console_progress.py

"""Small dependency-free progress reporting for long command-line analyses."""

from __future__ import annotations

import sys
import time


class ProgressBar:
    """Print a compact progress bar at five-percentage-point intervals."""

    def __init__(self, label: str, total: int, enabled: bool = True) -> None:
        self.label = label
        self.total = total
        self.enabled = enabled and total > 0
        self.completed = 0
        self.started = time.perf_counter()
        self.last_percent = -1
        if self.enabled:
            self._display(force=True)

    def advance(self) -> None:
        if not self.enabled:
            return
        self.completed = min(self.completed + 1, self.total)
        self._display(force=self.completed == self.total)

    def finish(self) -> None:
        if not self.enabled:
            return
        if self.completed < self.total:
            self.completed = self.total
            self._display(force=True)
        sys.stderr.flush()
        self.enabled = False

    def _display(self, force: bool = False) -> None:
        percent = int(100 * self.completed / self.total)
        if (
            not force
            and self.last_percent >= 0
            and percent // 5 == self.last_percent // 5
        ):
            return
        self.last_percent = percent
        width = 30
        filled = int(width * self.completed / self.total)
        bar = "#" * filled + "-" * (width - filled)
        elapsed = time.perf_counter() - self.started
        if self.completed:
            eta = elapsed * (self.total - self.completed) / self.completed
            eta_text = f"; ETA {eta:.0f}s"
        else:
            eta_text = ""
        sys.stderr.write(
            f"{self.label}: [{bar}] {percent:3d}% "
            f"({self.completed}/{self.total}; {elapsed:.0f}s{eta_text})\n"
        )
        sys.stderr.flush()