/*
 * mCaptcha - A proof of work based DoS protection system
 * Copyright © 2021 Aravinth Manivannan <realravinth@batsense.net>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
//! [Master] actor module that manages [MCaptcha] actors
use std::sync::mpsc::Receiver;

use actix::dev::*;
use derive_builder::Builder;
use serde::{Deserialize, Serialize};

pub mod embedded;

use crate::defense::Defense;
use crate::errors::*;

/// Describes actor handler trait impls that are required by a cache implementation
pub trait Master: actix::Actor + actix::Handler<AddVisitor> + actix::Handler<AddSite> {}

//+ actix::Handler<AddSite>

/// Message to add visitor to an [MCaptcha] actor
#[derive(Message)]
#[rtype(result = "Option<Receiver<AddVisitorResult>>")]
pub struct AddVisitor(pub String);

/// Struct representing the return datatime of
/// [AddVisitor] message. Contains MCaptcha lifetime
/// and difficulty factor
#[derive(Debug, Clone, Deserialize, Serialize)]
pub struct AddVisitorResult {
    pub duration: u64,
    pub difficulty_factor: u32,
}

/// Message to add an [Counter] actor to [Master]
#[derive(Message, Builder)]
#[rtype(result = "()")]
pub struct AddSite {
    pub id: String,
    pub mcaptcha: MCaptcha,
}

/// Builder for [MCaptcha]
#[derive(Clone, Serialize, Deserialize, Debug)]
pub struct MCaptchaBuilder {
    visitor_threshold: u32,
    defense: Option<Defense>,
    duration: Option<u64>,
}

impl Default for MCaptchaBuilder {
    fn default() -> Self {
        MCaptchaBuilder {
            visitor_threshold: 0,
            defense: None,
            duration: None,
        }
    }
}

impl MCaptchaBuilder {
    /// set defense
    pub fn defense(&mut self, d: Defense) -> &mut Self {
        self.defense = Some(d);
        self
    }

    /// set duration
    pub fn duration(&mut self, d: u64) -> &mut Self {
        self.duration = Some(d);
        self
    }

    /// Builds new [MCaptcha]
    pub fn build(self: &mut MCaptchaBuilder) -> CaptchaResult<MCaptcha> {
        if self.duration.is_none() {
            Err(CaptchaError::PleaseSetValue("duration".into()))
        } else if self.defense.is_none() {
            Err(CaptchaError::PleaseSetValue("defense".into()))
        } else if self.duration <= Some(0) {
            Err(CaptchaError::CaptchaDurationZero)
        } else {
            let m = MCaptcha {
                duration: self.duration.unwrap(),
                defense: self.defense.clone().unwrap(),
                visitor_threshold: self.visitor_threshold,
            };
            Ok(m)
        }
    }
}

#[derive(Clone, Serialize, Deserialize, Debug)]
pub struct MCaptcha {
    visitor_threshold: u32,
    defense: Defense,
    duration: u64,
}