public async Task ProducesSolvableSequenceAfterSystematicSection()
{
var data = new byte[]
{
0x00,
0x01,
0x02,
0x03,
0x04,
0x05,
0x06,
0x07
};
var mixedSection = SliceHelpers.CreateGenerator(
data: data,
sliceSize: 2,
rngFactoryDelegate: () => new RandomAdapter(new Random(0)), // Seed Random so it's deterministic
isSystematic: true
).Skip(data.Length).Take(10).ToList();
var solver = new SliceSolver(2, data.Length);
foreach (var slice in mixedSection)
{
await solver.RememberAsync(slice);
}
var solution = await solver.TrySolveAsync();
Assert.IsNotNull(solution);
Assert.IsTrue(solution.SequenceEqual(data));
}
public async Task WorksEvenWhenSliceSizeAndNumberOfSlicesDoNotEvenlyDivideData()
{
var originalData = new []
{
(byte)'C',
(byte)'a',
(byte)'t'
};
Slice
slice1 = Slice.Create(
coefficients: new [] { true, false },
data: new [] { originalData[0], originalData[1] }
),
slice2 = Slice.Create(
coefficients: new [] { true, true },
data: new [] { (byte)(originalData[0] ^ originalData[2]), originalData[1] }
);
var solver = new SliceSolver(2, 3);
await solver.RememberAsync(slice2);
await solver.RememberAsync(slice1);
var solution = await solver.TrySolveAsync();
Assert.IsNotNull(solution, "Didn't find a solution");
Assert.AreEqual(solution.Length, 3, $"Found a solution of {solution.Length} bytes, instead of 3 bytes");
Assert.IsTrue(solution.SequenceEqual(originalData), "Found different solution than original data");
}
public async Task DoesNotSolvePrematurelyAsync()
{
var solver = new SliceSolver(1, 1);
var solution = await solver.TrySolveAsync();
Assert.IsNull(solution, "It created a solution from nothing");
}
public async Task PutsOneByteBackTogetherAsync()
{
const byte value = 0xF5;
var slice = Slice.Create(
coefficients: new [] { true },
data: new [] { value }
);
var solver = new SliceSolver(1, 1);
await solver.RememberAsync(slice);
var solution = await solver.TrySolveAsync();
Assert.IsNotNull(solution, "Didn't find a solution");
Assert.AreEqual(solution.Length, 1, $"Found a solution of {solution.Length} bytes, instead of 1 byte");
Assert.AreEqual(solution[0], value, $"Found the wrong solution: {solution[0]} instead of {value}");
}
public async Task PutsTwoSequentialSlicesBackTogetherAsync()
{
const byte
value1 = 0xFF,
value2 = 0x55;
Slice
slice1 = Slice.Create(
coefficients: new [] { true, false },
data: new [] { value1 }),
slice2 = Slice.Create(
coefficients: new [] { false, true },
data: new [] { value2 });
var solver = new SliceSolver(1, 2);
await solver.RememberAsync(slice1);
await solver.RememberAsync(slice2);
var solution = await solver.TrySolveAsync();
Assert.IsNotNull(solution, "Didn't find a solution");
Assert.AreEqual(solution.Length, 2, $"Found a solution of {solution.Length} bytes, instead of 2 bytes");
Assert.AreEqual(solution[0], value1, $"Found the wrong first byte: {solution[0]} instead of {value1}");
Assert.AreEqual(solution[1], value2, $"Found the wrong second byte: {solution[1]} instead of {value2}");
}