dotfiles/modules/nixos/services/gitea.nix

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

let giteaPath = "/var/lib/gitea"; # Default service directory

in {

  config = lib.mkIf config.services.gitea.enable {
    services.gitea = {
      database.type = "sqlite3";
      settings = {
        actions.ENABLED = true;
        metrics.ENABLED = true;
        repository = {
          # Pushing to a repo that doesn't exist automatically creates one as
          # private.
          DEFAULT_PUSH_CREATE_PRIVATE = true;

          # Allow git over HTTP.
          DISABLE_HTTP_GIT = false;

          # Allow requests hitting the specified hostname.
          ACCESS_CONTROL_ALLOW_ORIGIN = config.hostnames.git;

          # Automatically create viable users/orgs on push.
          ENABLE_PUSH_CREATE_USER = true;
          ENABLE_PUSH_CREATE_ORG = true;

          # Default when creating new repos.
          DEFAULT_BRANCH = "main";
        };
        server = {
          HTTP_PORT = 3001;
          HTTP_ADDRESS = "127.0.0.1";
          ROOT_URL = "https://${config.hostnames.git}/";
          SSH_PORT = 22;
          START_SSH_SERVER = false; # Use sshd instead
          DISABLE_SSH = false;
        };

        # Don't allow public users to register accounts.
        service.DISABLE_REGISTRATION = true;

        # Force using HTTPS for all session access.
        session.COOKIE_SECURE = true;

        # Hide users' emails.
        ui.SHOW_USER_EMAIL = false;
      };
      extraConfig = null;
    };

    networking.firewall.allowedTCPPorts = [ 122 ];
    users.users.${config.user}.extraGroups = [ "gitea" ];

    caddy.routes = [
      # Prevent public access to Prometheus metrics.
      {
        match = [{
          host = [ config.hostnames.git ];
          path = [ "/metrics*" ];
        }];
        handle = [{
          handler = "static_response";
          status_code = "403";
        }];
      }
      # Allow access to primary server.
      {
        match = [{ host = [ config.hostnames.git ]; }];
        handle = [{
          handler = "reverse_proxy";
          upstreams = [{
            dial = "localhost:${
                builtins.toString
                config.services.gitea.settings.server.HTTP_PORT
              }";
          }];
        }];
      }
    ];

    # Configure Cloudflare DNS to point to this machine
    services.cloudflare-dyndns.domains = [ config.hostnames.git ];

    # Scrape the metrics endpoint for Prometheus.
    prometheus.scrapeTargets = [
      "127.0.0.1:${
        builtins.toString config.services.gitea.settings.server.HTTP_PORT
      }"
    ];

    ## Backup config

    # Open to groups, allowing for backups
    systemd.services.gitea.serviceConfig.StateDirectoryMode =
      lib.mkForce "0770";
    systemd.tmpfiles.rules =
      [ "f ${giteaPath}/data/gitea.db 0660 gitea gitea" ];

    # Allow litestream and gitea to share a sqlite database
    users.users.litestream.extraGroups = [ "gitea" ];
    users.users.gitea.extraGroups = [ "litestream" ];

    # Backup sqlite database with litestream
    services.litestream = {
      settings = {
        dbs = [{
          path = "${giteaPath}/data/gitea.db";
          replicas = [{
            url =
              "s3://${config.backup.s3.bucket}.${config.backup.s3.endpoint}/gitea";
          }];
        }];
      };
    };

    # Don't start litestream unless gitea is up
    systemd.services.litestream = {
      after = [ "gitea.service" ];
      requires = [ "gitea.service" ];
    };

    # Run a repository file backup on a schedule
    systemd.timers.gitea-backup = lib.mkIf (config.backup.s3.endpoint != null) {
      timerConfig = {
        OnCalendar = "*-*-* 00:00:00"; # Once per day
        Unit = "gitea-backup.service";
      };
      wantedBy = [ "timers.target" ];
    };

    # Backup Gitea repos to object storage
    systemd.services.gitea-backup =
      lib.mkIf (config.backup.s3.endpoint != null) {
        description = "Backup Gitea data";
        environment.AWS_ACCESS_KEY_ID = config.backup.s3.accessKeyId;
        serviceConfig = {
          Type = "oneshot";
          User = "gitea";
          Group = "backup";
          EnvironmentFile = config.secrets.backup.dest;
        };
        script = ''
          ${pkgs.awscli2}/bin/aws s3 sync --exclude */gitea.db* \
              ${giteaPath}/ \
              s3://${config.backup.s3.bucket}/gitea-data/ \
              --endpoint-url=https://${config.backup.s3.endpoint}
        '';
      };

  };

}