// Copyright (c) 2014-2016 The btcsuite developers
// Copyright (c) 2015-2021 The Decred developers
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.

package wire

import (
	"bytes"
	"errors"
	"io"
	"reflect"
	"testing"

	"github.com/davecgh/go-spew/spew"
)

// TestRejectCodeStringer tests the stringized output for the reject code type.
func TestRejectCodeStringer(t *testing.T) {
	tests := []struct {
		in   RejectCode
		want string
	}{
		{RejectMalformed, "REJECT_MALFORMED"},
		{RejectInvalid, "REJECT_INVALID"},
		{RejectObsolete, "REJECT_OBSOLETE"},
		{RejectDuplicate, "REJECT_DUPLICATE"},
		{RejectNonstandard, "REJECT_NONSTANDARD"},
		{RejectDust, "REJECT_DUST"},
		{RejectInsufficientFee, "REJECT_INSUFFICIENTFEE"},
		{RejectCheckpoint, "REJECT_CHECKPOINT"},
		{0xff, "Unknown RejectCode (255)"},
	}

	t.Logf("Running %d tests", len(tests))
	for i, test := range tests {
		result := test.in.String()
		if result != test.want {
			t.Errorf("String #%d\n got: %s want: %s", i, result,
				test.want)
			continue
		}
	}
}

// TestRejectLatest tests the MsgReject API against the latest protocol version
// to ensure it is no longer valid.
func TestRejectLatest(t *testing.T) {
	pver := ProtocolVersion

	// Create reject message data.
	rejCommand := (&MsgBlock{}).Command()
	rejCode := RejectDuplicate
	rejReason := "duplicate block"
	rejHash := mainNetGenesisHash

	// Ensure we get the correct data back out.
	msg := NewMsgReject(rejCommand, rejCode, rejReason)
	msg.Hash = rejHash

	// Ensure max payload is expected value.
	wantPayload := uint32(0)
	maxPayload := msg.MaxPayloadLength(pver)
	if maxPayload != wantPayload {
		t.Errorf("MaxPayloadLength: wrong max payload length for protocol "+
			"version %d - got %v, want %v", pver, maxPayload, wantPayload)
	}

	// Ensure encode fails with the latest protocol version.
	var buf bytes.Buffer
	err := msg.BtcEncode(&buf, pver)
	if !errors.Is(err, ErrMsgInvalidForPVer) {
		t.Errorf("MsgReject encode unexpected err -- got %v, want %v", err,
			ErrMsgInvalidForPVer)
	}

	// Ensure decode fails with the latest protocol version.
	var readMsg MsgReject
	err = readMsg.BtcDecode(&buf, pver)
	if !errors.Is(err, ErrMsgInvalidForPVer) {
		t.Errorf("MsgReject decode unexpected err -- got %v, want %v", err,
			ErrMsgInvalidForPVer)
	}
}

// TestRejectLastSupported tests the MsgReject API against the last protocol
// version that was supported.
func TestRejectLastSupported(t *testing.T) {
	pver := RemoveRejectVersion - 1

	// Create reject message data.
	rejCommand := (&MsgBlock{}).Command()
	rejCode := RejectDuplicate
	rejReason := "duplicate block"
	rejHash := mainNetGenesisHash

	// Ensure we get the correct data back out.
	msg := NewMsgReject(rejCommand, rejCode, rejReason)
	msg.Hash = rejHash
	if msg.Cmd != rejCommand {
		t.Errorf("NewMsgReject: wrong rejected command - got %v, "+
			"want %v", msg.Cmd, rejCommand)
	}
	if msg.Code != rejCode {
		t.Errorf("NewMsgReject: wrong rejected code - got %v, "+
			"want %v", msg.Code, rejCode)
	}
	if msg.Reason != rejReason {
		t.Errorf("NewMsgReject: wrong rejected reason - got %v, "+
			"want %v", msg.Reason, rejReason)
	}

	// Ensure the command is expected value.
	wantCmd := "reject"
	if cmd := msg.Command(); cmd != wantCmd {
		t.Errorf("NewMsgReject: wrong command - got %v want %v",
			cmd, wantCmd)
	}

	// Ensure max payload is expected value for the last protocol version that
	// was supported.
	wantPayload := uint32(MaxMessagePayload)
	maxPayload := msg.MaxPayloadLength(pver)
	if maxPayload != wantPayload {
		t.Errorf("MaxPayloadLength: wrong max payload length for "+
			"protocol version %d - got %v, want %v", pver,
			maxPayload, wantPayload)
	}

	// Test encode for the last protocol version that was supported.
	var buf bytes.Buffer
	err := msg.BtcEncode(&buf, pver)
	if err != nil {
		t.Errorf("encode of MsgReject failed %v err <%v>", msg, err)
	}

	// Test decode for the last protocol version that was supported.
	readMsg := MsgReject{}
	err = readMsg.BtcDecode(&buf, pver)
	if err != nil {
		t.Errorf("decode of MsgReject failed %v err <%v>", buf.Bytes(),
			err)
	}

	// Ensure decoded data is the same.
	if msg.Cmd != readMsg.Cmd {
		t.Errorf("Should get same reject command - got %v, want %v",
			readMsg.Cmd, msg.Cmd)
	}
	if msg.Code != readMsg.Code {
		t.Errorf("Should get same reject code - got %v, want %v",
			readMsg.Code, msg.Code)
	}
	if msg.Reason != readMsg.Reason {
		t.Errorf("Should get same reject reason - got %v, want %v",
			readMsg.Reason, msg.Reason)
	}
	if msg.Hash != readMsg.Hash {
		t.Errorf("Should get same reject hash - got %v, want %v",
			readMsg.Hash, msg.Hash)
	}
}

// TestRejectWire tests the MsgReject wire encode and decode for various
// protocol versions.
func TestRejectWire(t *testing.T) {
	tests := []struct {
		msg  MsgReject // Message to encode
		buf  []byte    // Wire encoding
		pver uint32    // Protocol version for wire encoding
	}{
		// Latest protocol version rejected command version (no hash).
		{
			MsgReject{
				Cmd:    "version",
				Code:   RejectDuplicate,
				Reason: "duplicate version",
			},
			[]byte{
				0x07, 0x76, 0x65, 0x72, 0x73, 0x69, 0x6f, 0x6e, // "version"
				0x12, // RejectDuplicate
				0x11, 0x64, 0x75, 0x70, 0x6c, 0x69, 0x63, 0x61,
				0x74, 0x65, 0x20, 0x76, 0x65, 0x72, 0x73, 0x69,
				0x6f, 0x6e, // "duplicate version"
			},
			RemoveRejectVersion - 1,
		},
		// Latest protocol version rejected command block (has hash).
		{
			MsgReject{
				Cmd:    "block",
				Code:   RejectDuplicate,
				Reason: "duplicate block",
				Hash:   mainNetGenesisHash,
			},
			[]byte{
				0x05, 0x62, 0x6c, 0x6f, 0x63, 0x6b, // "block"
				0x12, // RejectDuplicate
				0x0f, 0x64, 0x75, 0x70, 0x6c, 0x69, 0x63, 0x61,
				0x74, 0x65, 0x20, 0x62, 0x6c, 0x6f, 0x63, 0x6b, // "duplicate block"
				0x6f, 0xe2, 0x8c, 0x0a, 0xb6, 0xf1, 0xb3, 0x72,
				0xc1, 0xa6, 0xa2, 0x46, 0xae, 0x63, 0xf7, 0x4f,
				0x93, 0x1e, 0x83, 0x65, 0xe1, 0x5a, 0x08, 0x9c,
				0x68, 0xd6, 0x19, 0x00, 0x00, 0x00, 0x00, 0x00, // mainNetGenesisHash
			},
			RemoveRejectVersion - 1,
		},
	}

	t.Logf("Running %d tests", len(tests))
	for i, test := range tests {
		// Encode the message to wire format.
		var buf bytes.Buffer
		err := test.msg.BtcEncode(&buf, test.pver)
		if err != nil {
			t.Errorf("BtcEncode #%d error %v", i, err)
			continue
		}
		if !bytes.Equal(buf.Bytes(), test.buf) {
			t.Errorf("BtcEncode #%d\n got: %s want: %s", i,
				spew.Sdump(buf.Bytes()), spew.Sdump(test.buf))
			continue
		}

		// Decode the message from wire format.
		var msg MsgReject
		rbuf := bytes.NewReader(test.buf)
		err = msg.BtcDecode(rbuf, test.pver)
		if err != nil {
			t.Errorf("BtcDecode #%d error %v", i, err)
			continue
		}
		if !reflect.DeepEqual(msg, test.msg) {
			t.Errorf("BtcDecode #%d\n got: %s want: %s", i,
				spew.Sdump(msg), spew.Sdump(test.msg))
			continue
		}
	}
}

// TestRejectWireErrors performs negative tests against wire encode and decode
// of MsgReject as of the last protocol version it was supported to confirm
// error paths work correctly.
func TestRejectWireErrors(t *testing.T) {
	pver := RemoveRejectVersion - 1

	baseReject := NewMsgReject("block", RejectDuplicate, "duplicate block")
	baseReject.Hash = mainNetGenesisHash
	baseRejectEncoded := []byte{
		0x05, 0x62, 0x6c, 0x6f, 0x63, 0x6b, // "block"
		0x12, // RejectDuplicate
		0x0f, 0x64, 0x75, 0x70, 0x6c, 0x69, 0x63, 0x61,
		0x74, 0x65, 0x20, 0x62, 0x6c, 0x6f, 0x63, 0x6b, // "duplicate block"
		0x6f, 0xe2, 0x8c, 0x0a, 0xb6, 0xf1, 0xb3, 0x72,
		0xc1, 0xa6, 0xa2, 0x46, 0xae, 0x63, 0xf7, 0x4f,
		0x93, 0x1e, 0x83, 0x65, 0xe1, 0x5a, 0x08, 0x9c,
		0x68, 0xd6, 0x19, 0x00, 0x00, 0x00, 0x00, 0x00, // mainNetGenesisHash
	}

	tests := []struct {
		in       *MsgReject // Value to encode
		buf      []byte     // Wire encoding
		pver     uint32     // Protocol version for wire encoding
		max      int        // Max size of fixed buffer to induce errors
		writeErr error      // Expected write error
		readErr  error      // Expected read error
	}{
		// Latest protocol version with intentional read/write errors.
		// Force error in reject command.
		{baseReject, baseRejectEncoded, pver, 0, io.ErrShortWrite, io.EOF},
		// Force error in reject code.
		{baseReject, baseRejectEncoded, pver, 6, io.ErrShortWrite, io.EOF},
		// Force error in reject reason.
		{baseReject, baseRejectEncoded, pver, 7, io.ErrShortWrite, io.EOF},
		// Force error in reject hash.
		{baseReject, baseRejectEncoded, pver, 23, io.ErrShortWrite, io.EOF},
	}

	t.Logf("Running %d tests", len(tests))
	for i, test := range tests {
		// Encode to wire format.
		w := newFixedWriter(test.max)
		err := test.in.BtcEncode(w, test.pver)
		if !errors.Is(err, test.writeErr) {
			t.Errorf("BtcEncode #%d wrong error got: %v, want: %v", i, err,
				test.writeErr)
			continue
		}

		// Decode from wire format.
		var msg MsgReject
		r := newFixedReader(test.max, test.buf)
		err = msg.BtcDecode(r, test.pver)
		if !errors.Is(err, test.readErr) {
			t.Errorf("BtcDecode #%d wrong error got: %v, want: %v", i, err,
				test.readErr)
			continue
		}
	}
}