import os
import smtplib
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart

from app.core.config import settings

class EmailManager:
    @staticmethod
    def _render_template(template_key: str, variables: dict, lang: str = "hu") -> str:
        base_dir = "/app/app/templates/emails"
        file_path = f"{base_dir}/{lang}/{template_key}.html"
        if not os.path.exists(file_path):
            return ""
        with open(file_path, "r", encoding="utf-8") as f:
            body_html = f.read()
        for k, v in variables.items():
            body_html = body_html.replace(f"{{{{{k}}}}}", str(v))
            body_html = body_html.replace(f"{{{k}}}", str(v))
        return body_html

    @staticmethod
    def _subject(template_key: str) -> str:
        subjects = {
            "registration": "Regisztráció - Service Finder",
            "password_reset": "Jelszó visszaállítás - Service Finder",
            "notification": "Értesítés - Service Finder",
        }
        return subjects.get(template_key, "Értesítés - Service Finder")

    @staticmethod
    async def send_email(recipient: str, template_key: str, variables: dict, user_id: int = None, lang: str = "hu"):
        if settings.EMAIL_PROVIDER == "disabled":
            return {"status": "disabled"}

        html = EmailManager._render_template(template_key, variables, lang=lang)
        subject = EmailManager._subject(template_key)

        provider = settings.EMAIL_PROVIDER
        if provider == "auto":
            provider = "sendgrid" if settings.SENDGRID_API_KEY else "smtp"

        # 1) SendGrid API (stabil)
        if provider == "sendgrid" and settings.SENDGRID_API_KEY:
            try:
                from sendgrid import SendGridAPIClient
                from sendgrid.helpers.mail import Mail

                message = Mail(
                    from_email=(settings.EMAILS_FROM_EMAIL, settings.EMAILS_FROM_NAME),
                    to_emails=recipient,
                    subject=subject,
                    html_content=html or "<p>Üzenet</p>",
                )
                sg = SendGridAPIClient(settings.SENDGRID_API_KEY)
                sg.send(message)
                return {"status": "success", "provider": "sendgrid"}
            except Exception as e:
                # ha auto módban vagyunk, esünk vissza smtp-re
                if settings.EMAIL_PROVIDER != "auto":
                    return {"status": "error", "provider": "sendgrid", "message": str(e)}

        # 2) SMTP fallback
        if not settings.SMTP_HOST or not settings.SMTP_USER or not settings.SMTP_PASSWORD:
            return {"status": "error", "provider": "smtp", "message": "SMTP not configured"}

        try:
            msg = MIMEMultipart()
            msg["From"] = f"{settings.EMAILS_FROM_NAME} <{settings.EMAILS_FROM_EMAIL}>"
            msg["To"] = recipient
            msg["Subject"] = subject
            msg.attach(MIMEText(html or "Üzenet", "html"))

            with smtplib.SMTP(settings.SMTP_HOST, settings.SMTP_PORT, timeout=15) as server:
                if settings.SMTP_USE_TLS:
                    server.starttls()
                server.login(settings.SMTP_USER, settings.SMTP_PASSWORD)
                server.send_message(msg)

            return {"status": "success", "provider": "smtp"}
        except Exception as e:
            return {"status": "error", "provider": "smtp", "message": str(e)}

email_manager = EmailManager()