import { CreateFontCommand } from '../core/commands/assetCommands';
import type { FontStore, UploadedFont } from '../core/store/FontStore';
import { type ImportKind, type ImportOutcome, importFiles, importStored, pickAndImport } from './assetImport';
import type { EditorState } from './state';

/** What the file dialog offers and a drop accepts; the server rejects everything else anyway. */
export const FONT_ACCEPT = '.ttf,.otf,.woff,.woff2';

const FONT_EXTENSION = /\.(ttf|otf|woff|woff2)$/i;

/**
 * Fonts are told apart by their name, not their MIME type: browsers report a dropped `.ttf` as
 * `font/ttf`, `application/x-font-ttf` or nothing at all, depending on the platform.
 */
export function isFontFileName(name: string): boolean {
  return FONT_EXTENSION.test(name);
}

export interface FontImportDeps {
  state: EditorState;
  fonts: FontStore;
}

const FONT_KIND: ImportKind<UploadedFont, FontImportDeps> = {
  type: 'font',
  noun: 'font',
  fallbackName: 'Font',
  store: (deps) => deps.fonts,
  // The bytes go up untouched: unlike a picture, a typeface cannot be re-encoded smaller here.
  prepare: (file) =>
    isFontFileName(file.name)
      ? Promise.resolve({ blob: file, type: file.type || 'application/octet-stream' })
      : Promise.reject(new Error('Not a font file – use TTF, OTF, WOFF or WOFF2.')),
  create: (name, font) => new CreateFontCommand(name, font.file),
};

export function importFonts(files: readonly File[], deps: FontImportDeps): Promise<ImportOutcome[]> {
  return importFiles(FONT_KIND, files, deps);
}

export function importStoredFont(font: UploadedFont, deps: FontImportDeps): ImportOutcome {
  return importStored(FONT_KIND, font, deps);
}

export function pickAndImportFonts(deps: FontImportDeps): void {
  pickAndImport(FONT_KIND, FONT_ACCEPT, deps);
}