#!/usr/bin/env ruby
require 'optparse'
require 'pathname'

class Pathname; alias / +; end

class Options
  def initialize(argv)
    @dry_run = false
    @ruremadir = Pathname("~/.rurema").expand_path
    @rubyver = RUBY_VERSION
    @command = nil
    @query = ""

    @optionparser = OptionParser.new{|o|
      o.on("--init",
           "initialize rurema"){
        @command = :init
      }
      o.on("--update",
           "update documents and database"){
        @command = :update
      }

      o.on("--dry-run",
           "show commands only"){
        @dry_run = true 
      }
      o.on("--ruremadir=PATH",
           "specify rurema directory (default: #{@ruremadir})"){|path|
        @ruremadir = Pathname(path)
      }
      o.on("--rubyver=STR",
           "specify Ruby version (default: #{@rubyver})"){|str|
        @rubyver = str
      }
      o.on("--help",
           "show this message"){
        puts o
        exit
      }
    }
    @query = @optionparser.parse(argv).join(" ")
  end
  attr_reader :dry_run, :ruremadir, :rubyver
  attr_reader :command, :query

  def usage
    puts @optionparser
  end
end

class Rurema
  SVN_URL = "http://jp.rubyist.net/svn/rurema" 

  def initialize(opt=Options.new(ARGV))
    @opt = opt
  end

  def run
    if @opt.command
      send(@opt.command)
    elsif @opt.query.empty?
      @opt.usage
    else
      search(@opt.query, @opt.rubyver)
    end
  end

  def init
    sh "svn co -rHEAD #{SVN_URL}/doctree/trunk #{doctree_path}"
    sh "svn co -rHEAD #{SVN_URL}/bitclust/trunk #{bitclust_path}"
    init_db(@opt.rubyver)
  end

  def update
    sh "svn up #{doctree_path}"
    refresh_db(@opt.rubyver)
  end

  def search(query, ver)
    unless has_db?(ver)
      puts "You don't have a database for ruby #{ver}."
      puts "Make it now? [y/n]"
      if $stdin.gets.chomp.downcase == "y"
        init_db(ver)
      else
        exit
      end
    end

    sh "#{bitclust_path/'bin/refe.rb'}" +
          " #{query} -d #{db_path(ver)}", :silent => true
  end

  def server
    # TODO
  end
  
  private

  def init_db(ver)
    sh "#{bitclust_path/'bin/bitclust.rb'}" +
          " -d #{db_path(ver)} init version=#{ver} encoding=euc-jp"

    refresh_db(ver)
  end

  def refresh_db(ver)
    puts "Updating Rurema database:"
    puts "This will take a few minutes. Please be patient."
    sh "#{bitclust_path/'bin/bitclust.rb'}" +
          " -d #{db_path(ver)}" +
          " update --stdlibtree=#{doctree_path/'refm/api/src'}"
  end

  def bitclust_path
    @opt.ruremadir / "bitclust"
  end

  def doctree_path
    @opt.ruremadir / "doctree"
  end

  def has_db?(ver)
    db_path(ver).directory?
  end

  def db_path(ver)
    raise ArgumentError, "malformed ver: #{ver}" unless ver =~ /\A\d.\d.\d\z/
    @opt.ruremadir / "db" / ver
  end

  def sh(cmd, opt={})
    puts cmd unless opt[:silent]
    system cmd unless @opt.dry_run
  end
end

Rurema.new.run