map $http_upgrade $connection_upgrade {
    default upgrade;
    '' close;
}

upstream backend_upstream {
    server backend:8000;
}

upstream runtime_upstream {
    server runtime:8000;
}

upstream jupyter_upstream {
    server jupyter:8888;
}

server {
    listen 80;
    server_name _;
    client_max_body_size 100m;

    location = /health {
        default_type application/json;
        return 200 '{"status":"ok","service":"gateway"}';
    }

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

    location / {
        try_files $uri $uri/ /index.html;
    }

    location /api/ {
        proxy_pass http://backend_upstream;
        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 X-Request-ID $request_id;
    }

    location = /_jupyter_auth {
        internal;
        proxy_pass http://runtime_upstream/internal/v1/jupyter/authorize;
        proxy_pass_request_body off;
        proxy_set_header Content-Length "";
        proxy_set_header Cookie $http_cookie;
        proxy_set_header X-Original-URI $request_uri;
        proxy_set_header X-Request-ID $request_id;
        proxy_set_header X-Service-Token "${INTERNAL_SERVICE_TOKEN}";
    }

    location = /jupyter {
        return 308 /jupyter/;
    }

    location ^~ /jupyter/ {
        auth_request /_jupyter_auth;
        auth_request_set $jupyter_authorization
            $upstream_http_x_jupyter_authorization;

        proxy_pass http://jupyter_upstream;
        proxy_http_version 1.1;
        proxy_set_header Authorization $jupyter_authorization;
        proxy_set_header Host $http_host;
        proxy_set_header Origin $http_origin;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection $connection_upgrade;
        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 X-Forwarded-Prefix /jupyter;
        proxy_set_header X-Request-ID $request_id;
        proxy_buffering off;
        proxy_request_buffering off;
        proxy_read_timeout 3600s;
        proxy_send_timeout 3600s;
        proxy_redirect off;
    }
}