"""Player contracts: upload, sign, download."""

import os
import uuid
from datetime import datetime

from flask import flash, redirect, render_template, request, send_file, url_for
from flask_babel import gettext as _
from flask_login import current_user, login_required
from marshmallow import ValidationError
from werkzeug.utils import secure_filename

from app.extensions import db
from app.models import Admin, Coach, Contract, Manager, Player, User
from app.permissions import can_manage_player_contract, coach_player_ids
from app.routes.users._shared import (
    ALLOWED_CONTRACT_EXTENSIONS,
    ALLOWED_SIGNED_EXTENSIONS,
    pdf_upload_error,
)
from app.routes.users.blueprint import users_bp
from app.storage import CONTRACTS_DIR, document_path
from app.validators import UploadContractSchema


def manageable_players():
    """Players the current user may attach a contract to.

    A coach used to see the squad of one team — the first row matching the
    legacy coach_id column — so a coach of two teams could file a contract
    for half of their players and no more, and a coach attached only by the
    many-to-many relationship for none at all.
    """
    if isinstance(current_user, Coach):
        player_ids = coach_player_ids(current_user)
        return (
            User.query.filter(User.id.in_(player_ids)).order_by(User.username).all()
            if player_ids
            else []
        )
    # is_active_account: a contract select that still lists people who have
    # left the club invites filing paperwork against them (SEC-16).
    return User.query.filter_by(role='player', is_active_account=True).order_by(User.username).all()


@users_bp.route('/contracts')
@login_required
def list_contracts():
    """View contracts for the current user or players they manage."""
    contracts = None
    players = None

    if isinstance(current_user, Player):
        contracts = (
            Contract.query.filter_by(
                player_id=current_user.id,
            )
            .order_by(Contract.uploaded_at.desc())
            .all()
        )
    elif isinstance(current_user, (Admin, Manager, Coach)):
        players = manageable_players()

        if players:
            player_ids = [p.id for p in players]
            contracts = (
                Contract.query.filter(
                    Contract.player_id.in_(player_ids),
                )
                .order_by(Contract.uploaded_at.desc())
                .all()
            )

    return render_template(
        'pages/contracts.html',
        contracts=contracts,
        players=players if isinstance(current_user, (Admin, Manager, Coach)) else None,
    )


@users_bp.route('/contracts/upload', methods=['GET', 'POST'])
@login_required
def upload_contract():
    """Upload a contract for a player."""
    if not isinstance(current_user, (Admin, Manager, Coach)):
        flash(_('Only presidents, managers, and coaches can upload contracts.'), 'danger')
        return redirect(url_for('users.list_contracts'))

    players = manageable_players()

    if request.method == 'POST':
        contract_schema = UploadContractSchema()
        try:
            validated = contract_schema.load(request.form)
        except ValidationError as err:
            for field, messages in err.messages.items():
                for msg in messages:
                    flash(_('%(field)s: %(msg)s', field=field, msg=msg), 'danger')
            return render_template('pages/upload_contract.html', players=players)

        player_id = validated['player_id']
        notes = validated.get('notes')

        if not can_manage_player_contract(current_user, player_id):
            flash(_('You do not have permission to upload a contract for this player.'), 'danger')
            return redirect(url_for('users.upload_contract'))

        file = request.files.get('contract_file')
        error = pdf_upload_error(file, ALLOWED_CONTRACT_EXTENSIONS)
        if error:
            flash(error, 'danger')
            return redirect(url_for('users.upload_contract'))

        player = User.query.get_or_404(player_id)
        player_teams = player.get_org_teams()
        team = player_teams[0] if player_teams else None

        original_filename = secure_filename(file.filename)
        stored_filename = f"{uuid.uuid4()}.pdf"

        # Kept relative to the document root, not absolute (see app/storage.py):
        # an absolute path pins the file to the directory the process was
        # started from, which is the one thing a release-directory deploy
        # changes.
        relative_path = os.path.join(CONTRACTS_DIR, stored_filename)
        if team:
            relative_path = os.path.join(CONTRACTS_DIR, secure_filename(team.name), stored_filename)

        absolute_path = document_path(relative_path)
        os.makedirs(os.path.dirname(absolute_path), exist_ok=True)
        file.save(absolute_path)

        contract = Contract(
            player_id=player_id,
            team_id=team.id if team else None,
            uploaded_by_id=current_user.id,
            original_filename=original_filename,
            stored_filename=stored_filename,
            file_path=relative_path,
            notes=notes if notes else None,
        )
        db.session.add(contract)
        db.session.commit()
        flash(
            _('Contract uploaded successfully for %(username)s!', username=player.username),
            'success',
        )
        return redirect(url_for('users.list_contracts'))

    return render_template('pages/upload_contract.html', players=players)


@users_bp.route('/contracts/<int:contract_id>/upload_signed', methods=['POST'])
@login_required
def upload_signed_contract(contract_id):
    """Upload a signed contract (player only)."""
    contract = Contract.query.get_or_404(contract_id)
    if not contract.can_upload_signed(current_user):
        flash(_('Only the player can upload their signed contract.'), 'danger')
        return redirect(url_for('users.list_contracts'))

    file = request.files.get('signed_file')
    error = pdf_upload_error(file, ALLOWED_SIGNED_EXTENSIONS)
    if error:
        flash(error, 'danger')
        return redirect(url_for('users.list_contracts'))

    signed_filename = f"signed_{contract.stored_filename}"
    signed_path = contract.file_path.replace(contract.stored_filename, signed_filename)
    file.save(document_path(signed_path))

    contract.signed_filename = signed_filename
    contract.signed_file_path = signed_path
    contract.status = 'signed'
    contract.signed_at = datetime.utcnow()
    db.session.commit()
    flash(_('Signed contract uploaded successfully!'), 'success')
    return redirect(url_for('users.list_contracts'))


@users_bp.route('/contracts/<int:contract_id>/download')
@login_required
def download_contract(contract_id):
    """Download a contract file."""
    contract = Contract.query.get_or_404(contract_id)
    if not contract.can_view(current_user):
        flash(_('You do not have permission to download this contract.'), 'danger')
        return redirect(url_for('users.list_contracts'))
    return send_file(
        document_path(contract.file_path),
        as_attachment=True,
        download_name=contract.original_filename,
    )


@users_bp.route('/contracts/<int:contract_id>/download_signed')
@login_required
def download_signed_contract(contract_id):
    """Download a signed contract file."""
    contract = Contract.query.get_or_404(contract_id)
    if not contract.can_view(current_user):
        flash(_('You do not have permission to download this contract.'), 'danger')
        return redirect(url_for('users.list_contracts'))
    if not contract.signed_file_path:
        flash(_('No signed contract available.'), 'danger')
        return redirect(url_for('users.list_contracts'))
    return send_file(
        document_path(contract.signed_file_path),
        as_attachment=True,
        download_name=contract.signed_filename,
    )