/*
  Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.

  Licensed under the Apache License, Version 2.0 (the "License").
  You may not use this file except in compliance with the License.
  A copy of the License is located at

      http://www.apache.org/licenses/LICENSE-2.0

  or in the "license" file accompanying this file. This file 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 cbor

import (
	"bytes"
	"strings"
	"testing"
)

func TestLexDecimal(t *testing.T) {
	cases := []struct {
		in, out string
		encoded []byte
	}{
		{in: "-1000000000001", out: "-1000000000001"},
		{in: "-999999999998", out: "-999999999998"},
		{in: "-123.0", out: "-1230E-1"},
		{in: "-123", out: "-123"},
		{in: "-90.01000", out: "-9001000E-5"},
		{in: "-90.0100", out: "-900100E-4"},
		{in: "-90.010", out: "-90010E-3"},
		{in: "-90.01", out: "-9001E-2"},
		{in: "-11.000", out: "-11000E-3"},
		{in: "-11.00", out: "-1100E-2"},
		{in: "-11.0", out: "-110E-1"},
		{in: "-11", out: "-11"},
		{in: "-10.100", out: "-10100E-3"},
		{in: "-10.10", out: "-1010E-2"},
		{in: "-10.1", out: "-101E-1"},
		{in: "-10.010", out: "-10010E-3"},
		{in: "-10.01", out: "-1001E-2"},
		{in: "-10.001", out: "-10001E-3"},
		{in: "-3.14", out: "-314E-2"},
		{in: "-2", out: "-2"},
		{in: "-1", out: "-1"},
		{in: "-0.1", out: "-1E-1"},
		{in: "-0.01", out: "-1E-2"},
		{in: "-0.001", out: "-1E-3"},
		{in: "-0.0001", out: "-1E-4"},
		{in: "-0.00001", out: "-1E-5"},
		{in: "-22234353.464363E-43534545", out: "-22234353464363E-43534551", encoded: fromHex("0x7e829848c8c569c775705f7fe0")},
		{in: "0", out: "0"},
		{in: "0.00001", out: "1E-5"},
		{in: "0.0001", out: "1E-4"},
		{in: "0.001", out: "1E-3"},
		{in: "0.01", out: "1E-2"},
		{in: "0.1", out: "1E-1"},
		{in: "1", out: "1"},
		{in: "1.519043396057566434978347919110056828178617793420044845009095883102266197154983036170458159785045013168790194150005772171485123776663026225265083906941746679973910405487712226922360572160109286090827076840438099560139704109021077055039800992783574226209489067204747368646064279454016947109162015587773374645982363407385318610580528401964567546584779984692390257012118847492632253017295152938061049334216698639782484923671333852898253917484438297806515060144054619575586755908264584998428966635833900328448897013161311192041184225731248515188720354249594803044541017997943733673275617711293386746906471936186661605920860928968943328237982074083977888182412651483608535562031694297058289536988244754588375618162121230365495345691015255028957668241560658402002255378192112746401695967255968778246414510329530913582678929506142265708375720504712549814629448365993242613061373583046901281817825417384505249197569842907151879339231499054003148135601842677695751809087592596946507113528743471045104423997476282338624005970522081700127468869151380640131536800078172950172445606480673750541462894055397499420148923999103971546156968314898287319971866608744671525743690473528323942745338438886549298899754829284582718694198133239949986632293934118351261598803084928864575827542573948274062057885778247343717195523808009809686102995991858298705780338006833410164829798137972194669364972243958207138283628313248174819322874644154437406662833820122947930072048521034645768459084715771457149574679024406949597278639059408919395313400229796162612035343061223639450398459653735214907021029784343593875497348473060433594883367192096557118929922580718994140625",
			out: "1519043396057566434978347919110056828178617793420044845009095883102266197154983036170458159785045013168790194150005772171485123776663026225265083906941746679973910405487712226922360572160109286090827076840438099560139704109021077055039800992783574226209489067204747368646064279454016947109162015587773374645982363407385318610580528401964567546584779984692390257012118847492632253017295152938061049334216698639782484923671333852898253917484438297806515060144054619575586755908264584998428966635833900328448897013161311192041184225731248515188720354249594803044541017997943733673275617711293386746906471936186661605920860928968943328237982074083977888182412651483608535562031694297058289536988244754588375618162121230365495345691015255028957668241560658402002255378192112746401695967255968778246414510329530913582678929506142265708375720504712549814629448365993242613061373583046901281817825417384505249197569842907151879339231499054003148135601842677695751809087592596946507113528743471045104423997476282338624005970522081700127468869151380640131536800078172950172445606480673750541462894055397499420148923999103971546156968314898287319971866608744671525743690473528323942745338438886549298899754829284582718694198133239949986632293934118351261598803084928864575827542573948274062057885778247343717195523808009809686102995991858298705780338006833410164829798137972194669364972243958207138283628313248174819322874644154437406662833820122947930072048521034645768459084715771457149574679024406949597278639059408919395313400229796162612035343061223639450398459653735214907021029784343593875497348473060433594883367192096557118929922580718994140625E-1641"},
		{in: "2", out: "2"},
		{in: "3.14", out: "314E-2", encoded: fromHex("0xc1518020")},
		{in: "3.141", out: "3141E-3", encoded: fromHex("0xc151870000")},
		{in: "10.001", out: "10001E-3"},
		{in: "10.01", out: "1001E-2"},
		{in: "10.010", out: "10010E-3"},
		{in: "10.1", out: "101E-1"},
		{in: "10.10", out: "1010E-2"},
		{in: "10.100", out: "10100E-3"},
		{in: "11", out: "11"},
		{in: "11.0", out: "110E-1"},
		{in: "11.00", out: "1100E-2"},
		{in: "11.000", out: "11000E-3"},
		{in: "90.01", out: "9001E-2"},
		{in: "90.010", out: "90010E-3"},
		{in: "90.0100", out: "900100E-4"},
		{in: "90.01000", out: "9001000E-5"},
		{in: "123", out: "123"},
		{in: "123.0", out: "1230E-1"},
		{in: "3.14E11", out: "314E9", encoded: fromHex("0xcc518020")},
		{in: "999999999999", out: "999999999999"},
		{in: "1000000000000", out: "1000000000000"},
		{in: "111122223333444445555.66667777", out: "11112222333344444555566667777E-8", encoded: fromHex("0xd51ec863ad59721c98dea6ac70e004")},
		{in: "111122223333444445555.66667778", out: "11112222333344444555566667778E-8", encoded: fromHex("0xd51ec863ad59721c98dea6ac718004")},
	}

	var last []byte
	for _, c := range cases {
		var buf bytes.Buffer
		var dec Decimal
		dec.SetString(c.in)
		wl, err := EncodeLexDecimal(&dec, &buf)

		if err != nil {
			t.Errorf("unexpected encoding error " + err.Error())
			continue
		}

		encoded := buf.Bytes()
		if c.encoded != nil {
			if wl != len(c.encoded) {
				t.Errorf("expected length %d, actual length %d", len(c.encoded), wl)
			}

			if bytes.Compare(c.encoded, encoded) != 0 {
				t.Errorf("expected=%v, actual=%v for %v\n", c.encoded, encoded, c.in)
			}
		}

		if last != nil && bytes.Compare(last, encoded) >= 0 {
			t.Errorf("expected %v to be greater than or equal to last", c.in)
		}
		last = encoded

		actual, err := DecodeLexDecimal(&buf)
		if err != nil {
			t.Errorf("unexpected decoding error " + err.Error())
			continue
		}

		if strings.Compare(c.out, actual.String()) != 0 {
			t.Errorf("expected=%s, actual=%v", c.out, actual)
		}
	}
}

func BenchmarkLexDecimalEncode(b *testing.B) {
	dec := new(Decimal)
	dec.SetString("123456789.123")
	var buf bytes.Buffer
	b.ResetTimer()

	for i := 0; i < b.N; i++ {
		if _, err := EncodeLexDecimal(dec, &buf); err != nil {
			b.Errorf("unexpected error %v", err)
		}
		buf.Reset()
	}
}

func BenchmarkLexDecimalDecode(b *testing.B) {
	dec := new(Decimal)
	dec.SetString("123456789.123")
	var buf bytes.Buffer
	if _, err := EncodeLexDecimal(dec, &buf); err != nil {
		b.Errorf("unexpected error %v", err)
	}
	br := bytes.NewReader(buf.Bytes())
	b.ResetTimer()

	for i := 0; i < b.N; i++ {
		if _, err := DecodeLexDecimal(br); err != nil {
			b.Errorf("unexpected error %v", err)
		}
		br.Seek(0, 0)
	}
}