"use strict";

const misc = require("./util/misc.js");
const TagCategoryList = require("./models/tag_category_list.js");
const Tag = require("./models/tag.js");

let _stylesheet = null;

function refreshCategoryColorMap() {
    return TagCategoryList.get().then((response) => {
        if (_stylesheet) {
            document.head.removeChild(_stylesheet);
        }
        _stylesheet = document.createElement("style");
        document.head.appendChild(_stylesheet);
        for (let category of response.results) {
            const ruleName = misc.makeCssName(category.name, "tag");
            _stylesheet.sheet.insertRule(
                `.${ruleName} { color: ${category.color}; border-color: ${category.color} }`,
                _stylesheet.sheet.cssRules.length
            );
            _stylesheet.sheet.insertRule(
                `.${ruleName}.selected { color: white; background-color: ${category.color} }`,
                _stylesheet.sheet.cssRules.length
            );
        }
    });
}

function parseTagAndCategory(text) {
    let nameAndCat = text.split(":");
    if (nameAndCat.length > 1) {
        // "cat:my:tag" should parse to category "cat" and tag "my:tag"
        let category = nameAndCat.shift();
        let name = nameAndCat.join(":");
        return {name: name, category: category};
    } else {
        return {name: text, category: null};
    }
}

function resolveTagAndCategory(text) {
    let tagData = parseTagAndCategory(text);
    return _createTagByCategoryAndName(tagData.category, tagData.name);
}

function _createTagByCategoryAndName(category, name) {
    category = category ? category.trim() : "default";
    name = name.trim();
    if (!name) {
        return Promise.reject(new Error("Empty tag name"));
    }
    // if tag with this name already exists, existing category will be used
    return Tag.get(name).then((tag) => {
        return Promise.resolve(tag);
    }, () => {
        const tag = new Tag();
        tag.names = [name];
        tag.category = category;
        return tag.save().then(() => Promise.resolve(tag));
    });
}

module.exports = {
    refreshCategoryColorMap: refreshCategoryColorMap,
    parseTagAndCategory:     parseTagAndCategory,
    resolveTagAndCategory:   resolveTagAndCategory,
};