# Helper to get scheme regardless if we are behind a proxy or not
map $http_x_forwarded_proto $forwardscheme {
    default $scheme;
    https https;
}

# COEP and COOP headers for cross-origin isolation, which are set only for the
# EmulatorJS player path, to enable SharedArrayBuffer support, which is needed
# for multi-threaded cores.
map $request_uri $coep_header {
    default        "";
    ~^/rom/.*/ejs$ "require-corp";
}
map $request_uri $coop_header {
    default        "";
    ~^/rom/.*/ejs$ "same-origin";
}

server {
    root /app/code/frontend;
    listen 3000;
    listen [::]:3000;

    proxy_set_header Host $http_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 $forwardscheme;

    location / {
        try_files $uri $uri/ /index.html;
        proxy_redirect off;
        add_header Access-Control-Allow-Origin *;
        add_header Access-Control-Allow-Methods *;
        add_header Access-Control-Allow-Headers *;
        add_header Cross-Origin-Embedder-Policy $coep_header;
        add_header Cross-Origin-Opener-Policy $coop_header;
    }

    # Static files
    location /assets {
        try_files $uri $uri/ =404;
    }

    # OpenAPI for swagger and redoc
    location /openapi.json {
        proxy_pass http://backend_server;
    }

    # Backend api calls
    location /api {
        proxy_pass http://backend_server;
        proxy_request_buffering off;
        proxy_buffering off;
    }
    location ~ ^/(ws|netplay) {
        proxy_pass http://backend_server;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
    }

    # Internally redirect download requests
    location /library/ {
        internal;
        alias "/app/data/library/";
    }

    # Internal decoding endpoint, used to decode base64 encoded data
    location /decode {
        internal;
        js_content decode.decodeBase64;
    }
}
