// vim:fileencoding=utf-8:foldmethod=marker

#include "file_posix.h"
#include "../../../common/platform/platform.h"

#ifdef WAPP_PLATFORM_POSIX

#include "../file.h"
#include "../../cpath/cpath.h"
#include "../../../common/aliases/aliases.h"
#include "../../../base/array/array.h"
#include "../../../base/strings/str8/str8.h"

#ifdef WAPP_PLATFORM_APPLE
#define _FILE_OFFSET_BITS 64
#define lseek64 lseek
#endif // !WAPP_PLATFORM_APPLE

#define __USE_LARGEFILE64
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>

wapp_intern i32 file_flags[FILE_ACCESS_MODE_COUNT] = {
	[WAPP_ACCESS_READ]                       = O_RDONLY,
	[WAPP_ACCESS_WRITE]                      = O_WRONLY | O_CREAT,
	[WAPP_ACCESS_APPEND]                     = O_WRONLY | O_APPEND | O_CREAT,
	[WAPP_ACCESS_READ_EX]                    = O_RDWR,
	[WAPP_ACCESS_WRITE_EX]                   = O_RDWR | O_CREAT,
	[WAPP_ACCESS_APPEND_EX]                  = O_RDWR | O_APPEND | O_CREAT,
	[WAPP_ACCESS_WRITE_FAIL_ON_EXIST]        = O_WRONLY | O_CREAT | O_EXCL,
	[WAPP_ACCESS_WRITE_FAIL_ON_EXIST_EX]     = O_RDWR | O_CREAT | O_EXCL,
};

wapp_intern mode_t file_modes[FILE_ACCESS_MODE_COUNT] = {
	[WAPP_ACCESS_READ]                       = 0,
	[WAPP_ACCESS_WRITE]                      = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
	[WAPP_ACCESS_APPEND]                     = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
	[WAPP_ACCESS_READ_EX]                    = 0,
	[WAPP_ACCESS_WRITE_EX]                   = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
	[WAPP_ACCESS_APPEND_EX]                  = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
	[WAPP_ACCESS_WRITE_FAIL_ON_EXIST]        = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
	[WAPP_ACCESS_WRITE_FAIL_ON_EXIST_EX]     = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
};

wapp_intern i32 file_seek_origins[FILE_SEEK_ORIGIN_COUNT] = {
	[WAPP_SEEK_START]   = SEEK_SET,
	[WAPP_SEEK_CURRENT] = SEEK_CUR,
	[WAPP_SEEK_END]     = SEEK_END,
};

WFile *_file_open(const Allocator *allocator, Str8RO *filepath, FileAccessMode mode) {
	wapp_persist c8 tmp[WAPP_PATH_MAX] = {0};
	memset(tmp, 0, WAPP_PATH_MAX);
	memcpy(tmp, filepath->buf, filepath->size);

	i32 fd = open((const char *)tmp, file_flags[mode], file_modes[mode]);
	if (fd < 0) {
		return NULL;
	}

	WFile *output = wapp_mem_allocator_alloc(allocator, sizeof(WFile));
	if (output) {
		output->fd = fd;
	}

	return output;
}

i64 _file_seek(WFile *file, i64 offset, FileSeekOrigin origin) {
	return lseek64(file->fd, offset, file_seek_origins[origin]);
}

u64 _file_read(void *dst_buf, u64 byte_count, WFile *file, u64 file_length) {
	u64 copy_byte_count = file_length <= byte_count ? file_length : byte_count;

	i64 count = read(file->fd, dst_buf, copy_byte_count);
	if (count < 0) { return 0; }

	return count;
}

i64 _file_write(const void *src_buf, WFile *file, u64 byte_count) {
	return write(file->fd, src_buf, byte_count);
}

i32 _file_flush(WFile *file) {
	return fsync(file->fd);
}

i32 _file_close(WFile *file) {
	return close(file->fd);
}

i32 _file_rename(Str8RO *old_filepath, Str8RO *new_filepath) {
	wapp_persist c8 old_tmp[WAPP_PATH_MAX] = {0};
	wapp_persist c8 new_tmp[WAPP_PATH_MAX] = {0};
	memset(old_tmp, 0, WAPP_PATH_MAX);
	memcpy(old_tmp, old_filepath->buf, old_filepath->size);
	memset(new_tmp, 0, WAPP_PATH_MAX);
	memcpy(new_tmp, new_filepath->buf, new_filepath->size);

	i32 link_result = link((const char *)old_tmp, (const char *)new_tmp);
	if (link_result == 0) {
		_file_remove(old_filepath);
	}

	return link_result;
}

i32 _file_remove(Str8RO *filepath) {
	wapp_persist c8 tmp[WAPP_PATH_MAX] = {0};
	memset(tmp, 0, WAPP_PATH_MAX);
	memcpy(tmp, filepath->buf, filepath->size);

	return unlink((const char *)tmp);
}

#endif // !WAPP_PLATFORM_POSIX