import smtplib
import subprocess
import json
import os
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from datetime import date, timedelta
import calendar as cal_module
from bills import load_bills
from settings import get_setting


def _gmail():
    """Resolve Gmail creds + recipient from Settings (env-var fallback)."""
    email = get_setting("gmail_address", env="GMAIL_ADDRESS", default="")
    pw = get_setting("gmail_app_password", env="GMAIL_APP_PASSWORD", default="")
    recipient = get_setting("reminder_recipient", default="") or email
    return email, pw, recipient


def send_email(subject, body_html, body_text):
    email, pw, recipient = _gmail()
    if not (email and pw):
        print("Gmail not configured in Settings — skipping email reminder.")
        return
    msg = MIMEMultipart("alternative")
    msg["Subject"] = subject
    msg["From"] = f"Moon Household Budget <{email}>"
    msg["To"] = recipient
    msg.attach(MIMEText(body_text, "plain"))
    msg.attach(MIMEText(body_html, "html"))
    with smtplib.SMTP_SSL("smtp.gmail.com", 465) as server:
        server.login(email, pw)
        server.sendmail(email, recipient, msg.as_string())


def mac_notification(title, message):
    # macOS-only; no-op (don't crash) when osascript isn't available, e.g. in
    # the Linux container.
    script = f'display notification "{message}" with title "{title}" sound name "Default"'
    try:
        subprocess.run(["osascript", "-e", script], check=False)
    except (FileNotFoundError, OSError):
        pass


def bills_due_in(days):
    today = date.today()
    target = today + timedelta(days=days)
    all_bills = load_bills()
    due = []
    for b in all_bills:
        if not b.get("active", True):
            continue
        if b.get("autopay", False):
            continue
        if not b.get("remind", True):
            continue
        due_day = b.get("due_day")
        if not due_day:
            continue
        _, num_days = cal_module.monthrange(target.year, target.month)
        due_day_clamped = min(due_day, num_days)
        bill_date = date(target.year, target.month, due_day_clamped)
        if bill_date == target:
            due.append({**b, "due_date": bill_date})
    return due


def check_and_send_reminders():
    sent = []

    for days_ahead, label in [(3, "in 3 days"), (0, "TODAY")]:
        due = bills_due_in(days_ahead)
        if not due:
            continue

        total = sum(b.get("amount", 0) for b in due if b.get("amount"))

        # Mac notifications — one per bill
        for b in due:
            amt = f"${b['amount']:.2f}" if b.get("amount") else "amount varies"
            mac_notification(
                f"Bill Due {label.title()}",
                f"{b['name']} — {amt}"
            )

        # Email — one digest
        subject = f"🌙 Moon Budget: {len(due)} bill{'s' if len(due) != 1 else ''} due {label}"

        rows = ""
        for b in due:
            amt = f"${b['amount']:.2f}" if b.get("amount") else "—"
            cat = b.get("category", "")
            rows += f"""
            <tr>
              <td style="padding:8px 12px;border-bottom:1px solid #EDE8E2;">{b['name']}</td>
              <td style="padding:8px 12px;border-bottom:1px solid #EDE8E2;font-weight:600;">{amt}</td>
              <td style="padding:8px 12px;border-bottom:1px solid #EDE8E2;color:#7A6E68;">{cat}</td>
            </tr>"""

        total_row = f"${total:.2f}" if total else ""

        body_html = f"""
        <div style="font-family:'Helvetica Neue',Arial,sans-serif;max-width:520px;margin:0 auto;background:#FAF7F2;padding:24px;border-radius:12px;">
          <h2 style="font-size:22px;color:#3A3330;margin-bottom:4px;">🌙 Moon Household Budget</h2>
          <p style="color:#7A6E68;margin-bottom:20px;font-size:14px;">Bill reminder — due <strong>{label}</strong></p>
          <table style="width:100%;border-collapse:collapse;background:#fff;border-radius:8px;overflow:hidden;box-shadow:0 2px 8px rgba(80,60,50,0.08);">
            <thead>
              <tr style="background:#F5F1EC;">
                <th style="text-align:left;padding:8px 12px;font-size:11px;text-transform:uppercase;letter-spacing:0.07em;color:#B0A89E;">Bill</th>
                <th style="text-align:left;padding:8px 12px;font-size:11px;text-transform:uppercase;letter-spacing:0.07em;color:#B0A89E;">Amount</th>
                <th style="text-align:left;padding:8px 12px;font-size:11px;text-transform:uppercase;letter-spacing:0.07em;color:#B0A89E;">Category</th>
              </tr>
            </thead>
            <tbody>{rows}</tbody>
            {f'<tfoot><tr><td style="padding:8px 12px;font-weight:700;" colspan="2">Total: {total_row}</td><td></td></tr></tfoot>' if total_row else ''}
          </table>
          <p style="color:#B0A89E;font-size:12px;margin-top:20px;text-align:center;">Moon Household Budget · sent to bonna61@gmail.com</p>
        </div>"""

        body_text = f"Moon Budget — Bills due {label}:\n\n"
        for b in due:
            amt = f"${b['amount']:.2f}" if b.get("amount") else "varies"
            body_text += f"  • {b['name']} — {amt}\n"
        if total:
            body_text += f"\nTotal: ${total:.2f}\n"

        send_email(subject, body_html, body_text)
        sent.append(f"{len(due)} bills due {label}")

    return sent


if __name__ == "__main__":
    results = check_and_send_reminders()
    if results:
        print("Sent reminders:", ", ".join(results))
    else:
        print("No reminders to send today.")