#![no_std]
#![no_main]

use atmega_hal::{
    clock::MHz8,
    delay::Delay,
    pins,
    spi::{DataOrder, SerialClockRate, Settings, Spi},
    Peripherals,
};
use avr_device::interrupt;
use embedded_hal::{
    blocking::delay::DelayMs,
    spi::{FullDuplex, Mode, Phase, Polarity},
};
use nb::block;
use panic_halt as _;

#[atmega_hal::entry]
fn main() -> ! {
    // Disable interrupts when initializing
    interrupt::disable();

    // Get peripherals, pins and delay
    let dp = Peripherals::take().unwrap();
    let pins = pins!(dp);
    let mut delay = Delay::<MHz8>::new();

    // Init display backlight
    let tc0 = dp.TC0;
    tc0.tccr0a.write(|w| {
        w.wgm0().pwm_fast();
        w.com0b().match_clear();
        w
    });
    tc0.tccr0b.write(|w| {
        w.wgm02().set_bit();
        w.cs0().prescale_64();
        w
    });
    tc0.ocr0a.write(|w| unsafe { w.bits(255) });
    // TODO: Use EEPROM
    tc0.ocr0b.write(|w| unsafe { w.bits(0) });
    pins.pd5.into_output();

    // Init SPI
    let (mut spi, _) = Spi::new(
        dp.SPI,
        pins.pb5.into_output(),
        pins.pb3.into_output(),
        pins.pb4.into_pull_up_input(),
        pins.pb2.into_output(),
        Settings {
            data_order: DataOrder::MostSignificantFirst,
            clock: SerialClockRate::OscfOver2,
            mode: Mode {
                polarity: Polarity::IdleLow,
                phase: Phase::CaptureOnFirstTransition,
            },
        },
    );

    // Init LCD
    let mut lcd_cd = pins.pb0.into_output();
    let mut lcd_rst = pins.pb1.into_output();
    // TODO: Test if delay is really needed
    delay.delay_ms(1_u8);
    lcd_rst.set_high();
    // TODO: Try to reduce delay to a minimum
    delay.delay_ms(5_u8);

    block!(spi.send(0x40)).unwrap(); // (6)  Set Scroll Line: Display start line 0
    block!(spi.send(0xA1)).unwrap(); // (13) Set SEG direction: SEG reverse
    block!(spi.send(0xC0)).unwrap(); // (14) Set COM direction: Normal COM0 - COM63
    block!(spi.send(0xA6)).unwrap(); // (11) Set Inverse Display: Display inverse off
    block!(spi.send(0xA2)).unwrap(); // (17) Set LCD Bias Ratio: Set Bias 1/9 (Duty 1/65)
    block!(spi.send(0x2F)).unwrap(); // (5)  Set Power Control: Booster, Regulator and Follower on
    block!(spi.send(0x27)).unwrap(); // (8)  Set VLCD Resistor Ratio: Set Contrast
    block!(spi.send(0x81)).unwrap(); // (9)  Set Electronic Volume: Set Contrast
    block!(spi.send(0x08)).unwrap(); // (9)  Set Electronic Volume: Set Contrast // TODO: Use EEPROM
    block!(spi.send(0xAF)).unwrap(); // (12) Set Display Enable: Display on

    // Clear screen
    for page in 0..8 {
        block!(spi.send(0x00)).unwrap();
        block!(spi.send(0x10)).unwrap();
        block!(spi.send(0xB0 + page)).unwrap();

        // TODO: This delay fixes issues, try find a better solution
        delay.delay_ms(1_u8);
        lcd_cd.set_high();

        for _ in 0..102 {
            block!(spi.send(0x00)).unwrap();
        }

        // TODO: This delay fixes issues, try find a better solution
        delay.delay_ms(1_u8);
        lcd_cd.set_low();
    }

    // Enable interrupts
    unsafe { interrupt::enable() };

    #[allow(clippy::empty_loop)]
    loop {}
}