#    Copyright (C) 2025 James Brotosky, Brandon Wickline
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU Affero General Public License as published
#    by the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU Affero General Public License for more details.
#
#    You should have received a copy of the GNU Affero General Public License
#    along with this program.  If not, see <https://www.gnu.org/licenses/>.

"""
Policy Selector Screen Module

Provides a Textual Screen wrapper for the PolicySelector widget that manages
the policy selection workflow.
"""

import logging

from textual.app import ComposeResult
from textual.screen import Screen

from widgets.policyselector import PolicySelector

logger = logging.getLogger(__name__)


class PolicySelectorScreen(Screen):
    """
    A Textual Screen for policy selection in agent move operations.

    This screen wraps the PolicySelector widget and manages the workflow
    of selecting a target policy for bulk agent movements.

    Attributes:
        policies: List of available policies (Policy objects or DataFrame).
        agent_move_operations: Reference to the parent AgentMoveOperations widget.
    """

    CSS = """
    Screen {
        layout: vertical;
        background: $surface;
    }
    """

    def __init__(
        self,
        policies,
        agent_move_operations=None,
    ):
        """
        Initialize the PolicySelectorScreen.

        Args:
            policies: List of available policies to display.
            agent_move_operations: Reference to parent AgentMoveOperations widget.
                Used to call back when policy selection is confirmed.
        """
        super().__init__()
        self.policies = policies
        self.agent_move_operations = agent_move_operations

    def compose(self) -> ComposeResult:
        """Create the PolicySelector widget."""
        yield PolicySelector(self.policies)

    def on_policy_selector_policy_selected(
        self, message: PolicySelector.PolicySelected
    ) -> None:
        """
        Handle policy selection from the PolicySelector widget.

        When a policy is selected, this handler:
        1. Closes the selector screen
        2. Calls the parent AgentMoveOperations to execute the move

        Args:
            message (PolicySelector.PolicySelected): Contains the selected policy.
        """
        # Pop this screen to return to AgentMoveOperations
        self.app.pop_screen()

        # Call parent widget's method to execute the move
        if self.agent_move_operations:
            self.agent_move_operations._execute_move_to_policy(message.policy)