require 'test/unit'

require 'bit_struct/struct_base'

include BitStruct



class TestTextStruct < Test::Unit::TestCase

  class AlignedText < StructBase
    unsigned :before,  8
    text     :aligned, 32
    unsigned :after,   8
  end

  def test_aligned_text
    data = [ 0x12, ?t, ?s, ?e, ?t, 0x34 ].pack( 'C*' )
    struct = AlignedText.new data
    assert_equal 0x34, struct.before
    assert_equal 'test', struct.aligned
    assert_equal 0x12, struct.after

    struct.before = ?A
    struct.aligned = 'goal'
    struct.after = ?B
    assert_equal ?A, struct.before
    assert_equal 'goal', struct.aligned
    assert_equal ?B, struct.after

    assert_equal 'BlaogA', struct.data
  end

  class UnalignedText < StructBase
    unsigned :before,    4
    text     :unaligned, 24
    unsigned :after,     4
  end

  def test_unaligned_text
    a_hi, a_lo = get_hi_lo ?a
    b_hi, b_lo = get_hi_lo ?b
    c_hi, c_lo = get_hi_lo ?c

    data = [ 12 << 4 | c_hi, c_lo << 4 | b_hi, b_lo << 4 | a_hi, a_lo << 4 | 3 ].pack( 'C*' )

    struct = UnalignedText.new data
    assert_equal 3, struct.before
    assert_equal 'abc', struct.unaligned
    assert_equal 12, struct.after
  end

  def get_hi_lo( char )
    return char >> 4, char & 0x0F
  end

end