use crate::peripherals::{BlendMode, Gfx, InputSignals, Pad, Touch};
use crate::Color;

/// PROMETEU "hardware lógico" (v0).
/// O Host alimenta INPUT SIGNALS e chama `step_frame()` em 60Hz.
pub struct Machine {
    pub gfx: Gfx,
    pub pad: Pad,
    pub touch: Touch,
    pub frame_index: u64,
}

impl Machine {
    pub const W: usize = 320;
    pub const H: usize = 180;

    pub fn new() -> Self {
        Self {
            gfx: Gfx::new(Self::W, Self::H),
            pad: Pad::default(),
            touch: Touch::default(),
            frame_index: 0,
        }
    }

    /// "Contrato de frame" do PROMETEU (Template Method sem loop).
    /// O Host controla tempo/event loop; o Core define a sequência do frame.
    pub fn step_frame(&mut self, signals: &InputSignals) {
        self.begin_frame(signals);
        self.tick();       // futuro: executa cartucho/VM
        self.end_frame();  // present/housekeeping
    }

    /// Início do frame: zera flags transitórias.
    pub fn begin_frame(&mut self, signals: &InputSignals) {
        self.frame_index += 1;

        // Flags transitórias do TOUCH devem durar 1 frame.
        self.touch.begin_frame(signals);

        // Se você quiser input com pressed/released depois:
        self.pad.begin_frame(signals);
    }

    /// Lógica do frame (demo hardcoded por enquanto).
    pub fn tick(&mut self) {
        self.gfx.clear(Color::rgb(0x10, 0x10, 0x10));

        let (x, y) = self.demo_pos();

        let color = if self.pad.a.down || self.touch.f.down {
            Color::rgb(0x00, 0xFF, 0x00)
        } else {
            Color::rgb(0xFF, 0x40, 0x40)
        };

        // game
        self.gfx.fill_rect(x, y, 20, 20, color);
        // smoke
        self.gfx.fill_rect_blend(140, 0, 40, 180, Color::gray_scale(0x88), BlendMode::Half)
    }

    /// Final do frame: troca buffers.
    pub fn end_frame(&mut self) {
        self.gfx.present();
    }

    fn demo_pos(&self) -> (i32, i32) {
        let x = (self.frame_index % 300) as i32;
        let y = (self.pad.a.hold_frames % 160) as i32;
        (x, y)
    }
}