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#pragma once
#include <Windows.h>
#include "util.hpp"

namespace winapi
{
	static uintptr_t get_procaddr_ex( HANDLE process, HMODULE mod, const char* proc ) {
		IMAGE_DOS_HEADER		dos_hdr;
		IMAGE_NT_HEADERS		nt_hdrs;
		IMAGE_EXPORT_DIRECTORY	export_dir;
		uintptr_t				export_addr;
		char					export_name[ 64 ];
		uintptr_t*				names;
		uintptr_t*				funcs;
		uint16_t*				ords;
		uintptr_t				ret{ };

		ReadProcessMemory( process, mod, &dos_hdr, sizeof( dos_hdr ), 0 );
		ReadProcessMemory( process, ( void* )( uintptr_t( mod ) + dos_hdr.e_lfanew ),
			&nt_hdrs, sizeof( nt_hdrs ), nullptr );

		export_addr = nt_hdrs.OptionalHeader.DataDirectory[ 0 ].VirtualAddress;
		ReadProcessMemory( process, ( void* )( uintptr_t( mod ) + export_addr ),
			&export_dir, sizeof( export_dir ), nullptr );

		if( !export_dir.NumberOfFunctions )
			return uintptr_t{ };
		
		funcs = ( uintptr_t* )( malloc( sizeof( uintptr_t ) * export_dir.AddressOfFunctions ) );
		names = ( uintptr_t* )( malloc( sizeof( uintptr_t ) * export_dir.NumberOfNames ) );
		ords  = ( uint16_t* ) ( malloc( sizeof( uint16_t ) * export_dir.NumberOfNames ) );

		ReadProcessMemory( process, ( void* )( uintptr_t( mod ) + export_dir.AddressOfFunctions ),
			funcs, sizeof( uintptr_t ) * export_dir.NumberOfFunctions, nullptr );
		ReadProcessMemory( process, ( void* )( uintptr_t( mod ) + export_dir.AddressOfNames ),
			names, sizeof( uintptr_t ) * export_dir.NumberOfNames, nullptr );
		ReadProcessMemory( process, ( void* )( uintptr_t( mod ) + export_dir.AddressOfNameOrdinals ),
			ords, sizeof( uint16_t ) * export_dir.NumberOfNames, nullptr );

		auto read_str = [ &process ]( char* buf, size_t size, uintptr_t addr ) {
			for( size_t i{ }; i < size; ++i ) {
				char _c;
				ReadProcessMemory( process, ( void* )( addr + i ), &_c, 1, 0 );
				buf[ i ] = _c;
				if( !_c ) break;
			}

			buf[ size - 1 ] = 0;
		};

		for( size_t i{ }; i < export_dir.NumberOfNames; ++i ) {
			read_str( export_name, 64, uintptr_t( mod ) + names[ i ] );

			if( !strcmp( export_name, proc ) )
				ret = uintptr_t( mod ) + funcs[ ords[ i ] ];
		}

		::free( funcs );
		::free( names );
		::free( ords );

		return ret;
	}
}