vlv-search/lib/search.rb

require 'sequel'

def search(params)
  query = params[:q].strip
  offset = (params[:page] - 1) * 10
  username = params[:username].strip
  case params[:type]
  when 'threads'
    sort =
      case params[:sort]
      when 'thread'
        'created_at DESC'
      when 'post'
        'last_post_created_at DESC'
      else
        'created_at DESC'
      end
    search_threads(query, username, sort, offset)
  when 'posts'
    search_posts(query, username, offset)
  else
    Array.new
  end
end

def search_threads(query, username, sort, offset)
  DB[<<-SQL, query, username, username, offset]
    SELECT
      threads.*
    FROM threads
    WHERE
      to_tsvector(title) @@ plainto_tsquery(?)
      AND (LOWER(threads.creator) = LOWER(?) OR ? = '')
    ORDER BY #{sort}
    LIMIT 50
    OFFSET ?;
  SQL
end

def search_posts(query, username, offset)
  DB[<<-SQL, query, username, username, offset]
    SELECT
      posts.*,
      threads.title as thread_title,
      threads.remote_id as remote_thread_id
    FROM posts
    INNER JOIN threads on posts.thread_id = threads.id
    WHERE
      tsv @@ plainto_tsquery(?)
      AND (
        (LOWER(posts.creator) = LOWER(?)) OR (? = '')
      )
    ORDER BY created_at DESC
    LIMIT 50
    OFFSET ?;
  SQL
end