use std::collections::HashMap;

use winit::{
    event::KeyEvent,
    keyboard::{KeyCode, PhysicalKey},
};

use crate::emulator::{SimId, VBKey};

pub struct InputMapper {
    vb_bindings: HashMap<SimId, HashMap<VBKey, PhysicalKey>>,
    key_bindings: HashMap<PhysicalKey, (SimId, VBKey)>,
}

impl InputMapper {
    pub fn new() -> Self {
        let mut mapper = Self {
            vb_bindings: HashMap::new(),
            key_bindings: HashMap::new(),
        };
        mapper.bind_key(SimId::Player1, VBKey::SEL, PhysicalKey::Code(KeyCode::KeyA));
        mapper.bind_key(SimId::Player1, VBKey::STA, PhysicalKey::Code(KeyCode::KeyS));
        mapper.bind_key(SimId::Player1, VBKey::B, PhysicalKey::Code(KeyCode::KeyD));
        mapper.bind_key(SimId::Player1, VBKey::A, PhysicalKey::Code(KeyCode::KeyF));
        mapper.bind_key(SimId::Player1, VBKey::LT, PhysicalKey::Code(KeyCode::KeyE));
        mapper.bind_key(SimId::Player1, VBKey::RT, PhysicalKey::Code(KeyCode::KeyR));
        mapper.bind_key(SimId::Player1, VBKey::RU, PhysicalKey::Code(KeyCode::KeyI));
        mapper.bind_key(SimId::Player1, VBKey::RL, PhysicalKey::Code(KeyCode::KeyJ));
        mapper.bind_key(SimId::Player1, VBKey::RD, PhysicalKey::Code(KeyCode::KeyK));
        mapper.bind_key(SimId::Player1, VBKey::RR, PhysicalKey::Code(KeyCode::KeyL));
        mapper.bind_key(
            SimId::Player1,
            VBKey::LU,
            PhysicalKey::Code(KeyCode::ArrowUp),
        );
        mapper.bind_key(
            SimId::Player1,
            VBKey::LL,
            PhysicalKey::Code(KeyCode::ArrowLeft),
        );
        mapper.bind_key(
            SimId::Player1,
            VBKey::LD,
            PhysicalKey::Code(KeyCode::ArrowDown),
        );
        mapper.bind_key(
            SimId::Player1,
            VBKey::LR,
            PhysicalKey::Code(KeyCode::ArrowRight),
        );
        mapper
    }

    pub fn binding_names(&self, sim_id: &SimId) -> HashMap<VBKey, String> {
        let Some(bindings) = self.vb_bindings.get(sim_id) else {
            return HashMap::new();
        };
        bindings
            .iter()
            .map(|(k, v)| {
                let name = match v {
                    PhysicalKey::Code(code) => format!("{code:?}"),
                    k => format!("{:?}", k),
                };
                (*k, name)
            })
            .collect()
    }

    pub fn bind_key(&mut self, sim_id: SimId, vb: VBKey, key: PhysicalKey) {
        let vb_bindings = self.vb_bindings.entry(sim_id).or_default();
        if let Some(old) = vb_bindings.insert(vb, key) {
            self.key_bindings.remove(&old);
        }
        self.key_bindings.insert(key, (sim_id, vb));
    }

    pub fn clear_binding(&mut self, sim_id: SimId, vb: VBKey) {
        let vb_bindings = self.vb_bindings.entry(sim_id).or_default();
        if let Some(old) = vb_bindings.remove(&vb) {
            self.key_bindings.remove(&old);
        }
    }

    pub fn key_event(&self, event: &KeyEvent) -> Option<(SimId, VBKey)> {
        self.key_bindings.get(&event.physical_key).copied()
    }
}