"""A refresh thread keeps elapsed time moving even during native processing."""
import time

from rich.console import Console
from rich.progress import (BarColumn, Progress, SpinnerColumn, TaskProgressColumn,
                           TextColumn, TimeElapsedColumn, TimeRemainingColumn)


class Display:
    def __init__(self):
        self.console = Console(stderr=True)
        self.progress = Progress(SpinnerColumn(), TextColumn("{task.description}"),
                                 BarColumn(), TaskProgressColumn(), TimeElapsedColumn(),
                                 TimeRemainingColumn(), console=self.console,
                                 refresh_per_second=5, disable=not self.console.is_terminal)
        self.task = None
        self.stage = ""
        self.started = time.monotonic()
        self.last_print = 0.0

    def __enter__(self):
        self.progress.start()
        return self

    def __exit__(self, *args):
        self.progress.stop()

    def update(self, stage, completed=None, total=None):
        changed = stage != self.stage
        if changed:
            if self.task is not None:
                self.progress.remove_task(self.task)
            self.task = self.progress.add_task(stage, total=total)
            self.stage = stage
        self.progress.update(self.task, completed=completed if total else 0, total=total)
        now = time.monotonic()
        if not self.console.is_terminal and (changed or now - self.last_print >= 5):
            fraction = f" {min(100, 100 * (completed or 0) / total):.0f}%" if total else ""
            self.console.print(f"[{now - self.started:7.1f}s] {stage}{fraction}", markup=False)
            self.last_print = now