import asyncio
from datetime import datetime, timedelta, timezone

from fastapi import HTTPException
from jinja2 import Environment, FileSystemLoader, select_autoescape

from cbh.api.calls.models import CallModel
from cbh.api.calls.dto import CallStatus
from cbh.core.config import settings


def can_edit_call(call: CallModel) -> None:
    """
    Check if the call can be edited.
    """
    now = datetime.now(timezone.utc) if call.event.startDate.tzinfo else datetime.now()
    min_edit_time = now + timedelta(hours=48)

    if call.status != CallStatus.SCHEDULED or call.event.startDate < min_edit_time:
        raise HTTPException(status_code=400, detail="Call cannot be edited.")


def calculate_sleep_time(call: CallModel) -> int:
    """
    Calculate the sleep time for the reminder.
    """
    now = datetime.now(timezone.utc) if call.event.startDate.tzinfo else datetime.now()
    reminder_time = call.event.startDate - timedelta(hours=1)
    sleep_time = (reminder_time - now).total_seconds()

    return max(0, int(sleep_time))


async def send_customer_booking_email(call: CallModel) -> None:
    """
    Send a booking email.
    """
    if not call.event.isActive:
        return
    templates_path = settings.BASE_DIR / "cbh" / "templates" / "emails"
    env = Environment(
        loader=FileSystemLoader(templates_path),
        autoescape=select_autoescape(["html", "xml"]),
    )
    template = env.get_template("bookingConfirmation.html")

    template_content = template.render(
        coach_name=call.coach.name,
        user_name=call.customer.name,
        start_date=call.event.startDate.strftime("%d %B %Y, %H:%M"),
        join_link=f"{settings.Audience}/calls/{call.id}",
        duration=(call.event.endDate - call.event.startDate).total_seconds() // 60,
    )

    await settings.EMAIL_CLIENT.send_email(
        call.customer.email,
        f"You're all set! Session with {call.coach.name} confirmed!",
        template_content,
    )


async def send_coach_booking_email(call: CallModel) -> None:
    """
    Send a booking email.
    """
    if not call.event.isActive:
        return
    templates_path = settings.BASE_DIR / "cbh" / "templates" / "emails"
    env = Environment(
        loader=FileSystemLoader(templates_path),
        autoescape=select_autoescape(["html", "xml"]),
    )
    template = env.get_template("bookingConfirmationCoach.html")
    template_content = template.render(
        coach_name=call.coach.name,
        user_name=call.customer.name,
        start_date=call.event.startDate.strftime("%d %B %Y, %H:%M"),
        join_link=f"{settings.Audience}/calls/{call.id}",
        duration=(call.event.endDate - call.event.startDate).total_seconds() // 60,
    )

    await settings.EMAIL_CLIENT.send_email(
        call.coach.email,
        f"New session booked with {call.customer.name}!",
        template_content,
    )


async def send_cancel_customer_email(call: CallModel) -> None:
    """
    Send a cancellation email.
    """
    templates_path = settings.BASE_DIR / "cbh" / "templates" / "emails"
    env = Environment(
        loader=FileSystemLoader(templates_path),
        autoescape=select_autoescape(["html", "xml"]),
    )
    template = env.get_template("sessionCancellation.html")
    template_content = template.render(
        coach_name=call.coach.name,
        user_name=call.customer.name,
        start_date=call.event.startDate.strftime("%d %B %Y, %H:%M"),
        duration=(call.event.endDate - call.event.startDate).total_seconds() // 60,
    )

    await settings.EMAIL_CLIENT.send_email(
        call.customer.email,
        f"Your session with {call.coach.name} has been cancelled.",
        template_content,
    )


async def send_cancel_coach_email(call: CallModel) -> None:
    """
    Send a cancellation email.
    """
    templates_path = settings.BASE_DIR / "cbh" / "templates" / "emails"
    env = Environment(
        loader=FileSystemLoader(templates_path),
        autoescape=select_autoescape(["html", "xml"]),
    )
    template = env.get_template("sessionCancellationCoach.html")
    template_content = template.render(
        coach_name=call.coach.name,
        user_name=call.customer.name,
        start_date=call.event.startDate.strftime("%d %B %Y, %H:%M"),
        duration=(call.event.endDate - call.event.startDate).total_seconds() // 60,
    )

    await settings.EMAIL_CLIENT.send_email(
        call.coach.email,
        f"{call.customer.name} cancelled their session.",
        template_content,
    )


async def send_session_reminder_email(call: CallModel) -> None:
    """
    Send a session reminder email.
    """
    if not call.event.isActive:
        return
    sleep_time = calculate_sleep_time(call)
    await asyncio.sleep(sleep_time)

    templates_path = settings.BASE_DIR / "cbh" / "templates" / "emails"
    env = Environment(
        loader=FileSystemLoader(templates_path),
        autoescape=select_autoescape(["html", "xml"]),
    )
    template = env.get_template("sessionReminder.html")
    template_content = template.render(
        coach_name=call.coach.name,
        user_name=call.customer.name,
        start_date=call.event.startDate.strftime("%d %B %Y, %H:%M"),
        join_link=f"{settings.Audience}/calls/{call.id}",
        duration=(call.event.endDate - call.event.startDate).total_seconds() // 60,
    )

    await settings.EMAIL_CLIENT.send_email(
        call.customer.email,
        f"Your session with {call.coach.name} is starting in 1 hour.",
        template_content,
    )


async def send_session_reminder_coach_email(call: CallModel) -> None:
    """
    Send a session reminder email.
    """
    if not call.event.isActive:
        return
    sleep_time = calculate_sleep_time(call)
    await asyncio.sleep(sleep_time)

    templates_path = settings.BASE_DIR / "cbh" / "templates" / "emails"
    env = Environment(
        loader=FileSystemLoader(templates_path),
        autoescape=select_autoescape(["html", "xml"]),
    )
    template = env.get_template("sessionReminderCoach.html")
    template_content = template.render(
        coach_name=call.coach.name,
        user_name=call.customer.name,
        start_date=call.event.startDate.strftime("%d %B %Y, %H:%M"),
        join_link=f"{settings.Audience}/calls/{call.id}",
        duration=(call.event.endDate - call.event.startDate).total_seconds() // 60,
    )

    await settings.EMAIL_CLIENT.send_email(
        call.coach.email,
        f"Your session with {call.customer.name} is starting in 1 hour.",
        template_content,
    )


async def send_anonymous_booking_email(call: CallModel) -> None:
    """
    Send a anonymous booking email.
    """
    templates_path = settings.BASE_DIR / "cbh" / "templates" / "emails"
    env = Environment(
        loader=FileSystemLoader(templates_path),
        autoescape=select_autoescape(["html", "xml"]),
    )
    template = env.get_template("anonymousBookingConfirmation.html")
    template_content = template.render(
        coach_name=call.coach.name,
        start_date=call.event.startDate.strftime("%d %B %Y, %H:%M"),
        join_link=f"{settings.Audience}/calls/{call.id}",
        duration=(call.event.endDate - call.event.startDate).total_seconds() // 60,
        registration_link=f"{settings.Audience}/signup/complete?accountId={call.customer.id}",
    )

    await settings.EMAIL_CLIENT.send_email(
        call.customer.email,
        f"You're all set! Session with {call.coach.name} confirmed!",
        template_content,
    )