/* eslint-disable no-console */
import { cyanBright, red } from 'chalk';
import { execSync } from 'child_process';

/** A single item as returned by `bw list items`. */
interface BitwardenItem {
  name: string;
  login?: {
    username: string;
    password: string;
  };
  fields?: [
    {
      name: string;
      value: string;
    },
  ];
}

/** Interface for a vault which provides values. */
export interface Vault {
  error: string | undefined;
  getValue(name: string, fieldName: string): string | undefined;
}

/** Represents a Bitwarden vault accessed through Bitwarden CLI commands. */
export class BitwardenVault implements Vault {
  constructor(private serverUrl: string | undefined) {
    this.error = this.sync();
    if (!this.error) {
      this.items = this.fetchItems();
    }
  }
  /** If there is an error getting items from the vault this will not be undefined. */
  public error: string | undefined;

  private readonly items: BitwardenItem[] | undefined;

  /** Get a value from the vault. If the value is not found returns undefined. */
  public getValue(name: string, fieldName: string): string | undefined {
    for (const item of this.items ?? []) {
      if (item.name === name) {
        if (item.login && fieldName === 'username') {
          return item.login.username;
        }
        if (item.login && fieldName === 'password') {
          return item.login.password;
        }
        if (item.fields) {
          for (const field of item.fields) {
            if (field.name === fieldName) {
              return field.value;
            }
          }
        }
      }
    }
    return undefined;
  }

  /**
   * Syncs the Bitwarden vault. Note: this only downloads data.
   *
   * We could make this more interactive:
   * - Get status ('yarn bw status') and parse it
   * - Set server url automatically if its not set. Fail with error if it is set but different
   * - Prompt for username & password if not logged in. Login and store session id in memory
   * - Prompt for password if locked. Unlock and store session id in memory
   * - Session id can then be passed to `sync` & `list items` commands with --session
   * Reasons to not do this:
   * - The script becomes more complex
   * - Additional security concern of handling password entry
   * - Password would need to be entered every time the script is run (rather than just once per terminal session)
   * - Blocker: unlocked status is not reported correctly: https://github.com/bitwarden/clients/issues/2729. This
   *   makes it really hard to determine the correct course of action.
   */
  private sync(): string | undefined {
    try {
      execSync(`yarn bw --nointeraction sync`);
      console.log(`Bitwarden vault synced.`);
      return undefined;
    } catch (e) {
      console.log();
      // Try to determine what is the issue and provide some direction
      if (e instanceof Error && e.message.includes('getaddrinfo ENOTFOUND')) {
        return 'The Bitwarden server could not be found. Do you need to connect to the VPN?';
      }
      if (e instanceof Error && e.message.includes('You are not logged in')) {
        return this.serverUrl !== undefined
          ? 'You are not logged in. Run command `' +
              cyanBright(`yarn bw config server ${this.serverUrl}`) +
              '` to set the server url, then command `' +
              cyanBright('yarn bw login') +
              '` and follow the instructions to unlock your vault.'
          : 'You are not logged in. Run command `' +
              cyanBright('yarn bw login') +
              '` and follow the instructions to unlock your vault.';
      }
      if (e instanceof Error && e.message.includes('Vault is locked')) {
        return (
          'Your vault is locked. Do you need to connect to the VPN? Run command `' +
          cyanBright('yarn bw unlock') +
          '` and follow the instructions to unlock your vault.'
        );
      }
      return (
        'Unexpected error syncing Bitwarden vault. You may need to run command `' +
        cyanBright('yarn install') +
        '` to install the Bitwarden CLI otherwise use command `' +
        cyanBright('yarn bw status') +
        '` to show the full status.'
      );
    }
  }

  /**
   * Gets Bitwarden collection items from the vault.
   */
  private fetchItems(): BitwardenItem[] {
    try {
      const json = execSync(
        'yarn run --silent bw --nointeraction list items',
      ).toString();
      return JSON.parse(json) as BitwardenItem[];
    } catch (_e) {
      console.log();
      console.error(red('ERROR: Could not list items in the vault.'));
      process.exit(1);
    }
  }
}