const Vue = require('vue');
const VueI18n = require('vue-i18n');
const renderer = require('vue-server-renderer').createRenderer();
const fs = require('fs-extra');
const juice = require('juice');
const smtp = require('./smtp');
const i18n = new VueI18n({
    locale: 'es',
});

Vue.use(VueI18n);

if (!process.env.OPENSSL_CONF)
    process.env.OPENSSL_CONF = '/etc/ssl/';

module.exports = {

    path: `${appPath}/reports`,

    /**
     * Renders a report component
     *
     * @param {String} name - Report name
     * @param {Object} ctx - Request context
     */
    async render(name, ctx) {
        const component = require(`${this.path}/${name}`);
        const prefetchedData = await this.preFetch(component, ctx);

        const app = new Vue({
            i18n,
            render: h => h(component),
        });

        return renderer.renderToString(app).then(renderedHtml => {
            return {
                html: renderedHtml,
                data: prefetchedData,
            };
        });
    },

    /**
     * Prefetch all component data from asyncData method
     *
     * @param {Object} component - Component object
     * @param {Object} ctx - Request context
     */
    async preFetch(component, ctx) {
        const preFetchData = {attachments: []};
        let params = {};
        let data = {};

        if (Object.keys(ctx.body).length > 0)
            params = ctx.body;

        if (Object.keys(ctx.query).length > 0)
            params = ctx.query;

        await this.attachAssets(component);

        if (component.hasOwnProperty('data'))
            data = component.data();

        if (component.hasOwnProperty('asyncData')) {
            const asyncData = await component.asyncData(ctx, params);

            if (asyncData.locale) {
                const locale = component.i18n.messages[asyncData.locale];
                preFetchData.subject = locale.subject;
            }

            if (asyncData.recipient)
                preFetchData.recipient = asyncData.recipient;

            const mergedData = {...data, ...asyncData};
            component.data = function data() {
                return mergedData;
            };
        }

        if (data && data.hasOwnProperty('attachments')) {
            const fileNames = data.attachments;
            fileNames.forEach(attachment => {
                const componentPath = `${this.path}/${component.name}`;
                let fileSrc = componentPath + attachment;

                if (attachment.slice(0, 4) === 'http' || attachment.slice(0, 4) === 'https')
                    fileSrc = attachment;

                const fileName = attachment.split('/').pop();
                preFetchData.attachments.push({
                    filename: fileName,
                    path: fileSrc,
                    cid: attachment,
                });
            });
        }

        if (component.components) {
            const components = component.components;
            const promises = [];

            Object.keys(components).forEach(component => {
                promises.push(this.preFetch(components[component], ctx));
            });

            return Promise.all(promises).then(results => {
                results.forEach(result => {
                    result.attachments.forEach(atth => {
                        preFetchData.attachments.push(atth);
                    });
                });
                return preFetchData;
            });
        }

        return preFetchData;
    },

    async attachAssets(component) {
        const localePath = `${this.path}/${component.name}/locale.js`;
        const templatePath = `${this.path}/${component.name}/index.html`;
        const stylePath = `${this.path}/${component.name}/assets/css/style.css`;

        const template = await fs.readFile(templatePath, 'utf8');
        const css = await fs.readFile(stylePath, 'utf8');

        component.i18n = require(localePath);
        component.template = juice.inlineContent(template, css);
    },

    async toEmail(name, ctx) {
        const rendered = await this.render(name, ctx);
        const data = rendered.data;
        const options = {
            to: data.recipient,
            subject: data.subject,
            html: rendered.html,
            attachments: data.attachments,
        };
        return smtp.send(options);
    },
};