// Copyright 2012-2018 The NATS Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package server

import (
	"bytes"
	"testing"
)

func dummyClient() *client {
	return &client{srv: New(&defaultServerOptions)}
}

func dummyRouteClient() *client {
	return &client{srv: New(&defaultServerOptions), typ: ROUTER}
}

func TestParsePing(t *testing.T) {
	c := dummyClient()
	if c.state != OP_START {
		t.Fatalf("Expected OP_START vs %d\n", c.state)
	}
	ping := []byte("PING\r\n")
	err := c.parse(ping[:1])
	if err != nil || c.state != OP_P {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(ping[1:2])
	if err != nil || c.state != OP_PI {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(ping[2:3])
	if err != nil || c.state != OP_PIN {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(ping[3:4])
	if err != nil || c.state != OP_PING {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(ping[4:5])
	if err != nil || c.state != OP_PING {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(ping[5:6])
	if err != nil || c.state != OP_START {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(ping)
	if err != nil || c.state != OP_START {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	// Should tolerate spaces
	ping = []byte("PING  \r")
	err = c.parse(ping)
	if err != nil || c.state != OP_PING {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	c.state = OP_START
	ping = []byte("PING  \r  \n")
	err = c.parse(ping)
	if err != nil || c.state != OP_START {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
}

func TestParsePong(t *testing.T) {
	c := dummyClient()
	if c.state != OP_START {
		t.Fatalf("Expected OP_START vs %d\n", c.state)
	}
	pong := []byte("PONG\r\n")
	err := c.parse(pong[:1])
	if err != nil || c.state != OP_P {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(pong[1:2])
	if err != nil || c.state != OP_PO {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(pong[2:3])
	if err != nil || c.state != OP_PON {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(pong[3:4])
	if err != nil || c.state != OP_PONG {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(pong[4:5])
	if err != nil || c.state != OP_PONG {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(pong[5:6])
	if err != nil || c.state != OP_START {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	if c.ping.out != 0 {
		t.Fatalf("Unexpected ping.out value: %d vs 0\n", c.ping.out)
	}
	err = c.parse(pong)
	if err != nil || c.state != OP_START {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	if c.ping.out != 0 {
		t.Fatalf("Unexpected ping.out value: %d vs 0\n", c.ping.out)
	}
	// Should tolerate spaces
	pong = []byte("PONG  \r")
	err = c.parse(pong)
	if err != nil || c.state != OP_PONG {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	c.state = OP_START
	pong = []byte("PONG  \r  \n")
	err = c.parse(pong)
	if err != nil || c.state != OP_START {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	if c.ping.out != 0 {
		t.Fatalf("Unexpected ping.out value: %d vs 0\n", c.ping.out)
	}

	// Should be adjusting c.pout (Pings Outstanding): reset to 0
	c.state = OP_START
	c.ping.out = 10
	pong = []byte("PONG\r\n")
	err = c.parse(pong)
	if err != nil || c.state != OP_START {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	if c.ping.out != 0 {
		t.Fatalf("Unexpected ping.out: %d vs 0\n", c.ping.out)
	}
}

func TestParseConnect(t *testing.T) {
	c := dummyClient()
	connect := []byte("CONNECT {\"verbose\":false,\"pedantic\":true,\"tls_required\":false}\r\n")
	err := c.parse(connect)
	if err != nil || c.state != OP_START {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	// Check saved state
	if c.as != 8 {
		t.Fatalf("ArgStart state incorrect: 8 vs %d\n", c.as)
	}
}

func TestParseSub(t *testing.T) {
	c := dummyClient()
	sub := []byte("SUB foo 1\r")
	err := c.parse(sub)
	if err != nil || c.state != SUB_ARG {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	// Check saved state
	if c.as != 4 {
		t.Fatalf("ArgStart state incorrect: 4 vs %d\n", c.as)
	}
	if c.drop != 1 {
		t.Fatalf("Drop state incorrect: 1 vs %d\n", c.as)
	}
	if !bytes.Equal(sub[c.as:], []byte("foo 1\r")) {
		t.Fatalf("Arg state incorrect: %s\n", sub[c.as:])
	}
}

func TestParsePub(t *testing.T) {
	c := dummyClient()

	pub := []byte("PUB foo 5\r\nhello\r")
	err := c.parse(pub)
	if err != nil || c.state != MSG_END {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	if !bytes.Equal(c.pa.subject, []byte("foo")) {
		t.Fatalf("Did not parse subject correctly: 'foo' vs '%s'\n", string(c.pa.subject))
	}
	if c.pa.reply != nil {
		t.Fatalf("Did not parse reply correctly: 'nil' vs '%s'\n", string(c.pa.reply))
	}
	if c.pa.size != 5 {
		t.Fatalf("Did not parse msg size correctly: 5 vs %d\n", c.pa.size)
	}

	// Clear snapshots
	c.argBuf, c.msgBuf, c.state = nil, nil, OP_START

	pub = []byte("PUB foo.bar INBOX.22 11\r\nhello world\r")
	err = c.parse(pub)
	if err != nil || c.state != MSG_END {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	if !bytes.Equal(c.pa.subject, []byte("foo.bar")) {
		t.Fatalf("Did not parse subject correctly: 'foo' vs '%s'\n", string(c.pa.subject))
	}
	if !bytes.Equal(c.pa.reply, []byte("INBOX.22")) {
		t.Fatalf("Did not parse reply correctly: 'INBOX.22' vs '%s'\n", string(c.pa.reply))
	}
	if c.pa.size != 11 {
		t.Fatalf("Did not parse msg size correctly: 11 vs %d\n", c.pa.size)
	}
}

func TestParsePubArg(t *testing.T) {
	c := dummyClient()

	for _, test := range []struct {
		arg     string
		subject string
		reply   string
		size    int
		szb     string
	}{
		{arg: "a 2",
			subject: "a", reply: "", size: 2, szb: "2"},
		{arg: "a 222",
			subject: "a", reply: "", size: 222, szb: "222"},
		{arg: "foo 22",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: " foo 22",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: "foo 22 ",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: "foo   22",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: " foo 22 ",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: " foo   22 ",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: "foo bar 22",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: " foo bar 22",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: "foo bar 22 ",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: "foo  bar  22",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: " foo bar 22 ",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: "  foo   bar  22  ",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: "  foo   bar  2222  ",
			subject: "foo", reply: "bar", size: 2222, szb: "2222"},
		{arg: "  foo     2222  ",
			subject: "foo", reply: "", size: 2222, szb: "2222"},
		{arg: "a\t2",
			subject: "a", reply: "", size: 2, szb: "2"},
		{arg: "a\t222",
			subject: "a", reply: "", size: 222, szb: "222"},
		{arg: "foo\t22",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: "\tfoo\t22",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: "foo\t22\t",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: "foo\t\t\t22",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: "\tfoo\t22\t",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: "\tfoo\t\t\t22\t",
			subject: "foo", reply: "", size: 22, szb: "22"},
		{arg: "foo\tbar\t22",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: "\tfoo\tbar\t22",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: "foo\tbar\t22\t",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: "foo\t\tbar\t\t22",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: "\tfoo\tbar\t22\t",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: "\t \tfoo\t \t \tbar\t \t22\t \t",
			subject: "foo", reply: "bar", size: 22, szb: "22"},
		{arg: "\t\tfoo\t\t\tbar\t\t2222\t\t",
			subject: "foo", reply: "bar", size: 2222, szb: "2222"},
		{arg: "\t \tfoo\t \t \t\t\t2222\t \t",
			subject: "foo", reply: "", size: 2222, szb: "2222"},
	} {
		t.Run(test.arg, func(t *testing.T) {
			if err := c.processPub([]byte(test.arg)); err != nil {
				t.Fatalf("Unexpected parse error: %v\n", err)
			}
			if !bytes.Equal(c.pa.subject, []byte(test.subject)) {
				t.Fatalf("Mismatched subject: '%s'\n", c.pa.subject)
			}
			if !bytes.Equal(c.pa.reply, []byte(test.reply)) {
				t.Fatalf("Mismatched reply subject: '%s'\n", c.pa.reply)
			}
			if !bytes.Equal(c.pa.szb, []byte(test.szb)) {
				t.Fatalf("Bad size buf: '%s'\n", c.pa.szb)
			}
			if c.pa.size != test.size {
				t.Fatalf("Bad size: %d\n", c.pa.size)
			}
		})
	}
}

func TestParsePubBadSize(t *testing.T) {
	c := dummyClient()
	// Setup localized max payload
	c.mpay = 32768
	if err := c.processPub([]byte("foo 2222222222222222")); err == nil {
		t.Fatalf("Expected parse error for size too large")
	}
}

func TestParseMsg(t *testing.T) {
	c := dummyRouteClient()

	pub := []byte("MSG foo RSID:1:2 5\r\nhello\r")
	err := c.parse(pub)
	if err != nil || c.state != MSG_END {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	if !bytes.Equal(c.pa.subject, []byte("foo")) {
		t.Fatalf("Did not parse subject correctly: 'foo' vs '%s'\n", c.pa.subject)
	}
	if c.pa.reply != nil {
		t.Fatalf("Did not parse reply correctly: 'nil' vs '%s'\n", c.pa.reply)
	}
	if c.pa.size != 5 {
		t.Fatalf("Did not parse msg size correctly: 5 vs %d\n", c.pa.size)
	}
	if !bytes.Equal(c.pa.sid, []byte("RSID:1:2")) {
		t.Fatalf("Did not parse sid correctly: 'RSID:1:2' vs '%s'\n", c.pa.sid)
	}

	// Clear snapshots
	c.argBuf, c.msgBuf, c.state = nil, nil, OP_START

	pub = []byte("MSG foo.bar RSID:1:2 INBOX.22 11\r\nhello world\r")
	err = c.parse(pub)
	if err != nil || c.state != MSG_END {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	if !bytes.Equal(c.pa.subject, []byte("foo.bar")) {
		t.Fatalf("Did not parse subject correctly: 'foo' vs '%s'\n", c.pa.subject)
	}
	if !bytes.Equal(c.pa.reply, []byte("INBOX.22")) {
		t.Fatalf("Did not parse reply correctly: 'INBOX.22' vs '%s'\n", c.pa.reply)
	}
	if c.pa.size != 11 {
		t.Fatalf("Did not parse msg size correctly: 11 vs %d\n", c.pa.size)
	}
}

func testMsgArg(c *client, t *testing.T) {
	if !bytes.Equal(c.pa.subject, []byte("foobar")) {
		t.Fatalf("Mismatched subject: '%s'\n", c.pa.subject)
	}
	if !bytes.Equal(c.pa.szb, []byte("22")) {
		t.Fatalf("Bad size buf: '%s'\n", c.pa.szb)
	}
	if c.pa.size != 22 {
		t.Fatalf("Bad size: %d\n", c.pa.size)
	}
	if !bytes.Equal(c.pa.sid, []byte("RSID:22:1")) {
		t.Fatalf("Bad sid: '%s'\n", c.pa.sid)
	}
}

func TestParseMsgArg(t *testing.T) {
	c := dummyClient()
	if err := c.processMsgArgs([]byte("foobar RSID:22:1 22")); err != nil {
		t.Fatalf("Unexpected parse error: %v\n", err)
	}
	testMsgArg(c, t)
	if err := c.processMsgArgs([]byte(" foobar RSID:22:1 22")); err != nil {
		t.Fatalf("Unexpected parse error: %v\n", err)
	}
	testMsgArg(c, t)
	if err := c.processMsgArgs([]byte(" foobar   RSID:22:1 22 ")); err != nil {
		t.Fatalf("Unexpected parse error: %v\n", err)
	}
	testMsgArg(c, t)
	if err := c.processMsgArgs([]byte("foobar   RSID:22:1  \t22")); err != nil {
		t.Fatalf("Unexpected parse error: %v\n", err)
	}
	if err := c.processMsgArgs([]byte("foobar\t\tRSID:22:1\t22\r")); err != nil {
		t.Fatalf("Unexpected parse error: %v\n", err)
	}
	testMsgArg(c, t)
}

func TestParseMsgSpace(t *testing.T) {
	c := dummyRouteClient()

	// Ivan bug he found
	if err := c.parse([]byte("MSG \r\n")); err == nil {
		t.Fatalf("Expected parse error for MSG <SPC>")
	}

	c = dummyClient()

	// Anything with an M from a client should parse error
	if err := c.parse([]byte("M")); err == nil {
		t.Fatalf("Expected parse error for M* from a client")
	}
}

func TestShouldFail(t *testing.T) {
	wrongProtos := []string{
		"xxx",
		"Px", "PIx", "PINx", " PING",
		"POx", "PONx",
		"+x", "+Ox",
		"-x", "-Ex", "-ERx", "-ERRx",
		"Cx", "COx", "CONx", "CONNx", "CONNEx", "CONNECx", "CONNECx", "CONNECT \r\n",
		"PUx", "PUB foo\r\n", "PUB  \r\n", "PUB foo bar       \r\n",
		"PUB foo 2\r\nok \r\n", "PUB foo 2\r\nok\r \n",
		"Sx", "SUx", "SUB\r\n", "SUB  \r\n", "SUB foo\r\n",
		"SUB foo bar baz 22\r\n",
		"Ux", "UNx", "UNSx", "UNSUx", "UNSUBx", "UNSUBUNSUB 1\r\n", "UNSUB_2\r\n",
		"UNSUB_UNSUB_UNSUB 2\r\n", "UNSUB_\t2\r\n", "UNSUB\r\n", "UNSUB \r\n",
		"UNSUB          \t       \r\n",
		"Ix", "INx", "INFx", "INFO  \r\n",
	}
	for _, proto := range wrongProtos {
		c := dummyClient()
		if err := c.parse([]byte(proto)); err == nil {
			t.Fatalf("Should have received a parse error for: %v", proto)
		}
	}

	// Special case for MSG, type needs to not be client.
	wrongProtos = []string{"Mx", "MSx", "MSGx", "MSG  \r\n"}
	for _, proto := range wrongProtos {
		c := dummyClient()
		c.typ = ROUTER
		if err := c.parse([]byte(proto)); err == nil {
			t.Fatalf("Should have received a parse error for: %v", proto)
		}
	}
}

func TestProtoSnippet(t *testing.T) {
	sample := []byte("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")

	tests := []struct {
		input    int
		expected string
	}{
		{0, `"abcdefghijklmnopqrstuvwxyzABCDEF"`},
		{1, `"bcdefghijklmnopqrstuvwxyzABCDEFG"`},
		{2, `"cdefghijklmnopqrstuvwxyzABCDEFGH"`},
		{3, `"defghijklmnopqrstuvwxyzABCDEFGHI"`},
		{4, `"efghijklmnopqrstuvwxyzABCDEFGHIJ"`},
		{5, `"fghijklmnopqrstuvwxyzABCDEFGHIJK"`},
		{6, `"ghijklmnopqrstuvwxyzABCDEFGHIJKL"`},
		{7, `"hijklmnopqrstuvwxyzABCDEFGHIJKLM"`},
		{8, `"ijklmnopqrstuvwxyzABCDEFGHIJKLMN"`},
		{9, `"jklmnopqrstuvwxyzABCDEFGHIJKLMNO"`},
		{10, `"klmnopqrstuvwxyzABCDEFGHIJKLMNOP"`},
		{11, `"lmnopqrstuvwxyzABCDEFGHIJKLMNOPQ"`},
		{12, `"mnopqrstuvwxyzABCDEFGHIJKLMNOPQR"`},
		{13, `"nopqrstuvwxyzABCDEFGHIJKLMNOPQRS"`},
		{14, `"opqrstuvwxyzABCDEFGHIJKLMNOPQRST"`},
		{15, `"pqrstuvwxyzABCDEFGHIJKLMNOPQRSTU"`},
		{16, `"qrstuvwxyzABCDEFGHIJKLMNOPQRSTUV"`},
		{17, `"rstuvwxyzABCDEFGHIJKLMNOPQRSTUVW"`},
		{18, `"stuvwxyzABCDEFGHIJKLMNOPQRSTUVWX"`},
		{19, `"tuvwxyzABCDEFGHIJKLMNOPQRSTUVWXY"`},
		{20, `"uvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"`},
		{21, `"vwxyzABCDEFGHIJKLMNOPQRSTUVWXY"`},
		{22, `"wxyzABCDEFGHIJKLMNOPQRSTUVWXY"`},
		{23, `"xyzABCDEFGHIJKLMNOPQRSTUVWXY"`},
		{24, `"yzABCDEFGHIJKLMNOPQRSTUVWXY"`},
		{25, `"zABCDEFGHIJKLMNOPQRSTUVWXY"`},
		{26, `"ABCDEFGHIJKLMNOPQRSTUVWXY"`},
		{27, `"BCDEFGHIJKLMNOPQRSTUVWXY"`},
		{28, `"CDEFGHIJKLMNOPQRSTUVWXY"`},
		{29, `"DEFGHIJKLMNOPQRSTUVWXY"`},
		{30, `"EFGHIJKLMNOPQRSTUVWXY"`},
		{31, `"FGHIJKLMNOPQRSTUVWXY"`},
		{32, `"GHIJKLMNOPQRSTUVWXY"`},
		{33, `"HIJKLMNOPQRSTUVWXY"`},
		{34, `"IJKLMNOPQRSTUVWXY"`},
		{35, `"JKLMNOPQRSTUVWXY"`},
		{36, `"KLMNOPQRSTUVWXY"`},
		{37, `"LMNOPQRSTUVWXY"`},
		{38, `"MNOPQRSTUVWXY"`},
		{39, `"NOPQRSTUVWXY"`},
		{40, `"OPQRSTUVWXY"`},
		{41, `"PQRSTUVWXY"`},
		{42, `"QRSTUVWXY"`},
		{43, `"RSTUVWXY"`},
		{44, `"STUVWXY"`},
		{45, `"TUVWXY"`},
		{46, `"UVWXY"`},
		{47, `"VWXY"`},
		{48, `"WXY"`},
		{49, `"XY"`},
		{50, `"Y"`},
		{51, `""`},
		{52, `""`},
		{53, `""`},
		{54, `""`},
	}

	for _, tt := range tests {
		got := protoSnippet(tt.input, sample)
		if tt.expected != got {
			t.Errorf("Expected protocol snippet to be %s when start=%d but got %s\n", tt.expected, tt.input, got)
		}
	}
}

func TestParseOK(t *testing.T) {
	c := dummyClient()
	if c.state != OP_START {
		t.Fatalf("Expected OP_START vs %d\n", c.state)
	}
	okProto := []byte("+OK\r\n")
	err := c.parse(okProto[:1])
	if err != nil || c.state != OP_PLUS {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(okProto[1:2])
	if err != nil || c.state != OP_PLUS_O {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(okProto[2:3])
	if err != nil || c.state != OP_PLUS_OK {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(okProto[3:4])
	if err != nil || c.state != OP_PLUS_OK {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
	err = c.parse(okProto[4:5])
	if err != nil || c.state != OP_START {
		t.Fatalf("Unexpected: %d : %v\n", c.state, err)
	}
}