#!/usr/bin/env python3
# mailer.py — Mock e-mail sender for dev/demo (R6 #3)
# v1.0 dradulic@outlook.com / damir@rinet.one — 2026-05-04
"""
In dev/demo mode, e-mails are appended to:
  - /tmp/pgz_mailbox/<unix-ts>-<recipient>.eml          (raw .eml file)
  - /tmp/pgz_mailbox/INDEX.jsonl                         (one JSON line per send)
plus printed to stdout (visible in journalctl).

Set PGZ_SMTP_HOST=... to switch to real SMTP (skipped here — out of scope
for R6 demo). The function ALWAYS returns a result; never raises.
"""

import os, json, time, smtplib
from email.message import EmailMessage
from datetime import datetime
from pathlib import Path
from typing import Dict, Optional

MAILBOX_DIR = Path(os.environ.get("PGZ_MAILBOX_DIR", "/tmp/pgz_mailbox"))
MAILBOX_DIR.mkdir(parents=True, exist_ok=True)
INDEX_FILE = MAILBOX_DIR / "INDEX.jsonl"

DEFAULT_FROM   = os.environ.get("PGZ_MAIL_FROM", "no-reply@pgz.hr")
DEFAULT_SENDER = os.environ.get("PGZ_MAIL_SENDER", "PGŽ Sport platforma")

def send_email(to: str, subject: str, body: str,
               html: Optional[str] = None,
               from_addr: Optional[str] = None,
               metadata: Optional[Dict] = None) -> Dict:
    """Send (or mock-send) an email. Returns a dict with status + storage info."""
    sender = from_addr or DEFAULT_FROM
    msg = EmailMessage()
    msg["From"] = f"{DEFAULT_SENDER} <{sender}>"
    msg["To"] = to
    msg["Subject"] = subject
    msg["Date"] = datetime.utcnow().strftime("%a, %d %b %Y %H:%M:%S +0000")
    msg.set_content(body)
    if html:
        msg.add_alternative(html, subtype="html")

    smtp_host = os.environ.get("PGZ_SMTP_HOST")
    use_real = bool(smtp_host)
    sent_at = int(time.time())
    fname = f"{sent_at}-{to.replace('@','_at_')}.eml"
    fpath = MAILBOX_DIR / fname

    try:
        with open(fpath, "wb") as f:
            f.write(bytes(msg))
    except Exception as e:
        print(f"[MAILER WARN] cannot write {fpath}: {e}")

    rec = {
        "ts": sent_at,
        "to": to, "from": sender, "subject": subject,
        "file": str(fpath),
        "real_send": use_real,
        "metadata": metadata or {},
    }
    try:
        with open(INDEX_FILE, "a") as f:
            f.write(json.dumps(rec, ensure_ascii=False) + "\n")
    except Exception: pass

    if use_real:
        try:
            port = int(os.environ.get("PGZ_SMTP_PORT", "587"))
            user = os.environ.get("PGZ_SMTP_USER")
            pwd  = os.environ.get("PGZ_SMTP_PASS")
            with smtplib.SMTP(smtp_host, port, timeout=10) as s:
                s.starttls()
                if user: s.login(user, pwd or "")
                s.send_message(msg)
            rec["sent"] = True
        except Exception as e:
            rec["sent"] = False
            rec["error"] = str(e)
            print(f"[MAILER ERROR] {e}")
    else:
        # demo / dev mode — print preview to stdout
        print(f"[MOCK-MAIL] → {to} | {subject}")
        print(f"[MOCK-MAIL]   stored at {fpath}")
        rec["sent"] = True
        rec["mock"] = True

    return rec

# ─────────────────────────── Convenience helpers ───────────────────────────
def send_password_reset(email: str, reset_link: str, expires_in_seconds: int) -> Dict:
    hours = expires_in_seconds / 3600
    body = (
        f"Pozdrav,\n\n"
        f"Zatraženo je resetiranje lozinke za vaš račun na PGŽ Sport platformi.\n\n"
        f"Otvorite ovaj link za postavljanje nove lozinke (vrijedi {hours:.0f} h):\n"
        f"{reset_link}\n\n"
        f"Ako niste vi tražili promjenu, ignorirajte ovu poruku.\n\n"
        f"— PGŽ Sport platforma"
    )
    html = (
        f'<p>Pozdrav,</p>'
        f'<p>Zatraženo je resetiranje lozinke za vaš račun na PGŽ Sport platformi.</p>'
        f'<p><a href="{reset_link}" style="background:#00f0ff;color:#000;padding:10px 20px;'
        f'text-decoration:none;border-radius:6px;font-weight:600">Postavi novu lozinku</a></p>'
        f'<p style="font-size:12px;color:#888">Link vrijedi {hours:.0f} h.</p>'
    )
    return send_email(email, "Resetiranje lozinke — PGŽ Sport", body, html=html,
                       metadata={"kind": "password_reset"})

def send_invite(email: str, invite_link: str, expires_in_seconds: int,
                inviter: Optional[str] = None,
                role: Optional[str] = None) -> Dict:
    days = expires_in_seconds / 86400
    by = f" od {inviter}" if inviter else ""
    body = (
        f"Pozdrav,\n\n"
        f"Pozvani ste{by} u PGŽ Sport platformu" +
        (f" kao {role}" if role else "") + ".\n\n"
        f"Otvorite ovaj link i postavite svoju lozinku (vrijedi {days:.0f} dana):\n"
        f"{invite_link}\n\n"
        f"— PGŽ Sport platforma"
    )
    html = (
        f'<p>Pozdrav,</p>'
        f'<p>Pozvani ste{by} u PGŽ Sport platformu' +
        (f' kao <strong>{role}</strong>' if role else '') + '.</p>'
        f'<p><a href="{invite_link}" style="background:#00f0ff;color:#000;padding:10px 20px;'
        f'text-decoration:none;border-radius:6px;font-weight:600">Postavi lozinku i prijavi se</a></p>'
        f'<p style="font-size:12px;color:#888">Pozivnica vrijedi {days:.0f} dana.</p>'
    )
    return send_email(email, "Pozivnica — PGŽ Sport", body, html=html,
                       metadata={"kind": "invite", "role": role})