{ config, pkgs, ... }:

let
  cryptpadConfig = ''
    # CryptPad serves static assets over these two domains.
    # `main_domain` is what users will enter in their address bar.
    # Privileged computation such as key management is handled in this scope
    # UI content is loaded via the `sandbox_domain`.
    # "Content Security Policy" headers prevent content loaded via the sandbox
    # from accessing privileged information.
    # These variables must be different to take advantage of CryptPad's sandboxing techniques.
    # In the event of an XSS vulnerability in CryptPad's front-end code
    # this will limit the amount of information accessible to attackers.
    set $main_domain "cryptpad.codewreck.org";
    set $sandbox_domain "cryptpad-sandbox.codewreck.org";

    # CryptPad's dynamic content (websocket traffic and encrypted blobs)
    # can be served over separate domains. Using dedicated domains (or subdomains)
    # for these purposes allows you to move them to a separate machine at a later date
    # if you find that a single machine cannot handle all of your users.
    # If you don't use dedicated domains, this can be the same as $main_domain
    # If you do, they'll be added as exceptions to any rules which block connections to remote domains.
    set $api_domain "cryptpad.codewreck.org";
    set $files_domain "cryptpad.codewreck.org";

    add_header X-XSS-Protection "1; mode=block";
    add_header X-Content-Type-Options nosniff;
    add_header Access-Control-Allow-Origin "*";
    # add_header X-Frame-Options "SAMEORIGIN";

    # Insert the path to your CryptPad repository root here
    root ${pkgs.cryptpad}/lib/node_modules/cryptpad;
    index index.html;
    error_page 404 /customize.dist/404.html;

    # any static assets loaded with "ver=" in their URL will be cached for a year
    if ($args ~ ver=) {
        set $cacheControl max-age=31536000;
    }
    # Will not set any header if it is emptystring
    add_header Cache-Control $cacheControl;

    # CSS can be dynamically set inline, loaded from the same domain, or from $main_domain
    set $styleSrc   "'unsafe-inline' 'self' ''${main_domain}";

    # connect-src restricts URLs which can be loaded using script interfaces
    set $connectSrc "'self' https://''${main_domain} ''${main_domain} https://''${api_domain} blob: wss://''${api_domain} ''${api_domain} ''${files_domain}";

    # fonts can be loaded from data-URLs or the main domain
    set $fontSrc    "'self' data: ''${main_domain}";

    # images can be loaded from anywhere, though we'd like to deprecate this as it allows the use of images for tracking
    set $imgSrc     "'self' data: * blob: ''${main_domain}";

    # frame-src specifies valid sources for nested browsing contexts.
    # this prevents loading any iframes from anywhere other than the sandbox domain
    set $frameSrc   "'self' ''${sandbox_domain} blob:";

    # specifies valid sources for loading media using video or audio
    set $mediaSrc   "'self' data: * blob: ''${main_domain}";

    # defines valid sources for webworkers and nested browser contexts
    # deprecated in favour of worker-src and frame-src
    set $childSrc   "https://''${main_domain}";

    # specifies valid sources for Worker, SharedWorker, or ServiceWorker scripts.
    # supercedes child-src but is unfortunately not yet universally supported.
    set $workerSrc  "https://''${main_domain}";

    # script-src specifies valid sources for javascript, including inline handlers
    set $scriptSrc  "'self' resource: ''${main_domain}";

    set $unsafe 0;
    # the following assets are loaded via the sandbox domain
    # they unfortunately still require exceptions to the sandboxing to work correctly.
    if ($uri = "/pad/inner.html") { set $unsafe 1; }
    if ($uri = "/sheet/inner.html") { set $unsafe 1; }
    if ($uri ~ ^\/common\/onlyoffice\/.*\/index\.html.*$) { set $unsafe 1; }

    # everything except the sandbox domain is a privileged scope, as they might be used to handle keys
    if ($host != $sandbox_domain) { set $unsafe 0; }

    # privileged contexts allow a few more rights than unprivileged contexts, though limits are still applied
    if ($unsafe) {
        set $scriptSrc "'self' 'unsafe-eval' 'unsafe-inline' resource: ''${main_domain}";
    }

    # Finally, set all the rules you composed above.
    add_header Content-Security-Policy "default-src 'none'; child-src $childSrc; worker-src $workerSrc; media-src $mediaSrc; style-src $styleSrc; script-src $scriptSrc; connect-src $connectSrc; font-src $fontSrc; img-src $imgSrc; frame-src $frameSrc;";

    # The nodejs process can handle all traffic whether accessed over websocket or as static assets
    # We prefer to serve static content from nginx directly and to leave the API server to handle
    # the dynamic content that only it can manage. This is primarily an optimization
    location ^~ /cryptpad_websocket {
        proxy_pass http://[::1]:3000;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

        # WebSocket support (nginx 1.4)
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection upgrade;
    }

    location ^~ /customize.dist/ {
        # This is needed in order to prevent infinite recursion between /customize/ and the root
    }
    # try to load customizeable content via /customize/ and fall back to the default content
    # located at /customize.dist/
    # This is what allows you to override behaviour.
    location ^~ /customize/ {
        rewrite ^/customize/(.*)$ $1 break;
        try_files /customize/$uri /customize.dist/$uri;
    }

    # /api/config is loaded once per page load and is used to retrieve
    # the caching variable which is applied to every other resource
    # which is loaded during that session.
    location = /api/config {
        proxy_pass http://[::1]:3000;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    }

    # encrypted blobs are immutable and are thus cached for a year
    location ^~ /blob/ {
        root /www/cryptpad;
        add_header X-XSS-Protection "1; mode=block";
        add_header X-Content-Type-Options nosniff;
        add_header Content-Security-Policy "default-src 'none'; child-src $childSrc; worker-src $workerSrc; media-src $mediaSrc; style-src $styleSrc; script-src $scriptSrc; connect-src $connectSrc; font-src $fontSrc; img-src $imgSrc; frame-src $frameSrc;";
        if ($request_method = 'OPTIONS') {
            add_header Cache-Control $cacheControl;
            add_header X-XSS-Protection "1; mode=block";
            add_header X-Content-Type-Options nosniff;
            add_header Content-Security-Policy "default-src 'none'; child-src $childSrc; worker-src $workerSrc; media-src $mediaSrc; style-src $styleSrc; script-src $scriptSrc; connect-src $connectSrc; font-src $fontSrc; img-src $imgSrc; frame-src $frameSrc;";
            add_header 'Access-Control-Allow-Origin' '*';
            add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
            add_header 'Access-Control-Allow-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range';
            add_header 'Access-Control-Max-Age' 1728000;
            add_header 'Content-Type' 'application/octet-stream; charset=utf-8';
            add_header 'Content-Length' 0;
            return 204;
        }
        add_header Cache-Control max-age=31536000;
        add_header 'Access-Control-Allow-Origin' '*';
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
        add_header 'Access-Control-Allow-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range';
        add_header 'Access-Control-Expose-Headers' 'DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range';
        try_files $uri =404;
    }

    # the "block-store" serves encrypted payloads containing users' drive keys
    # these payloads are unlocked via login credentials. They are mutable
    # and are thus never cached. They're small enough that it doesn't matter, in any case.
    location ^~ /block/ {
        root /www/cryptpad;
        add_header X-XSS-Protection "1; mode=block";
        add_header X-Content-Type-Options nosniff;
        add_header Access-Control-Allow-Origin "*";
        add_header Content-Security-Policy "default-src 'none'; child-src $childSrc; worker-src $workerSrc; media-src $mediaSrc; style-src $styleSrc; script-src $scriptSrc; connect-src $connectSrc; font-src $fontSrc; img-src $imgSrc; frame-src $frameSrc;";
        add_header Cache-Control max-age=0;
        try_files $uri =404;
    }

    # This block provides an alternative means of loading content
    # otherwise only served via websocket. This is solely for debugging purposes,
    # and is thus not allowed by default.
    #location ^~ /datastore/ { # nixos: possibly also blobstage, data, pins, tasks
        #root /www/cryptpad;
        #add_header Cache-Control max-age=0;
        #try_files $uri =404;
    #}

    # ugly hack: disable registration
    location /register {
        deny all;
    }


    # The nodejs server has some built-in forwarding rules to prevent
    # URLs like /pad from resulting in a 404. This simply adds a trailing slash
    # to a variety of applications.
    location ~ ^/(register|login|settings|user|pad|drive|poll|slide|code|whiteboard|file|media|profile|contacts|todo|filepicker|debug|kanban|sheet|support|admin|notifications|teams)$ {
        rewrite ^(.*)$ $1/ redirect;
    }

    # Finally, serve anything the above exceptions don't govern.
    try_files /www/$uri /www/$uri/index.html /customize/$uri;
  '';
in {

  imports = [ ../../profiles/nginx.nix ];

  systemd.services.nginx = {
    serviceConfig.BindReadOnlyPaths = [
      "/home/asmadeus/www:/www/local"
      "/var/lib/private/cryptpad:/www/cryptpad"
    ];
  };

  services.nginx.virtualHosts =  {
    "jormungand.codewreck.org" = {
      forceSSL = true;
      enableACME = true;
      locations."/mpd/" = {
        proxyPass = "http://127.0.0.1:8080/";
        # /var/spool/nginx/mpd.htpasswd has been populated manually
        # until proper secrets get managed...
        extraConfig = ''
          auth_basic "mpd";
          auth_basic_user_file /var/spool/nginx/mpd.htpasswd;
        '';
      };
      locations."/local/" = {
        root = "/www";
      };
      locations."/" = {
        extraConfig = ''
          rewrite ^ https://codewreck.org$request_uri? redirect;
        '';
      };
    };

    "miniflux.codewreck.org" = {
      forceSSL = true;
      enableACME = true;
      locations."/" = {
        proxyPass = "http://[::1]:8081/";
      };
    };

    "matrix.codewreck.org" = {
      forceSSL = true;
      enableACME = true;
      locations."/".extraConfig = ''
        return 404;
      '';
      locations."/_matrix" = {
        proxyPass = "http://[::1]:8008";
      };
    };

    "riot.codewreck.org" = {
      forceSSL = true;
      enableACME = true;
      root = pkgs.element-web.override {
        conf = {
          default_server_config."m.homeserver" = {
            "base_url" = "https://matrix.codewreck.org";
            "server_name" = "codewreck.org";
          };
        };
      };
    };

    "cryptpad.codewreck.org" = {
      forceSSL = true;
      enableACME = true;
      extraConfig = cryptpadConfig;
    };
    "cryptpad-sandbox.codewreck.org" = {
      forceSSL = true;
      enableACME = true;
      extraConfig = cryptpadConfig;
    };
  };
}