import { ref, unref, triggerRef } from 'vue';

const categories = {};
const loadingModules = {};

function extractCategory(obj, category) {
	return obj.filter(e => e.category == category).reduce((res, elem) => {
		if (!res[elem.phrase])
			res[elem.phrase] = elem.text;
		return res;
	}, {});
}
function reloadRefs(category) {
	while (loadingModules[category].length) {
		var v = loadingModules[category].pop();
		v[0].value = getValueForLoadedPhrase(category, v[1], v[2]);
		triggerRef(v[0]);
		/*unref(v);*/
	}
}
function loadLazy(category, val, phrase, params) {
	// NOTE(chris): load module if it's not loaded yet
	if (loadingModules[category]) {
		loadingModules[category].push([val, phrase, params]);
		if (categories[category]) // NOTE(chris): this is for safety in case the loading finished the moment before the val was pushed into the array
			reloadRefs(category);
		return;
	}
	loadingModules[category] = [[val, phrase, params]];

	axios.get(FHC_JS_DATA_STORAGE_OBJECT.app_root + FHC_JS_DATA_STORAGE_OBJECT.ci_router + '/components/Phrasen/loadModule/' + category).then(res => {
		if (res.data.retval)
			categories[category] = extractCategory(res.data.retval, category);
		else
			categories[category] = {};

		reloadRefs(category);
	}).catch(err => console.error(err));
}
function getValueForLoadedPhrase(category, phrase, params) {
	let result = categories[category][phrase];
	if (!result)
		return '<< PHRASE ' + phrase + '>>';
	if (params)
		result = result.replace(/\{([^}]*)\}/g, (match, p1) => params[p1] === undefined ? match : params[p1]);
	return result;
}


const phrasen = {
	t_ref(category, phrase, params) {
		if (params === undefined && (
			(Array.isArray(category) && category.length == 2) ||
			(category.split && category.split('/').length == 2))
			) {
			params = phrase;
			[category, phrase] = category.split ? category.split('/') : category;
		}
		if (phrase === undefined) {
			console.error('invalid input');
			return '';
		}
		if (!categories[category]) {
			
			var initialval = '';
  			if (window.FHC_JS_PHRASES_STORAGE_OBJECT !== undefined) {
  				var tmp_category = extractCategory(FHC_JS_PHRASES_STORAGE_OBJECT, category);
				if(tmp_category[phrase] !== undefined ) {
					initialval = tmp_category[phrase];
				}
			}
			
			if (!categories[category] || Object.keys(categories[category]).length === 0) {
				categories[category] = undefined;
				let val = ref(initialval);
				loadLazy(category, val, phrase, params);
				return val;
			}
		}
		var result = getValueForLoadedPhrase(category, phrase, params);
		return ref(result);
	},
	t(category, phrase, params) {
		return unref(this.t_ref(category, phrase, params));
	}
};

export default {
	data: () => {
		return {
			p: phrasen
		}
	}
}

// Composable (wrapper for mixin)
export function usePhrasen() {

	function t(category, phrase, params) {
		return phrasen.t(category, phrase, params);
	}

	return {		
		t,
	}

}