import * as plugins from './npmextra.plugins.js';
import * as paths from './npmextra.paths.js';
import { KeyValueStore } from './npmextra.classes.keyvaluestore.js';

export interface IAppDataOptions<T = any> {
  dirPath?: string;
  requiredKeys?: Array<keyof T>;

  /**
   * wether keys should be persisted on disk or not
   */
  ephermal?: boolean;

  /**
   * kvStoreKey: 'MY_ENV_VAR'
   */
  envMapping?: plugins.tsclass.typeFest.PartialDeep<T>;
  overwriteObject?: plugins.tsclass.typeFest.PartialDeep<T>;
}

export class AppData<T = any> {
  /**
   * creates appdata. If no pathArg is given, data will be stored here:
   * ${PWD}/.nogit/appdata
   * @param pathArg
   * @returns
   */
  public static async createAndInit<T = any>(
    optionsArg: IAppDataOptions<T> = {}
  ): Promise<AppData<T>> {
    const appData = new AppData<T>(optionsArg);
    await appData.readyDeferred.promise;
    return appData;
  }

  // instance
  public readyDeferred = plugins.smartpromise.defer<void>();
  public options: IAppDataOptions<T>;
  private kvStore: KeyValueStore<T>;

  constructor(optionsArg: IAppDataOptions<T> = {}) {
    this.options = optionsArg;
    this.init();
  }

  /**
   * inits app data
   * @param pathArg
   */
  private async init(pathArg?: string) {
    if (this.options.dirPath || this.options.ephermal) {
      // ok, nothing to do here;
    } else {
      const appDataDir = '/app/data';
      const dataDir = '/data';
      const nogitAppData = '.nogit/appdata';
      const appDataExists = plugins.smartfile.fs.isDirectory(appDataDir);
      const dataExists = plugins.smartfile.fs.isDirectory(dataDir);
      if (appDataExists) {
        this.options.dirPath = appDataDir;
      } else if (dataExists) {
        this.options.dirPath = dataDir;
      } else {
        await plugins.smartfile.fs.ensureDir(nogitAppData);
        this.options.dirPath = nogitAppData;
      }
    }

    this.kvStore = new KeyValueStore<T>({
      typeArg: this.options.ephermal ? 'ephemeral' : 'custom',
      identityArg: 'appkv',
      customPath: this.options.dirPath,
      mandatoryKeys: this.options.requiredKeys as Array<keyof T>,
    });

    if (this.options.envMapping) {
      const qenvInstance = new plugins.qenv.Qenv(
        process.cwd(),
        plugins.path.join(process.cwd(), '.nogit')
      );

      // Recursive function to handle nested objects, now includes key parameter
      const processEnvMapping = async (
        key: keyof T,
        mappingValue: any,
        parentKey: keyof T | '' = ''
      ): Promise<any> => {
        if (typeof mappingValue === 'string') {
          let envValue: string | boolean | T[keyof T];
          let convert: 'none' | 'json' | 'base64' | 'boolean' = 'none';
          switch (true) {
            case mappingValue.startsWith('hard:'):
              envValue = mappingValue.replace('hard:', '') as T[keyof T];
              break;
            case mappingValue.startsWith('hard_boolean:'):
              envValue = mappingValue.replace('hard_boolean:', '') === 'true';
              convert = 'boolean';
              break;
            case mappingValue.startsWith('hard_json:'):
              envValue = JSON.parse(mappingValue.replace('hard_json:', '')) as T[keyof T];
              convert = 'json';
              break;
            case mappingValue.startsWith('hard_base64:'):
              envValue = Buffer.from(
                mappingValue.replace('hard_base64:', ''),
                'base64'
              ).toString() as T[keyof T];
              convert = 'base64';
              break;
            case mappingValue.startsWith('boolean:'):
              envValue = (await qenvInstance.getEnvVarOnDemand(
                mappingValue.replace('boolean:', '')
              )) as T[keyof T];
              convert = 'boolean';
              break;
            case mappingValue.startsWith('json:'):
              envValue = (await qenvInstance.getEnvVarOnDemand(
                mappingValue.replace('json:', '')
              )) as T[keyof T];
              convert = 'json';
              break;
            case mappingValue.startsWith('base64:'):
              envValue = (await qenvInstance.getEnvVarOnDemand(
                mappingValue.replace('base64:', '')
              )) as T[keyof T];
              convert = 'base64';
              break;
            default:
              envValue = (await qenvInstance.getEnvVarOnDemand(mappingValue)) as T[keyof T];
              break;
          }

          // lets format the env value
          if (envValue) {
            if (typeof envValue === 'string' && convert === 'boolean') {
              envValue = envValue === 'true';
            }
            if (
              typeof envValue === 'string' &&
              (mappingValue.endsWith('_JSON') || convert === 'json')
            ) {
              envValue = JSON.parse(envValue as string) as T[keyof T];
            }
            if (
              typeof envValue === 'string' &&
              (mappingValue.endsWith('_BASE64') || convert === 'base64')
            ) {
              envValue = Buffer.from(envValue as string, 'base64').toString();
            }
            if (!parentKey) {
              await this.kvStore.writeKey(key, envValue as any);
            } else {
              return envValue;
            }
          } else {
            return undefined;
          }
        } else if (typeof mappingValue === 'object' && mappingValue !== null) {
          const resultObject: Partial<T> = {};
          for (const innerKey in mappingValue) {
            const nestedValue = mappingValue[innerKey];
            // For nested objects, call recursively but do not immediately write to kvStore
            const nestedResult = await processEnvMapping(innerKey as keyof T, nestedValue, key);
            resultObject[innerKey as keyof T] = nestedResult;
          }
          if (parentKey === '') {
            // Only write to kvStore if at the top level
            await this.kvStore.writeKey(key, resultObject as T[keyof T]);
          } else {
            // For nested objects, return the constructed object instead of writing to kvStore
            return resultObject;
          }
        }
      };

      for (const key in this.options.envMapping) {
        await processEnvMapping(key as keyof T, this.options.envMapping[key]);
      }

      if (this.options.overwriteObject) {
        for (const key of Object.keys(this.options.overwriteObject)) {
          console.log(`-> heads up: overwriting key ${key} from options.overwriteObject`);
          await this.kvStore.writeKey(key as keyof T, this.options.overwriteObject[key]);
        }
      }
    }

    this.readyDeferred.resolve();
  }

  /**
   * returns a kvstore that resides in appdata
   */
  public async getKvStore(): Promise<KeyValueStore<T>> {
    await this.readyDeferred.promise;
    return this.kvStore;
  }

  public async logMissingKeys(): Promise<Array<keyof T>> {
    const kvStore = await this.getKvStore();
    const missingMandatoryKeys = await kvStore.getMissingMandatoryKeys();
    if (missingMandatoryKeys.length > 0) {
      console.log(
        `The following mandatory keys are missing in the appdata:\n   -> ${missingMandatoryKeys.join(
          ',\n   -> '
        )}`
      );
    } else {
      console.log('All mandatory keys are present in the appdata');
    }
    return missingMandatoryKeys;
  }

  public async waitForAndGetKey<K extends keyof T>(keyArg: K): Promise<T[K] | undefined> {
    await this.readyDeferred.promise;
    await this.kvStore.waitForKeysPresent([keyArg]);
    return this.kvStore.readKey(keyArg);
  }
}