#![no_std]
#![no_main]
#![feature(ascii_char)]
#![deny(
    clippy::mem_forget,
    reason = "mem::forget is generally not safe to do with esp_hal types, especially those \
    holding buffers for the duration of a data transfer."
)]
#![deny(clippy::large_stack_frames)]

use core::mem::MaybeUninit;

use alloc::{boxed::Box, format, string::ToString};
use esp_hal::{
    clock::CpuClock,
    delay::Delay,
    gpio::{InputConfig, Level, Output, OutputConfig},
    interrupt::software::SoftwareInterruptControl,
    main,
    spi::master::{Config, Spi},
    system::Stack,
    time::Rate,
    timer::timg::TimerGroup,
    uart::{self, Uart},
};

use esp_backtrace as _;

use crate::{
    async_io::AsyncIO,
    at_commands::ATCommands,
    display::{Display, Position, Rgb565, SetAddressMode},
    font::FontRenderer,
    state::StateManager,
    states::InitATState,
};

extern crate alloc;

mod async_io;
mod at_commands;
mod display;
mod font;
mod state;
mod states;

// This creates a default app-descriptor required by the esp-idf bootloader.
// For more information see: <https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-reference/system/app_image_format.html#application-description>
esp_bootloader_esp_idf::esp_app_desc!();

#[allow(
    clippy::large_stack_frames,
    reason = "it's not unusual to allocate larger buffers etc. in main"
)]
#[main]
fn main() -> ! {
    // generator version: 1.3.0
    // generator parameters: --chip esp32 -o esp32-wroom-32e -o alloc -o esp-backtrace -o log -o vscode

    esp_println::logger::init_logger_from_env();

    let config = esp_hal::Config::default().with_cpu_clock(CpuClock::max());
    let peripherals = esp_hal::init(config);

    // The following pins are used to bootstrap the chip. They are available
    // for use, but check the datasheet of the module for more information on them.
    // - GPIO0
    // - GPIO2
    // - GPIO5
    // - GPIO12
    // - GPIO15
    // These GPIO pins are in use by some feature of the module and should not be used.
    let _ = peripherals.GPIO6;
    let _ = peripherals.GPIO7;
    let _ = peripherals.GPIO8;
    let _ = peripherals.GPIO9;
    let _ = peripherals.GPIO10;
    let _ = peripherals.GPIO11;
    let _ = peripherals.GPIO16;
    let _ = peripherals.GPIO17;

    esp_alloc::heap_allocator!(#[esp_hal::ram(reclaimed)] size: 98768);

    let spi = Spi::new(
        peripherals.SPI2,
        Config::default()
            .with_frequency(Rate::from_mhz(80))
            .with_mode(esp_hal::spi::Mode::_2)
            .with_read_bit_order(esp_hal::spi::BitOrder::MsbFirst)
            .with_write_bit_order(esp_hal::spi::BitOrder::MsbFirst),
    )
    .unwrap()
    .with_sck(peripherals.GPIO5)
    .with_mosi(peripherals.GPIO19)
    .with_miso(peripherals.GPIO21)
    .with_cs(peripherals.GPIO4);

    let rst = Output::new(peripherals.GPIO14, Level::Low, OutputConfig::default());
    let dc = Output::new(peripherals.GPIO32, Level::Low, OutputConfig::default());

    let mut display = Display {
        spi,
        dc,
        rst,
        delay: Delay::new(),
    };

    display.init(SetAddressMode {
        color_order: display::ColorOrder::Rgb,
        ..Default::default()
    });
    display.set_tearing(display::TearingMode::Off);

    let sim_rst = Output::new(peripherals.GPIO27, Level::High, OutputConfig::default());
    let sim_pwr_key = Output::new(peripherals.GPIO12, Level::High, OutputConfig::default());

    let uart = Uart::new(
        peripherals.UART2,
        uart::Config::default()
            .with_baudrate(115200)
            .with_data_bits(uart::DataBits::_8)
            .with_parity(uart::Parity::None)
            .with_sw_flow_ctrl(uart::SwFlowControl::Disabled),
    )
    .unwrap()
    .with_rx(peripherals.GPIO7)
    .with_tx(peripherals.GPIO8);

    let mut at_commands = ATCommands::new(sim_rst, sim_pwr_key, uart);

    let font_renderer = FontRenderer::create(30);
    display.clear(Rgb565::black().as_color());
    font_renderer.render(
        &mut display,
        "Please wait",
        Position::new(120, 120),
        font::HorizontalAlignment::Center,
        font::VerticalAlignment::Center,
        Rgb565::black(),
        Rgb565::white(),
    );

    at_commands.init();

    let async_io = AsyncIO::default();

    let mut state_mgr = StateManager {
        data: state::StateData::from(display, async_io.clone()),
        curr_state: Box::new(InitATState::default()),
    };

    static mut THREAD_2_STACK: Stack<{ 30 * 1024 }> = esp_hal::system::Stack {
        mem: MaybeUninit::new([0u8; 30 * 1024]),
    };

    let timg0 = TimerGroup::new(peripherals.TIMG0);
    let software_interrupt = SoftwareInterruptControl::new(peripherals.SW_INTERRUPT);
    esp_rtos::start(timg0.timer0, software_interrupt.software_interrupt0);
    esp_rtos::start_second_core(
        peripherals.CPU_CTRL,
        software_interrupt.software_interrupt1,
        unsafe {
            #[allow(static_mut_refs)]
            &mut THREAD_2_STACK
        },
        {
            let io = async_io.clone();
            || thread_2_main(io, at_commands)
        },
    );

    loop {
        state_mgr.update();
        state_mgr.draw();
    }

    // for inspiration have a look at the examples at https://github.com/esp-rs/esp-hal/tree/esp-hal-v1.1.0/examples
}

fn thread_2_main(async_io: AsyncIO, mut at_commands: ATCommands<'static, 'static>) {
    loop {
        if let Some(command) = unsafe { async_io.check_at_command() } {
            let response = match command {
                async_io::ConstructedATCommand::Single(cmd) => at_commands.raw_command(cmd),
                async_io::ConstructedATCommand::AddInfo(cmd, add) => {
                    at_commands.raw_two_part_command(cmd, add)
                }
            };
            unsafe { async_io.set_at_response(response) };
        }

        if let Some(event) = at_commands.readline() {
            log::info!("Event: {}", event);
        }
    }
}