Source: fn.js

_import {arr, merge, isEmpty} from '@amekusa/util.js';

/**
 * Returns an object with `key_code` property,
 * which can be passed to {@link Rule#remap} as `from` or `to` properties.
 * @param {string|string[]|array[]} code - key code(s)
 * @param {string|object|string[]} mods - modifiers
 * @param {object} [opts] - optional properties
 * @return {object} an object like: `{ key_code: ... }`
 */
export function key(code, mods = null, opts = null) {
	if (Array.isArray(code)) {
		let r = [];
		for (let i = 0; i < code.length; i++) {
			let I = code[i];
			if (Array.isArray(I)) {
				r.push(key(
					I[0],
					I.length > 1 ? I[1] : mods,
					I.length > 2 ? I[2] : opts
				));
				continue;
			}
			r.push(key(I, mods, opts));
		}
		return r;
	}

	let _mods = {
		mandatory: [],
		optional: []
	};

	function addModifier(mod) {
		mod = mod.trim();
		let m = mod.match(/^\((.+?)\)$/); // is '(optional-key)' ?
		if (m) _mods.optional.push(m[1]);
		else _mods.mandatory.push(mod);
	}

	// parse 'modifier + keycode' expression
	code = (code + '').split('+');
	for (let i = 0; i < code.length - 1; i++) addModifier(code[i]);
	code = code[code.length - 1].trim();

	// parse modifiers
	if (mods) {
		switch (typeof mods) {
		case 'string':
			mods.split('+').forEach(addModifier);
			break;
		case 'object':
			if (Array.isArray(mods)) mods.forEach(addModifier);
			else {
				if (mods.mandatory) _mods.mandatory = _mods.mandatory.concat(arr(mods.mandatory));
				if (mods.optional) _mods.optional = _mods.optional.concat(arr(mods.optional));
			}
		}
	}

	// format & return
	let r = {key_code: code};
	if (!isEmpty(_mods.optional)) r.modifiers = {optional: _mods.optional};
	if (!isEmpty(_mods.mandatory)) {
		if (r.modifiers) r.modifiers.mandatory = _mods.mandatory;
		else r.modifiers = _mods.mandatory;
	}
	return opts ? merge(r, opts, {mergeArrays: true}) : r;
}

/**
 * Returns an object with `pointing_button` property, which can be passed to {@link Rule#remap} as `from` or `to` properties.
 * @param {string} btn - button name
 * - `button1`
 * - `button2`
 * - `button3`
 * - `left` (alias for `button1`)
 * - `right` (alias for `button2`)
 * - `middle` (alias for `button3`)
 * @return {object} an object like: `{ pointing_button: ... }`
 */
export function click(btn) {
	let btns = {
		left: 'button1',
		right: 'button2',
		middle: 'button3'
	};
	return {
		pointing_button: btn in btns ? btns[btn] : btn
	};
}

/**
 * Returns an object with `set_variable` property, which can be passed to {@link Rule#remap} as `to` property.
 * @param {string} name - variable name
 * @param {string|number} value - value to assign
 * @param {object} [opts] - optional properties
 * @return {object} an object like: `{ set_variable: { ... } }`
 */
export function set_var(name, value, opts = null) {
	let r = {
		set_variable: {
			name: name,
			value: value
		}
	};
	return opts ? Object.assign(r, opts) : r;
}

/**
 * Returns an object with `type: 'variable_if'` property, which can be passed to {@link Rule#cond} as a condition.
 * @param {string} name - variable name
 * @param {string|number} value - value to check
 * @return {object} an object like: `{ type: 'variable_if', ... }`
 */
export function if_var(name, value) {
	return {
		type: 'variable_if',
		name: name,
		value: value
	};
}

/**
 * Returns an object with `type: 'variable_unless'` property, which can be passed to {@link Rule#cond} as a condition.
 * @param {string} name - variable name
 * @param {string|number} value - value to check
 * @return {object} an object like: `{ type: 'variable_unless', ... }`
 */
export function unless_var(name, value) {
	return {
		type: 'variable_unless',
		name: name,
		value: value
	};
}

/**
 * Returns an object with `type: 'frontmost_application_if'` property, which can be passed to {@link Rule#cond} as a condition.
 * @param {...string} id - application id
 * @return {object} an object like: `{ type: 'frontmost_application_if', ... }`
 */
export function if_app(...id) {
	return {
		type: 'frontmost_application_if',
		bundle_identifiers: id
	};
}

/**
 * Returns an object with `type: 'frontmost_application_unless'` property, which can be passed to {@link Rule#cond} as a condition.
 * @param {...string} id - application id
 * @return {object} an object like: `{ type: 'frontmost_application_unless', ... }`
 */
export function unless_app(...id) {
	return {
		type: 'frontmost_application_unless',
		bundle_identifiers: id
	};
}

/**
 * Returns an object with `type: 'input_source_if'` property, which can be passed to {@link Rule#cond} as a condition.
 * @param {...string} lang - language code
 * @return {object} an object like: `{ type: 'input_source_if', ... }`
 */
export function if_lang(...lang) {
	return {
		type: 'input_source_if',
		input_sources: lang.map(item => {
			return {language: item};
		})
	};
}

/**
 * Returns an object with `type: 'input_source_unless'` property, which can be passed to {@link Rule#cond} as a condition.
 * @param {...string} lang - language code
 * @return {object} an object like: `{ type: 'input_source_unless', ... }`
 */
export function unless_lang(...lang) {
	return {
		type: 'input_source_unless',
		input_sources: lang.map(item => {
			return {language: item};
		})
	};
}