#include <obs-module.h>
#include <util/windows/win-version.h>
#include <util/platform.h>
#include <util/dstr.h>
#include <util/config-file.h>
#include <util/pipe.h>

#include <windows.h>
#include "graphics-hook-info.h"

extern struct graphics_offsets offsets32;
extern struct graphics_offsets offsets64;

static inline bool load_offsets_from_string(struct graphics_offsets *offsets,
		const char *str)
{
	config_t *config;

	if (config_open_string(&config, str) != CONFIG_SUCCESS) {
		return false;
	}

	offsets->d3d8.present =
		(uint32_t)config_get_uint(config, "d3d8", "present");

	offsets->d3d9.present =
		(uint32_t)config_get_uint(config, "d3d9", "present");
	offsets->d3d9.present_ex =
		(uint32_t)config_get_uint(config, "d3d9", "present_ex");
	offsets->d3d9.present_swap =
		(uint32_t)config_get_uint(config, "d3d9", "present_swap");
	offsets->d3d9.d3d9_clsoff =
		(uint32_t)config_get_uint(config, "d3d9", "d3d9_clsoff");
	offsets->d3d9.is_d3d9ex_clsoff =
		(uint32_t)config_get_uint(config, "d3d9", "is_d3d9ex_clsoff");

	offsets->dxgi.present =
		(uint32_t)config_get_uint(config, "dxgi", "present");
	offsets->dxgi.present1 =
		(uint32_t)config_get_uint(config, "dxgi", "present1");
	offsets->dxgi.resize =
		(uint32_t)config_get_uint(config, "dxgi", "resize");

	config_close(config);
	return true;
}

static inline bool load_offsets_from_file(struct graphics_offsets *offsets,
		const char *file)
{
	char *str = os_quick_read_utf8_file(file);
	bool success = false;
	if (str && *str)
		success = load_offsets_from_string(offsets, str);
	bfree(str);
	return success;
}

static inline bool config_ver_mismatch(
		config_t *ver_config,
		const char *section,
		struct win_version_info *ver)
{
	struct win_version_info config_ver;
	bool mismatch = false;

#define get_sub_ver(subver) \
	config_ver.subver = (int)config_get_int(ver_config, section, #subver); \
	mismatch |= config_ver.subver != ver->subver;

	get_sub_ver(major);
	get_sub_ver(minor);
	get_sub_ver(build);
	get_sub_ver(revis);

#undef get_sub_ver

	return mismatch;
}

static inline void write_config_ver(config_t *ver_config, const char *section,
		struct win_version_info *ver)
{
#define set_sub_ver(subver) \
	config_set_int(ver_config, section, #subver, ver->subver);

	set_sub_ver(major);
	set_sub_ver(minor);
	set_sub_ver(build);
	set_sub_ver(revis);

#undef set_sub_ver
}

static bool get_32bit_system_dll_ver(const wchar_t *system_lib,
		struct win_version_info *ver)
{
	wchar_t path[MAX_PATH];
	UINT ret;

#ifdef _WIN64
	ret = GetSystemWow64DirectoryW(path, MAX_PATH);
#else
	ret = GetSystemDirectoryW(path, MAX_PATH);
#endif
	if (!ret) {
		blog(LOG_ERROR, "Failed to get windows 32bit system path: "
		                "%lu", GetLastError());
		return false;
	}

	wcscat(path, L"\\");
	wcscat(path, system_lib);
	return get_dll_ver(path, ver);
}

bool cached_versions_match(void)
{
	struct win_version_info d3d8_ver  = {0};
	struct win_version_info d3d9_ver  = {0};
	struct win_version_info dxgi_ver = {0};
	bool ver_mismatch = false;
	config_t *config;
	char *ver_file;
	int ret;

	ver_mismatch |= !get_32bit_system_dll_ver(L"d3d8.dll", &d3d8_ver);
	ver_mismatch |= !get_32bit_system_dll_ver(L"d3d9.dll", &d3d9_ver);
	ver_mismatch |= !get_32bit_system_dll_ver(L"dxgi.dll", &dxgi_ver);

	ver_file = obs_module_config_path("version.ini");
	if (!ver_file)
		return false;

	ret = config_open(&config, ver_file, CONFIG_OPEN_ALWAYS);
	if (ret != CONFIG_SUCCESS)
		goto failed;

	ver_mismatch |= config_ver_mismatch(config, "d3d8", &d3d8_ver);
	ver_mismatch |= config_ver_mismatch(config, "d3d9", &d3d9_ver);
	ver_mismatch |= config_ver_mismatch(config, "dxgi", &dxgi_ver);

	if (ver_mismatch) {
		write_config_ver(config, "d3d8", &d3d8_ver);
		write_config_ver(config, "d3d9", &d3d9_ver);
		write_config_ver(config, "dxgi", &dxgi_ver);
		config_save_safe(config, "tmp", NULL);
	}

failed:
	bfree(ver_file);
	config_close(config);
	return !ver_mismatch;
}

bool load_graphics_offsets(bool is32bit)
{
	char *offset_exe_path = NULL;
	struct dstr offset_exe = {0};
	char *config_ini = NULL;
	struct dstr str = {0};
	os_process_pipe_t *pp;
	bool success = false;
	char data[128];

#ifndef _WIN64
	if (!is32bit && !is_64_bit_windows()) {
		return true;
	}
#endif

	dstr_copy(&offset_exe, "get-graphics-offsets");
	dstr_cat(&offset_exe, is32bit ? "32.exe" : "64.exe");
	offset_exe_path = obs_module_file(offset_exe.array);

	pp = os_process_pipe_create(offset_exe_path, "r");
	if (!pp) {
		blog(LOG_INFO, "load_graphics_offsets: Failed to start '%s'",
				offset_exe.array);
		goto error;
	}

	for (;;) {
		size_t len = os_process_pipe_read(pp, (uint8_t*)data, 128);
		if (!len)
			break;

		dstr_ncat(&str, data, len);
	}

	config_ini = obs_module_config_path(is32bit ? "32.ini" : "64.ini");
	os_quick_write_utf8_file_safe(config_ini, str.array, str.len, false,
			"tmp", NULL);
	bfree(config_ini);

	success = load_offsets_from_string(is32bit ? &offsets32 : &offsets64,
			str.array);
	if (!success) {
		blog(LOG_INFO, "load_graphics_offsets: Failed to load string");
	}

	os_process_pipe_destroy(pp);

error:
	bfree(offset_exe_path);
	dstr_free(&offset_exe);
	dstr_free(&str);
	return success;
}

bool load_cached_graphics_offsets(bool is32bit)
{
	char *config_ini = NULL;
	bool success;

	config_ini = obs_module_config_path(is32bit ? "32.ini" : "64.ini");
	success = load_offsets_from_file(is32bit ? &offsets32 : &offsets64,
			config_ini);
	if (!success)
		success = load_graphics_offsets(is32bit);

	bfree(config_ini);
	return success;
}
