require "mysql2"
require File.expand_path(File.dirname(__FILE__) + "/base.rb")
require 'htmlentities'

# Before running this script, paste these lines into your shell,
# then use arrow keys to edit the values
=begin
export DB_HOST="localhost"
export DB_NAME="mylittleforum"
export DB_PW=""
export DB_USER="root"
export TABLE_PREFIX="forum_"
export IMPORT_AFTER="1970-01-01"
export IMAGE_BASE="http://www.example.com/forum"
export BASE="forum"
=end

class ImportScripts::MylittleforumSQL < ImportScripts::Base

  DB_HOST ||= ENV['DB_HOST'] || "localhost"
  DB_NAME ||= ENV['DB_NAME'] || "mylittleforum"
  DB_PW ||= ENV['DB_PW'] || ""
  DB_USER ||= ENV['DB_USER'] || "root"
  TABLE_PREFIX ||= ENV['TABLE_PREFIX'] || "forum_"
  IMPORT_AFTER ||= ENV['IMPORT_AFTER'] || "1970-01-01"
  IMAGE_BASE ||= ENV['IMAGE_BASE'] || ""
  BASE ||= ENV['BASE'] || "forum/"
  BATCH_SIZE = 1000
  CONVERT_HTML = true
  QUIET = nil || ENV['VERBOSE'] == "TRUE"
  FORCE_HOSTNAME = nil || ENV['FORCE_HOSTNAME']

  QUIET = true

  # Site settings
  SiteSetting.disable_emails = "non-staff"
  if FORCE_HOSTNAME
    SiteSetting.force_hostname = FORCE_HOSTNAME
  end

  def initialize

    if IMPORT_AFTER > "1970-01-01"
      print_warning("Importing data after #{IMPORT_AFTER}")
    end

    super
    @htmlentities = HTMLEntities.new
    begin
      @client = Mysql2::Client.new(
        host: DB_HOST,
        username: DB_USER,
        password: DB_PW,
        database: DB_NAME
      )
    rescue Exception => e
      puts '=' * 50
      puts e.message
      puts <<EOM
Cannot log in to database.

Hostname: #{DB_HOST}
Username: #{DB_USER}
Password: #{DB_PW}
database: #{DB_NAME}

You should set these variables:

export DB_HOST="localhost"
export DB_NAME="mylittleforum"
export DB_PW=""
export DB_USER="root"
export TABLE_PREFIX="forum_"
export IMPORT_AFTER="1970-01-01"
export IMAGE_BASE="http://www.example.com/forum"
export BASE="forum"

Exiting.
EOM
      exit
    end
  end

  def execute
    import_users
    import_categories
    import_topics
    import_posts

    update_tl0

    create_permalinks
  end

  def import_users
    puts '', "creating users"

    total_count = mysql_query("SELECT count(*) count FROM #{TABLE_PREFIX}userdata WHERE last_login > '#{IMPORT_AFTER}';").first['count']

    batches(BATCH_SIZE) do |offset|
      results = mysql_query("
             SELECT user_id as UserID, user_name as username,
                user_real_name as Name,
                user_email as Email,
                user_hp as website,
                user_place as Location,
                profile as bio_raw,
                last_login as DateLastActive,
                user_ip as InsertIPAddress,
                user_pw as password,
                logins as days_visited, # user_stats
                registered as DateInserted,
                user_pw as password,
                user_type
             FROM #{TABLE_PREFIX}userdata
		 WHERE last_login > '#{IMPORT_AFTER}'
                 order by UserID ASC
                 LIMIT #{BATCH_SIZE}
                 OFFSET #{offset};")

      break if results.size < 1

      next if all_records_exist? :users, results.map { |u| u['UserID'].to_i }

      create_users(results, total: total_count, offset: offset) do |user|
        next if user['Email'].blank?
        next if @lookup.user_id_from_imported_user_id(user['UserID'])

        # username = fix_username(user['username'])

        { id: user['UserID'],
          email: user['Email'],
          username: user['username'],
          name: user['Name'],
          created_at: user['DateInserted'] == nil ? 0 : Time.zone.at(user['DateInserted']),
          bio_raw: user['bio_raw'],
          registration_ip_address: user['InsertIPAddress'],
          website: user['user_hp'],
          password: user['password'],
          last_seen_at: user['DateLastActive'] == nil ? 0 : Time.zone.at(user['DateLastActive']),
          location: user['Location'],
          admin: user['user_type'] == "admin",
          moderator: user['user_type'] == "mod",
        }
      end
    end
  end

  def fix_username(username)
    olduser = username.dup
    username.gsub!(/Dr\. /, "Dr") # no &
    username.gsub!(/[ +!\/,*()?]/, "_") # can't have these
    username.gsub!(/&/, "_and_") # no &
    username.gsub!(/@/, "_at_") # no @
    username.gsub!(/#/, "_hash_") # no &
    username.gsub!(/\'/, "") # seriously?
    username.gsub!(/[._]+/, "_") # can't have 2 special in a row
    username.gsub!(/_+/, "_") # could result in dupes, but wtf?
    username.gsub!(/_$/, "") # could result in dupes, but wtf?
    if olduser != username
      print_warning ("#{olduser} --> #{username}")
    end
    username
  end

  def import_categories
    puts "", "importing categories..."

    categories = mysql_query("
                              SELECT id as CategoryID,
                              category as Name,
                              description as Description
                              FROM #{TABLE_PREFIX}categories
                              ORDER BY CategoryID ASC
                            ").to_a

    create_categories(categories) do |category|
      {
        id: category['CategoryID'],
        name: CGI.unescapeHTML(category['Name']),
        description: CGI.unescapeHTML(category['Description'])
      }
    end
  end

  def import_topics
    puts "", "importing topics..."

    total_count = mysql_query("SELECT count(*) count FROM #{TABLE_PREFIX}entries
                               WHERE time > '#{IMPORT_AFTER}'
                               AND pid = 0;").first['count']

    batches(BATCH_SIZE) do |offset|
      discussions = mysql_query(
        "SELECT id as DiscussionID,
                category as CategoryID,
                subject as Name,
                text as Body,
                time as DateInserted,
                youtube_link as youtube,
                user_id as InsertUserID
         FROM #{TABLE_PREFIX}entries
         WHERE pid = 0
	 AND time > '#{IMPORT_AFTER}'
         ORDER BY time ASC
         LIMIT #{BATCH_SIZE}
         OFFSET #{offset};")

      break if discussions.size < 1
      next if all_records_exist? :posts, discussions.map { |t| "discussion#" + t['DiscussionID'].to_s }

      create_posts(discussions, total: total_count, offset: offset) do |discussion|

        raw = clean_up(discussion['Body'])

        youtube = nil
        unless discussion['youtube'].blank?
          youtube = clean_youtube(discussion['youtube'])
          raw += "\n#{youtube}\n"
          print_warning(raw)
        end

        {
          id: "discussion#" + discussion['DiscussionID'].to_s,
          user_id: user_id_from_imported_user_id(discussion['InsertUserID']) || Discourse::SYSTEM_USER_ID,
          title: discussion['Name'].gsub('\\"', '"'),
          category: category_id_from_imported_category_id(discussion['CategoryID']),
          raw: raw,
          created_at: Time.zone.at(discussion['DateInserted']),
        }
      end
    end
  end

  def import_posts
    puts "", "importing posts..."

    total_count = mysql_query(
      "SELECT count(*) count
       FROM #{TABLE_PREFIX}entries
       WHERE pid > 0
       AND time > '#{IMPORT_AFTER}';").first['count']

    batches(BATCH_SIZE) do |offset|
      comments = mysql_query(
        "SELECT id as CommentID,
                tid as DiscussionID,
                text as Body,
                time as DateInserted,
                youtube_link as youtube,
                user_id as InsertUserID
         FROM #{TABLE_PREFIX}entries
         WHERE pid > 0
	 AND time > '#{IMPORT_AFTER}'
         ORDER BY time ASC
         LIMIT #{BATCH_SIZE}
         OFFSET #{offset};")

      break if comments.size < 1
      next if all_records_exist? :posts, comments.map { |comment| "comment#" + comment['CommentID'].to_s }

      create_posts(comments, total: total_count, offset: offset) do |comment|
        next unless t = topic_lookup_from_imported_post_id("discussion#" + comment['DiscussionID'].to_s)
        next if comment['Body'].blank?
        raw = clean_up(comment['Body'])
        youtube = nil
        unless comment['youtube'].blank?
          youtube = clean_youtube(comment['youtube'])
          raw += "\n#{youtube}\n"
        end
        {
          id: "comment#" + comment['CommentID'].to_s,
          user_id: user_id_from_imported_user_id(comment['InsertUserID']) || Discourse::SYSTEM_USER_ID,
          topic_id: t[:topic_id],
          raw: clean_up(raw),
          created_at: Time.zone.at(comment['DateInserted'])
        }
      end
    end
  end

  def clean_youtube(youtube_raw)
    youtube_cooked = clean_up(youtube_raw.dup.to_s)
    # get just src from <iframe> and put on a line by itself
    re = /<iframe.+?src="(\S+?)".+?<\/iframe>/mix
    youtube_cooked.gsub!(re) { "\n#{$1}\n" }
    re = /<object.+?src="(\S+?)".+?<\/object>/mix
    youtube_cooked.gsub!(re) { "\n#{$1}\n" }
    youtube_cooked.gsub!(/^\/\//, "https://") # make sure it has a protocol
    unless /http/.match(youtube_cooked) # handle case of only youtube object number
      if youtube_cooked.length < 8 || /[<>=]/.match(youtube_cooked)
        # probably not a youtube id
        youtube_cooked = ""
      else
        youtube_cooked = 'https://www.youtube.com/watch?v=' + youtube_cooked
      end
    end
    print_warning("#{'-' * 40}\nBefore: #{youtube_raw}\nAfter: #{youtube_cooked}") unless QUIET

    youtube_cooked
  end

  def clean_up(raw)
    return "" if raw.blank?

    # decode HTML entities
    raw = @htmlentities.decode(raw)

    # don't \ quotes
    raw = raw.gsub('\\"', '"')
    raw = raw.gsub("\\'", "'")

    raw = raw.gsub(/\[b\]/i, "<strong>")
    raw = raw.gsub(/\[\/b\]/i, "</strong>")

    raw = raw.gsub(/\[i\]/i, "<em>")
    raw = raw.gsub(/\[\/i\]/i, "</em>")

    raw = raw.gsub(/\[u\]/i, "<em>")
    raw = raw.gsub(/\[\/u\]/i, "</em>")

    raw = raw.gsub(/\[url\](\S+)\[\/url\]/im) { "#{$1}" }
    raw = raw.gsub(/\[link\](\S+)\[\/link\]/im) { "#{$1}" }

    # URL & LINK with text
    raw = raw.gsub(/\[url=(\S+?)\](.*?)\[\/url\]/im) { "<a href=\"#{$1}\">#{$2}</a>" }
    raw = raw.gsub(/\[link=(\S+?)\](.*?)\[\/link\]/im) { "<a href=\"#{$1}\">#{$2}</a>" }

    # remote images
    raw = raw.gsub(/\[img\](https?:.+?)\[\/img\]/im) { "<img src=\"#{$1}\">" }
    raw = raw.gsub(/\[img=(https?.+?)\](.+?)\[\/img\]/im) { "<img src=\"#{$1}\" alt=\"#{$2}\">" }
    # local images
    raw = raw.gsub(/\[img\](.+?)\[\/img\]/i) { "<img src=\"#{IMAGE_BASE}/#{$1}\">" }
    raw = raw.gsub(/\[img=(.+?)\](https?.+?)\[\/img\]/im) { "<img src=\"#{IMAGE_BASE}/#{$1}\" alt=\"#{$2}\">" }

    # Convert image bbcode
    raw.gsub!(/\[img=(\d+),(\d+)\]([^\]]*)\[\/img\]/im, '<img width="\1" height="\2" src="\3">')

    # [div]s are really [quote]s
    raw.gsub!(/\[div\]/mix, "[quote]")
    raw.gsub!(/\[\/div\]/mix, "[/quote]")

    # [postedby] -> link to @user
    raw.gsub(/\[postedby\](.+?)\[b\](.+?)\[\/b\]\[\/postedby\]/i) { "#{$1}@#{$2}" }

    # CODE (not tested)
    raw = raw.gsub(/\[code\](\S+)\[\/code\]/im) { "```\n#{$1}\n```" }
    raw = raw.gsub(/\[pre\](\S+)\[\/pre\]/im) { "```\n#{$1}\n```" }

    raw = raw.gsub(/(https:\/\/youtu\S+)/i) { "\n#{$1}\n" } #youtube links on line by themselves

    # no center
    raw = raw.gsub(/\[\/?center\]/i, "")

    # no size
    raw = raw.gsub(/\[\/?size.*?\]/i, "")

    ### FROM VANILLA:

    # fix whitespaces
    raw = raw.gsub(/(\\r)?\\n/, "\n")
      .gsub("\\t", "\t")

    unless CONVERT_HTML
      # replace all chevrons with HTML entities
      # NOTE: must be done
      #  - AFTER all the "code" processing
      #  - BEFORE the "quote" processing
      raw = raw.gsub(/`([^`]+)`/im) { "`" + $1.gsub("<", "\u2603") + "`" }
        .gsub("<", "&lt;")
        .gsub("\u2603", "<")

      raw = raw.gsub(/`([^`]+)`/im) { "`" + $1.gsub(">", "\u2603") + "`" }
        .gsub(">", "&gt;")
        .gsub("\u2603", ">")
    end

    # Remove the color tag
    raw.gsub!(/\[color=[#a-z0-9]+\]/i, "")
    raw.gsub!(/\[\/color\]/i, "")
    ### END VANILLA:

    raw
  end

  def staff_guardian
    @_staff_guardian ||= Guardian.new(Discourse.system_user)
  end

  def mysql_query(sql)
    @client.query(sql)
    # @client.query(sql, cache_rows: false) #segfault: cache_rows: false causes segmentation fault
  end

  def create_permalinks
    puts '', 'Creating redirects...', ''

    puts '', 'Users...', ''
    User.find_each do |u|
      ucf = u.custom_fields
      if ucf && ucf["import_id"] && ucf["import_username"]
        Permalink.create(url: "#{BASE}/user-id-#{ucf['import_id']}.html", external_url: "/u/#{u.username}") rescue nil
        print '.'
      end
    end

    puts '', 'Posts...', ''
    Post.find_each do |post|
      pcf = post.custom_fields
      if pcf && pcf["import_id"]
        topic = post.topic
        id = pcf["import_id"].split('#').last
        if post.post_number == 1
          Permalink.create(url: "#{BASE}/forum_entry-id-#{id}.html", topic_id: topic.id) rescue nil
          unless QUIET
            print_warning("forum_entry-id-#{id}.html --> http://localhost:3000/t/#{topic.id}")
          end
        else
          Permalink.create(url: "#{BASE}/forum_entry-id-#{id}.html", post_id: post.id) rescue nil
          unless QUIET
            print_warning("forum_entry-id-#{id}.html --> http://localhost:3000/t/#{topic.id}/#{post.id}")
          end
        end
        print '.'
      end
    end

    puts '', 'Categories...', ''
    Category.find_each do |cat|
      ccf = cat.custom_fields
      next unless id = ccf["import_id"]
      unless QUIET
        print_warning("forum-category-#{id}.html --> /t/#{cat.id}")
      end
      Permalink.create(url: "#{BASE}/forum-category-#{id}.html", category_id: cat.id) rescue nil
      print '.'
    end
  end

  def print_warning(message)
    $stderr.puts "#{message}"
  end

end

ImportScripts::MylittleforumSQL.new.perform