/**
 * 模板字符串解析，如：template = 'hahaha{name}_{id}' ,param = {name: 'hh', id: 1}
 * 解析后为 hahahahh_1
 * @param template 模板字符串
 * @param param   参数占位符
 * @returns
 */
export function templateResolve(template: string, param: any) {
	return template.replace(/\{\w+\}/g, (word) => {
		const key = word.substring(1, word.length - 1);
		const value = param[key];
		if (value != null || value != undefined) {
			return value;
		}
		return '';
	});
}

// 首字符头像
export function letterAvatar(name: string, size = 60, color = '') {
	name = name || '';
	size = size || 60;
	var colours = [
			'#1abc9c',
			'#2ecc71',
			'#3498db',
			'#9b59b6',
			'#34495e',
			'#16a085',
			'#27ae60',
			'#2980b9',
			'#8e44ad',
			'#2c3e50',
			'#f1c40f',
			'#e67e22',
			'#e74c3c',
			'#00bcd4',
			'#95a5a6',
			'#f39c12',
			'#d35400',
			'#c0392b',
			'#bdc3c7',
			'#7f8c8d',
		],
		nameSplit = String(name).split(' '),
		initials,
		charIndex,
		colourIndex,
		canvas,
		context,
		dataURI;

	if (nameSplit.length == 1) {
		initials = nameSplit[0] ? nameSplit[0].charAt(0) : '?';
	} else {
		initials = nameSplit[0].charAt(0) + nameSplit[1].charAt(0);
	}
	if (window.devicePixelRatio) {
		size = size * window.devicePixelRatio;
	}
	initials = initials.toLocaleUpperCase();
	charIndex = (initials == '?' ? 72 : initials.charCodeAt(0)) - 64;
	colourIndex = charIndex % 20;
	canvas = document.createElement('canvas');
	canvas.width = size;
	canvas.height = size;
	context = canvas.getContext('2d') as any;

	context.fillStyle = color ? color : colours[colourIndex - 1];
	context.fillRect(0, 0, canvas.width, canvas.height);
	context.font = Math.round(canvas.width / 2) + "px 'Microsoft Yahei'";
	context.textAlign = 'center';
	context.fillStyle = '#FFF';
	context.fillText(initials, size / 2, size / 1.5);
	dataURI = canvas.toDataURL();
	canvas = null;
	return dataURI;
}
