# NixOps configuration for the hosts running a Matrix server (synapse)

{ config, pkgs, lib, ... }:

{

  imports = [
    ../secrets/matrix.nix
  ];

  i18n = {
    extraLocaleSettings = {
      LC_COLLATE = "C";   # Ensure correct locale for postgres
      LC_CTYPE = "C";     # Ensure correct locale for postgres
    };
  };

  services = {

    matrix-synapse = {
      enable = true;                                          # Enable the synapse server
      server_name = "mcwhirter.io";                           # Server's public domain name
      public_baseurl = "https://synapse.mcwhirter.io:443/";   # Matrix target URL
      enable_registration = true;                             # Toggle user registration
      listeners = [
        { # federation
          bind_address = "";
          port = 8448;
          resources = [
            { compress = true; names = [ "client" ]; }
            { compress = false; names = [ "federation" ]; }
          ];
          tls = true;
          type = "http";
          x_forwarded = false;
        }
        { # client
          bind_address = "::1";                                 # Listen on localhost only
          port = 8008;                                          # Port to listen on
          resources = [
            {
              compress = true;
              names = [ "client" ];
            } {
              compress = false;
              names = [ "federation" ];
          } ];
          tls = true;
          type = "http";
          x_forwarded = true;
        }
      ];
      max_upload_size = "200M";                               # Also set client_max_body_size to at least this
      tls_certificate_path = "/var/lib/acme/mcwhirter.io/fullchain.pem";
      tls_private_key_path = "/var/lib/acme/mcwhirter.io/key.pem";
      turn_shared_secret = "IZI43ylg6aJdMwy5MyhUPqT8SJD4C3P1vDcIFMzqGvTXJiCjAEvnPcDCBZfig5Q6";
      turn_uris = [
        "turn:turn.mcwhirter.io:5349?transport=udp"
        "turn:turn.mcwhirter.io:5350?transport=udp"
        "turn:turn.mcwhirter.io:5349?transport=tcp"
        "turn:turn.mcwhirter.io:5350?transport=tcp"
      ];
      url_preview_enabled = true;
      extraConfig = ''
        enable_group_creation: true   # Allow users to create communities
      '';
    };

    nginx = {
      enable = true;
      recommendedTlsSettings = true;
      recommendedOptimisation = true;
      recommendedGzipSettings = true;
      recommendedProxySettings = true;
      virtualHosts = {
        "synapse.mcwhirter.io" = {
          forceSSL = true;
          enableACME = true;
          locations = {
            "/_matrix" = {
              proxyPass = "https://[::1]:8008";
            };
            "/.well-known/matrix/server".extraConfig =
              let
                # use 443 instead of the default 8448 port to unite
                # the client-server and server-server port for simplicity
                server = { "m.server" = "synapse.mcwhirter.io:443"; };
              in ''
                add_header Content-Type application/json;
                return 200 '${builtins.toJSON server}';
              '';
            "= /.well-known/matrix/client".extraConfig =
              let
                client = {
                  "m.homeserver" =  { "base_url" = "https://synapse.mcwhirter.io"; };
                  "m.identity_server" =  { "base_url" = "https://vector.im"; };
                };
              # ACAO required to allow element-web on any URL to request this json file
              in ''
                add_header Content-Type application/json;
                add_header Access-Control-Allow-Origin *;
                return 200 '${builtins.toJSON client}';
              '';
          };
          extraConfig = ''
            client_max_body_size 200M;   # Needs to be no less than max_upload_size
          '';
        };
        "chat.mcwhirter.io" = {
          forceSSL = true;
          enableACME = true;
          root = pkgs.element-web;   # Install RIOT web in the nginx root
        };
      };
    };

    postgresql = {
      enable = true;
      ensureDatabases = [ "matrix-synapse" ];    # Ensure the database persists
      ensureUsers = [
        {
          name = "matrix-synapse";               # Ensure the database user persists
          ensurePermissions = {                  # Ensure the database permissions persist
            "DATABASE \"matrix-synapse\"" = "ALL PRIVILEGES";
            "ALL TABLES IN SCHEMA public" = "ALL PRIVILEGES";
          };
        }
      ];
      # Initial database creation
      initialScript = pkgs.writeText "synapse-init.sql" ''
        CREATE ROLE "matrix-synapse" WITH LOGIN PASSWORD 'synapse';
        CREATE DATABASE "matrix-synapse" WITH OWNER "matrix-synapse"
          TEMPLATE template0
          LC_COLLATE = "C"
          LC_CTYPE = "C";
      '';
    };
  };

  security.acme = {
    acceptTerms = true;
    certs = {
      "chat.mcwhirter.io" = {
        postRun = "systemctl reload nginx.service";
        email = "acme@mcwhirter.io";
      };
      "synapse.mcwhirter.io" = {
        group = "matrix-synapse";
        postRun = "systemctl reload nginx.service; systemctl restart matrix-synapse.service";
        email = "acme@mcwhirter.io";
      };
    };
  };

  networking.firewall = {
    enable = true;
    allowedTCPPorts = [
      443    # HTTPS
      8448   # Matrix federation
    ];
  };

  users.groups.matrix-synapse.members = [ "nginx" ];   # Added for keys permissions

}