vlv-search/db/scrape.rb

require 'dotenv/load'
require 'net/http'
require 'nokogiri'
require 'sequel'

require_relative '../lib/auth'

def fetch_page(page_number, cookie)
  url = URI("http://board.vivalavinyl.com/thread/list/#{page_number}")
  http = Net::HTTP.new(url.host, url.port)
  request = Net::HTTP::Get.new(url)
  request['cookie'] = cookie
  response = http.request(request)
  Nokogiri.HTML(response.body)
end

def fetch_thread(thread, cookie)
  url =
    URI(
      "http://board.vivalavinyl.com/thread/view/#{thread[:remote_id]}&ajax=true"
    )
  http = Net::HTTP.new(url.host, url.port)
  request = Net::HTTP::Get.new(url)
  request['cookie'] = cookie
  response = http.request(request)
  Nokogiri.HTML(response.body)
end

def parse_posts(thread, page)
  posts = Array.new

  page.css('.post').each do |_post|
    post = Hash.new
    post[:remote_id] = _post.at_css('ul.view')[:id].split('_')[1].to_i
    post[:creator] = _post.at_css('.memberlink').text.strip
    date, time =
      _post.at_css('.postinfo').text.split('posted this')[1].split('@')
    post[:created_at] = Time.parse("#{date} #{time}")
    post[:body] = _post.at_css('.postbody').children.map(&:to_html).join.strip
    post[:thread_id] = thread[:id]
    posts << post
  end

  posts
end

def insert_post(post, db)
  db.exec(
    'insert into posts (body, timestamp, creator, thread_id, remote_id) values ($1, $2, $3, $4, $5)',
    [
      post[:body],
      post[:created_at].to_s,
      post[:creator],
      post[:thread_id].to_i,
      post[:id].to_i
    ]
  )
end

def parse_threads(page)
  threads = Array.new
  page.css('.even, .odd').each do |row|
    thread = Hash.new
    thread_link = row.at_css('.subject > a')
    next if thread_link.nil?
    thread[:remote_id] = thread_link['href'].split('/')[3]
    thread[:title] = thread_link.text
    creator = row.at_css('.memberlink').text.strip
    creator = creator[0..-2] if creator.match(/\+$/)
    thread[:creator] = creator
    threads << thread
  end
  threads
end

def scrape(first: 0, last: 0)
  cookie = login(ENV['VLV_USERNAME'], ENV['VLV_PASSWORD'])
  db = Sequel.connect(adapter: :postgres, database: ENV['DB_DATABASE'])

  (first..last).each do |page_number|
    page = fetch_page(page_number, cookie)
    threads = parse_threads(page)
    threads.each do |t|
      puts t[:title]

      page = fetch_thread(t, cookie)
      first_post = page.at_css('.postinfo:first-child')

      next if first_post.nil?

      post_info = first_post.text.split('posted this')
      date, time = post_info[1].split('@')
      t[:created_at] = Time.parse("#{date} #{time}")

      thread = db.from(:threads).first(remote_id: t[:remote_id])
      is_new_thread = thread.nil?
      if is_new_thread
        puts '  Inserting thread'
        id =
          db.from(:threads).insert(
            title: t[:title],
            creator: t[:creator],
            remote_id: t[:remote_id],
            created_at: t[:created_at]
          )
        t[:id] = id
        thread = t
      end

      posts = parse_posts(thread, page)

      last_post = posts.last
      unless db.from(:posts).first(remote_id: last_post[:remote_id]).nil?
        puts '  Up to date, skipping'
        next
      end

      posts_count = posts.size
      posts.each_with_index do |p, index|
        msg = "  Inserting post #{index + 1}/#{posts_count}"
        print msg
        if is_new_thread || db.from(:posts).first(remote_id: p[:remote_id]).nil?
          db.from(:posts).insert(
            body: p[:body],
            created_at: p[:created_at],
            thread_id: p[:thread_id],
            creator: p[:creator],
            remote_id: p[:remote_id]
          )
        end
        print "\b" * msg.size unless index == posts_count - 1
      end

      puts
    end
  end
end