upstream sapl_server {
    server unix:/var/interlegis/sapl/run/gunicorn.sock fail_timeout=0;
}

# Reuse X-Request-ID from ingress if present; otherwise generate one.
map $http_x_request_id $req_id {
    default $http_x_request_id;
    ""      $request_id;
}


server {

    listen   80;
    server_name sapl.prod;

    client_max_body_size 4G;

    # ----------------------------------------------------------------
    # Block known scraper ASNs (datacenter traffic) — zero Python cost.
    # ----------------------------------------------------------------
    if ($bot_asn = 1) {
        return 429 "Too Many Requests";
    }

    # ----------------------------------------------------------------
    # Block known bots by User-Agent — zero Python cost.
    # ----------------------------------------------------------------
    if ($bot_ua_blocked = 1) {
        return 429 "Too Many Requests";
    }

    # ----------------------------------------------------------------
    # robots.txt served directly by nginx.
    # ----------------------------------------------------------------
    location = /robots.txt {
        alias /var/interlegis/sapl/collected_static/robots.txt;
    }

    # ----------------------------------------------------------------
    # Static files — no rate limiting, no proxy.
    # ----------------------------------------------------------------
    location /static/ {
        alias /var/interlegis/sapl/collected_static/;
        expires 90m;
        add_header Cache-Control "public, max-age=5400";
    }

    # ----------------------------------------------------------------
    # Media files — routed through Django for auth, rate counting,
    # and content-type caching; served from disk via X-Accel-Redirect.
    # ----------------------------------------------------------------
    location /media/ {
        limit_req zone=sapl_general burst=${NGINX_BURST_GENERAL} nodelay;
        limit_req_status 429;

        proxy_set_header X-Request-ID      $req_id;
        proxy_set_header X-Forwarded-For   $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Host              $http_host;
        proxy_redirect off;
        proxy_pass http://sapl_server;
    }

    # Internal location used exclusively by X-Accel-Redirect responses
    # from serve_media().  Not reachable by external clients.
    location /internal/media/ {
        internal;
        alias /var/interlegis/sapl/media/;
        sendfile on;
        etag on;
    }

    # ----------------------------------------------------------------
    # /relatorios/ — heaviest endpoint (PDF generation).
    # Tighter rate limit; extended timeout for uncached generation.
    # ----------------------------------------------------------------
    location /relatorios/ {
        limit_req zone=sapl_heavy burst=${NGINX_BURST_HEAVY} nodelay;
        limit_req_status 429;

        proxy_read_timeout  180s;
        proxy_send_timeout  180s;

        proxy_set_header X-Request-ID      $req_id;
        proxy_set_header X-Forwarded-For   $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Host              $http_host;
        proxy_redirect off;
        proxy_pass http://sapl_server;
    }

    # ----------------------------------------------------------------
    # /api/ — rate limited, CORS maintained from original config.
    # ----------------------------------------------------------------
    location /api/ {
        limit_req zone=sapl_general burst=${NGINX_BURST_API} nodelay;
        limit_req_status 429;

        add_header 'Access-Control-Allow-Origin' '*';
        add_header 'Access-Control-Allow-Credentials' 'true';
        add_header 'Access-Control-Allow-Methods' 'GET, POST, PUT, DELETE, HEAD, OPTIONS';
        add_header 'Access-Control-Allow-Headers' 'Access-Control-Allow-Origin,XMLHttpRequest,Accept,Authorization,Cache-Control,Content-Type,DNT,If-Modified-Since,Keep-Alive,Origin,User-Agent,X-Mx-ReqToken,X-Requested-With';
        add_header 'Access-Control-Expose-Headers' 'Access-Control-Allow-Origin,XMLHttpRequest,Accept,Authorization,Cache-Control,Content-Type,DNT,If-Modified-Since,Keep-Alive,Origin,User-Agent,X-Mx-ReqToken,X-Requested-With';

        if ($request_method = 'OPTIONS') {
            add_header 'Access-Control-Allow-Origin' '*';
            add_header 'Access-Control-Allow-Methods' 'GET, POST, PUT, DELETE, HEAD, OPTIONS';
            add_header 'Access-Control-Allow-Headers' 'Authorization,Accept,DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range';
            add_header 'Access-Control-Expose-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range';
            add_header 'Access-Control-Max-Age' 1728000;
            add_header 'Content-Type' 'text/plain; charset=utf-8';
            add_header 'Content-Length' 0;
            return 204;
        }

        proxy_set_header X-Request-ID      $req_id;
        proxy_set_header X-Forwarded-For   $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Host              $http_host;
        proxy_redirect off;
        proxy_pass http://sapl_server;
    }

    # ----------------------------------------------------------------
    # General traffic — moderate rate limit.
    # ----------------------------------------------------------------
    location / {
        limit_req zone=sapl_general burst=${NGINX_BURST_GENERAL} nodelay;
        limit_req_status 429;

        proxy_set_header X-Request-ID      $req_id;
        proxy_set_header X-Forwarded-For   $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Host              $http_host;
        proxy_redirect off;
        proxy_pass http://sapl_server;
    }

    error_page 429 /429.html;
    location = /429.html {
        add_header Retry-After 60 always;
        root /var/interlegis/sapl/sapl/static/;
        internal;
    }

    error_page 500 502 503 504 /500.html;
    location = /500.html {
        root /var/interlegis/sapl/sapl/static/;
        internal;
    }
}