/*!
 * matrix-lolopener v0.1.0
 *
 * Copyright (C) 2026 The 1312 Media Collective
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

use serde::Deserialize;
use std::{fs, io, fmt};

#[derive(Deserialize, Debug, Clone)]
pub struct MQTTConfig {
    pub id: String,
    pub host: String,
    pub port: u16,
    pub topic: String,
}

#[derive(Deserialize, Debug)]
#[serde(untagged)]
pub enum AuthConfig {
    PasswordAuthConfig {
        username: String,
        password: String,
    },
    TokenAuthConfig {
        user_id: String,
        device_id: String,
        access_token: String,
    }
}

#[derive(Deserialize, Debug)]
pub struct Config {
    pub mqtt: MQTTConfig,
    pub rooms: Vec<String>,
    pub debounce_delay: u64,
    #[serde(flatten)]
    pub auth: AuthConfig,
    pub homeserver_uri: String
}

impl Config {
    pub fn load(config_file: &str) -> Result<Self> {

        let serialized_config = fs::read_to_string(config_file).map_err(|e| {
            match e.kind() {
                io::ErrorKind::NotFound => Error::FileNotFound(config_file.into()),
                io::ErrorKind::PermissionDenied => Error::PermissionDenied(),
                _ => e.into(),
            }
        })?;

        let config: Config = serde_yaml::from_str(&serialized_config)?;

        Ok(config)
    }
}

#[derive(Debug)]
#[allow(dead_code)] // we use Debug, so inner fields are never read
pub enum Error {
    FileNotFound(String),
    PermissionDenied(),
    InvalidFormat(serde_yaml::Error),
    Io(io::Error),
}

impl From<serde_yaml::Error> for Error {
    fn from(e: serde_yaml::Error) -> Self {
        Self::InvalidFormat(e)
    }
}

impl From<io::Error> for Error {
    fn from(e: io::Error) -> Self {
        Self::Io(e)
    }
}

impl std::error::Error for Error {}

impl fmt::Display for Error {
    fn fmt(&self, fmt: &mut fmt::Formatter) -> std::result::Result<(), fmt::Error> {
        write!(fmt, "{self:?}")
    }
}

pub type Result<T> = std::result::Result<T, Error>;