"""Tryout management routes for creating, viewing, and managing tryout events.

This module handles CRUD operations for tryouts and player registrations.
Uses polymorphic isinstance checks instead of role-string comparisons.
"""

from flask import Blueprint, render_template, redirect, url_for, flash, request, abort
from flask_login import login_required, current_user
from app.extensions import db
from app.models import (
    Admin, Manager, Coach, Player, Scout,
    User, Tryout, TryoutRegistration, Evaluation, Team, TeamMember,
    OrgTeam, Match, MatchParticipant,
    ESPORT_GAMES, GAME_POSITIONS,
)
from datetime import datetime

tryouts_bp = Blueprint('tryouts', __name__, url_prefix='/tryouts')


def can_manage():
    """Check if current user can manage tryouts (Admin or Manager)."""
    return isinstance(current_user, (Admin, Manager))


@tryouts_bp.route('')
@login_required
def list_tryouts():
    """List all tryouts visible to the current user.

    Delegates to the polymorphic User subclass's get_visible_tryouts() method.
    """
    tryouts = current_user.get_visible_tryouts()
    return render_template('pages/tryouts.html', tryouts=tryouts, now=datetime.utcnow())


@tryouts_bp.route('/create', methods=['GET', 'POST'])
@login_required
def create_tryout():
    """Create a new tryout event. Requires Admin or Manager."""
    if not can_manage():
        flash('You do not have permission to create tryouts.', 'danger')
        return redirect(url_for('tryouts.list_tryouts'))

    org_teams = OrgTeam.query.order_by(OrgTeam.name).all()
    managers = User.query.filter_by(role='manager', is_active_account=True).order_by(User.username).all()
    coaches = User.query.filter_by(role='coach', is_active_account=True).order_by(User.username).all()

    if request.method == 'POST':
        title = request.form.get('title')
        description = request.form.get('description')
        game = request.form.get('game')
        date_str = request.form.get('date')
        end_date_str = request.form.get('end_date')
        location = request.form.get('location')
        max_players = request.form.get('max_players')
        target_org_team_id = request.form.get('target_org_team_id')
        manager_id = request.form.get('manager_id')
        coach_ids = request.form.getlist('coach_ids')

        try:
            date_obj = datetime.strptime(date_str, '%Y-%m-%d').date()
        except (ValueError, TypeError):
            flash('Invalid start date format.', 'danger')
            return render_template('pages/tryout_form.html', tryout=None, org_teams=org_teams,
                                   managers=managers, coaches=coaches, esport_games=ESPORT_GAMES)

        end_date_obj = None
        if end_date_str:
            try:
                end_date_obj = datetime.strptime(end_date_str, '%Y-%m-%d').date()
                if end_date_obj < date_obj:
                    flash('End date cannot be before start date.', 'danger')
                    return render_template('pages/tryout_form.html', tryout=None, org_teams=org_teams,
                                           managers=managers, coaches=coaches, esport_games=ESPORT_GAMES)
            except (ValueError, TypeError):
                flash('Invalid end date format.', 'danger')
                return render_template('pages/tryout_form.html', tryout=None, org_teams=org_teams,
                                       managers=managers, coaches=coaches, esport_games=ESPORT_GAMES)

        tryout = Tryout(
            title=title, description=description, game=game, date=date_obj,
            end_date=end_date_obj,
            location=location,
            max_players=int(max_players) if max_players else None,
            created_by=current_user.id, status='upcoming',
            target_org_team_id=int(target_org_team_id) if target_org_team_id else None,
            manager_id=int(manager_id) if manager_id else None,
        )
        db.session.add(tryout)
        db.session.flush()

        # Assign coaches via many-to-many
        if coach_ids:
            coach_users = User.query.filter(User.id.in_([int(c) for c in coach_ids])).all()
            tryout.coaches = coach_users

        db.session.commit()
        flash('Tryout created successfully!', 'success')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout.id))

    return render_template('pages/tryout_form.html', tryout=None, org_teams=org_teams,
                           managers=managers, coaches=coaches, esport_games=ESPORT_GAMES)


@tryouts_bp.route('/<int:tryout_id>/edit', methods=['GET', 'POST'])
@login_required
def edit_tryout(tryout_id):
    """Edit an existing tryout event. Permission based on can_manage_this_tryout."""
    tryout = Tryout.query.get_or_404(tryout_id)

    if not current_user.can_manage_this_tryout(tryout):
        flash('You do not have permission to edit this tryout.', 'danger')
        return redirect(url_for('tryouts.list_tryouts'))

    if tryout.is_ended:
        flash('This tryout has ended and can no longer be modified.', 'danger')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout.id))

    org_teams = OrgTeam.query.order_by(OrgTeam.name).all()
    managers = User.query.filter_by(role='manager', is_active_account=True).order_by(User.full_name).all()
    coaches = User.query.filter_by(role='coach', is_active_account=True).order_by(User.full_name).all()

    if request.method == 'POST':
        title = request.form.get('title')
        description = request.form.get('description')
        game = request.form.get('game')
        date_str = request.form.get('date')
        end_date_str = request.form.get('end_date')
        location = request.form.get('location')
        max_players = request.form.get('max_players')
        target_org_team_id = request.form.get('target_org_team_id')
        manager_id = request.form.get('manager_id')
        coach_ids = request.form.getlist('coach_ids')

        try:
            date_obj = datetime.strptime(date_str, '%Y-%m-%d').date()
        except (ValueError, TypeError):
            flash('Invalid start date format.', 'danger')
            return render_template('pages/tryout_form.html', tryout=tryout, org_teams=org_teams,
                                   managers=managers, coaches=coaches, esport_games=ESPORT_GAMES)

        end_date_obj = None
        if end_date_str:
            try:
                end_date_obj = datetime.strptime(end_date_str, '%Y-%m-%d').date()
                if end_date_obj < date_obj:
                    flash('End date cannot be before start date.', 'danger')
                    return render_template('pages/tryout_form.html', tryout=tryout, org_teams=org_teams,
                                           managers=managers, coaches=coaches, esport_games=ESPORT_GAMES)
            except (ValueError, TypeError):
                flash('Invalid end date format.', 'danger')
                return render_template('pages/tryout_form.html', tryout=tryout, org_teams=org_teams,
                                       managers=managers, coaches=coaches, esport_games=ESPORT_GAMES)

        tryout.title = title
        tryout.description = description
        tryout.game = game
        tryout.date = date_obj
        tryout.end_date = end_date_obj
        tryout.location = location
        tryout.max_players = int(max_players) if max_players else None
        tryout.target_org_team_id = int(target_org_team_id) if target_org_team_id else None
        tryout.manager_id = int(manager_id) if manager_id else None

        # Update coaches via many-to-many
        if coach_ids:
            coach_users = User.query.filter(User.id.in_([int(c) for c in coach_ids])).all()
            tryout.coaches = coach_users
        else:
            tryout.coaches = []

        db.session.commit()
        flash('Tryout updated successfully!', 'success')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout.id))

    return render_template('pages/tryout_form.html', tryout=tryout, org_teams=org_teams,
                           managers=managers, coaches=coaches, esport_games=ESPORT_GAMES)


@tryouts_bp.route('/<int:tryout_id>')
@login_required
def view_tryout(tryout_id):
    """View a specific tryout with all details. Permission via polymorphic dispatch."""
    tryout = Tryout.query.get_or_404(tryout_id)

    can_view = False
    if isinstance(current_user, Admin):
        can_view = True
    elif isinstance(current_user, Manager):
        can_view = tryout.created_by == current_user.id or tryout.manager_id == current_user.id
    elif isinstance(current_user, Coach):
        can_view = current_user.can_manage_this_tryout(tryout)
    elif isinstance(current_user, Player):
        is_registered = TryoutRegistration.query.filter_by(
            tryout_id=tryout_id, player_id=current_user.id).first() is not None
        player_in_match = MatchParticipant.query.join(Match).filter(
            MatchParticipant.player_id == current_user.id,
            Match.tryout_id == tryout_id,
        ).first() is not None
        can_view = is_registered or player_in_match
    elif isinstance(current_user, Scout):
        can_view = True

    if not can_view:
        flash('You do not have permission to view this tryout.', 'danger')
        return redirect(url_for('tryouts.list_tryouts'))

    registrations = TryoutRegistration.query.filter_by(tryout_id=tryout_id).all()
    registered_players = [User.query.get(r.player_id) for r in registrations if r.player_id]
    evaluations = Evaluation.query.filter_by(tryout_id=tryout_id).all()

    player_eval_status = {}
    if current_user.can_evaluate():
        for p in registered_players:
            existing = Evaluation.query.filter_by(
                tryout_id=tryout_id, player_id=p.id, evaluator_id=current_user.id,
            ).first()
            player_eval_status[p.id] = existing is not None

    is_registered = TryoutRegistration.query.filter_by(
        tryout_id=tryout_id, player_id=current_user.id,
    ).first() is not None

    teams = Team.query.filter_by(tryout_id=tryout_id).all()
    team_data = []
    for team in teams:
        members = TeamMember.query.filter_by(team_id=team.id).all()
        team_data.append({
            'team': team,
            'members': [{'player': User.query.get(m.player_id), 'position': m.position}
                        for m in members],
        })

    can_edit = current_user.can_manage_this_tryout(tryout)

    can_view_calendar = can_edit
    if isinstance(current_user, Player):
        player_in_match = MatchParticipant.query.join(Match).filter(
            MatchParticipant.player_id == current_user.id,
            Match.tryout_id == tryout_id,
        ).first() is not None
        can_view_calendar = is_registered or player_in_match

    all_players = None
    if can_edit:
        all_players = User.query.filter_by(role='player').order_by(User.username).all()

    matches = Match.query.filter_by(tryout_id=tryout_id).order_by(Match.date, Match.start_time).all()
    match_data = []
    for match in matches:
        all_participants = list(match.participants.all())
        confirmed_count = sum(1 for p in all_participants if p.attendance_confirmed)
        total_count = len(all_participants)

        player_presence = []
        for p in all_participants:
            if p.player:
                player_presence.append({
                    'participant_id': p.id, 'player_id': p.player_id,
                    'player_name': p.player.username,
                    'attendance_confirmed': p.attendance_confirmed,
                })

        if match.match_type == 'team_vs_team':
            participants = {
                'team1': match.team1.name if match.team1 else 'TBD',
                'team2': match.team2.name if match.team2 else 'TBD',
                'team1_players': [{'name': m.player.username, 'position': m.position}
                                  for m in match.team1.members.all()] if match.team1 else [],
                'team2_players': [{'name': m.player.username, 'position': m.position}
                                  for m in match.team2.members.all()] if match.team2 else [],
            }
        elif match.match_type == 'player_vs_player':
            team1_players = [{'name': p.player.username, 'position': p.position}
                             for p in match.participants.filter_by(team_side=1).all() if p.player]
            team2_players = [{'name': p.player.username, 'position': p.position}
                             for p in match.participants.filter_by(team_side=2).all() if p.player]
            participants = {
                'team1': 'Team 1', 'team2': 'Team 2',
                'team1_players': team1_players, 'team2_players': team2_players,
            }
        else:
            participants = [p.player.username for p in match.participants.all()]

        match_data.append({
            'match': match, 'participants': participants,
            'confirmed_count': confirmed_count, 'total_count': total_count,
            'player_presence': player_presence,
        })

    return render_template('pages/view_tryout.html',
                           tryout=tryout, registered_players=registered_players,
                           evaluations=evaluations, player_eval_status=player_eval_status,
                           is_registered=is_registered, registrations=registrations,
                           team_data=team_data, can_edit=can_edit,
                           can_view_calendar=can_view_calendar, all_players=all_players,
                           matches=matches, match_data=match_data,
                           game_positions=GAME_POSITIONS, now=datetime.utcnow())


@tryouts_bp.route('/<int:tryout_id>/register', methods=['POST'])
@login_required
def register_for_tryout(tryout_id):
    """Register a player for a tryout. Only Players can self-register."""
    tryout = Tryout.query.get_or_404(tryout_id)
    if not isinstance(current_user, Player):
        flash('Only players can register for tryouts.', 'danger')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    if tryout.status not in ['upcoming', 'in_progress']:
        flash('This tryout is not accepting registrations.', 'danger')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    existing = TryoutRegistration.query.filter_by(
        tryout_id=tryout_id, player_id=current_user.id).first()
    if existing:
        flash('You are already registered for this tryout.', 'info')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    if tryout.max_players:
        count = TryoutRegistration.query.filter_by(tryout_id=tryout_id).count()
        if count >= tryout.max_players:
            flash('This tryout is full.', 'danger')
            return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    registration = TryoutRegistration(tryout_id=tryout_id, player_id=current_user.id)
    db.session.add(registration)
    db.session.commit()
    flash('Successfully registered for tryout!', 'success')
    return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))


@tryouts_bp.route('/<int:tryout_id>/status', methods=['POST'])
@login_required
def update_status(tryout_id):
    """Update the status of a tryout."""
    tryout = Tryout.query.get_or_404(tryout_id)
    if not current_user.can_manage_this_tryout(tryout):
        flash('Permission denied.', 'danger')
        return redirect(url_for('tryouts.list_tryouts'))
    new_status = request.form.get('status')
    if new_status in ['upcoming', 'in_progress', 'completed']:
        tryout.status = new_status
        db.session.commit()
        flash(f'Tryout status updated to {new_status}.', 'success')
    return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))


@tryouts_bp.route('/<int:tryout_id>/registration/<int:player_id>/status', methods=['POST'])
@login_required
def update_registration_status(tryout_id, player_id):
    """Update a registration's attendance status."""
    tryout = Tryout.query.get_or_404(tryout_id)
    if not current_user.can_manage_this_tryout(tryout):
        flash('Permission denied.', 'danger')
        return redirect(url_for('tryouts.list_tryouts'))

    registration = TryoutRegistration.query.filter_by(
        tryout_id=tryout_id, player_id=player_id).first_or_404()
    new_status = request.form.get('status')
    if new_status in ['registered', 'attended', 'no_show']:
        registration.status = new_status
        db.session.commit()
        flash('Registration status updated.', 'success')
    return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))


@tryouts_bp.route('/<int:tryout_id>/register_player', methods=['POST'])
@login_required
def register_player(tryout_id):
    """Manually register a player for a tryout (by managers/coaches)."""
    tryout = Tryout.query.get_or_404(tryout_id)
    if not current_user.can_manage_this_tryout(tryout):
        flash('Permission denied.', 'danger')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))
    player_id = request.form.get('player_id')
    if not player_id:
        flash('Please select a player.', 'danger')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    player = User.query.get_or_404(int(player_id))
    if not isinstance(player, Player):
        flash('Can only register players.', 'danger')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    existing = TryoutRegistration.query.filter_by(
        tryout_id=tryout_id, player_id=player.id).first()
    if existing:
        flash(f'{player.username} is already registered for this tryout.', 'info')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    if tryout.max_players:
        count = TryoutRegistration.query.filter_by(tryout_id=tryout_id).count()
        if count >= tryout.max_players:
            flash('This tryout is full.', 'danger')
            return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    registration = TryoutRegistration(tryout_id=tryout_id, player_id=player.id)
    db.session.add(registration)
    db.session.commit()
    flash(f'{player.username} registered for tryout!', 'success')
    return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))


@tryouts_bp.route('/<int:tryout_id>/remove_player/<int:player_id>', methods=['POST'])
@login_required
def remove_player(tryout_id, player_id):
    """Remove a registered player from a tryout (cascades to teams/matches)."""
    tryout = Tryout.query.get_or_404(tryout_id)
    if not current_user.can_manage_this_tryout(tryout):
        flash('Permission denied.', 'danger')
        return redirect(url_for('tryouts.list_tryouts'))

    player = User.query.get_or_404(player_id)

    registration = TryoutRegistration.query.filter_by(
        tryout_id=tryout_id, player_id=player_id).first()
    if registration:
        db.session.delete(registration)

    team_ids = [t.id for t in Team.query.filter_by(tryout_id=tryout_id).all()]
    if team_ids:
        TeamMember.query.filter(
            TeamMember.team_id.in_(team_ids),
            TeamMember.player_id == player_id,
        ).delete(synchronize_session=False)

    match_ids = [m.id for m in Match.query.filter_by(tryout_id=tryout_id).all()]
    if match_ids:
        MatchParticipant.query.filter(
            MatchParticipant.match_id.in_(match_ids),
            MatchParticipant.player_id == player_id,
        ).delete(synchronize_session=False)

    db.session.commit()
    flash(f'{player.username} removed from tryout.', 'success')
    return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))


@tryouts_bp.route('/<int:tryout_id>/team/create', methods=['POST'])
@login_required
def create_team(tryout_id):
    """Create a tryout-specific team."""
    tryout = Tryout.query.get_or_404(tryout_id)
    if not current_user.can_manage_this_tryout(tryout):
        flash('Permission denied.', 'danger')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    team_name = request.form.get('team_name')
    if team_name:
        team = Team(tryout_id=tryout_id, name=team_name, created_by=current_user.id)
        db.session.add(team)
        db.session.commit()
        flash(f'Team "{team_name}" created!', 'success')
    return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))


@tryouts_bp.route('/<int:tryout_id>/team/<int:team_id>/add', methods=['POST'])
@login_required
def add_to_team(tryout_id, team_id):
    """Add a player to a tryout team."""
    team = Team.query.get_or_404(team_id)
    tryout = Tryout.query.get_or_404(tryout_id)
    if not current_user.can_manage_this_tryout(tryout):
        flash('Permission denied.', 'danger')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    # The two ids arrive independently in the URL. Without this check, being
    # allowed to manage tryout A was enough to modify a team belonging to
    # tryout B, since only the tryout was authorised.
    if team.tryout_id != tryout_id:
        abort(404)

    player_id = request.form.get('player_id', type=int)
    if not player_id:
        flash('Please select a player.', 'danger')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    # Only players registered for this tryout may be placed on its teams.
    is_registered = TryoutRegistration.query.filter_by(
        tryout_id=tryout_id, player_id=player_id).first() is not None
    if not is_registered:
        flash('That player is not registered for this tryout.', 'danger')
        return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))

    position = request.form.get('position', '')
    existing = TeamMember.query.filter_by(team_id=team_id, player_id=player_id).first()
    if existing:
        flash('Player is already on this team.', 'info')
    else:
        member = TeamMember(team_id=team_id, player_id=player_id, position=position)
        db.session.add(member)
        db.session.commit()
        flash('Player added to team!', 'success')
    return redirect(url_for('tryouts.view_tryout', tryout_id=tryout_id))


@tryouts_bp.route('/<int:tryout_id>/delete', methods=['POST'])
@login_required
def delete_tryout(tryout_id):
    """Delete a tryout and all associated data (matches, teams, registrations, evaluations)."""
    tryout = Tryout.query.get_or_404(tryout_id)
    if not current_user.can_manage_this_tryout(tryout):
        flash('You do not have permission to delete this tryout.', 'danger')
        return redirect(url_for('tryouts.list_tryouts'))

    # Delete match participants for all matches in this tryout
    match_ids = [m.id for m in Match.query.filter_by(tryout_id=tryout_id).all()]
    if match_ids:
        MatchParticipant.query.filter(
            MatchParticipant.match_id.in_(match_ids)
        ).delete(synchronize_session=False)
        # Delete matches
        Match.query.filter(Match.id.in_(match_ids)).delete(synchronize_session=False)

    # Delete team members for all teams in this tryout
    team_ids = [t.id for t in Team.query.filter_by(tryout_id=tryout_id).all()]
    if team_ids:
        TeamMember.query.filter(
            TeamMember.team_id.in_(team_ids)
        ).delete(synchronize_session=False)
        # Delete teams
        Team.query.filter(Team.id.in_(team_ids)).delete(synchronize_session=False)

    # Delete registrations
    TryoutRegistration.query.filter_by(tryout_id=tryout_id).delete()

    # Delete evaluations
    Evaluation.query.filter_by(tryout_id=tryout_id).delete()

    db.session.delete(tryout)
    db.session.commit()
    flash('Tryout deleted successfully.', 'success')
    return redirect(url_for('tryouts.list_tryouts'))