use std::fmt::Display;
use time::OffsetDateTime;
use pretty::RcDoc;

pub struct PrintableConversation {
    pub guid: String,
    pub date: OffsetDateTime,
    pub unread_count: i32,
    pub last_message_preview: Option<String>,
    pub participants: Vec<String>,
    pub display_name: Option<String>,
}

impl From<kordophone::model::Conversation> for PrintableConversation {
    fn from(value: kordophone::model::Conversation) -> Self {
        Self {
            guid: value.guid, 
            date: value.date,
            unread_count: value.unread_count,
            last_message_preview: value.last_message_preview,
            participants: value.participant_display_names,
            display_name: value.display_name,
        }
    }
}

impl From<kordophone_db::models::Conversation> for PrintableConversation {
    fn from(value: kordophone_db::models::Conversation) -> Self {
        Self {
            guid: value.guid,
            date: OffsetDateTime::from_unix_timestamp(value.date.and_utc().timestamp()).unwrap(),
            unread_count: value.unread_count.into(),
            last_message_preview: value.last_message_preview,
            participants: value.participants.into_iter().map(|p| p.display_name).collect(),
            display_name: value.display_name,
        }
    }
}

pub struct ConversationPrinter<'a> {
    doc: RcDoc<'a, PrintableConversation>
}

impl<'a> ConversationPrinter<'a> {
    pub fn new(conversation: &'a PrintableConversation) -> Self {
        let preview = conversation.last_message_preview
            .as_deref()
            .unwrap_or("<null>")
            .replace('\n', " ");

        let doc = RcDoc::text(format!("<Conversation: \"{}\"", &conversation.guid))
            .append(
                RcDoc::line()
                    .append("Display Name: ")
                    .append(conversation.display_name.as_deref().unwrap_or("<null>"))
                .append(RcDoc::line())
                    .append("Date: ")
                    .append(conversation.date.to_string())
                .append(RcDoc::line())
                    .append("Participants: ")
                    .append("[")
                    .append(RcDoc::line()
                        .append(
                            conversation.participants
                                .iter()
                                .map(|name| 
                                    RcDoc::text(name)
                                        .append(",")
                                        .append(RcDoc::line())
                                )
                                .fold(RcDoc::nil(), |acc, x| acc.append(x))
                        )
                        .nest(4)
                    )
                    .append("]")
                .append(RcDoc::line())
                    .append("Last Message Preview: ")
                    .append(preview)
                .nest(4)
            )
            .append(RcDoc::line())
            .append(">");

        ConversationPrinter { doc }
    }
}

impl<'a> Display for ConversationPrinter<'a> {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        self.doc.render_fmt(180, f)
    }
}