malice

import type { PackTarget } from './transport';

import type { ImagePack, ImagePacks, PackImage, PackUsage } from './types';

export interface PackChoice {

  label: string;

  target: PackTarget;

  pack: ImagePack | null;

}

export function packTarget(pack: ImagePack): PackTarget {

  if (pack.source === 'User') return { kind: 'user' };

  return { kind: 'room', room_id: pack.source.Room.room_id, state_key: pack.source.Room.state_key };

}

export function packLabel(pack: ImagePack, roomName: (roomId: string) => string): string {

  if (pack.display_name) return pack.display_name;

  if (pack.source === 'User') return 'Your pack';

  return roomName(pack.source.Room.room_id);

}

export function allPacks(packs: ImagePacks): ImagePack[] {

  const seen = new Set<string>();

  const out: ImagePack[] = [];

  for (const pack of [...packs.global, ...Object.values(packs.rooms).flat()]) {

    if (seen.has(pack.id)) continue;

    seen.add(pack.id);

    out.push(pack);

  }

  return out;

}

/** Packs you can write to, with your own pack first even before it exists. */

export function editableChoices(packs: ImagePacks, roomName: (roomId: string) => string): PackChoice[] {

  const all = allPacks(packs);

  const user = all.find((p) => p.source === 'User') ?? null;

  const choices: PackChoice[] = [{ label: user?.display_name ?? 'Your pack', target: { kind: 'user' }, pack: user }];

  for (const pack of all) {

    if (pack.source === 'User' || !pack.editable) continue;

    choices.push({ label: packLabel(pack, roomName), target: packTarget(pack), pack });

  }

  return choices;

}

export function hasUsage(image: PackImage, usage: PackUsage): boolean {

  return image.usage.length === 0 || image.usage.includes(usage);

}

export function stickersOf(pack: ImagePack): PackImage[] {

  return pack.images.filter((image) => hasUsage(image, 'Sticker'));

}

/** A shortcode from a file name, unique within `taken`. */

export function shortcodeFor(filename: string, taken: Set<string>): string {

  const stem = filename.replace(/\.[^.]+$/, '');

  const base =

    stem

      .toLowerCase()

      .replace(/[^a-z0-9_-]+/g, '_')

      .replace(/^_+|_+$/g, '')

      .slice(0, 64) || 'image';

  let candidate = base;

  for (let n = 2; taken.has(candidate); n += 1) candidate = `${base}_${n}`;

  taken.add(candidate);

  return candidate;

}

export function validShortcode(code: string): boolean {

  return /^[^\s:]{1,100}$/.test(code);

}

export function packSlug(name: string): string {

  return (

    name

      .toLowerCase()

      .replace(/[^a-z0-9]+/g, '-')

      .replace(/^-+|-+$/g, '')

      .slice(0, 48) || 'pack'

  );

}

export interface CloneDestination {

  label: string;

  target: PackTarget;

  display_name: string | null;

}

/** Where a whole pack can be cloned to: merged into your pack, or as a new pack in a room you can edit. */

export function clonePackDestinations(

  pack: ImagePack,

  rooms: { room_id: string; name: string }[],

  roomName: (roomId: string) => string

): CloneDestination[] {

  const name = packLabel(pack, roomName);

  return [

    { label: 'Merge into your pack', target: { kind: 'user' }, display_name: null },

    ...rooms.map((room) => ({

      label: `New pack in ${room.name}`,

      target: { kind: 'room', room_id: room.room_id, state_key: packSlug(name) } as PackTarget,

      display_name: name

    }))

  ];

}