#!/usr/bin/env node;
/******************************************************************************
 * This program demonstrates basic string functions.
 * 
 * Copyright © 2020 Richard Lesh.  All rights reserved.
 *****************************************************************************/

const Utils = require('./Utils');

const main = async () => {
	const alphabet = "abcdefghijklmnopqrstuvwxyzabc";
	const greekAlphabet = "αβγδεζηθικλμνξοπρσςτυφχψωαβγ";
	const emoji = "😃😇🥰🤪🤑😴🤒🥵🥶🤯🥳😎😥😱😡🤬💀👽🤖😺🙈🙉🙊😃😇🥰";

	console.log("Length: " + Utils.cpLength(alphabet));
	console.log("charAt(17): " + Utils.uniAt(alphabet, 17));
	console.log("codePointAt(17): " + Utils.cpAt(alphabet, 17));
	console.log("substr(23, 26): " + Utils.cpSubstr(alphabet, 23, 3));
	console.log("prefix(6): " + Utils.cpSubstr(alphabet, 0, 6));
	console.log("right_tail(6): " + Utils.cpSubstr(alphabet, 6));
	console.log("suffix(6): " + Utils.cpSubstr(alphabet, Utils.cpLength(alphabet) - 6));
	console.log("find(\'def\'): " + Utils.cpIndexOf(alphabet, "def"));
	console.log("find(\'def\') is not found: " + (Utils.cpIndexOf(alphabet, "def") === -1));
	console.log("find(\'bug\'): " + Utils.cpIndexOf(alphabet, "bug"));
	console.log("find(\'bug\') is not found: " + (Utils.cpIndexOf(alphabet, "bug") === -1));
	console.log("rfind(\'abc\'): " + Utils.cpLastIndexOf(alphabet, "abc"));
	console.log("rfind(\'abc\') is not found: " + (Utils.cpLastIndexOf(alphabet, "abc") === -1));
	console.log("rfind(\'bug\'): " + Utils.cpLastIndexOf(alphabet, "bug"));
	console.log("rfind(\'bug\') is not found: " + (Utils.cpLastIndexOf(alphabet, "bug") === -1));

	console.log("Length: " + Utils.cpLength(greekAlphabet));
	console.log("charAt(17): " + Utils.uniAt(greekAlphabet, 17));
	console.log("codePointAt(17): " + Utils.cpAt(greekAlphabet, 17));
	console.log("substr(23, 26): " + Utils.cpSubstr(greekAlphabet, 23, 3));
	console.log("prefix(6): " + Utils.cpSubstr(greekAlphabet, 0, 6));
	console.log("right_tail(6): " + Utils.cpSubstr(greekAlphabet, 6));
	console.log("suffix(6): " + Utils.cpSubstr(greekAlphabet, Utils.cpLength(greekAlphabet) - 6));
	console.log("find(\'δεζ\'): " + Utils.cpIndexOf(greekAlphabet, "δεζ"));
	console.log("find(\'δεζ\') is not found: " + (Utils.cpIndexOf(greekAlphabet, "δεζ") === -1));
	console.log("find(\'bug\'): " + Utils.cpIndexOf(greekAlphabet, "bug"));
	console.log("find(\'bug\') is not found: " + (Utils.cpIndexOf(greekAlphabet, "bug") === -1));
	console.log("rfind(\'αβγ\'): " + Utils.cpLastIndexOf(greekAlphabet, "αβγ"));
	console.log("rfind(\'αβγ\') is not found: " + (Utils.cpLastIndexOf(greekAlphabet, "αβγ") === -1));
	console.log("rfind(\'bug\'): " + Utils.cpLastIndexOf(greekAlphabet, "bug"));
	console.log("rfind(\'bug\') is not found: " + (Utils.cpLastIndexOf(greekAlphabet, "bug") === -1));

/******************************************************************************
 * Because strings are represented using UTF-16 it takes two characters to
 * represent one codepoint for these emoji.  So lengths and positions are twice
 * what we normally would expect when dealing with Unicode characters.  So the
 * standard string functions basically only work correctly with chraracters from
 * the BMP.  Use the functions from Utils module to work correctly with all 
 * Unicode characters.
 *****************************************************************************/
	console.log("Length: " + Utils.cpLength(emoji));
	console.log("charAt(16): " + Utils.uniAt(emoji, 16));
	console.log("codePointAt(16): " + Utils.cpAt(emoji, 16));
	console.log("substr(20, 24): " + Utils.cpSubstr(emoji, 20, 4));
	console.log("prefix(6): " + Utils.cpSubstr(emoji, 0, 6));
	console.log("right_tail(6): " + Utils.cpSubstr(emoji, 6));
	console.log("suffix(6): " + Utils.cpSubstr(emoji, Utils.cpLength(emoji) - 6));
	console.log("find(\'😱😡🤬\'): " + Utils.cpIndexOf(emoji, "😱😡🤬"));
	console.log("find(\'😱😡🤬\') is not found: " + (Utils.cpIndexOf(emoji, "😱😡🤬") === -1));
	console.log("find(\'bug\'): " + Utils.cpIndexOf(emoji, "bug"));
	console.log("find(\'bug\') is not found: " + (Utils.cpIndexOf(emoji, "bug") === -1));
	console.log("rfind(\'😃😇🥰\'): " + Utils.cpLastIndexOf(emoji, "😃😇🥰"));
	console.log("rfind(\'😃😇🥰\') is not found: " + (Utils.cpLastIndexOf(emoji, "😃😇🥰") === -1));
	console.log("rfind(\'bug\'): " + Utils.cpLastIndexOf(emoji, "bug"));
	console.log("rfind(\'bug\') is not found: " + (Utils.cpLastIndexOf(emoji, "bug") === -1));
}
main().catch( e => { console.error(e) } );