gopher_item.ts

import {CRLF} from './gopher_common.ts';
import {ItemType, UnknownType} from './gopher_types.ts';

/** Contains all of the Gopher+ attributes for a GopherItem. */
export class ItemAttributes {
  /** The name of the block, e.g. `INFO`, `VIEWS` etc. No leading `+`. */
  name: string = '';
  /** The attribute block dedscriptor - e.g. `+INFO: <descriptor goes here>`. */
  descriptor!: string;
  /** 
   * The lines of the attribute block. This is typically treated as key values,
   * but may just be strings, so we have both the raw string block and a map
   * for convenience.
   */
  rawLines: string = '';
  lines: Map<string, string> = new Map<string, string>();
}

/** Represents an item in a Gopher menu. */
export abstract class GopherItem {
  /** The type of this menu item - e.g. 'i' or '1' etc. */
  type: ItemType = new UnknownType('?');
  
  /**
   * The name or description of this item. Typically this is the user-visible
   * part of the menu item that is shown in Gopher clients.
   */
  name: string = '';
  
  /** Menu selector itself, e.g. `/foo` */
  selector: string = 'fake';
  
  /** Hostname */
  hostname: string = '';
  
  /** Port number. */
  port: number = 0;  
  
  /** Flag inidicating if this item supports Gopher+ */
  gopherPlus: boolean = false;
  
  /** Original raw string for this item. */
  original: string = '';

  /** Gopher+ Attribute map for this item. May not be populated. */
  attributes: Map<string, ItemAttributes> = new Map<string, ItemAttributes>();

  /** Parses a string and converts it to attributes. */
  parseAttributes(rawAttributesString:string) {
    // Spec does not say if attributes should be CRLF or just LF?
    let lines = rawAttributesString.split(`\n`);
    // Shift off the first line (the Gopher+ status) since we don't care.
    lines.shift();
    if (!lines) return;
    let lastAttribute = '';
    for (const line of lines) {
      const separator = line.indexOf(':');
      if (line.startsWith('+')) {
        const attributeName = line.substring(1, separator);
        const descriptor = line.substring(separator + 1).trim();
        const attr = new ItemAttributes();
        attr.name = attributeName;
        attr.descriptor = descriptor;
        this.attributes.set(attributeName, attr);
        lastAttribute = attributeName;
      } else {
        if (!lastAttribute) continue;
        this.attributes.get(lastAttribute)!.rawLines += `${line}${CRLF}`;
        const key = line.substring(0, separator).trim();
        const value = line.substring(separator + 1).trim();
        if (!key || !value) continue;
        this.attributes.get(lastAttribute)!.lines.set(key, value);
      }
    }
  }
}