// Copyright (c) 2013 Conformal Systems LLC.
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.

package btcec_test

import (
	"bytes"
	"crypto/ecdsa"
	"github.com/conformal/btcec"
	"github.com/davecgh/go-spew/spew"
	"testing"
)

type privKeyTest struct {
	name string
	key  []byte
}

type pubKeyTest struct {
	name    string
	key     []byte
	format  byte
	isValid bool
}

var privKeyTests = []privKeyTest{
	privKeyTest{
		name: "check curve",
		key: []byte{
			0xea, 0xf0, 0x2c, 0xa3, 0x48, 0xc5, 0x24, 0xe6,
			0x39, 0x26, 0x55, 0xba, 0x4d, 0x29, 0x60, 0x3c,
			0xd1, 0xa7, 0x34, 0x7d, 0x9d, 0x65, 0xcf, 0xe9,
			0x3c, 0xe1, 0xeb, 0xff, 0xdc, 0xa2, 0x26, 0x94,
		},
	},
}

var pubKeyTests = []pubKeyTest{
	// pubkey from bitcoin blockchain tx
	// 0437cd7f8525ceed2324359c2d0ba26006d92d85
	pubKeyTest{
		name: "uncompressed ok",
		key: []byte{0x04, 0x11, 0xdb, 0x93, 0xe1, 0xdc, 0xdb, 0x8a,
			0x01, 0x6b, 0x49, 0x84, 0x0f, 0x8c, 0x53, 0xbc, 0x1e,
			0xb6, 0x8a, 0x38, 0x2e, 0x97, 0xb1, 0x48, 0x2e, 0xca,
			0xd7, 0xb1, 0x48, 0xa6, 0x90, 0x9a, 0x5c, 0xb2, 0xe0,
			0xea, 0xdd, 0xfb, 0x84, 0xcc, 0xf9, 0x74, 0x44, 0x64,
			0xf8, 0x2e, 0x16, 0x0b, 0xfa, 0x9b, 0x8b, 0x64, 0xf9,
			0xd4, 0xc0, 0x3f, 0x99, 0x9b, 0x86, 0x43, 0xf6, 0x56,
			0xb4, 0x12, 0xa3,
		},
		isValid: true,
		format:  btcec.TstPubkeyUncompressed,
	},
	pubKeyTest{
		name: "uncompressed x changed",
		key: []byte{0x04, 0x15, 0xdb, 0x93, 0xe1, 0xdc, 0xdb, 0x8a,
			0x01, 0x6b, 0x49, 0x84, 0x0f, 0x8c, 0x53, 0xbc, 0x1e,
			0xb6, 0x8a, 0x38, 0x2e, 0x97, 0xb1, 0x48, 0x2e, 0xca,
			0xd7, 0xb1, 0x48, 0xa6, 0x90, 0x9a, 0x5c, 0xb2, 0xe0,
			0xea, 0xdd, 0xfb, 0x84, 0xcc, 0xf9, 0x74, 0x44, 0x64,
			0xf8, 0x2e, 0x16, 0x0b, 0xfa, 0x9b, 0x8b, 0x64, 0xf9,
			0xd4, 0xc0, 0x3f, 0x99, 0x9b, 0x86, 0x43, 0xf6, 0x56,
			0xb4, 0x12, 0xa3,
		},
		isValid: false,
	},
	pubKeyTest{
		name: "uncompressed y changed",
		key: []byte{0x04, 0x11, 0xdb, 0x93, 0xe1, 0xdc, 0xdb, 0x8a,
			0x01, 0x6b, 0x49, 0x84, 0x0f, 0x8c, 0x53, 0xbc, 0x1e,
			0xb6, 0x8a, 0x38, 0x2e, 0x97, 0xb1, 0x48, 0x2e, 0xca,
			0xd7, 0xb1, 0x48, 0xa6, 0x90, 0x9a, 0x5c, 0xb2, 0xe0,
			0xea, 0xdd, 0xfb, 0x84, 0xcc, 0xf9, 0x74, 0x44, 0x64,
			0xf8, 0x2e, 0x16, 0x0b, 0xfa, 0x9b, 0x8b, 0x64, 0xf9,
			0xd4, 0xc0, 0x3f, 0x99, 0x9b, 0x86, 0x43, 0xf6, 0x56,
			0xb4, 0x12, 0xa4,
		},
		isValid: false,
	},
	pubKeyTest{
		name: "uncompressed claims compressed",
		key: []byte{0x03, 0x11, 0xdb, 0x93, 0xe1, 0xdc, 0xdb, 0x8a,
			0x01, 0x6b, 0x49, 0x84, 0x0f, 0x8c, 0x53, 0xbc, 0x1e,
			0xb6, 0x8a, 0x38, 0x2e, 0x97, 0xb1, 0x48, 0x2e, 0xca,
			0xd7, 0xb1, 0x48, 0xa6, 0x90, 0x9a, 0x5c, 0xb2, 0xe0,
			0xea, 0xdd, 0xfb, 0x84, 0xcc, 0xf9, 0x74, 0x44, 0x64,
			0xf8, 0x2e, 0x16, 0x0b, 0xfa, 0x9b, 0x8b, 0x64, 0xf9,
			0xd4, 0xc0, 0x3f, 0x99, 0x9b, 0x86, 0x43, 0xf6, 0x56,
			0xb4, 0x12, 0xa3,
		},
		isValid: false,
	},
	pubKeyTest{
		name: "uncompressed as hybrid ok",
		key: []byte{0x07, 0x11, 0xdb, 0x93, 0xe1, 0xdc, 0xdb, 0x8a,
			0x01, 0x6b, 0x49, 0x84, 0x0f, 0x8c, 0x53, 0xbc, 0x1e,
			0xb6, 0x8a, 0x38, 0x2e, 0x97, 0xb1, 0x48, 0x2e, 0xca,
			0xd7, 0xb1, 0x48, 0xa6, 0x90, 0x9a, 0x5c, 0xb2, 0xe0,
			0xea, 0xdd, 0xfb, 0x84, 0xcc, 0xf9, 0x74, 0x44, 0x64,
			0xf8, 0x2e, 0x16, 0x0b, 0xfa, 0x9b, 0x8b, 0x64, 0xf9,
			0xd4, 0xc0, 0x3f, 0x99, 0x9b, 0x86, 0x43, 0xf6, 0x56,
			0xb4, 0x12, 0xa3,
		},
		isValid: true,
		format:  btcec.TstPubkeyHybrid,
	},
	pubKeyTest{
		name: "uncompressed as hybrid wrong",
		key: []byte{0x06, 0x11, 0xdb, 0x93, 0xe1, 0xdc, 0xdb, 0x8a,
			0x01, 0x6b, 0x49, 0x84, 0x0f, 0x8c, 0x53, 0xbc, 0x1e,
			0xb6, 0x8a, 0x38, 0x2e, 0x97, 0xb1, 0x48, 0x2e, 0xca,
			0xd7, 0xb1, 0x48, 0xa6, 0x90, 0x9a, 0x5c, 0xb2, 0xe0,
			0xea, 0xdd, 0xfb, 0x84, 0xcc, 0xf9, 0x74, 0x44, 0x64,
			0xf8, 0x2e, 0x16, 0x0b, 0xfa, 0x9b, 0x8b, 0x64, 0xf9,
			0xd4, 0xc0, 0x3f, 0x99, 0x9b, 0x86, 0x43, 0xf6, 0x56,
			0xb4, 0x12, 0xa3,
		},
		isValid: false,
	},
	// from tx 0b09c51c51ff762f00fb26217269d2a18e77a4fa87d69b3c363ab4df16543f20
	pubKeyTest{
		name: "compressed ok (ybit = 0)",
		key: []byte{0x02, 0xce, 0x0b, 0x14, 0xfb, 0x84, 0x2b, 0x1b,
			0xa5, 0x49, 0xfd, 0xd6, 0x75, 0xc9, 0x80, 0x75, 0xf1,
			0x2e, 0x9c, 0x51, 0x0f, 0x8e, 0xf5, 0x2b, 0xd0, 0x21,
			0xa9, 0xa1, 0xf4, 0x80, 0x9d, 0x3b, 0x4d,
		},
		isValid: true,
		format:  btcec.TstPubkeyCompressed,
	},
	// from tx fdeb8e72524e8dab0da507ddbaf5f88fe4a933eb10a66bc4745bb0aa11ea393c
	pubKeyTest{
		name: "compressed ok (ybit = 1)",
		key: []byte{0x03, 0x26, 0x89, 0xc7, 0xc2, 0xda, 0xb1, 0x33,
			0x09, 0xfb, 0x14, 0x3e, 0x0e, 0x8f, 0xe3, 0x96, 0x34,
			0x25, 0x21, 0x88, 0x7e, 0x97, 0x66, 0x90, 0xb6, 0xb4,
			0x7f, 0x5b, 0x2a, 0x4b, 0x7d, 0x44, 0x8e,
		},
		isValid: true,
		format:  btcec.TstPubkeyCompressed,
	},
	pubKeyTest{
		name: "compressed claims uncompressed (ybit = 0)",
		key: []byte{0x04, 0xce, 0x0b, 0x14, 0xfb, 0x84, 0x2b, 0x1b,
			0xa5, 0x49, 0xfd, 0xd6, 0x75, 0xc9, 0x80, 0x75, 0xf1,
			0x2e, 0x9c, 0x51, 0x0f, 0x8e, 0xf5, 0x2b, 0xd0, 0x21,
			0xa9, 0xa1, 0xf4, 0x80, 0x9d, 0x3b, 0x4d,
		},
		isValid: false,
	},
	pubKeyTest{
		name: "compressed claims uncompressed (ybit = 1)",
		key: []byte{0x05, 0x26, 0x89, 0xc7, 0xc2, 0xda, 0xb1, 0x33,
			0x09, 0xfb, 0x14, 0x3e, 0x0e, 0x8f, 0xe3, 0x96, 0x34,
			0x25, 0x21, 0x88, 0x7e, 0x97, 0x66, 0x90, 0xb6, 0xb4,
			0x7f, 0x5b, 0x2a, 0x4b, 0x7d, 0x44, 0x8e,
		},
		isValid: false,
	},
	pubKeyTest{
		name:    "wrong length)",
		key:     []byte{0x05},
		isValid: false,
	},
	pubKeyTest{
		name: "X == P",
		key: []byte{0x04, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFC, 0x2F, 0xb2, 0xe0,
			0xea, 0xdd, 0xfb, 0x84, 0xcc, 0xf9, 0x74, 0x44, 0x64,
			0xf8, 0x2e, 0x16, 0x0b, 0xfa, 0x9b, 0x8b, 0x64, 0xf9,
			0xd4, 0xc0, 0x3f, 0x99, 0x9b, 0x86, 0x43, 0xf6, 0x56,
			0xb4, 0x12, 0xa3,
		},
		isValid: false,
	},
	pubKeyTest{
		name: "X > P",
		key: []byte{0x04, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFD, 0x2F, 0xb2, 0xe0,
			0xea, 0xdd, 0xfb, 0x84, 0xcc, 0xf9, 0x74, 0x44, 0x64,
			0xf8, 0x2e, 0x16, 0x0b, 0xfa, 0x9b, 0x8b, 0x64, 0xf9,
			0xd4, 0xc0, 0x3f, 0x99, 0x9b, 0x86, 0x43, 0xf6, 0x56,
			0xb4, 0x12, 0xa3,
		},
		isValid: false,
	},
	pubKeyTest{
		name: "Y == P",
		key: []byte{0x04, 0x11, 0xdb, 0x93, 0xe1, 0xdc, 0xdb, 0x8a,
			0x01, 0x6b, 0x49, 0x84, 0x0f, 0x8c, 0x53, 0xbc, 0x1e,
			0xb6, 0x8a, 0x38, 0x2e, 0x97, 0xb1, 0x48, 0x2e, 0xca,
			0xd7, 0xb1, 0x48, 0xa6, 0x90, 0x9a, 0x5c, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xFF,
			0xFF, 0xFC, 0x2F,
		},
		isValid: false,
	},
	pubKeyTest{
		name: "Y > P",
		key: []byte{0x04, 0x11, 0xdb, 0x93, 0xe1, 0xdc, 0xdb, 0x8a,
			0x01, 0x6b, 0x49, 0x84, 0x0f, 0x8c, 0x53, 0xbc, 0x1e,
			0xb6, 0x8a, 0x38, 0x2e, 0x97, 0xb1, 0x48, 0x2e, 0xca,
			0xd7, 0xb1, 0x48, 0xa6, 0x90, 0x9a, 0x5c, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xFF,
			0xFF, 0xFD, 0x2F,
		},
		isValid: false,
	},
}

func TestPrivKeys(t *testing.T) {
	for _, test := range privKeyTests {
		x, y := btcec.S256().ScalarBaseMult(test.key)
		pub := (*btcec.PublicKey)(&ecdsa.PublicKey{
			Curve: btcec.S256(),
			X:     x,
			Y:     y,
		})
		_, err := btcec.ParsePubKey(pub.SerializeUncompressed(), btcec.S256())
		if err != nil {
			t.Errorf("%s privkey: %v", test.name, err)
			continue
		}
	}
}

func TestPubKeys(t *testing.T) {
	for _, test := range pubKeyTests {
		pk, err := btcec.ParsePubKey(test.key, btcec.S256())
		if err != nil {
			if test.isValid {
				t.Errorf("%s pubkey failed when shouldn't %v",
					test.name, err)
			}
			continue
		}
		if !test.isValid {
			t.Errorf("%s counted as valid when it should fail",
				test.name)
			continue
		}
		var pkStr []byte
		switch test.format {
		case btcec.TstPubkeyUncompressed:
			pkStr = (*btcec.PublicKey)(pk).SerializeUncompressed()
		case btcec.TstPubkeyCompressed:
			pkStr = (*btcec.PublicKey)(pk).SerializeCompressed()
		case btcec.TstPubkeyHybrid:
			pkStr = (*btcec.PublicKey)(pk).SerializeHybrid()
		}
		if !bytes.Equal(test.key, pkStr) {
			t.Errorf("%s pubkey: serialized keys do not match.",
				test.name)
			spew.Dump(test.key)
			spew.Dump(pkStr)
		}
	}
}

func TestPad(t *testing.T) {
	tests := []struct {
		name     string // Short name to describe the test.
		inSize   int    // The size to pad to.
		inBytes  []byte // The input bytes to pad.
		expected []byte // The expected padded result.
	}{
		{
			name:   "same size - no padding needed",
			inSize: 32,
			inBytes: []byte{
				0xce, 0x0b, 0x14, 0xfb, 0x84, 0x2b, 0x1b, 0xa5,
				0x49, 0xfd, 0xd6, 0x75, 0xc9, 0x80, 0x75, 0xf1,
				0x2e, 0x9c, 0x51, 0x0f, 0x8e, 0xf5, 0x2b, 0xd0,
				0x21, 0xa9, 0xa1, 0xf4, 0x80, 0x9d, 0x3b, 0x4d,
			},
			expected: []byte{
				0xce, 0x0b, 0x14, 0xfb, 0x84, 0x2b, 0x1b, 0xa5,
				0x49, 0xfd, 0xd6, 0x75, 0xc9, 0x80, 0x75, 0xf1,
				0x2e, 0x9c, 0x51, 0x0f, 0x8e, 0xf5, 0x2b, 0xd0,
				0x21, 0xa9, 0xa1, 0xf4, 0x80, 0x9d, 0x3b, 0x4d,
			},
		},
		{
			name:   "short 1 byte",
			inSize: 32,
			inBytes: []byte{
				0x0b, 0x14, 0xfb, 0x84, 0x2b, 0x1b, 0xa5,
				0x49, 0xfd, 0xd6, 0x75, 0xc9, 0x80, 0x75, 0xf1,
				0x2e, 0x9c, 0x51, 0x0f, 0x8e, 0xf5, 0x2b, 0xd0,
				0x21, 0xa9, 0xa1, 0xf4, 0x80, 0x9d, 0x3b, 0x4d,
			},
			expected: []byte{
				0x00, 0x0b, 0x14, 0xfb, 0x84, 0x2b, 0x1b, 0xa5,
				0x49, 0xfd, 0xd6, 0x75, 0xc9, 0x80, 0x75, 0xf1,
				0x2e, 0x9c, 0x51, 0x0f, 0x8e, 0xf5, 0x2b, 0xd0,
				0x21, 0xa9, 0xa1, 0xf4, 0x80, 0x9d, 0x3b, 0x4d,
			},
		},
		{
			name:   "more bytes than pad size",
			inSize: 31,
			inBytes: []byte{
				0xce, 0x0b, 0x14, 0xfb, 0x84, 0x2b, 0x1b, 0xa5,
				0x49, 0xfd, 0xd6, 0x75, 0xc9, 0x80, 0x75, 0xf1,
				0x2e, 0x9c, 0x51, 0x0f, 0x8e, 0xf5, 0x2b, 0xd0,
				0x21, 0xa9, 0xa1, 0xf4, 0x80, 0x9d, 0x3b, 0x4d,
			},
			expected: []byte{
				0xce, 0x0b, 0x14, 0xfb, 0x84, 0x2b, 0x1b, 0xa5,
				0x49, 0xfd, 0xd6, 0x75, 0xc9, 0x80, 0x75, 0xf1,
				0x2e, 0x9c, 0x51, 0x0f, 0x8e, 0xf5, 0x2b, 0xd0,
				0x21, 0xa9, 0xa1, 0xf4, 0x80, 0x9d, 0x3b, 0x4d,
			},
		},
	}

	t.Logf("Running %d tests.", len(tests))
	for i, test := range tests {
		result := btcec.TstPad(test.inSize, test.inBytes)
		if !bytes.Equal(result, test.expected) {
			t.Errorf("pad #%d (%s) unexpected result:\n"+
				"got:  %x\nwant: %x", i, test.name, result,
				test.expected)
		}
	}
}