/*
	vid_common_vulkan.c

	Common Vulkan video driver functions

	Copyright (C) 1996-1997 Id Software, Inc.
	Copyright (C) 2019      Bill Currie <bill@taniwha.org>

	This program is free software; you can redistribute it and/or
	modify it under the terms of the GNU General Public License
	as published by the Free Software Foundation; either version 2
	of the License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

	See the GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#ifdef HAVE_MATH_H
# include <math.h>
#endif
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif

#include "QF/cvar.h"
#include "QF/dstring.h"
#include "QF/input.h"
#include "QF/mathlib.h"
#include "QF/qargs.h"
#include "QF/quakefs.h"
#include "QF/sys.h"
#include "QF/va.h"
#include "QF/vid.h"
#include "QF/Vulkan/qf_vid.h"
#include "QF/Vulkan/device.h"
#include "QF/Vulkan/instance.h"
#include "QF/Vulkan/swapchain.h"

#include "compat.h"
#include "d_iface.h"
#include "r_internal.h"
#include "vid_vulkan.h"

#include "util.h"

cvar_t *vulkan_presentation_mode;

static void
vulkan_presentation_mode_f (cvar_t *var)
{
	if (!strcmp (var->string, "immediate")) {
		var->int_val = VK_PRESENT_MODE_IMMEDIATE_KHR;
	} else if (!strcmp (var->string, "fifo")) {
		var->int_val = VK_PRESENT_MODE_FIFO_KHR;
	} else if (!strcmp (var->string, "relaxed")) {
		var->int_val = VK_PRESENT_MODE_FIFO_RELAXED_KHR;
	} else if (!strcmp (var->string, "mailbox")) {
		var->int_val = VK_PRESENT_MODE_MAILBOX_KHR;
	} else {
		Sys_Printf ("Invalid presentation mode, using fifo\n");
		var->int_val = VK_PRESENT_MODE_FIFO_KHR;
	}
}

static void
Vulkan_Init_Cvars (void)
{
	vulkan_use_validation = Cvar_Get ("vulkan_use_validation", "1", CVAR_NONE,
									  0,
									  "enable LunarG Standard Validation "
									  "Layer if available (requires instance "
									  "restart).");
	// FIXME implement fallback choices (instead of just fifo)
	vulkan_presentation_mode = Cvar_Get ("vulkan_presentation_mode", "mailbox",
										 CVAR_NONE, vulkan_presentation_mode_f,
										 "desired presentation mode (may fall "
										 "back to fifo).");
}

static const char *instance_extensions[] = {
	VK_KHR_SURFACE_EXTENSION_NAME,
	0,
};

static const char *device_extensions[] = {
	VK_KHR_SWAPCHAIN_EXTENSION_NAME,
	0,
};

void
Vulkan_Init_Common (vulkan_ctx_t *ctx)
{
	Sys_Printf ("Vulkan_Init_Common\n");
	Vulkan_Init_Cvars ();

	ctx->instance = QFV_CreateInstance (ctx, PACKAGE_STRING, 0x000702ff, 0, instance_extensions);//FIXME version
}

void
Vulkan_Shutdown_Common (vulkan_ctx_t *ctx)
{
	if (ctx->swapchain) {
		QFV_DestroySwapchain (ctx->swapchain);
	}
	ctx->instance->funcs->vkDestroySurfaceKHR (ctx->instance->instance,
											   ctx->surface, 0);
	if (ctx->device) {
		QFV_DestroyDevice (ctx->device);
	}
	if (ctx->instance) {
		QFV_DestroyInstance (ctx->instance);
	}
	ctx->instance = 0;
	ctx->unload_vulkan (ctx);
}

void
Vulkan_CreateDevice (vulkan_ctx_t *ctx)
{
	ctx->device = QFV_CreateDevice (ctx, device_extensions);
}

void
Vulkan_CreateSwapchain (vulkan_ctx_t *ctx)
{
	VkSwapchainKHR old_swapchain = 0;
	if (ctx->swapchain) {
		old_swapchain = ctx->swapchain->swapchain;
		free (ctx->swapchain);
	}
	ctx->swapchain = QFV_CreateSwapchain (ctx, old_swapchain);
	if (ctx->swapchain->swapchain == old_swapchain) {
		ctx->device->funcs->vkDestroySwapchainKHR (ctx->device->dev,
												   old_swapchain, 0);
	}
}