class Registry

# File lib/xregistry.rb, line 24
def initialize(app_key = '', vendor_key = '')
  @app_key    = app_key
  @vendor_key = vendor_key
  @on_windows = RUBY_PLATFORM =~ /w(in)?32/

  if @on_windows
    require 'win32/registry'
    @root_key = ['SOFTWARE', vendor_key, app_key].join('\\')
  else
    require 'sqlite3'

    # create registry directory if necessary
    regdir = ENV['HOME'] + '/.registry'
    File.directory?(regdir) || Dir.mkdir(regdir)
    regdir += '/' + vendor_key
    File.directory?(regdir) || Dir.mkdir(regdir)

    @db = SQLite3::Database.new("#{regdir}/#{app_key}.db3")
  end
end

# File lib/xregistry.rb, line 46
def appKey
  @app_key
end

# File lib/xregistry.rb, line 58
def deleteEntry(section, key)
  if @on_windows
    begin
      pkey = [@root_key, section].join('\\')
      access = Win32::Registry::KEY_ALL_ACCESS
      Win32::Registry::HKEY_CURRENT_USER.open(pkey, access) do |reg|
        reg.delete_value(key)
      end
    rescue Win32::Registry::Error
    end
  else
    begin
      @db.execute %Q[delete from "#{section}" where key=?], key
    rescue SQLite3::SQLException
    end
  end
end

# File lib/xregistry.rb, line 78
def deleteSection(section)
  if @on_windows
    begin
      access = Win32::Registry::KEY_ALL_ACCESS
      Win32::Registry::HKEY_CURRENT_USER.open(@root_key, access) do |reg|
        reg.delete_key(section, true)
      end
    rescue Win32::Registry::Error
    end
  else
    @db.execute "drop table if exists \"#{section}\""
  end
end

# File lib/xregistry.rb, line 94
  def each_key
    if @on_windows
      Win32::Registry::HKEY_CURRENT_USER.open(@root_key) do |reg|
        reg.each_key { |subkey, wtime| yield subkey }
      end
    else
      @db.execute <<-EOS do |name|
          select name from sqlite_master where type='table' order by name
          EOS
        yield name[0]
      end
    end
  end

# File lib/xregistry.rb, line 112
def find(section)
  hash = {}
  if @on_windows
    pkey = [@root_key, section].join('\\')
    Win32::Registry::HKEY_CURRENT_USER.open(pkey) do |reg|
      reg.each do |subkey, type, value|
        hash[subkey] = value
      end
    end
  else
    @db.execute %Q[select key, value from "#{section}" order by key] do |row|
      hash[row[0]] = row[1]
    end
  end
  class << hash
    def find(key)
      self[key]
    end
  end
  hash
end

# File lib/xregistry.rb, line 137
def readBoolEntry(section, key, default = false)
  value = readEntry(section, key, default)
  raise TypeError if value.class == Float || value.class == String
  value && value != 0
end

# File lib/xregistry.rb, line 146
def readIntEntry(section, key, default = 0)
  readEntry(section, key, default).to_i
end

# File lib/xregistry.rb, line 153
def readRealEntry(section, key, default = 0.0)
  readEntry(section, key, default).to_f
end

# File lib/xregistry.rb, line 160
def readStringEntry(section, key, default = '')
  readEntry(section, key, default).to_s
end

# File lib/xregistry.rb, line 52
def vendorKey
  @vendor_key
end

# File lib/xregistry.rb, line 166
def writeBoolEntry(section, key, value)
  writeEntry(section, key, value ? 1 : 0)
end

# File lib/xregistry.rb, line 172
def writeIntEntry(section, key, value)
  writeEntry(section, key, value.to_i)
end

# File lib/xregistry.rb, line 179
def writeRealEntry(section, key, value)
  writeEntry(section, key, value.to_f)
end

# File lib/xregistry.rb, line 185
def writeStringEntry(section, key, value)
  writeEntry(section, key, value.to_s)
end

# File lib/xregistry.rb, line 196
def readEntry(section, key, default)
  if @on_windows
    pkey = [@root_key, section].join('\\')
    reg  = Win32::Registry::HKEY_CURRENT_USER.open(pkey)
    reg.read(key)[1]
  else
    @db.get_first_value("select value from \"#{section}\" where key=?",
                        key) || default
  end
rescue
  default
end

# File lib/xregistry.rb, line 210
def writeEntry(section, key, value)
  if @on_windows
    # store real values as strings under Windows
    value = value.to_s if value.class == Float
    begin
      pkey = [@root_key, section].join('\\')
      access = Win32::Registry::KEY_WRITE
      Win32::Registry::HKEY_CURRENT_USER.open(pkey, access) do |reg|
        reg[key] = value
      end
    rescue
      Win32::Registry::HKEY_CURRENT_USER.create(pkey, access) do |reg|
        reg[key] = value
      end
    end
  else
    begin
      @db.execute("update \"#{section}\" set value=? where key=?",
                  [value, key])
      if @db.changes == 0
        # no row was updated so insert a new row
        @db.execute("insert into \"#{section}\"(key, value) values(?,?)",
                    [key, value])
      end
    rescue SQLite3::Exception => e
      if e.to_s =~ /no such table/
        @db.execute "create table \"#{section}\"(key text unique, value)"

        @db.execute("insert into \"#{section}\"(key, value) values(?,?)",
                    [key, value])
      else
        raise e.to_s
      end
    end
  end
end