package auth.sso;

import static auth.AuthUtils.*;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

/**
 * Class responsible for extracting and validating top-level SSO related configurations. TODO:
 * Refactor SsoConfigs to have OidcConfigs and other identity provider specific configs as instance
 * variables. SSoManager should ideally not know about identity provider specific configs.
 */
public class SsoConfigs {

  /** Required configs */
  private static final String AUTH_BASE_URL_CONFIG_PATH = "auth.baseUrl";

  private static final String AUTH_BASE_CALLBACK_PATH_CONFIG_PATH = "auth.baseCallbackPath";
  private static final String AUTH_SUCCESS_REDIRECT_PATH_CONFIG_PATH = "auth.successRedirectPath";
  public static final String OIDC_ENABLED_CONFIG_PATH = "auth.oidc.enabled";

  /** Default values */
  private static final String DEFAULT_BASE_CALLBACK_PATH = "/callback";

  private static final String DEFAULT_SUCCESS_REDIRECT_PATH = "/";

  private final String authBaseUrl;
  private final String authBaseCallbackPath;
  private final String authSuccessRedirectPath;
  private final Boolean oidcEnabled;

  public SsoConfigs(Builder<?> builder) {
    authBaseUrl = builder.authBaseUrl;
    authBaseCallbackPath = builder.authBaseCallbackPath;
    authSuccessRedirectPath = builder.authSuccessRedirectPath;
    oidcEnabled = builder.oidcEnabled;
  }

  public String getAuthBaseUrl() {
    return authBaseUrl;
  }

  public String getAuthBaseCallbackPath() {
    return authBaseCallbackPath;
  }

  public String getAuthSuccessRedirectPath() {
    return authSuccessRedirectPath;
  }

  public Boolean isOidcEnabled() {
    return oidcEnabled;
  }

  public static class Builder<T extends Builder<T>> {
    protected String authBaseUrl = null;
    private String authBaseCallbackPath = DEFAULT_BASE_CALLBACK_PATH;
    private String authSuccessRedirectPath = DEFAULT_SUCCESS_REDIRECT_PATH;
    protected Boolean oidcEnabled = false;
    private final ObjectMapper objectMapper = new ObjectMapper();
    protected JsonNode jsonNode = null;

    // No need to check if changes are made since this method is only called at start-up.
    public Builder from(final com.typesafe.config.Config configs) {
      if (configs.hasPath(AUTH_BASE_URL_CONFIG_PATH)) {
        authBaseUrl = configs.getString(AUTH_BASE_URL_CONFIG_PATH);
      }
      if (configs.hasPath(AUTH_BASE_CALLBACK_PATH_CONFIG_PATH)) {
        authBaseCallbackPath = configs.getString(AUTH_BASE_CALLBACK_PATH_CONFIG_PATH);
      }
      if (configs.hasPath(OIDC_ENABLED_CONFIG_PATH)) {
        oidcEnabled =
            Boolean.TRUE.equals(Boolean.parseBoolean(configs.getString(OIDC_ENABLED_CONFIG_PATH)));
      }
      if (configs.hasPath(AUTH_SUCCESS_REDIRECT_PATH_CONFIG_PATH)) {
        authSuccessRedirectPath = configs.getString(AUTH_SUCCESS_REDIRECT_PATH_CONFIG_PATH);
      }
      return this;
    }

    public Builder from(String ssoSettingsJsonStr) {
      try {
        jsonNode = objectMapper.readTree(ssoSettingsJsonStr);
      } catch (Exception e) {
        throw new RuntimeException(
            String.format("Failed to parse ssoSettingsJsonStr %s into JSON", ssoSettingsJsonStr));
      }
      if (jsonNode.has(BASE_URL)) {
        authBaseUrl = jsonNode.get(BASE_URL).asText();
      }
      if (jsonNode.has(OIDC_ENABLED)) {
        oidcEnabled = jsonNode.get(OIDC_ENABLED).asBoolean();
      }

      return this;
    }

    public SsoConfigs build() {
      return new SsoConfigs(this);
    }
  }
}