"""
Registry Tab — displays loaded plugins and their status.

Subscribes to registry.plugin.* events to show live plugin state.
Allows loading/unloading plugins interactively.
"""

from __future__ import annotations

from typing import Any, Optional

from textual.app import ComposeResult
from textual.binding import Binding
from textual.widget import Widget
from textual.widgets import DataTable, Footer, Label, Static


class RegistryTab(Widget):
    """
    Plugin registry viewer.

    Shows all discovered plugins with their version, status, module path,
    and load timestamp.  Pressing Enter on a row toggles load/unload.
    """

    DEFAULT_CSS = """
    RegistryTab {
        layout: vertical;
        height: 1fr;
        padding: 1 2;
    }
    RegistryTab .tab-title {
        color: $primary;
        text-style: bold;
        height: 1;
        margin-bottom: 1;
    }
    RegistryTab DataTable {
        height: 1fr;
        border: round $primary;
    }
    RegistryTab .hint {
        height: 1;
        color: $text-muted;
        margin-top: 1;
    }
    """

    BINDINGS = [
        Binding("r", "refresh_registry", "Refresh"),
        Binding("enter", "toggle_plugin", "Toggle"),
    ]

    COLUMNS = [
        ("Name", 14),
        ("Version", 9),
        ("Status", 11),
        ("Tags", 22),
        ("Loaded At", 22),
        ("Module", 32),
        ("Error", 30),
    ]

    def compose(self) -> ComposeResult:
        yield Static("//  REGISTRY  —  Plugin Manifest", classes="tab-title")
        yield DataTable(id="registry-table", zebra_stripes=True, cursor_type="row")
        yield Static(
            "Press [bold]r[/bold] to refresh  |  [bold]Enter[/bold] to toggle load",
            classes="hint",
        )

    def on_mount(self) -> None:
        table = self.query_one("#registry-table", DataTable)
        for col_label, width in self.COLUMNS:
            table.add_column(col_label, width=width)

        app = self.app
        if hasattr(app, "bus"):
            app.bus.subscribe("registry.plugin.*", self._on_registry_event)
        self._refresh_table()

    def _on_registry_event(self, topic: str, data: Any) -> None:
        self.call_from_thread(self._refresh_table)

    def _refresh_table(self) -> None:
        table = self.query_one("#registry-table", DataTable)
        table.clear()
        app = self.app
        if not hasattr(app, "registry"):
            return
        for record in sorted(app.registry.all_records(), key=lambda r: r.name):
            loaded_at = record.loaded_at.strftime("%Y-%m-%d %H:%M:%S") if record.loaded_at else "—"
            table.add_row(
                record.name,
                record.version,
                record.status.name,
                ", ".join(record.tags) or "—",
                loaded_at,
                record.module_path,
                record.error or "—",
            )

    def action_refresh_registry(self) -> None:
        self._refresh_table()

    def action_toggle_plugin(self) -> None:
        table = self.query_one("#registry-table", DataTable)
        row_key = table.cursor_row
        if row_key is None:
            return
        # Get plugin name from the focused row
        try:
            cell_value = table.get_cell_at((row_key, 0))
        except Exception:
            return
        plugin_name = str(cell_value)
        app = self.app
        if not hasattr(app, "registry"):
            return
        record = app.registry.get(plugin_name)
        if record is None:
            return
        from core.registry import PluginStatus
        if record.status == PluginStatus.ACTIVE:
            app.registry.unload(plugin_name)
        else:
            app.registry.load(plugin_name)
        self._refresh_table()