/* global describe, it */
var assert = require('assert');
var convert = require('../src/convert.js');

describe('convert', function() {
    describe('bytesToHex', function() {
        it('handles example 1', function() {
            assert.equal(convert.bytesToHex([0, 1, 2, 255]), '000102ff');
        })
    })

    describe('hexToBytes', function() {
        it('handles example 1', function() {
            assert.deepEqual(convert.hexToBytes('000102ff'), [0, 1, 2, 255]);
        })
    })

    it('converts from bytes to hex and back', function() {
        var bytes = [];
        for (var i=0 ; i<256 ; ++i) {
            bytes.push(i);
        }

        var hex = convert.bytesToHex(bytes);
        assert.equal(hex.length, 512);
        assert.deepEqual(convert.hexToBytes(hex), bytes);
    })

    describe('bytesToBase64', function() {
        it('passes RFC4648 test vectors', function() {
            // Test vectors from:
            // http://tools.ietf.org/html/rfc4648#page-12

            var b64 = function(s) {
                return convert.bytesToBase64(convert.stringToBytes(s))
            }

            assert.equal(b64(''), '')
            assert.equal(b64('f'), 'Zg==')
            assert.equal(b64('fo'), 'Zm8=')
            assert.equal(b64('foo'), 'Zm9v')
            assert.equal(b64('foob'), 'Zm9vYg==')
            assert.equal(b64('fooba'), 'Zm9vYmE=')
            assert.equal(b64('foobar'), 'Zm9vYmFy')
        })
    })

    describe('byte array and word array conversions', function(){
        var bytes, wordArray;

        beforeEach(function(){
            bytes = [
                98, 233, 7, 177, 92, 191, 39, 213, 66, 83,
                153, 235, 246, 240, 251, 80, 235, 184, 143, 24
            ]
            wordArray = {
                words: [1659439025, 1556031445, 1112775147, -151979184, -340226280],
                sigBytes: 20
            }
        })

        describe('bytesToWords', function() {
            it('works', function() {
                assert.deepEqual(convert.bytesToWordArray(bytes), wordArray)
            })
        })

        describe('bytesToWords', function() {
            it('works', function() {
                assert.deepEqual(convert.wordArrayToBytes(wordArray), bytes)
            })
        })
    })

    describe('numToVarInt', function() {
      describe('works', function() {
        var data = [
          0, 128, 252, // 8-bit
          256, 512, 1024, // 16-bit
          65541, // 32-bit
          4294967299, // 64-bit
        ]
        var expected = [
          [0], [128], [252], // 8-bit
          [253, 0, 1], [253, 0, 2], [253, 0, 4], // 16-bit
          [254, 5, 0, 1, 0], // 32-bit
          [255, 3, 0, 0, 0, 1, 0, 0, 0] // 64-bit
        ]

        for (var i = 0; i < data.length; ++i) {
          var actual = convert.numToVarInt(data[i])
          assert.deepEqual(actual, expected[i])
        }
      })
    })

    describe('varIntToNum', function() {
      it('works on valid input', function() {
        var data = [
          [0], [128], [252], // 8-bit
          [253, 0, 1], [253, 0, 2], [253, 0, 4], // 16-bit
          [254, 5, 0, 1, 0], // 32-bit
          [255, 3, 0, 0, 0, 1, 0, 0, 0] // 64-bit
        ]
        var expected = [
          0, 128, 252, // 8-bit
          256, 512, 1024, // 16-bit
          65541, // 32-bit
          4294967299, // 64-bit
        ]

        for (var i = 0; i < data.length; ++i) {
          var actual = convert.varIntToNum(data[i])
          assert.equal(actual.number, expected[i])
          assert.deepEqual(actual.bytes, data[i])
        }
      })

      it('uses only what is necessary', function() {
        var data = [
          [0, 99],
          [253, 0, 1, 99],
          [254, 5, 0, 1, 0, 99],
          [255, 3, 0, 0, 0, 1, 0, 0, 0, 99]
        ]
        var expected = [0, 256, 65541, 4294967299]

        for (var i = 0; i < data.length; ++i) {
          var actual = convert.varIntToNum(data[i])
          assert.equal(actual.number, expected[i])
          assert.deepEqual(actual.bytes, data[i].slice(0, -1))
        }
      })
    })

    describe('reverseEndian', function() {
        it('works', function() {
            var bigEndian = "6a4062273ac4f9ea4ffca52d9fd102b08f6c32faa0a4d1318e3a7b2e437bb9c7"
            var littleEdian = "c7b97b432e7b3a8e31d1a4a0fa326c8fb002d19f2da5fc4feaf9c43a2762406a"
            assert.deepEqual(convert.reverseEndian(bigEndian), littleEdian)
            assert.deepEqual(convert.reverseEndian(littleEdian), bigEndian)
        })
    })
})