use embedded_graphics::{
    mono_font::{MonoTextStyleBuilder, ascii::FONT_6X10},
    pixelcolor::BinaryColor,
    prelude::Point,
    text::{Baseline, Text},
    draw_target::DrawTarget,
    Drawable,
};
use ssd1306::{prelude::*, I2CDisplayInterface, Ssd1306, mode::BufferedGraphicsMode};
use embassy_rp::i2c::I2c;
use core::fmt::Write;

/// Display type encapsulating the I2C interface, its size and graphics mode
pub type Display = Ssd1306<
    I2CInterface<I2c<'static, embassy_rp::peripherals::I2C0, embassy_rp::i2c::Async>>,
    DisplaySize128x32,
    BufferedGraphicsMode<DisplaySize128x32>
>;

/// Function that initializes the display with given settings
pub fn init_display(bus: I2c<'static, embassy_rp::peripherals::I2C0, embassy_rp::i2c::Async>) -> Option<Display> {
    let interface = I2CDisplayInterface::new(bus);
    let mut display = Ssd1306::new(
        interface,
        DisplaySize128x32,
        DisplayRotation::Rotate180,
    )
    .into_buffered_graphics_mode();

    match display.init() {
        Ok(_) => Some(display),
        Err(_) => None,
    }
}

/// Temp function which updates the display with currently pressed keys
pub fn update_display(
    display: &mut Option<Display>,
    pressed_keys: &[(usize, usize, crate::keymap::KeyCode)],
) -> Option<()> {
    if let Some(display) = display {
        display.clear(BinaryColor::Off).ok()?;
    
        let text_style = MonoTextStyleBuilder::new()
            .font(&FONT_6X10)
            .text_color(BinaryColor::On)
            .build();
    
        if pressed_keys.is_empty() {
            Text::with_baseline("No keys", Point::zero(), text_style, Baseline::Top)
                .draw(display)
                .ok()?;
        } else {
            let mut y_pos = 0;
            for (row_idx, col_idx, keycode) in pressed_keys.iter().take(3) {
                let mut msg = heapless::String::<32>::new();
                write!(&mut msg, "R{}C{}: 0x{:02X}", row_idx, col_idx, keycode.as_u8()).ok();
    
                Text::with_baseline(&msg, Point::new(0, y_pos), text_style, Baseline::Top)
                    .draw(display)
                    .ok()?;
    
                y_pos += 10;
            }
        }
    
        display.flush().ok()?;
        Some(())
    } else {
        None
    }
}

/// Helper function to clear the display
pub fn clear_display(
    display: &mut Option<Display>,
) -> Option<()> {
    if let Some(display) = display {
        display.clear(BinaryColor::Off).ok()?;
        display.flush().ok()?;
        Some(())
    } else {
        None
    }
}