**").hasRole("MEMBER"));

        return http.build();
    }

    /**
     * Public endpoints — Swagger UI, actuator health.
     */
    @Bean
    @Order(3)
    public SecurityFilterChain publicSecurityFilterChain(HttpSecurity http) throws Exception {
        http
                .securityMatcher("/swagger-ui/**", "/v3/api-docs/**", "/actuator/health")
                .csrf(csrf -> csrf.disable())
                .authorizeHttpRequests(auth -> auth.anyRequest().permitAll());

        return http.build();
    }

    @Bean
    public PasswordEncoder passwordEncoder() {
        return new BCryptPasswordEncoder();
    }

    @Bean
    public CorsConfigurationSource corsConfigurationSource() {
        CorsConfiguration config = new CorsConfiguration();
        List<String> origins = Arrays.stream(allowedOrigins.split(","))
                .map(String::trim)
                .filter(s -> !s.isEmpty())
                .toList();
        config.setAllowedOrigins(origins);
        config.setAllowedMethods(List.of("GET", "POST", "PUT", "DELETE", "PATCH", "OPTIONS"));
        config.setAllowedHeaders(List.of("*"));
        config.setAllowCredentials(true);
        config.setMaxAge(3600L);

        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        source.registerCorsConfiguration("/api/**", config);
        return source;
    }
}