// minio.js
// Copyright (C) 2021 Digital Telepresence, LLC
// License: Apache-2.0

'use strict';

const path = require('path');

const mongoose = require('mongoose');
const pug = require('pug');

const Link = mongoose.model('Link');

const striptags = require('striptags');
const isUrlValid = require('url-validation');

const { SiteService, SiteError } = require('../../lib/site-lib');

class LinkService extends SiteService {

  constructor (dtp) {
    super(dtp, module.exports);

    this.populateLink = [
      {
        path: 'user',
        select: '_id username username_lc displayName picture',
      },
    ];
  }

  async start ( ) {
    this.templates = { };

    let script = path.join(this.dtp.config.root, 'app', 'views', 'link', 'components', 'list-item-standalone.pug');
    this.templates.link = pug.compileFile(script);
  }

  renderTemplate (templateId, viewModel) {
    return this.templates[templateId](viewModel);
  }

  async create (user, linkDefinition) {
    if (!user.permissions.canCreateLinks) {
      throw new SiteError(403, 'You are prohibited from creating links');
    }
    this.validateUrl(linkDefinition.href);

    const NOW = new Date();
    const link = new Link();

    link.created = NOW;
    link.user = user._id;
    link.label = striptags(linkDefinition.label.trim());
    link.href = striptags(linkDefinition.href.trim());

    await link.save();
    return link.toObject();
  }

  async update (link, linkDefinition) {
    this.validateUrl(linkDefinition.href);

    const updateOp = { $set: { } };

    if (linkDefinition.label) {
      link.label = updateOp.$set.label = striptags(linkDefinition.label.trim());
    }
    if (linkDefinition.href) {
      link.href = updateOp.$set.href = striptags(linkDefinition.href.trim());
    }

    await Link.updateOne({ _id: link._id }, updateOp);
  }

  async getById (linkId) {
    const link = await Link
      .findById(linkId)
      .populate(this.populateLink)
      .lean();
    return link;
  }

  async getForUser (user, pagination) {
    let links;
    if (pagination) {
      links = await Link
        .find({ user: user._id })
        .sort({ order: 1 })
        .skip(pagination.skip)
        .limit(pagination.cpp)
        .lean();
    } else {
      links = await Link
        .find({ user: user._id })
        .sort({ order: 1 })
        .lean();
    }
    return links;
  }

  async getRecent (maxCount = 3) {
    const links = await Link
      .find()
      .sort({ created: -1 })
      .limit(maxCount)
      .populate(this.populateLink)
      .lean();
    return links;
  }

  async getPopular (maxCount) {
    const links = await Link
      .find()
      .sort({ 'stats.uniqueVisitCount': -1 })
      .limit(maxCount)
      .populate(this.populateLink)
      .lean();
    return links;
  }

  async getAdmin (pagination) {
    const links = await Link
      .find()
      .sort({ created: -1 })
      .skip(pagination.skip)
      .limit(pagination.cpp)
      .populate([
        {
          path: 'user',
          select: '_id username username_lc displayName picture',
        },
      ])
      .lean();
    return links;
  }

  async getTotalCount ( ) {
    return await Link.estimatedDocumentCount();
  }

  async remove (link) {
    const { resource: resourceService } = this.dtp.services;
    await resourceService.remove('Link', link._id);
  }

  async setItemOrder (links) {
    for await (const link of links) {
      this.log.debug('set link order', { link });
      await Link.updateOne({ _id: link._id }, { $set: { order: link.order } });
    }
  }

  validateUrl (href) {
    if (!isUrlValid(href)) {
      throw new SiteError(406, 'Invalid link URL');
    }
    
    const urlTest = href.toLowerCase().trim();
    this.log.debug('testing URL for validity', { urlTest });

    if (!urlTest.startsWith('https://') && !urlTest.startsWith('http://')) {
      throw new SiteError(406, 'Invalid link URL');
    }

    if (urlTest.startsWith('https://libertylinks') || urlTest.startsWith('http://libertylinks') ||
        urlTest.startsWith('https://www.libertylinks') || urlTest.startsWith('http://libertylinks')) {
      throw new SiteError(406, 'Invalid link URL');
    }
  }
}

module.exports = {
  slug: 'link',
  name: 'link',
  create: (dtp) => { return new LinkService(dtp); },
};