/// <summary>
/// Returns a copy of a frame based on its index. If the index is not valid, the method returns NULL.
/// The return value is a copy of the original object to ensure it is immutable.
/// </summary>
public BowlingFrame GetFrame(int index)
{
// Check if the given index is valid. If yes - return a copy of BowlingFrame, otherwise, return NULL.
return((BowlingGameExtenstions.IsIndexExists(Frames, index)) ?
new BowlingFrame(BowlingGameExtenstions.GetItemFromArray <BowlingFrame>(Frames, index)) :
null);
}
/// <summary>
/// Calculate the score of each frame, starting from the first until the last.
/// If the frame's score cannot be determined yet (Split or Strike) - keep the score value as NULL.
/// </summary>
public int?[] GetFramesScores()
{
int?[] scores = new int?[Frames.Length];
// fill the scores array, until the last legit round
for (int i = 0; i < Frames.Length && i < BowlingGameExtenstions.NUM_OF_REGULAR_ROUNDS; i++)
{
// Scenario 1: a simple frame
if (Frames[i].FrameType == FrameTypeEnum.Normal)
{
scores[i] = Frames[i].NumOfDroppedPins;
}
// Scenario 2: Handle spare: check if the subsequent frame exists, only then calculate the score of this frame
else if (Frames[i].FrameType == FrameTypeEnum.Spare &&
BowlingGameExtenstions.IsIndexExists <BowlingFrame>(Frames, i + 1))
{
scores[i] = ((GetFrame(i + 1)?.Try1) ?? 0) + Frames[i].NumOfDroppedPins;
}
// Scenario 3: Handle two consecutive strikes (check if there is a frame in the subsequent throw after the second strike).
// if not - do not calculate the score of this frame
else if (Frames[i].FrameType == FrameTypeEnum.Strike &&
GetFrameType(i + 1) == FrameTypeEnum.Strike &&
BowlingGameExtenstions.IsIndexExists <BowlingFrame>(Frames, i + 2))
{
scores[i] = ((GetFrame(i + 1)?.Try1) ?? 0) + ((GetFrame(i + 2)?.Try1) ?? 0) + Frames[i].NumOfDroppedPins;
}
// Scenario 4: Handle one strikes: check if the subsequent frame exists, only then calculate the score of this frame
else if (Frames[i].FrameType == FrameTypeEnum.Strike &&
GetFrameType(i + 1) != FrameTypeEnum.Strike &&
BowlingGameExtenstions.IsIndexExists <BowlingFrame>(Frames, i + 1))
{
scores[i] = ((GetFrame(i + 1)?.Try1) ?? 0) + ((GetFrame(i + 1)?.Try2) ?? 0) + Frames[i].NumOfDroppedPins;
}
// Scenario 5: default (not a realistic scenario (unless the Frames includes an invalid items or the loop is overrun)
else
{
scores[i] = null;
}
}
// Handle the edge case when the last round is Strike (since there scenario no. 3 doesn't handle it).
if (Frames.Length == (BowlingGameExtenstions.NUM_OF_REGULAR_ROUNDS + BowlingGameExtenstions.EXTRA_ROUNDS))
{
if (GetFrameType(BowlingGameExtenstions.NUM_OF_REGULAR_ROUNDS - 1) == FrameTypeEnum.Strike)
{
scores[BowlingGameExtenstions.NUM_OF_REGULAR_ROUNDS - 1] = Frames[BowlingGameExtenstions.NUM_OF_REGULAR_ROUNDS + BowlingGameExtenstions.EXTRA_ROUNDS - 1].NumOfDroppedPins +
Frames[BowlingGameExtenstions.NUM_OF_REGULAR_ROUNDS - 1].NumOfDroppedPins;
}
}
return(scores);
}