server {
    listen 80;
    server_name _;

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

    # CV / multipart uploads (MAX_PDF_SIZE_MB is 10; leave headroom for form fields).
    client_max_body_size 25m;

    # Resolve backend-api through Docker's embedded DNS on each request instead of
    # once at startup. `docker compose up` recreates backend-api with a new IP;
    # a static upstream keeps the old one and every API call 502s until nginx restarts.
    # proxy_pass with a variable and no URI forwards the original request URI unchanged.
    resolver 127.0.0.11 valid=10s ipv6=off;
    set $backend_api http://backend-api:8000;

    # Security headers on every response.
    add_header X-Content-Type-Options nosniff always;
    add_header X-Frame-Options DENY always;
    add_header Referrer-Policy strict-origin-when-cross-origin always;

    # Same-origin API proxy. The SPA is built with an empty VITE_API_BASE so
    # fetch('/jobs/fetch') stays on this host. OpenAPI (/docs, /redoc,
    # /openapi.json) is intentionally NOT proxied.
    #
    # Paths that are BOTH React routes (/jobs, /inbox, …) and API prefixes must
    # require a sub-path: otherwise a cold open / refresh of /jobs is stolen by
    # the proxy and returns a FastAPI 404 instead of index.html.

    # SPA page roots that also prefix API calls — sub-path required.
    location ~ ^/(jobs|inbox|pipeline|tasks|assessments|offers|managers|analytics|notifications)/ {
        proxy_pass $backend_api;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Authorization $http_authorization;
        proxy_connect_timeout 10s;
        proxy_send_timeout 120s;
        proxy_read_timeout 120s;
        proxy_request_buffering off;
    }

    # API-only prefixes (no SPA page at the bare path).
    location ~ ^/(health|users|roles|permissions|permission-tags|email|job|candidate|notes|interview|feedback|activity|org-settings|saved-searches|search|documents|sheet|s3|forms|department)(/|$) {
        proxy_pass $backend_api;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Authorization $http_authorization;
        proxy_connect_timeout 10s;
        proxy_send_timeout 120s;
        proxy_read_timeout 120s;
        proxy_request_buffering off;
    }

    # One SPA at `/`. Without this, /auth/confirm-email (a router path, not a
    # file) 404s when a confirmation email link is opened cold.
    location / {
        try_files $uri $uri/ /index.html;
    }

    # Hashed filenames, so they can be cached hard. A miss after a rebuild is a
    # stale tab (old import() hash) — 404 + immutable would pin that miss for a
    # year, so JS falls through to a one-shot reload of index.html.
    location /assets/ {
        expires 1y;
        add_header Cache-Control "public, immutable";
        add_header X-Content-Type-Options nosniff always;
        add_header X-Frame-Options DENY always;
        add_header Referrer-Policy strict-origin-when-cross-origin always;

        location ~ \.js$ {
            expires 1y;
            add_header Cache-Control "public, immutable";
            add_header X-Content-Type-Options nosniff always;
            add_header X-Frame-Options DENY always;
            add_header Referrer-Policy strict-origin-when-cross-origin always;
            try_files $uri @stale_js;
        }
    }

    location @stale_js {
        default_type application/javascript;
        add_header Cache-Control "no-store" always;
        add_header X-Content-Type-Options nosniff always;
        return 200 "try{if(!sessionStorage.getItem('tf-chunk-reload')){sessionStorage.setItem('tf-chunk-reload','1');location.reload();}else{sessionStorage.removeItem('tf-chunk-reload');}}catch(e){location.reload();}";
    }

    # index.html must never be cached, or a redeploy keeps serving the old asset hashes.
    location = /index.html {
        etag off;
        if_modified_since off;
        add_header Cache-Control "no-store, no-cache, must-revalidate, max-age=0" always;
        add_header Pragma "no-cache" always;
        add_header X-Content-Type-Options nosniff always;
        add_header X-Frame-Options DENY always;
        add_header Referrer-Policy strict-origin-when-cross-origin always;
    }

    gzip on;
    gzip_min_length 1024;
    gzip_types text/css text/javascript application/javascript application/json image/svg+xml;
}