{ config, lib, pkgs, ... }:
let
  cfg = config.shb.karakeep;

  contracts = pkgs.callPackage ../contracts {};
in
{
  imports = [
    ../blocks/nginx.nix
  ];

  options.shb.karakeep = {
    enable = lib.mkEnableOption "the Karakeep service";

    subdomain = lib.mkOption {
      type = lib.types.str;
      description = "Subdomain under which Karakeep will be served.";
      default = "karakeep";
    };

    domain = lib.mkOption {
      type = lib.types.str;
      description = "domain under which Karakeep will be served.";
      example = "mydomain.com";
    };

    ssl = lib.mkOption {
      description = "Path to SSL files";
      type = lib.types.nullOr contracts.ssl.certs;
      default = null;
    };

    port = lib.mkOption {
      type = lib.types.port;
      description = "Port Karakeep listens to incoming requests.";
      default = 3000;
    };

    environment = lib.mkOption {
      default = {};
      type = lib.types.attrsOf lib.types.str;
      description = "Extra environment variables. See https://docs.karakeep.app/configuration/";
      example = ''
      {
        OLLAMA_BASE_URL = "http://127.0.0.1:''${toString config.services.ollama.port}";
        INFERENCE_TEXT_MODEL = "deepseek-r1:1.5b";
        INFERENCE_IMAGE_MODEL = "llava";
        EMBEDDING_TEXT_MODEL = "nomic-embed-text:v1.5";
        INFERENCE_ENABLE_AUTO_SUMMARIZATION = "true";
        INFERENCE_JOB_TIMEOUT_SEC = "200";
      }
      '';
    };

    ldap = lib.mkOption {
      description = ''
        Setup LDAP integration.
      '';
      default = {};
      type = lib.types.submodule {
        options = {
          userGroup = lib.mkOption {
            type = lib.types.str;
            description = "Group users must belong to to be able to login.";
            default = "karakeep_user";
          };
        };
      };
    };

    sso = lib.mkOption {
      description = ''
        Setup SSO integration.
      '';
      default = {};
      type = lib.types.submodule {
        options = {
          enable = lib.mkEnableOption "SSO integration.";

          authEndpoint = lib.mkOption {
            type = lib.types.nullOr lib.types.str;
            default = null;
            description = "Endpoint to the SSO provider. Leave null to not have SSO configured.";
            example = "https://authelia.example.com";
          };

          clientID = lib.mkOption {
            type = lib.types.str;
            description = "Client ID for the OIDC endpoint.";
            default = "karakeep";
          };

          authorization_policy = lib.mkOption {
            type = lib.types.enum [ "one_factor" "two_factor" ];
            description = "Require one factor (password) or two factor (device) authentication.";
            default = "one_factor";
          };

          nextauthSecret = lib.mkOption {
            description = "NextAuth secret.";
            type = lib.types.submodule {
              options = contracts.secret.mkRequester {
                owner = "karakeep";
                restartUnits = [ "karakeep.service" ];
              };
            };
          };

          sharedSecret = lib.mkOption {
            description = "OIDC shared secret for Karakeep.";
            type = lib.types.submodule {
              options = contracts.secret.mkRequester {
                owner = "karakeep";
                restartUnits = [ "karakeep.service" ];
              };
            };
          };

          sharedSecretForAuthelia = lib.mkOption {
            description = "OIDC shared secret for Authelia. Must be the same as `sharedSecret`";
            type = lib.types.submodule {
              options = contracts.secret.mkRequester {
                mode = "0400";
                ownerText = "config.shb.authelia.autheliaUser";
                owner = config.shb.authelia.autheliaUser;
              };
            };
          };
        };
      };
    };

    backup = lib.mkOption {
      description = ''
        Backup state directory.
      '';
      default = {};
      type = lib.types.submodule {
        options = contracts.backup.mkRequester {
          user = "karakeep";
          sourceDirectories = [
            "/var/lib/karakeep"
          ];
        };
      };
    };
  };

  config = (lib.mkMerge [
    (lib.mkIf cfg.enable {
      services.karakeep = {
        enable = true;

        extraEnvironment = {
          PORT = toString cfg.port;
          DISABLE_NEW_RELEASE_CHECK = "true"; # These are handled by NixOS
        } // cfg.environment;
      };

      shb.nginx.vhosts = [
        {
          inherit (cfg) subdomain domain ssl;
          upstream = "http://127.0.0.1:${toString cfg.port}/";
        }
      ];
    })
    (lib.mkIf (cfg.enable && cfg.sso.enable) {
      shb.lldap.ensureGroups = {
        ${cfg.ldap.userGroup} = {};
      };

      shb.authelia.extraOidcAuthorizationPolicies.karakeep = {
        default_policy = "deny";
        rules = [
          {
            subject = [ "group:${cfg.ldap.userGroup}" ];
            policy = cfg.sso.authorization_policy;
          }
        ];
      };
      shb.authelia.oidcClients = [
        {
          client_id = cfg.sso.clientID;
          client_secret.source = cfg.sso.sharedSecretForAuthelia.result.path;
          scopes = [ "openid" "email" "profile" ];
          authorization_policy = "karakeep";
          redirect_uris = [
            "https://${cfg.subdomain}.${cfg.domain}/api/auth/callback/custom"
          ];
        }
      ];
      services.karakeep = {
        extraEnvironment = {
          DISABLE_SIGNUPS = "false";
          DISABLE_PASSWORD_AUTH = "true";
          NEXTAUTH_URL = "https://${cfg.subdomain}.${cfg.domain}";
          OAUTH_WELLKNOWN_URL = "${cfg.sso.authEndpoint}/.well-known/openid-configuration";
          OAUTH_PROVIDER_NAME = "Single Sign-On";
          OAUTH_CLIENT_ID = cfg.sso.clientID;
          OAUTH_SCOPE = "openid email profile";
        };
        environmentFile = "/run/karakeep/secrets.env";
      };

      systemd.tmpfiles.rules = [
        "d '/run/karakeep' 0750 root root - -"
      ];
      systemd.services.karakeep-pre = {
        script = lib.shb.replaceSecrets {
          userConfig = {
            NEXTAUTH_SECRET.source = cfg.sso.nextauthSecret.result.path;
            OAUTH_CLIENT_SECRET.source = cfg.sso.sharedSecret.result.path;
          };
          resultPath = "/run/karakeep/secrets.env";
          generator = lib.shb.toEnvVar;
        };
        serviceConfig.Type = "oneshot";
        wantedBy = [ "multi-user.target" ];
        before = [ "karakeep-web.service" "karakeep-workers.service" ];
        requiredBy = [ "karakeep-web.service" "karakeep-workers.service" ];
      };
    })
  ]);
}