import { CommonUtils } from '@farris/ui-common';
import { Injectable, LOCALE_ID, Inject, InjectionToken, Optional } from '@angular/core';

import { FARRIS_LOCALES } from './locales';

export const FARRIS_LOCAL_CUSTOM_DATA = new InjectionToken('自定义语言数据， 格式：{ "localeCode": { "name": "value" } }');
@Injectable({
    providedIn: 'root'
})
export class LocaleService {

    langData: any;

    constructor(@Inject(LOCALE_ID) public localeId: string, private utils: CommonUtils,
                @Optional() @Inject(FARRIS_LOCAL_CUSTOM_DATA) private localeData: any) {
        if (!localeId) {
            localeId = 'zh-CHS';
        }

        // 合并语言资源
        this.setLocaleData(localeData);
    }

    /** 获取语言资源
     *  path : 资源路径，如:
     *  ```
     *  getResources('zh-CHS') // 返回所有中文语言资源
     *  getResources('zh-CHS.lookup') // 返回所有中文下帮助的资源
     *  ```
     */
    getResources( path = '') {
        if (path) {
            return this.utils.getValue(path, FARRIS_LOCALES);
        }
        return FARRIS_LOCALES;
    }

    getComponentOptions(ctrlName) {
        return this.langData[ctrlName];
    }

    getValue(propertyName: string) {
        const val = this.utils.getValue(propertyName, this.langData);
        if (val) {
            return val;
        } else {
            console.warn(`Can\'t find language Data for the ${propertyName}`);
        }
    }

    /** 合并现有的多语资源 */
    setLocaleData(localeData = null) {
        if (localeData) {
            // 解析得到提供的语言编码
            const langCodes = Object.keys(localeData);
            langCodes.forEach((code: string) => {
                const resName = Object.keys(localeData[code]);
                resName.forEach(k => {
                    this.appendLanguageResource(k, localeData[code][k], code);
                });
            });
        }

        this.langData = FARRIS_LOCALES[this.localeId];
        if (!this.langData) {
            this.langData = FARRIS_LOCALES['zh-CHS'];
        }
    }

    private appendLanguageResource(key: string, data: any, lang: string = this.localeId) {
        if (!lang) {
            this.langData[key] = this.langData[key] || {};
            this.langData[key] = Object.assign(this.langData[key], data || {});
        } else {
            FARRIS_LOCALES[lang][key] = data || {};
        }
    }
}