import { TokenTags, parseTags } from "../language/tags.ts";

declare global {
	interface String {
		/** @summary get UnicodeRange for character at index 0 */
		range(): UnicodeRange;
		/** @summary create a RangeTally object for counting used unicode ranges in string */
		rangeTally(): RangeTally;

		/** @summary parse concatenated tag string to TokenTags */
		parseTags(): TokenTags;

		/**
		 * @summary Remove all instances of a substring in a string, using a regular expression or search string
		 * @param searchValue  A string to search for
		 */
		removeAll(searchValue: string | RegExp): string;

		/**
		 * @summary parse string as JSON, with optional fallback value
		 *
		 * fallback is undefined by default. if fallback is specified, it will be
		 * returned if JSON.parse throws any error. if fallback is not specified,
		 * no errors will be caught.
		 *
		 * @argument fallback  return this value if parsing fails
		 */
		json(fallback?: any): any;
	}
}

export enum UnicodeRange {
	BasicLatin = "latin",
	Whitespace = "any-whitespace",
	Punctuation = "any-punctuation",
	Unknown = "any-unknown",
	JapanesePunctuation = "jp-punctuation",
	JapaneseHiragana = "jp-hiragana",
	JapaneseKatakana = "jp-katakana",
	JapaneseFWLatinHWKatakana = "jp-full-width-latin-half-width-katakana",
	JapaneseKanji = "jp-kanji",
}

type RangeTally = Record<UnicodeRange, number>;

String.prototype.range = function() {
	var code = this.charCodeAt(0);

	if (0x09 == code) return UnicodeRange.Whitespace; // tab
	if (0x20 == code) return UnicodeRange.Whitespace; // space
	if (0x21 == code) return UnicodeRange.Punctuation; // exclamation mark
	if (0x2e == code) return UnicodeRange.Punctuation; // full stop
	if (0x3f == code) return UnicodeRange.Punctuation; // question mark

	if (0x0000 <= code && code <= 0x007f) return UnicodeRange.BasicLatin;
	if (0x3000 <= code && code <= 0x303f) return UnicodeRange.JapanesePunctuation;
	if (0x3040 <= code && code <= 0x309f) return UnicodeRange.JapaneseHiragana;
	if (0x30a0 <= code && code <= 0x30ff) return UnicodeRange.JapaneseKatakana;
	if (0xff00 <= code && code <= 0xffef) return UnicodeRange.JapaneseFWLatinHWKatakana;
	if (0x4e00 <= code && code <= 0x9faf) return UnicodeRange.JapaneseKanji;
	return UnicodeRange.Unknown;
}

String.prototype.rangeTally = function() {
	var tally = Object.keys(UnicodeRange).reduce((a: any,c) => (a[c] = 0, a), {}) as RangeTally;
	for (var char of this) tally[char.range()]++;
	return tally;
};

String.prototype.parseTags = function() {
	return parseTags(this as string);
}

String.prototype.removeAll = function(searchValue: string | RegExp) {
	return this.replaceAll(searchValue, "");
}

String.prototype.json = function(fallback?: any) {
	if (fallback) {
		try {
			return JSON.parse(this as string);
		} catch {
			return fallback;
		}
	} else {
		return JSON.parse(this as string);
	}
}