"""
app/models/notification_recipient.py
------------------------------------
Per-contract additional notification recipients.

Each row is ONE extra recipient attached to a Contract (Project) who should be
notified when selected notification events fire within that contract's
facilities — in ADDITION to whoever the global NotificationMatrix already
routes to.

A recipient is either:
  - an existing app user  (user_id set, email NULL)  → in-app notification + email
  - a free-form email      (email set, user_id NULL)  → email only

`event_types` is a JSON list of event_type keys (matching MATRIX_EVENTS) that
this recipient subscribes to for this contract.  A recipient is notified only
when the firing event_type is present in this list.  An empty list means the
recipient receives nothing (the add form requires at least one event).

Resolution happens centrally in notify_by_matrix() (app/utils/notifications.py),
which derives the contract from the event's facility / issue / inspection.
"""

import json
from app import db
from app.utils.time_utils import now_eastern


class ContractNotificationRecipient(db.Model):
    __tablename__ = 'contract_notification_recipients'

    id          = db.Column(db.Integer, primary_key=True)
    project_id  = db.Column(
        db.Integer,
        db.ForeignKey('projects.id', ondelete='CASCADE'),
        nullable=False, index=True,
    )
    # Exactly one of user_id / email is set (enforced in the route, not the DB).
    user_id     = db.Column(
        db.Integer,
        db.ForeignKey('users.id', ondelete='CASCADE'),
        nullable=True, index=True,
    )
    email       = db.Column(db.String(200), nullable=True)
    # JSON list of event_type keys this recipient is subscribed to for this contract.
    event_types = db.Column(db.Text, nullable=True)   # JSON-encoded list[str]
    created_at  = db.Column(db.DateTime, nullable=False, default=now_eastern)

    project = db.relationship('Project', foreign_keys=[project_id],
                              backref=db.backref('notification_recipients',
                                                 lazy='dynamic',
                                                 cascade='all, delete-orphan'))
    user    = db.relationship('User', foreign_keys=[user_id])

    def get_event_types(self) -> list:
        """Return event_types as a Python list of strings."""
        if not self.event_types:
            return []
        try:
            result = json.loads(self.event_types)
            return [e for e in result if isinstance(e, str) and e.strip()]
        except (json.JSONDecodeError, TypeError):
            return []

    def set_event_types(self, values) -> None:
        """Store a list of event_type keys as a JSON string."""
        clean = [v.strip() for v in (values or []) if isinstance(v, str) and v.strip()]
        self.event_types = json.dumps(clean)

    @property
    def display_target(self) -> str:
        """Human-readable recipient label for the UI."""
        if self.user_id and self.user:
            return f'{self.user.display_name} ({self.user.email})'
        return self.email or '—'

    def __repr__(self):
        who = f'user={self.user_id}' if self.user_id else f'email={self.email}'
        return f'<ContractNotificationRecipient project={self.project_id} {who}>'