package azblob

import (
	"bytes"

	chk "gopkg.in/check.v1"
)

func (s *aztestsSuite) TestBytesWriterWriteAt(c *chk.C) {
	b := make([]byte, 10)
	buffer := newBytesWriter(b)

	count, err := buffer.WriteAt([]byte{1, 2}, 10)
	c.Assert(err, chk.ErrorMatches, "Offset value is out of range")
	c.Assert(count, chk.Equals, 0)

	count, err = buffer.WriteAt([]byte{1, 2}, -1)
	c.Assert(err, chk.ErrorMatches, "Offset value is out of range")
	c.Assert(count, chk.Equals, 0)

	count, err = buffer.WriteAt([]byte{1, 2}, 9)
	c.Assert(err, chk.ErrorMatches, "Not enough space for all bytes")
	c.Assert(count, chk.Equals, 1)
	c.Assert(bytes.Compare(b, []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 1}), chk.Equals, 0)

	count, err = buffer.WriteAt([]byte{1, 2}, 8)
	c.Assert(err, chk.IsNil)
	c.Assert(count, chk.Equals, 2)
	c.Assert(bytes.Compare(b, []byte{0, 0, 0, 0, 0, 0, 0, 0, 1, 2}), chk.Equals, 0)
}