from __future__ import annotations

import json
from datetime import datetime, timezone

from . import db


def utc_now() -> datetime:
    return datetime.now(timezone.utc)


def serialize_datetime(value: datetime | None) -> str | None:
    if value is None:
        return None
    if value.tzinfo is None:
        value = value.replace(tzinfo=timezone.utc)
    return value.astimezone(timezone.utc).isoformat().replace("+00:00", "Z")


class RedemptionCode(db.Model):
    __tablename__ = "redemption_codes"

    id = db.Column(db.Integer, primary_key=True)
    code = db.Column(db.String(64), unique=True, nullable=False, index=True)
    status = db.Column(db.String(16), nullable=False, default="available")
    created_at = db.Column(db.DateTime, nullable=False, default=utc_now)
    used_at = db.Column(db.DateTime, nullable=True)
    used_by_username = db.Column(db.String(256), nullable=True)
    used_by_principal_name = db.Column(db.String(256), nullable=True)

    def to_dict(self):
        return {
            "id": self.id,
            "code": self.code,
            "status": self.status,
            "createdAt": serialize_datetime(self.created_at),
            "usedAt": serialize_datetime(self.used_at),
            "usedByUsername": self.used_by_username,
            "usedByPrincipalName": self.used_by_principal_name,
        }


class AuditEvent(db.Model):
    __tablename__ = "audit_events"

    id = db.Column(db.Integer, primary_key=True)
    event_type = db.Column(db.String(64), nullable=False, index=True)
    status = db.Column(db.String(16), nullable=False, default="success", index=True)
    actor = db.Column(db.String(128), nullable=False, default="system")
    code = db.Column(db.String(64), nullable=True, index=True)
    username = db.Column(db.String(256), nullable=True)
    principal_name = db.Column(db.String(256), nullable=True)
    details = db.Column(db.Text, nullable=True)
    created_at = db.Column(db.DateTime, nullable=False, default=utc_now, index=True)

    def to_dict(self):
        parsed_details = None
        if self.details:
            try:
                parsed_details = json.loads(self.details)
            except ValueError:
                parsed_details = {"raw": self.details}

        return {
            "id": self.id,
            "eventType": self.event_type,
            "status": self.status,
            "actor": self.actor,
            "code": self.code,
            "username": self.username,
            "principalName": self.principal_name,
            "details": parsed_details,
            "createdAt": serialize_datetime(self.created_at),
        }