use std::cmp::min;
use std::ops::{Index, IndexMut, Mul};

use glc::vector::Vector2f;
use serde::{Deserialize, Serialize};
use specs::{Component, Entity, VecStorage};

use crate::{builder::ShipBuilder, misc::FlaggedStorage};

#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct Ship {
    type_: ShipType,
    dir: Vector2f,

    #[serde(skip)]
    obstacle: ShipObstacle,

    #[serde(skip)]
    target_pos: Vector2f,

    #[serde(skip)]
    target_dir: Vector2f,
}

#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub enum ShipObstacle {
    Known(Entity),
    Search,
    Done,
}

#[derive(Copy, Clone, Debug, Default)]
pub struct ShipCount {
    pub fighter: usize,
    pub bomber: usize,
    pub transporter: usize,
}

#[derive(Clone, Default, Debug)]
pub struct ShipsData {
    pub fighter: ShipData,
    pub bomber: ShipData,
    pub transporter: ShipData,
}

#[derive(Clone, Default, Debug)]
pub struct ShipData {
    pub speed: f32,
}

#[derive(Copy, Clone, Debug, Serialize, Deserialize)]
pub enum ShipType {
    Fighter,
    Bomber,
    Transporter,
}

/* Ship */

impl Ship {
    #[inline]
    pub fn builder() -> ShipBuilder {
        ShipBuilder::default()
    }

    #[inline]
    pub fn type_(&self) -> ShipType {
        self.type_
    }

    #[inline]
    pub fn dir(&self) -> &Vector2f {
        &self.dir
    }

    #[inline]
    pub fn target_pos(&self) -> &Vector2f {
        &self.target_pos
    }

    #[inline]
    pub fn target_dir(&self) -> &Vector2f {
        &self.target_dir
    }

    #[inline]
    pub fn obstacle(&self) -> ShipObstacle {
        self.obstacle
    }
}

impl Ship {
    #[inline]
    pub(crate) fn new(type_: ShipType, dir: Vector2f) -> Self {
        Self {
            type_,
            dir,
            obstacle: Default::default(),
            target_pos: Default::default(),
            target_dir: Default::default(),
        }
    }

    #[inline]
    pub(crate) fn set_target(&mut self, pos: Vector2f, dir: Vector2f) {
        self.target_pos = pos;
        self.target_dir = dir;
    }

    #[inline]
    pub(crate) fn dir_mut(&mut self) -> &mut Vector2f {
        &mut self.dir
    }

    #[inline]
    pub(crate) fn obstacle_mut(&mut self) -> &mut ShipObstacle {
        &mut self.obstacle
    }
}

impl Component for Ship {
    type Storage = FlaggedStorage<Self, VecStorage<Self>>;
}

/* Obstacle */

impl Default for ShipObstacle {
    fn default() -> Self {
        Self::Search
    }
}

/* Count */

impl ShipCount {
    pub fn all() -> Self {
        Self {
            fighter: usize::MAX,
            bomber: usize::MAX,
            transporter: usize::MAX,
        }
    }

    pub fn none() -> Self {
        Self {
            fighter: 0,
            bomber: 0,
            transporter: 0,
        }
    }

    pub fn total(&self) -> usize {
        self.fighter
            .saturating_add(self.bomber)
            .saturating_add(self.transporter)
    }

    pub fn merge(&self, other: &Self) -> Self {
        Self {
            fighter: min(self.fighter, other.fighter),
            bomber: min(self.bomber, other.bomber),
            transporter: min(self.transporter, other.transporter),
        }
    }

    pub fn is_all(&self) -> bool {
        self.fighter == usize::MAX && self.bomber == usize::MAX && self.transporter == usize::MAX
    }
}

impl Index<usize> for ShipCount {
    type Output = usize;

    fn index(&self, index: usize) -> &Self::Output {
        match index {
            0 => &self.fighter,
            1 => &self.bomber,
            2 => &self.transporter,
            x => panic!("Invalid ship count index: {}", x),
        }
    }
}

impl IndexMut<usize> for ShipCount {
    fn index_mut(&mut self, index: usize) -> &mut Self::Output {
        match index {
            0 => &mut self.fighter,
            1 => &mut self.bomber,
            2 => &mut self.transporter,
            x => panic!("Invalid ship count index: {}", x),
        }
    }
}

impl Index<ShipType> for ShipCount {
    type Output = usize;

    fn index(&self, index: ShipType) -> &Self::Output {
        match index {
            ShipType::Fighter => &self.fighter,
            ShipType::Bomber => &self.bomber,
            ShipType::Transporter => &self.transporter,
        }
    }
}

impl IndexMut<ShipType> for ShipCount {
    fn index_mut(&mut self, index: ShipType) -> &mut Self::Output {
        match index {
            ShipType::Fighter => &mut self.fighter,
            ShipType::Bomber => &mut self.bomber,
            ShipType::Transporter => &mut self.transporter,
        }
    }
}

impl Mul<f32> for ShipCount {
    type Output = ShipCount;

    #[allow(unused_assignments)]
    fn mul(self, rhs: f32) -> Self::Output {
        let expected = self.total() as f32;
        let expected = (rhs * expected).ceil() as usize;

        let mut fighter = (rhs * self.fighter as f32) as usize;
        let mut bomber = (rhs * self.bomber as f32) as usize;
        let mut transporter = (rhs * self.transporter as f32) as usize;

        let mut actual = fighter.saturating_add(bomber).saturating_add(transporter);

        if actual < expected && fighter < self.fighter {
            fighter += 1;
            actual += 1;
        }

        if actual < expected && bomber < self.bomber {
            bomber += 1;
            actual += 1;
        }

        if actual < expected && transporter < self.transporter {
            transporter += 1;
            actual += 1;
        }

        ShipCount {
            fighter,
            bomber,
            transporter,
        }
    }
}

/* ShipsData */

impl Index<usize> for ShipsData {
    type Output = ShipData;

    fn index(&self, index: usize) -> &Self::Output {
        match index {
            0 => &self.fighter,
            1 => &self.bomber,
            2 => &self.transporter,
            x => panic!("Invalid ships data index: {}", x),
        }
    }
}

impl Index<ShipType> for ShipsData {
    type Output = ShipData;

    fn index(&self, index: ShipType) -> &Self::Output {
        match index {
            ShipType::Fighter => &self.fighter,
            ShipType::Bomber => &self.bomber,
            ShipType::Transporter => &self.transporter,
        }
    }
}