# Work Package Suite — NGINX site config
# This container sits behind an external reverse proxy that handles SSL.
# It listens on port 80 (plain HTTP on the internal Docker network).

# Cache-Control per file type, computed here rather than in a nested location.
# WHY A MAP: nginx's add_header is not inherited into a block that declares its own
# add_header — a `location ~* \.(html|css|js)$` that set only Cache-Control would have
# silently dropped the CSP / HSTS / X-Frame-Options / nosniff headers below for exactly
# those files. Computing the value here keeps every header in ONE scope. An empty value
# means nginx omits the header entirely, so images and fonts stay freely cacheable.
#
# Code assets must revalidate on every load: with no Cache-Control at all the browser
# applies HEURISTIC freshness (~10% of the file's age), so the least recently changed
# file gets the LONGEST lifetime — which is how a page ends up running against a
# stylesheet or script from a previous deploy. ETag/Last-Modified keep it a cheap 304.
map $uri $wp_cache_control {
    default                             "";
    ~*\.(?:html|css|js|webmanifest)$    "no-cache";
    ~*/$                                "no-cache";   # directory index → index.html
}

server {
    listen 80;
    server_name wp.controls.dev;

    root /usr/share/nginx/html;
    index index.html;

    # ── Security response headers (defense-in-depth) ─────────────────────────
    # CSP keeps 'unsafe-inline' for now because the app uses inline handlers/styles
    # heavily; even so, connect-src/img-src/object-src/base-uri/frame-ancestors
    # sharply limit what injected script could load or exfiltrate. Tighten toward
    # nonce-based scripts once inline handlers are refactored.
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-Frame-Options "SAMEORIGIN" always;
    add_header Referrer-Policy "no-referrer" always;
    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
    add_header Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline'; style-src 'self' 'unsafe-inline'; img-src 'self' data: blob:; font-src 'self'; connect-src 'self'; object-src 'none'; base-uri 'none'; frame-ancestors 'self'; form-action 'self'" always;
    # Empty for anything that isn't code, in which case nginx omits the header.
    add_header Cache-Control $wp_cache_control always;

    location / {
        try_files $uri $uri/ =404;
    }

    # Proxy /api/ to the FastAPI container (service name "api" on the internal network)
    location /api/ {
        proxy_pass http://api:8000;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $remote_addr;
        # This container is only ever reached via the TLS-terminating external
        # proxy, so the real client scheme is HTTPS. Hard-set it (a local $scheme
        # here is always "http") so the API marks the session cookie Secure.
        proxy_set_header X-Forwarded-Proto https;
        client_max_body_size 5m;
    }
}