import * as plugins from './smartssh.plugins.js';
import * as helpers from './smartssh.classes.helpers.js';
import { SshKey } from './smartssh.classes.sshkey.js';

export type TSshStrictHostKeyChecking = boolean | 'accept-new';

export interface ISshConfigOptions {
  strictHostKeyChecking?: TSshStrictHostKeyChecking;
}

export interface ISshConfigHostBlock {
  host: string;
  values: Record<string, string>;
}

export class SshConfig {
  private _sshKeyArray: SshKey[];
  private _options: ISshConfigOptions;
  constructor(sshKeyArrayArg: SshKey[], optionsArg: ISshConfigOptions = {}) {
    this._sshKeyArray = sshKeyArrayArg;
    this._options = {
      ...optionsArg,
      strictHostKeyChecking: optionsArg.strictHostKeyChecking ?? true,
    };
  }

  /**
   * stores a config file
   */
  store(dirPathArg: string) {
    const resolvedDir = helpers.resolveSshDirPath(dirPathArg);
    helpers.ensureSshDirSync(resolvedDir);
    const configArray: configObject[] = [];
    for (const sshKey of this._sshKeyArray) {
      let configString = '';
      if (sshKey.host) {
        helpers.assertSafeHost(sshKey.host);
        const identityFilePath = plugins.path.join(resolvedDir, sshKey.host);
        configString =
          'Host ' +
          sshKey.host +
          '\n' +
          '  HostName ' +
          sshKey.host +
          '\n' +
          '  IdentityFile ' +
          helpers.quoteSshConfigValue(identityFilePath) +
          '\n';
        if (this._options.strictHostKeyChecking !== undefined) {
          const strictHostKeyChecking = this._options.strictHostKeyChecking;
          configString +=
            '  StrictHostKeyChecking ' +
            (strictHostKeyChecking === 'accept-new'
              ? 'accept-new'
              : strictHostKeyChecking
                ? 'yes'
                : 'no') +
            '\n';
        }
      }
      configArray.push({
        configString: configString,
        authorized: sshKey.authorized,
        sshKey: sshKey,
      });
    }
    let configFile: string = '';
    for (const config of configArray) {
      configFile = configFile + config.configString + '\n';
    }
    plugins.fs.writeFileSync(plugins.path.join(resolvedDir, 'config'), configFile);
    plugins.fs.chmodSync(plugins.path.join(resolvedDir, 'config'), 0o600);
  }
  read(dirPathArg: string) {
    const configPath = plugins.path.join(helpers.resolveSshDirPath(dirPathArg), 'config');
    return plugins.fs.readFileSync(configPath, 'utf8');
  }

  parse(dirPathArg: string) {
    return SshConfig.parse(this.read(dirPathArg));
  }

  static parse(configStringArg: string): ISshConfigHostBlock[] {
    const blocks: ISshConfigHostBlock[] = [];
    let currentBlock: ISshConfigHostBlock | undefined;

    for (const rawLine of configStringArg.split(/\r?\n/)) {
      const line = rawLine.trim();
      if (!line || line.startsWith('#')) {
        continue;
      }

      const [keyword, ...valueParts] = line.split(/\s+/);
      const value = valueParts.join(' ');
      if (!keyword || !value) {
        continue;
      }

      if (keyword.toLowerCase() === 'host') {
        if (!helpers.isSafeHost(value)) {
          continue;
        }
        currentBlock = {
          host: value,
          values: {},
        };
        blocks.push(currentBlock);
        continue;
      }

      if (currentBlock) {
        currentBlock.values[keyword.toLowerCase()] = value;
      }
    }

    return blocks;
  }
}

export interface configObject {
  configString: string;
  authorized: boolean;
  sshKey: SshKey;
}