from app.config import settings
from app.models import (
    ConversationState,
    SenderType,
    TextMessage,
    TextMessageAttachment,
    User,
)


class FansifterConnector:
    def __init__(self) -> None:
        self.state = ConversationState.GREETING

    def _create(
        self, text: str, attachments: list[TextMessageAttachment] | None = None
    ) -> TextMessage:
        return TextMessage(
            sender=SenderType.fansifter,
            text=text,
            attachments=attachments or [],
        )

    async def handle_incoming_message(
        self,
        message: str,
        user: User,
    ) -> list[TextMessage]:
        norm = message.strip().lower()
        handler = self._state_handlers().get(self.state)
        if handler:
            return handler(norm, user)
        return []

    def _state_handlers(self):
        return {
            ConversationState.GREETING: self._handle_greeting,
            ConversationState.OPT_IN_ASKED: self._handle_opt_in_asked,
            ConversationState.OPTED_IN: self._handle_opted_in,
            ConversationState.OPTED_OUT: self._handle_opted_out,
        }

    def _handle_greeting(self, message: str, user: User) -> list[TextMessage]:
        self.state = ConversationState.OPT_IN_ASKED
        opt_in = user.settings.fansifter_settings.opt_in
        opt_in_terms = user.settings.fansifter_settings.opt_in_terms

        if message == "start":
            return [self._create(opt_in_terms)]
        if message == "stop":
            return []
        return [self._create(opt_in + "\n" + opt_in_terms)]

    def _handle_opt_in_asked(self, message: str, user: User) -> list[TextMessage]:
        welcome = user.settings.fansifter_settings.welcome
        welcome_instructions = user.settings.fansifter_settings.welcome_instructions
        vcard = self._build_vcard_attachment(user)

        if message != "yes":
            return []

        self.state = ConversationState.OPTED_IN
        return [
            self._create(
                welcome + "\n" + welcome_instructions, attachments=[vcard] if vcard else []
            )
        ]

    def _handle_opted_in(self, message: str, user: User) -> list[TextMessage]:
        info = user.settings.fansifter_settings.info

        if message == "info":
            return [self._create(info)]

        if message == "stop":
            self.state = ConversationState.OPTED_OUT

        return []

    def _handle_opted_out(self, message: str, _user: User | None = None) -> list[TextMessage]:
        if message == "start":
            self.state = ConversationState.OPTED_IN

        return []

    def _build_vcard_attachment(self, user: User) -> TextMessageAttachment | None:
        if settings.default_user_settings is None:
            return None
        phone_number = "+1-555-0100"
        lines = [
            "BEGIN:VCARD",
            "VERSION:3.0",
            f"FN:{user.settings.app_settings.artist_name}",
            f"TEL;TYPE=CELL:{phone_number}",
            "END:VCARD",
        ]
        content = "\r\n".join(lines).encode("utf-8")
        return TextMessageAttachment(
            type="vcard",
            content=content,
            filename=f"{user.settings.app_settings.artist_name.replace(' ', '_')}.vcf",
            mimetype="text/vcard",
        )