{ lib, pkgs, ... }:
let
  inherit (builtins) readFile;
  inherit (lib) mkOption types;
in
{
  _class = "clan.service";

  manifest = {
    name = "amarth-services/zitadel";
    description = "Zitadel service module";
    categories = [ "System" "Identity" "IAM" ];
    readme = readFile ./README.md;
  };

  #==============================================================================================================
  # Controller configuration
  #==============================================================================================================
  roles.controller = {
    interface = {
      options = {
        hostName = mkOption {
          type = types.str;
          example = "auth.example.com";
          description = ''
            The domain at which zitadel will be hosted
          '';
        };

        displayName = mkOption {
          type = types.str;
          example = "My awesome org";
          description = ''
            The Name of the zitadel organisation
          '';
        };

        emergencyAccessPublicKey = mkOption {
          type = types.str;
          example = "ssh-ed25519 ...";
          description = ''
            The public key with which you want access to
          '';
        };
      };
    };

    perInstance = { instanceName, settings, machine, roles, ... }: {
      nixosModule = { config, pkgs, inputs, system, ... }: 
      let
        terraform = inputs.terranix.lib.terranixConfiguration {
          inherit pkgs system;

          modules = [
            ({ config, ... }: {
              config = {
                terraform.required_providers.zitadel = {
                  source = "zitadel/zitadel";
                  version = "2.2.0";
                };

                provider.zitadel = {
                  domain = "localhost";
                  insecure = "true";
                  port = "8080";
                  jwt_profile_file = "local-token";
                };

                resource.zitadel_human_user.default = {
                  org_id = "";
                };
              };
            })
          ];
        };
      in
      {
        clan.core.vars.generators.zitadel = {
          share = false;

          files.masterKey = { deploy = true; secret = true; owner = "zitadel"; group = "zitadel"; mode = "0400"; };
          files.initialAdminPassword = { deploy = false; secret = false; };
          files.emailPassword = { deploy = false; secret = true; };

          runtimeInputs = with pkgs; [ pwgen ];

          script = ''
            pwgen 50 1 > "$out/initialAdminPassword"

            # https://zitadel.com/docs/self-hosting/manage/configure#masterkey
            # The master key has to be 32 bytes
            head -c 32 /dev/urandom > "$out/masterKey"

            touch $out/emailPassword
          '';
        };

        services.zitadel = {
          enable = true;

          openFirewall = true;

          masterKeyFile = config.clan.core.vars.generators.zitadel.files.masterKey.path;
          tlsMode = "external";

          settings = {
            Port = 9092;

            ExternalDomain = settings.hostName;
            ExternalPort = 443;
            ExternalSecure = true;

            Metrics.Type = "otel";
            Tracing.Type = "otel";
            Telemetry.Enabled = true;

            SystemDefaults = {
              PasswordHasher.Hasher.Algorithm = "argon2id";
              SecretHasher.Hasher.Algorithm = "argon2id";
            };

            DefaultInstance = {
              PasswordComplexityPolicy = {
                MinLength = 20;
                HasLowercase = false;
                HasUppercase = false;
                HasNumber = false;
                HasSymbol = false;
              };
              LoginPolicy = {
                AllowRegister = false;
                ForceMFA = true;
              };
              LockoutPolicy = {
                MaxPasswordAttempts = 5;
                MaxOTPAttempts = 10;
              };
              SMTPConfiguration = {
                SMTP = {
                  Host = "black-mail.nl:587";
                  User = "info@amarth.cloud";
                  Password = ""; #config.clan.core.vars.generators.zitadel.files.emailPassword.value;
                };
                FromName = "Amarth Zitadel";
              };
            };

            Database.postgres = {
              Host = "localhost";
              # Zitadel will report error if port is not set
              Port = 5432;
              Database = "zitadel";
              User = {
                Username = "zitadel";
                SSL.Mode = "disable";
              };
              Admin = {
                Username = "postgres";
                SSL.Mode = "disable";
              };
            };

            Machine.Identification = {
              PrivateIp.Enabled = true;

              # In the docs this uses a google service. I want a self hosted one
              # TODO :: Figure out how to self-host webhooks, if I want them at all
              Webhook.Enabled = false;
            };

            SystemAPIUsers = {
              emergencyAccess = {
                # Path = settings.emergencyAccessPublicKey;
                KeyData = settings.emergencyAccessPublicKey;

                # This is the default value
                # Memberships = [
                #   { MemberType = "System"; Roles = [ "SYSTEM_OWNER" ]; }
                # ];
              };
            };
          };

          steps.FirstInstance = {
            InstanceName = settings.hostName;

            Org = {
              Name = settings.displayName;
              Human = {
                UserName = "chris";
                FirstName = "Chris";
                LastName = "Kruining";
                Email = {
                  Address = "chris@kruining.eu";
                  Verified = true;
                };
                Password = config.clan.core.vars.generators.zitadel.files.initialAdminPassword.value;
              };
            };
          };
        };

        services.postgresql = {
          enable = true;
          authentication = ''
            # Generated file, do not edit!
            # TYPE  DATABASE  USER  ADDRESS       METHOD
            local   all       all                 trust
            host    all       all   127.0.0.1/32  trust
            host    all       all   ::1/128       trust
          '';
          ensureDatabases = [ "zitadel" ];
          ensureUsers = [
            {
              name = "zitadel";
              ensureDBOwnership = true;
            }
          ];
        };
      };
    };
  };

  #==============================================================================================================
  # Peer configuration
  #==============================================================================================================
  roles.peer = {
    interface = {
      options = {};
    };

    perInstance = { instanceName, settings, machine, roles, ... }: {
      nixosModule = {};
    };
  };
}