#include <cstdio>
#include <algorithm>

#include <xf86drm.h>
#include <xf86drmMode.h>
#include <drm_fourcc.h>

#include "kms++.h"
#include "utils/color.h"

#include "../test.h"

using namespace std;
using namespace kms;

static void draw_color_bar(Framebuffer& buf, int old_xpos, int xpos, int width);

static void main_loop(Card& card);

#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))

struct Output
{
	Connector* connector;
	Crtc* crtc;
	Framebuffer* fbs[2];

	int front_buf;
	int bar_xpos;
};

static void do_flip(Output* out);

int main()
{
	Card card;

	if (card.master() == false)
		printf("Not DRM master, modeset may fail\n");

	//card.print_short();

	vector<Output> outputs;

	for (auto conn : card.get_connectors())
	{
		if (conn->connected() == false)
			continue;

		auto mode = conn->get_default_mode();

		Crtc* crtc = conn->get_current_crtc();
		if (!crtc) {
			for (auto c : conn->get_possible_crtcs()) {
				if (find_if(outputs.begin(), outputs.end(), [c](Output o) { return o.crtc == c; }) == outputs.end()) {
					crtc = c;
					break;
				}
			}
		}

		if (!crtc) {
			printf("failed to find crtc\n");
			return -1;
		}

		auto fb1 = new Framebuffer(card, mode.hdisplay, mode.vdisplay, "XR24");
		auto fb2 = new Framebuffer(card, mode.hdisplay, mode.vdisplay, "XR24");

		printf("conn %u, crtc %u, fb1 %u, fb2 %u\n", conn->id(), crtc->id(), fb1->id(), fb2->id());

		Output output = { };
		output.connector = conn;
		output.crtc = crtc;
		output.fbs[0] = fb1;
		output.fbs[1] = fb2;
		outputs.push_back(output);
	}

	for(auto& out : outputs) {
		auto conn = out.connector;
		auto crtc = out.crtc;

		auto mode = conn->get_default_mode();
		int r = crtc->set_mode(conn, *out.fbs[0], mode);
		ASSERT(r == 0);
	}

	for(auto& out : outputs)
		do_flip(&out);

	main_loop(card);

	for(auto& out : outputs) {
		delete out.fbs[0];
		delete out.fbs[1];
	}
}

static void do_flip(Output* out)
{
	const int bar_width = 20;
	const int bar_speed = 8;

	auto crtc = out->crtc;
	auto fb = out->fbs[(out->front_buf + 1) % 2];

	ASSERT(crtc);
	ASSERT(fb);

	int current_xpos = out->bar_xpos;
	int old_xpos = (current_xpos + (fb->width() - bar_width - bar_speed)) % (fb->width() - bar_width);
	int new_xpos = (current_xpos + bar_speed) % (fb->width() - bar_width);

	draw_color_bar(*fb, old_xpos, new_xpos, bar_width);

	out->bar_xpos = new_xpos;

	auto& card = crtc->card();

	if (card.has_atomic()) {
		int r;

		AtomicReq ctx(card);

		// XXX
		//ctx.add(plane, card.get_prop("CRTC_X"), 50);
		//ctx.add(plane, card.get_prop("CRTC_Y"), 50);

		r = ctx.test();
		ASSERT(r == 0);

		r = ctx.commit();
		ASSERT(r == 0);
	} else {
		int r = drmModePageFlip(card.fd(), crtc->id(), fb->id(), DRM_MODE_PAGE_FLIP_EVENT, out);
		ASSERT(r == 0);
	}
}

static void page_flip_handler(int fd, unsigned int frame,
			      unsigned int sec, unsigned int usec,
			      void *data)
{
	//printf("flip event %d, %d, %u, %u, %p\n", fd, frame, sec, usec, data);

	auto out = (Output*)data;

	out->front_buf = (out->front_buf + 1) % 2;

	do_flip(out);
}


static void main_loop(Card& card)
{
	drmEventContext ev = {
		.version = DRM_EVENT_CONTEXT_VERSION,
		.vblank_handler = 0,
		.page_flip_handler = page_flip_handler,
	};

	fd_set fds;

	FD_ZERO(&fds);

	int fd = card.fd();

	printf("press enter to exit\n");

	while (true) {
		int r;

		FD_SET(0, &fds);
		FD_SET(fd, &fds);

		r = select(fd + 1, &fds, NULL, NULL, NULL);
		if (r < 0) {
			fprintf(stderr, "select() failed with %d: %m\n", errno);
			break;
		} else if (FD_ISSET(0, &fds)) {
			fprintf(stderr, "exit due to user-input\n");
			break;
		} else if (FD_ISSET(fd, &fds)) {
			drmHandleEvent(fd, &ev);
		}
	}
}


static const RGB colors32[] = {
	RGB(255, 255, 255),
	RGB(255, 0, 0),
	RGB(255, 255, 255),
	RGB(0, 255, 0),
	RGB(255, 255, 255),
	RGB(0, 0, 255),
	RGB(255, 255, 255),
	RGB(200, 200, 200),
	RGB(255, 255, 255),
	RGB(100, 100, 100),
	RGB(255, 255, 255),
	RGB(50, 50, 50),
};

static const uint16_t colors16[] = {
	colors32[0].rgb565(),
	colors32[1].rgb565(),
	colors32[2].rgb565(),
	colors32[3].rgb565(),
	colors32[4].rgb565(),
	colors32[5].rgb565(),
	colors32[6].rgb565(),
	colors32[7].rgb565(),
	colors32[8].rgb565(),
	colors32[9].rgb565(),
	colors32[10].rgb565(),
	colors32[11].rgb565(),
};

static void drm_draw_color_bar_rgb888(Framebuffer& buf, int old_xpos, int xpos, int width)
{
	for (unsigned y = 0; y < buf.height(); ++y) {
		RGB bcol = colors32[y * ARRAY_SIZE(colors32) / buf.height()];
		uint32_t *line = (uint32_t*)(buf.map(0) + buf.stride(0) * y);

		if (old_xpos >= 0) {
			for (int x = old_xpos; x < old_xpos + width; ++x)
				line[x] = 0;
		}

		for (int x = xpos; x < xpos + width; ++x)
			line[x] = bcol.raw;
	}
}

static void drm_draw_color_bar_rgb565(Framebuffer& buf, int old_xpos, int xpos, int width)
{
	static_assert(ARRAY_SIZE(colors32) == ARRAY_SIZE(colors16), "bad colors arrays");

	for (unsigned y = 0; y < buf.height(); ++y) {
		uint16_t bcol = colors16[y * ARRAY_SIZE(colors16) / buf.height()];
		uint16_t *line = (uint16_t*)(buf.map(0) + buf.stride(0) * y);

		if (old_xpos >= 0) {
			for (int x = old_xpos; x < old_xpos + width; ++x)
				line[x] = 0;
		}

		for (int x = xpos; x < xpos + width; ++x)
			line[x] = bcol;
	}
}

static void drm_draw_color_bar_semiplanar_yuv(Framebuffer& buf, int old_xpos, int xpos, int width)
{
	const uint8_t colors[] = {
		0xff,
		0x00,
		0xff,
		0x20,
		0xff,
		0x40,
		0xff,
		0x80,
		0xff,
	};

	for (unsigned y = 0; y < buf.height(); ++y) {
		unsigned int bcol = colors[y * ARRAY_SIZE(colors) / buf.height()];
		uint8_t *line = (uint8_t*)(buf.map(0) + buf.stride(0) * y);

		if (old_xpos >= 0) {
			for (int x = old_xpos; x < old_xpos + width; ++x)
				line[x] = 0;
		}

		for (int x = xpos; x < xpos + width; ++x)
			line[x] = bcol;
	}
}

static void draw_color_bar(Framebuffer& buf, int old_xpos, int xpos, int width)
{
	switch (buf.format()) {
	case DRM_FORMAT_NV12:
	case DRM_FORMAT_NV21:
		// XXX not right but gets something on the screen
		drm_draw_color_bar_semiplanar_yuv(buf, old_xpos, xpos, width);
		break;

	case DRM_FORMAT_YUYV:
	case DRM_FORMAT_UYVY:
		// XXX not right but gets something on the screen
		drm_draw_color_bar_rgb565(buf, old_xpos, xpos, width);
		break;

	case DRM_FORMAT_RGB565:
		drm_draw_color_bar_rgb565(buf, old_xpos, xpos, width);
		break;

	case DRM_FORMAT_XRGB8888:
		drm_draw_color_bar_rgb888(buf, old_xpos, xpos, width);
		break;

	default:
		ASSERT(false);
	}
}