# HTTP-only edge for «Контракт-чек» behind a front proxy (VPS layout).
# TLS is terminated by the host nginx (deploy/vps/front.conf); this edge only
# forwards to the api service. Same envsubst vars as the TLS template:
# NGINX_SERVER_NAME (expanded by the nginx Docker entrypoint).

# Dynamic DNS resolution: when the API container is recreated it gets a new
# IP. Using a variable with proxy_pass forces nginx to re-resolve `api`
# against Docker's embedded DNS every `valid=` interval instead of caching the
# address at startup.
resolver 127.0.0.11 valid=10s;

log_format contract_check '$remote_addr - $remote_user [$time_local] "$request" '
                            '$status $body_bytes_sent "$http_referer" '
                            '"$http_user_agent" "$http_x_forwarded_for" '
                            'rt=$request_time cid=$http_x_correlation_id';

access_log  /var/log/nginx/access.log  contract_check;

client_max_body_size 50M;

server {
    listen 80;
    # IPv6 too — otherwise IPv6 clients fall through to nginx's stock
    # default.conf server (static /usr/share/nginx/html → 404s).
    listen [::]:80;
    # `localhost` keeps the container healthcheck (Host: localhost) on this
    # server instead of falling through to nginx's stock default.conf (404).
    # conf.d loads contract-check.conf first, so this name wins the conflict.
    server_name ${NGINX_SERVER_NAME} localhost;

    location ~ ^/(healthz|readyz|metrics|api/|admin/|docs|openapi.json) {
        # Variable forces dynamic DNS resolution for `api`.
        set $api http://api:8000;
        proxy_pass $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 $http_x_forwarded_proto;
        proxy_set_header X-Forwarded-Host  $host;
        proxy_set_header X-Correlation-Id  $http_x_correlation_id;

        proxy_connect_timeout 10s;
        proxy_send_timeout    30s;
        proxy_read_timeout    120s;
        proxy_buffering       off;
    }

    location /webhook/ {
        # Variable forces dynamic DNS resolution for `api`.
        set $api http://api:8000;
        proxy_pass $api/api/v1/webhooks/;
        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 $http_x_forwarded_proto;

        proxy_connect_timeout 10s;
        proxy_send_timeout    30s;
        proxy_read_timeout    60s;
    }

    # Grafana / Loki: exposed under /grafana so everything lives on one domain.
    # In production restrict access here or via firewall (basic auth / VPN / SSO).
    location /grafana/ {
        # Variable forces dynamic DNS resolution for `grafana`.
        set $grafana http://grafana:3000;
        proxy_pass $grafana;
        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 $http_x_forwarded_proto;
        proxy_set_header X-Forwarded-Host  $host;
        proxy_set_header X-Correlation-Id  $http_x_correlation_id;

        # Grafana needs the subpath so it can build correct links/redirects.
        proxy_set_header X-Forwarded-Prefix /grafana;

        proxy_connect_timeout 10s;
        proxy_send_timeout    30s;
        proxy_read_timeout    60s;
        proxy_buffering       off;
    }

    location /stub_status {
        stub_status on;
        allow 10.0.0.0/8;
        allow 172.16.0.0/12;
        allow 192.168.0.0/16;
        allow 127.0.0.1;
        deny all;
    }

    location / {
        return 404;
    }
}