#![allow(unused_variables)]
use crate::prelude::{Host, Mailbox, Mailuser, Message};
use std::{collections::HashMap, io, str::FromStr};

#[cfg(feature = "serde")]
use serde::{Deserialize, Serialize};

pub mod filesystem;

pub trait MailStore {
    type Error;

    /// Retreives a list of all valid mailusers on this server
    fn users(&self) -> Vec<Mailuser>;
    /// Checks whether this server services that domain
    fn serves_domain(&self, domain: &str) -> bool;
    /// Checks whether this server has the given mailuser
    fn has_mailuser(&self, mailuser: &str) -> bool;
    /// Retreives all of the messages for this user
    fn get_folder(&self, user: &str, folder: &str) -> Option<Folder>;
    /// Checks whether this server has a message with the given title for this user and if so
    /// returns the message
    fn get_message(&self, user: &str, folder: &str, title: &str) -> Option<Message>;
    /// Move a message to a new folder
    fn move_message(
        &mut self,
        user: &str,
        id: &str,
        folder1: &str,
        folder2: &str,
    ) -> Result<(), Self::Error>;
    /// Deletes a message it it exists
    fn delete_message(&mut self, user: &str, folder: &str, id: &str) -> Result<(), Self::Error>;
    /// Adds a message
    fn add_message(
        &mut self,
        user: &str,
        folder: &str,
        message: Message,
    ) -> Result<(), Self::Error>;
    /// Adds a new mailuser to the given domain
    fn add_user(&mut self, user: &str) -> Result<(), Self::Error>;
    /// Removes the given user if the account exists
    fn remove_user(&mut self, user: &str) -> bool;
}

#[derive(Clone, Debug)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
pub struct Domain {
    pub host: Host,
    pub users: HashMap<String, Account>,
}

#[derive(Clone, Debug)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
pub struct Account {
    pub user: Mailbox,
    pub folders: HashMap<String, Folder>,
}

#[derive(Clone, Debug)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
pub struct Folder {
    pub name: String,
    pub messages: HashMap<String, Message>,
}

#[derive(Debug)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
pub struct MultiDomain {
    pub domains: HashMap<String, Domain>,
}

impl MailStore for Domain {
    type Error = io::Error;

    fn users(&self) -> Vec<Mailuser> {
        self.users
            .values()
            .map(|act| act.user.clone().into())
            .collect()
    }

    fn serves_domain(&self, domain: &str) -> bool {
        self.host.to_string().as_str() == domain
    }

    fn has_mailuser(&self, mailuser: &str) -> bool {
        self.users().iter().any(|x| x.username == mailuser)
    }

    fn get_folder(&self, user: &str, folder: &str) -> Option<Folder> {
        self.users
            .get(user)
            .cloned()
            .and_then(|u| u.folders.get(folder).cloned())
    }

    fn get_message(&self, user: &str, folder: &str, title: &str) -> Option<Message> {
        self.users
            .get(user)
            .and_then(|u| {
                u.folders.get(folder).and_then(|f| {
                    f.messages
                        .values()
                        .find(|m| m.title.as_ref().map(String::as_str) == Some(title))
                })
            })
            .cloned()
    }

    fn move_message(
        &mut self,
        user: &str,
        id: &str,
        folder1: &str,
        folder2: &str,
    ) -> Result<(), Self::Error> {
        todo!()
    }

    fn add_user(&mut self, user: &str) -> Result<(), Self::Error> {
        if self.users.contains_key(user) {
            return Ok(());
        }
        let mbox = Mailbox::from_str(&format!("{user}@{}", self.host))
            .map_err(|e| io::Error::new(io::ErrorKind::Other, format!("{e}")))?;
        let folders = HashMap::new();
        let acct = Account {
            user: mbox,
            folders,
        };
        self.users.insert(user.to_string(), acct);
        Ok(())
    }

    fn remove_user(&mut self, user: &str) -> bool {
        self.users.remove(user).is_some()
    }

    fn add_message(
        &mut self,
        user: &str,
        folder: &str,
        message: Message,
    ) -> Result<(), Self::Error> {
        todo!()
    }

    fn delete_message(&mut self, user: &str, folder: &str, id: &str) -> Result<(), Self::Error> {
        todo!()
    }
}