'use strict';

const { timezone, toDate, isExcludedFile, isMatch } = require('./common');
const Promise = require('bluebird');
const { parse: yfm } = require('hexo-front-matter');
const { extname, relative } = require('path');
const { Pattern } = require('hexo-util');

module.exports = ctx => {
  function processPage(file) {
    const Page = ctx.model('Page');
    const { path } = file;
    const doc = Page.findOne({source: path});
    const { config } = ctx;
    const { timezone: timezoneCfg } = config;
    // Deprecated: use_date_for_updated will be removed in future
    const updated_option = config.use_date_for_updated === true ? 'date' : config.updated_option;

    if (file.type === 'skip' && doc) {
      return;
    }

    if (file.type === 'delete') {
      if (doc) {
        return doc.remove();
      }

      return;
    }

    return Promise.all([
      file.stat(),
      file.read()
    ]).spread((stats, content) => {
      const data = yfm(content);
      const output = ctx.render.getOutput(path);

      data.source = path;
      data.raw = content;

      data.date = toDate(data.date);

      if (data.date) {
        if (timezoneCfg) data.date = timezone(data.date, timezoneCfg);
      } else {
        data.date = stats.ctime;
      }

      data.updated = toDate(data.updated);

      if (data.updated) {
        if (timezoneCfg) data.updated = timezone(data.updated, timezoneCfg);
      } else if (updated_option === 'date') {
        data.updated = data.date;
      } else if (updated_option === 'empty') {
        delete data.updated;
      } else {
        data.updated = stats.mtime;
      }

      if (data.permalink) {
        data.path = data.permalink;
        delete data.permalink;

        if (data.path.endsWith('/')) {
          data.path += 'index';
        }

        if (!extname(data.path)) {
          data.path += `.${output}`;
        }
      } else {
        data.path = `${path.substring(0, path.length - extname(path).length)}.${output}`;
      }

      if (!data.layout && output !== 'html' && output !== 'htm') {
        data.layout = false;
      }

      // FIXME: Data may be inserted when reading files. Load it again to prevent
      // race condition. We have to solve this in warehouse.
      const doc = Page.findOne({source: path});

      if (doc) {
        return doc.replace(data);
      }

      return Page.insert(data);
    });
  }

  function processAsset(file) {
    const id = relative(ctx.base_dir, file.source).replace(/\\/g, '/');
    const Asset = ctx.model('Asset');
    const doc = Asset.findById(id);

    if (file.type === 'delete') {
      if (doc) {
        return doc.remove();
      }

      return;
    }

    return Asset.save({
      _id: id,
      path: file.path,
      modified: file.type !== 'skip',
      renderable: file.params.renderable
    });
  }

  return {
    pattern: new Pattern(path => {
      if (isExcludedFile(path, ctx.config)) return;

      return {
        renderable: ctx.render.isRenderable(path) && !isMatch(path, ctx.config.skip_render)
      };
    }),

    process: function assetProcessor(file) {
      if (file.params.renderable) {
        return processPage(file);
      }

      return processAsset(file);
    }
  };
};