import { CloudlyAdapter } from './qenv.classes.configvaultadapter.js';
import * as plugins from './qenv.plugins.js';

export type TEnvVarRef = string | (() => Promise<string>);

export class Qenv {
  public requiredEnvVars: string[] = [];
  public availableEnvVars: string[] = [];
  public missingEnvVars: string[] = [];
  public keyValueObject: { [key: string]: any } = {};
  public logger = new plugins.smartlog.ConsoleLog();

  public cloudlyAdapter: CloudlyAdapter;

  public qenvFilePathAbsolute: string;
  public envFilePathAbsolute: string;

  constructor(
    qenvFileBasePathArg: string = process.cwd(),
    envFileBasePathArg?: string,
    failOnMissing: boolean = true
  ) {
    this.cloudlyAdapter = new CloudlyAdapter();
    this.initializeFilePaths(qenvFileBasePathArg, envFileBasePathArg);
    this.loadRequiredEnvVars();
    this.loadAvailableEnvVars();
    this.checkForMissingEnvVars(failOnMissing);
  }

  private initializeFilePaths(qenvFileBasePathArg: string, envFileBasePathArg: string) {
    this.qenvFilePathAbsolute = plugins.path.join(
      plugins.path.resolve(qenvFileBasePathArg),
      'qenv.yml'
    );
    if (envFileBasePathArg) {
      this.envFilePathAbsolute = plugins.path.join(
        plugins.path.resolve(envFileBasePathArg),
        'env.json'
      );
    }
  }

  private loadRequiredEnvVars() {
    if (plugins.smartfile.fs.fileExistsSync(this.qenvFilePathAbsolute)) {
      const qenvFile = plugins.smartfile.fs.toObjectSync(this.qenvFilePathAbsolute);
      if (qenvFile?.required && Array.isArray(qenvFile.required)) {
        this.requiredEnvVars.push(...qenvFile.required);
      } else {
        this.logger.log('warn', 'qenv.yml does not contain a "required" Array!');
      }
    }
  }

  private loadAvailableEnvVars() {
    for (const envVar of this.requiredEnvVars) {
      const value = this.getEnvVarOnDemand(envVar);
      if (value) {
        this.availableEnvVars.push(envVar);
        this.keyValueObject[envVar] = value;
      }
    }
  }

  private checkForMissingEnvVars(failOnMissing: boolean) {
    this.missingEnvVars = this.requiredEnvVars.filter(
      (envVar) => !this.availableEnvVars.includes(envVar)
    );

    if (this.missingEnvVars.length > 0) {
      console.info('Required Env Vars are:', this.requiredEnvVars);
      console.error('Missing Env Vars:', this.missingEnvVars);
      if (failOnMissing) {
        this.logger.log('error', 'Exiting due to missing env vars!');
        process.exit(1);
      } else {
        this.logger.log('warn', 'qenv is not set to fail on missing environment variables');
      }
    }
  }

  public async getEnvVarOnDemand(
    envVarNameOrNames: TEnvVarRef | TEnvVarRef[]
  ): Promise<string | undefined> {
    if (Array.isArray(envVarNameOrNames)) {
      for (const envVarName of envVarNameOrNames) {
        const value = await this.tryGetEnvVar(envVarName);
        if (value) {
          return value;
        }
      }
      return undefined;
    } else {
      return await this.tryGetEnvVar(envVarNameOrNames);
    }
  }

  public getEnvVarOnDemandSync(envVarNameOrNames: string | string[]): string | undefined {
    console.warn('requesting env var sync leaves out potentially important async env sources.');

    if (Array.isArray(envVarNameOrNames)) {
      for (const envVarName of envVarNameOrNames) {
        const value = this.tryGetEnvVarSync(envVarName);
        if (value) {
          return value;
        }
      }
      return undefined;
    } else {
      return this.tryGetEnvVarSync(envVarNameOrNames);
    }
  }

  public async getEnvVarOnDemandAsObject(envVarNameOrNames: string | string[]): Promise<any> {
    const rawValue = await this.getEnvVarOnDemand(envVarNameOrNames);
    if (rawValue && rawValue.startsWith('base64Object:')) {
      const base64Part = rawValue.split('base64Object:')[1];
      return this.decodeBase64(base64Part);
    }
    return rawValue;
  }

  private async tryGetEnvVar(envVarRefArg: TEnvVarRef): Promise<string | undefined> {
    if (typeof envVarRefArg === 'function') {
      return await envVarRefArg();
    }

    return (
      this.getFromEnvironmentVariable(envVarRefArg) ||
      this.getFromEnvJsonFile(envVarRefArg) ||
      this.getFromDockerSecret(envVarRefArg) ||
      this.getFromDockerSecretJson(envVarRefArg)
    );
  }

  private tryGetEnvVarSync(envVarName: string): string | undefined {
    return (
      this.getFromEnvironmentVariable(envVarName) ||
      this.getFromEnvJsonFile(envVarName) ||
      this.getFromDockerSecret(envVarName) ||
      this.getFromDockerSecretJson(envVarName)
    );
  }

  private getFromEnvironmentVariable(envVarName: string): string | undefined {
    return process.env[envVarName];
  }

  private getFromEnvJsonFile(envVarName: string): string | undefined {
    if (!plugins.smartfile.fs.fileExistsSync(this.envFilePathAbsolute)) {
      return undefined;
    }
    try {
      const envJson = plugins.smartfile.fs.toObjectSync(this.envFilePathAbsolute);
      const value = envJson[envVarName];
      if (typeof value === 'object') {
        return 'base64Object:' + this.encodeBase64(value);
      }
      return value;
    } catch (error) {
      return undefined;
    }
  }

  private getFromDockerSecret(envVarName: string): string | undefined {
    const secretPath = `/run/secrets/${envVarName}`;
    if (plugins.smartfile.fs.fileExistsSync(secretPath)) {
      return plugins.smartfile.fs.toStringSync(secretPath);
    }
    return undefined;
  }

  private getFromDockerSecretJson(envVarName: string): string | undefined {
    if (plugins.smartfile.fs.isDirectory('/run/secrets')) {
      const availableSecrets = plugins.smartfile.fs.listAllItemsSync('/run/secrets');
      for (const secret of availableSecrets) {
        if (secret.includes('secret.json')) {
          const secretObject = plugins.smartfile.fs.toObjectSync(`/run/secrets/${secret}`);
          const value = secretObject[envVarName];
          if (typeof value === 'object') {
            return 'base64Object:' + this.encodeBase64(value);
          }
          return value;
        }
      }
    }
    return undefined;
  }

  private encodeBase64(data: any): string {
    const jsonString = JSON.stringify(data);
    return Buffer.from(jsonString).toString('base64');
  }

  private decodeBase64(encodedString: string): any {
    const decodedString = Buffer.from(encodedString, 'base64').toString('utf-8');
    return JSON.parse(decodedString);
  }
}