import asyncio
from typing import List, Optional

from rich.console import Console, Group
from rich.live import Live
from rich.panel import Panel
from rich.progress_bar import ProgressBar
from rich.table import Table
from rich.text import Text

from bot.storage import Storage

_TYPE_LABELS = {"guild": "server", "group_dm": "group", "dm": "DM"}


def _render(stats: List[dict], friend_label: Optional[str] = None, status: Optional[str] = None) -> Panel:
    table = Table(expand=True)
    table.add_column("Target")
    table.add_column("Type")
    table.add_column("Progress", ratio=1)
    table.add_column("Reacted/Found", justify="right")
    table.add_column("Last reaction (UTC)")

    total_reacted = 0
    total_found = 0
    for row in stats:
        reacted = row["reaction_count"]
        found = max(row["messages_found"], reacted)  # found can never be less than reacted
        total_reacted += reacted
        total_found += found

        bar = ProgressBar(total=max(found, reacted, 1), completed=reacted, width=None)
        table.add_row(
            row["name"] or row["target_id"],
            _TYPE_LABELS.get(row["target_type"], row["target_type"]),
            bar,
            f"{reacted}/{found}",
            row["last_reaction_at"] or "-",
        )

    if not stats:
        table.add_row("(no targets discovered yet)", "-", "-", "-", "-")

    content = table
    if status:
        content = Group(table, Text(f"▸ {status}", style="dim italic"))

    who = f" for {friend_label}" if friend_label else ""
    return Panel(content, title=f"Reaction stats{who} — total: {total_reacted}/{total_found}", border_style="cyan")


class StatsDisplay:
    """A stats panel pinned to the bottom of the terminal, with normal
    log/print output scrolling above it (via rich.live.Live)."""

    def __init__(self, console: Console, storage: Storage):
        self.console = console
        self.storage = storage
        self.friend_label: Optional[str] = None
        self.status: str = "Starting..."
        self._last_stats: List[dict] = []
        self._live = Live(
            _render([], None, self.status),
            console=console,
            refresh_per_second=4,
            transient=False,
        )

    def __enter__(self):
        self._live.__enter__()
        return self

    def __exit__(self, *exc_info):
        return self._live.__exit__(*exc_info)

    def set_friend(self, label: str) -> None:
        self.friend_label = label

    def set_status(self, text: str) -> None:
        """Update the "what's happening right now" line without hitting the
        DB — cheap enough to call for every jittered wait / API call."""
        self.status = text
        self._live.update(_render(self._last_stats, self.friend_label, self.status))

    def refresh_sync(self) -> None:
        self._last_stats = self.storage.get_stats()
        self._live.update(_render(self._last_stats, self.friend_label, self.status))

    async def refresh(self) -> None:
        self._last_stats = await asyncio.to_thread(self.storage.get_stats)
        self._live.update(_render(self._last_stats, self.friend_label, self.status))