package packp

import (
	"bytes"
	"io"

	"gopkg.in/src-d/go-git.v4/plumbing"
	"gopkg.in/src-d/go-git.v4/plumbing/format/pktline"

	. "gopkg.in/check.v1"
)

type UpdReqDecodeSuite struct{}

var _ = Suite(&UpdReqDecodeSuite{})

func (s *UpdReqDecodeSuite) TestEmpty(c *C) {
	r := NewReferenceUpdateRequest()
	var buf bytes.Buffer
	c.Assert(r.Decode(&buf), Equals, ErrEmpty)
	c.Assert(r, DeepEquals, NewReferenceUpdateRequest())
}

func (s *UpdReqDecodeSuite) TestInvalidPktlines(c *C) {
	r := NewReferenceUpdateRequest()
	input := bytes.NewReader([]byte("xxxxxxxxxx"))
	c.Assert(r.Decode(input), ErrorMatches, "invalid pkt-len found")
}

func (s *UpdReqDecodeSuite) TestInvalidShadow(c *C) {
	payloads := []string{
		"shallow",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid shallow line length: expected 48, got 7$")

	payloads = []string{
		"shallow ",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid shallow line length: expected 48, got 8$")

	payloads = []string{
		"shallow 1ecf0ef2c2dffb796033e5a02219af86ec65",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid shallow line length: expected 48, got 44$")

	payloads = []string{
		"shallow 1ecf0ef2c2dffb796033e5a02219af86ec6584e54",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid shallow line length: expected 48, got 49$")

	payloads = []string{
		"shallow 1ecf0ef2c2dffb796033e5a02219af86ec6584eu",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid shallow object id: invalid hash: .*")
}

func (s *UpdReqDecodeSuite) TestMalformedCommand(c *C) {
	payloads := []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5x2ecf0ef2c2dffb796033e5a02219af86ec6584e5xmyref\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: malformed command: EOF$")

	payloads = []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref\x00",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5x2ecf0ef2c2dffb796033e5a02219af86ec6584e5xmyref",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: malformed command: EOF$")
}

func (s *UpdReqDecodeSuite) TestInvalidCommandInvalidHash(c *C) {
	payloads := []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid old object id: invalid hash size: expected 40, got 39$")

	payloads = []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e myref\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid new object id: invalid hash size: expected 40, got 39$")

	payloads = []string{
		"1ecf0ef2c2dffb796033e5a02219af86e 2ecf0ef2c2dffb796033e5a02219af86ec6 m\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid command and capabilities line length: expected at least 84, got 72$")

	payloads = []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584eu 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid old object id: invalid hash: .*$")

	payloads = []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584eu myref\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid new object id: invalid hash: .*$")
}

func (s *UpdReqDecodeSuite) TestInvalidCommandMissingNullDelimiter(c *C) {
	payloads := []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "capabilities delimiter not found")
}

func (s *UpdReqDecodeSuite) TestInvalidCommandMissingName(c *C) {
	payloads := []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5\x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid command and capabilities line length: expected at least 84, got 82$")

	payloads = []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 \x00",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid command and capabilities line length: expected at least 84, got 83$")

	payloads = []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref\x00",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid command line length: expected at least 83, got 81$")

	payloads = []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref\x00",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 ",
		pktline.FlushString,
	}
	s.testDecoderErrorMatches(c, toPktLines(c, payloads), "^malformed request: invalid command line length: expected at least 83, got 82$")
}

func (s *UpdReqDecodeSuite) TestOneUpdateCommand(c *C) {
	hash1 := plumbing.NewHash("1ecf0ef2c2dffb796033e5a02219af86ec6584e5")
	hash2 := plumbing.NewHash("2ecf0ef2c2dffb796033e5a02219af86ec6584e5")
	name := "myref"

	expected := NewReferenceUpdateRequest()
	expected.Commands = []*Command{
		{Name: name, Old: hash1, New: hash2},
	}

	payloads := []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref\x00",
		pktline.FlushString,
	}

	c.Assert(s.testDecodeOK(c, payloads), DeepEquals, expected)
}

func (s *UpdReqDecodeSuite) TestMultipleCommands(c *C) {
	hash1 := plumbing.NewHash("1ecf0ef2c2dffb796033e5a02219af86ec6584e5")
	hash2 := plumbing.NewHash("2ecf0ef2c2dffb796033e5a02219af86ec6584e5")

	expected := NewReferenceUpdateRequest()
	expected.Commands = []*Command{
		{Name: "myref1", Old: hash1, New: hash2},
		{Name: "myref2", Old: plumbing.ZeroHash, New: hash2},
		{Name: "myref3", Old: hash1, New: plumbing.ZeroHash},
	}

	payloads := []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref1\x00",
		"0000000000000000000000000000000000000000 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref2",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 0000000000000000000000000000000000000000 myref3",
		pktline.FlushString,
	}

	c.Assert(s.testDecodeOK(c, payloads).Commands, DeepEquals, expected.Commands)
	c.Assert(s.testDecodeOK(c, payloads).Shallow, DeepEquals, expected.Shallow)
	c.Assert(s.testDecodeOK(c, payloads).Capabilities, DeepEquals, expected.Capabilities)
	c.Assert(s.testDecodeOK(c, payloads), DeepEquals, expected)
}

func (s *UpdReqDecodeSuite) TestMultipleCommandsAndCapabilities(c *C) {
	hash1 := plumbing.NewHash("1ecf0ef2c2dffb796033e5a02219af86ec6584e5")
	hash2 := plumbing.NewHash("2ecf0ef2c2dffb796033e5a02219af86ec6584e5")

	expected := NewReferenceUpdateRequest()
	expected.Commands = []*Command{
		{Name: "myref1", Old: hash1, New: hash2},
		{Name: "myref2", Old: plumbing.ZeroHash, New: hash2},
		{Name: "myref3", Old: hash1, New: plumbing.ZeroHash},
	}
	expected.Capabilities.Add("shallow")

	payloads := []string{
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref1\x00shallow",
		"0000000000000000000000000000000000000000 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref2",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 0000000000000000000000000000000000000000 myref3",
		pktline.FlushString,
	}

	c.Assert(s.testDecodeOK(c, payloads), DeepEquals, expected)
}

func (s *UpdReqDecodeSuite) TestMultipleCommandsAndCapabilitiesShallow(c *C) {
	hash1 := plumbing.NewHash("1ecf0ef2c2dffb796033e5a02219af86ec6584e5")
	hash2 := plumbing.NewHash("2ecf0ef2c2dffb796033e5a02219af86ec6584e5")

	expected := NewReferenceUpdateRequest()
	expected.Commands = []*Command{
		{Name: "myref1", Old: hash1, New: hash2},
		{Name: "myref2", Old: plumbing.ZeroHash, New: hash2},
		{Name: "myref3", Old: hash1, New: plumbing.ZeroHash},
	}
	expected.Capabilities.Add("shallow")
	expected.Shallow = &hash1

	payloads := []string{
		"shallow 1ecf0ef2c2dffb796033e5a02219af86ec6584e5",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref1\x00shallow",
		"0000000000000000000000000000000000000000 2ecf0ef2c2dffb796033e5a02219af86ec6584e5 myref2",
		"1ecf0ef2c2dffb796033e5a02219af86ec6584e5 0000000000000000000000000000000000000000 myref3",
		pktline.FlushString,
	}

	c.Assert(s.testDecodeOK(c, payloads), DeepEquals, expected)
}

func (s *UpdReqDecodeSuite) testDecoderErrorMatches(c *C, input io.Reader, pattern string) {
	r := NewReferenceUpdateRequest()
	c.Assert(r.Decode(input), ErrorMatches, pattern)
}

func (s *UpdReqDecodeSuite) testDecodeOK(c *C, payloads []string) *ReferenceUpdateRequest {
	var buf bytes.Buffer
	e := pktline.NewEncoder(&buf)
	err := e.EncodeString(payloads...)
	c.Assert(err, IsNil)

	r := NewReferenceUpdateRequest()
	c.Assert(r.Decode(&buf), IsNil)

	return r
}