"""Email message model and parsing.

Parses RFC 822 email messages for display in the web UI.

Ported from i2p.susi.webmail.Mail.
"""

from __future__ import annotations

from dataclasses import dataclass, field
from datetime import datetime


@dataclass
class MailMessage:
    """An email message."""
    sender: str
    recipient: str
    subject: str
    body: str
    date: str = ""
    message_id: str = ""
    read: bool = False


def parse_email(raw: str) -> MailMessage:
    """Parse a raw RFC 822 email string into a MailMessage."""
    headers: dict[str, str] = {}
    lines = raw.split("\r\n") if "\r\n" in raw else raw.split("\n")

    body_start = 0
    for i, line in enumerate(lines):
        if line.strip() == "":
            body_start = i + 1
            break
        if ":" in line:
            key, value = line.split(":", 1)
            headers[key.strip().lower()] = value.strip()

    body = "\r\n".join(lines[body_start:]) if "\r\n" in raw else "\n".join(lines[body_start:])

    return MailMessage(
        sender=headers.get("from", ""),
        recipient=headers.get("to", ""),
        subject=headers.get("subject", ""),
        body=body,
        date=headers.get("date", ""),
        message_id=headers.get("message-id", ""),
    )