#include <stdio.h>
#include <cstdint>
#include <vector>
#include <stdexcept>
// For reading FIFO
#include <fcntl.h>
#include <unistd.h>
// For sleep
#include <chrono>
#include <thread>

// Local files
#include "utility/bitmap.hpp"
#include "utility/buffer.hpp"
#include "signal_processing/fft.hpp"
#include "ergodox.hpp"
#include "commands.h"
#include "config.h"

#include "spdlog/spdlog.h"


// TODO:
//
// FFT:
//   stereo support (and maybe different bitrates?)
//   Optimization: don't copy filename in buffer?
//   understand consumption rate
//   understand BIN2HZ
//   understand values and sizes (DFT_TOTAL, DFT_NONZERO, etc)
//     note that wave and spectrum have different sizes
//   clear fft when not in use
//
//   MPD interface
//
// Keyboard interface:
//   Fix segfault
//   Clean up reconnect code
//   Better log messages, compiled spdlog
//
//   Get parameters from keyboard (width, height, etc)
//
// Later:
//   beat detection
//   waveform animation
//   pcm from pulse


const size_t width = 10;
const size_t height = BOTTOM_SKIP + KB_RESOLUTION + TOP_SKIP;


int main(int argc, char *argv[]) {

	spdlog::set_level(spdlog::level::info);

	// buffer size for waveform:
	// (44100 / fps * 10), make 10 bigger for slower scrolling
	//
	// Double both buffer sizes if stereo

	// FFT generator
	FFT_Visualizer fft = FFT_Visualizer(
		width, height, MIN_HZ, MAX_HZ
	);

	// Audio buffer
	Buffer buf = Buffer(
		"/tmp/mpd.fifo",
		44100 / 2, // Keep 500ms of data in buffer
		fft.compute_buffer_output_size()
	);

	// HID interface wrapper
	Ergodox Dox = Ergodox::init(
		HID_VENDOR_ID,
		HID_PRODUCT_ID,
		HID_USAGE,
		HID_USAGE_PAGE
	);

	// Write buffer
	uint8_t hid_buf[Dox.packet_size];

	Dox.connect_loop();


	// Frame rate limiter
	std::chrono::time_point<
		std::chrono::steady_clock,
		std::chrono::nanoseconds
	> t = std::chrono::steady_clock::now();
	//t += std::chrono::milliseconds(30);
	//this_thread::sleep_until(t);


	while (1) {

		if (Dox.is_connected()) {
			if (std::chrono::steady_clock::now() > t + std::chrono::milliseconds(30)) {
				if (Dox.get_animation_mode() == 0x02) {
					buf.update();
					fft.update(buf);

					hid_buf[0] = CMD_ANIM_DATA_fft;
					for (size_t i = 0; i < 10; i++) {
						// Get height from fft, apply bottom_skip
						ssize_t h = fft.get_output()[i] - BOTTOM_SKIP;

						// Enforce max and min
						// max implicitly enforces top_skip
						h = h>KB_RESOLUTION ? KB_RESOLUTION : h;
						h = h<0 ? 0 : h;

						hid_buf[i + 1] = h;
					}
				}

				Dox.write(CMD_ANIM_DATA, hid_buf, Dox.packet_size);

				t = std::chrono::steady_clock::now();
			}

			// Dox.write might detect that we've been disconnected,
			// and Dox.read will fail if we are.
			// This check prevents it from doing that, and instead jumps to reconnect.
			if (!Dox.is_connected()) { continue; }

			// Read a packet if there is a packet to read
			if (Dox.read()) {
				uint8_t cmd = Dox.read_buf[0];

				switch(cmd) {
					case CMD_SEND_STATE:
						break;
				}
			}
		} else {
			Dox.connect_loop();
		}
	}

	return 0;
}