public code v1

pygrex/utils/sliding_window.py

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+from typing import List, Optional, TypeVar, Generic, Iterator
+
+T = TypeVar("T")
+
+
+class SlidingWindow(Generic[T]):
+    """Class for creating and managing sliding windows over a sequence.
+
+    This class provides functionality to iterate through windows of a fixed size
+    over a sequence of items.
+    """
+
+    def __init__(self, sequence: List[T], window_size: int):
+        """Initialize the sliding window.
+
+        Args:
+            sequence: The sequence of items to slide over
+            window_size: The size of each window (must be positive)
+
+        Raises:
+            ValueError: If window_size is less than 1
+            TypeError: If sequence is not iterable
+        """
+        if window_size < 1:
+            raise ValueError("Window size must be at least 1")
+
+        if not hasattr(sequence, "__iter__"):
+            raise TypeError("Sequence must be iterable")
+
+        self.sequence = sequence
+        self.window_size = window_size
+        self.index = 0
+        self.max_index = len(sequence) - window_size + 1 if sequence else 0
+
+    def get_next_window(self) -> Optional[List[T]]:
+        """Return the next window and advance the current position.
+
+        Returns:
+            A list containing the next window of items, or None if all windows
+            have been processed.
+        """
+        if self.index >= self.max_index:
+            return None
+
+        window = self.sequence[self.index : self.index + self.window_size]
+        self.index += 1
+        return window
+
+    def reset(self) -> None:
+        """Reset the window position to the beginning of the sequence."""
+        self.index = 0
+
+    def has_next(self) -> bool:
+        """Check if there are more windows available.
+
+        Returns:
+            True if there are more windows, False otherwise.
+        """
+        return self.index < self.max_index
+
+    def __iter__(self) -> Iterator[List[T]]:
+        """Make the class iterable.
+
+        Returns:
+            An iterator over all windows in the sequence.
+        """
+        self.reset()
+        return self
+
+    def __next__(self) -> List[T]:
+        """Get the next window for iteration.
+
+        Returns:
+            The next window as a list.
+
+        Raises:
+            StopIteration: When all windows have been processed.
+        """
+        window = self.get_next_window()
+        if window is None:
+            raise StopIteration
+        return window
+
+    def __len__(self) -> int:
+        """Return the total number of windows.
+
+        Returns:
+            The number of complete windows in the sequence.
+        """
+        return max(0, self.max_index)