/*
 *	Copyright (c) 2024 Scott Duensing, scott@kangaroopunch.com
 *
 *	Permission is hereby granted, free of charge, to any person obtaining a copy
 *	of this software and associated documentation files (the "Software"), to deal
 *	in the Software without restriction, including without limitation the rights
 *	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 *	copies of the Software, and to permit persons to whom the Software is
 *	furnished to do so, subject to the following conditions:
 *
 *	The above copyright notice and this permission notice shall be included in
 *	all copies or substantial portions of the Software.
 *
 *	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 *	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 *	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 *	SOFTWARE.
 */


#ifndef WITHOUT_FILE


#include <string.h>

#ifndef F256LIB_AMALGAMATED_BUILD
#include "f_file.h"
#endif


#define MAX_DRIVES 8


static char _dirStream[MAX_DRIVES];


static bool     findName(char *name, int16_t *offset);
static int16_t  kernelRead(uint8_t fd, void *buf, uint16_t nbytes);
static int16_t  kernelWrite(uint8_t fd, void *buf, uint16_t nbytes);
static char    *pathWithoutDrive(char *path, byte *drive);


#pragma push_macro("close")
#undef close
int8_t fileClose(uint8_t *fd) {
	kernelArgs->file.close.stream = *fd;
	kernelCall(File.Close);

	free(fd);

	for (;;) {
		kernelNextEvent();
		switch (kernelEventData.type) {
			case kernelEvent(file.CLOSED):
			case kernelEvent(file.ERROR):
				return -1;
			default:
				continue;
		}
	}

	return 0;
}
#pragma pop_macro("close")


#pragma push_macro("close")
#undef close
int8_t fileCloseDir(char *dir) {
	if (!dir) return -1;

	for (;;) {
		if (*dir) {
			kernelArgs->directory.close.stream = *dir;
			kernelCall(Directory.Close);
			if (!kernelError) {
				*dir = 0;
			}
		}
		kernelNextEvent();
		if (kernelEventData.type == kernelEvent(directory.CLOSED)) {
			dir = NULL;
			return 0;
		}
	}
}
#pragma pop_macro("close")


int8_t fileMakeDir(char *dir) {
	byte  drive;

	dir = pathWithoutDrive(dir, &drive);

	kernelArgs->directory.mkdir.drive = drive;
	kernelArgs->common.buf = dir;
	kernelArgs->common.buflen = strlen(dir);
	kernelCall(Directory.MkDir);
	if (kernelError) return -1;

	for (;;) {
		kernelNextEvent();

		if (kernelEventData.type == kernelEvent(directory.CREATED)) break;
		if (kernelEventData.type == kernelEvent(directory.ERROR))   return -1;
	}

	return 0;
}


uint8_t *fileOpen(char *fname, char *mode) {
	uint8_t  ret = 0;
	uint8_t  m   = 0;  // Default to READ.
	uint8_t *fd;
	byte     drive;
	char    *c;

	fname = pathWithoutDrive(fname, &drive);

	c = mode;
	while (*c != 0) {
		if (*c == 'w') m = 1;  // WRITE
		if (*c == 'a') m = 2;  // APPEND
		c++;
	}

	kernelArgs->common.buf = (uint8_t *)fname;
	kernelArgs->common.buflen = strlen(fname);
	kernelArgs->file.open.drive = drive;
	kernelArgs->file.open.mode = m;
	ret = kernelCall(File.Open);
	if (kernelError) return NULL;

	for (;;) {
		kernelNextEvent();
		switch (kernelEventData.type) {
			case kernelEvent(file.OPENED):
				fd = (uint8_t *)malloc(sizeof(uint8_t));
				*fd = ret;
				return fd;
			case kernelEvent(file.NOT_FOUND):
			case kernelEvent(file.ERROR):
				return NULL;
			default:
				continue;
		}
	}
}


char *fileOpenDir(char *name) {
	byte  drive;
	char  stream;
	char *dir;

	name = pathWithoutDrive(name, &drive);

	if (_dirStream[drive]) return NULL;  // Only one at a time.

	kernelArgs->directory.open.drive = drive;
	kernelArgs->common.buf = name;
	kernelArgs->common.buflen = strlen(name);
	stream = kernelCall(Directory.Open);
	if (kernelError) return NULL;

	for (;;) {
		kernelNextEvent();

		if (kernelEventData.type == kernelEvent(directory.OPENED)) break;
		if (kernelEventData.type == kernelEvent(directory.ERROR))  return NULL;
	}

	_dirStream[drive] = stream;
	dir = &_dirStream[drive];

	return dir;
}


int16_t fileRead(void *buf, uint16_t nbytes, uint16_t nmemb, uint8_t *fd) {
	char    *data     = (char *)buf;
	int16_t  read     = 0;
	uint16_t bytes    = nbytes * nmemb;
	int16_t  returned;

	while (read < bytes) {
		returned = kernelRead(*fd, data + read, bytes - read);
		if (returned < 0) return -1;
		if (returned == 0) break;
		read += returned;
	}

	return read / nbytes;
}


#pragma push_macro("EOF")
#pragma push_macro("FILE")
#undef EOF
#undef FILE
fileDirEntT *fileReadDir(char *dir) {
	static fileDirEntT dirent;
	uint16_t len;

	if (!dir) return NULL;

	kernelArgs->directory.read.stream = *dir;
	kernelCall(Directory.Read);
	if (kernelError) return NULL;

	for (;;) {
		kernelNextEvent();

		switch (kernelEventData.type) {
			case kernelEvent(directory.VOLUME):
				dirent.d_blocks = 0;
				dirent.d_type = 2;
				break;

			case kernelEvent(directory.FILE):
				kernelArgs->common.buf = &dirent.d_blocks;
				kernelArgs->common.buflen = sizeof(dirent.d_blocks);
				kernelCall(ReadExt);
				dirent.d_type = (dirent.d_blocks == 0);
				break;

			case kernelEvent(directory.FREE):
				// dirent doesn't care about these types of records.
				kernelArgs->directory.read.stream = *dir;
				kernelCall(Directory.Read);
				if (!kernelError) continue;
				// Fall through.

			case kernelEvent(directory.EOF):
			case kernelEvent(directory.ERROR):
				return NULL;

			default:
				continue;
		}

		// Copy the name.
		len = kernelEventData.directory.file.len;
		if (len >= sizeof(dirent.d_name)) {
			len = sizeof(dirent.d_name) - 1;
		}

		if (len > 0) {
			kernelArgs->common.buf = &dirent.d_name;
			kernelArgs->common.buflen = len;
			kernelCall(ReadData);
		}
		dirent.d_name[len] = 0;

		return &dirent;
	}
}
#pragma pop_macro("FILE")
#pragma pop_macro("EOF")


int8_t fileRemoveDir(char *dir) {
	byte  drive;

	dir = pathWithoutDrive(dir, &drive);

	kernelArgs->directory.mkdir.drive = drive;
	kernelArgs->common.buf = dir;
	kernelArgs->common.buflen = strlen(dir);
	kernelCall(Directory.RmDir);
	if (kernelError) return -1;

	for (;;) {
		kernelNextEvent();

		if (kernelEventData.type == kernelEvent(directory.DELETED)) break;
		if (kernelEventData.type == kernelEvent(directory.ERROR))   return -1;
	}

	return 0;
}


int8_t fileRename(char *name, char *to) {
	byte    drive;
	byte    drive2;
	int16_t path1;
	int16_t path2;

	name = pathWithoutDrive(name, &drive);
	to = pathWithoutDrive(to, &drive2);

	// ensure that the paths match
	if (false
		|| (drive != drive2)
		|| !findName(name, &path1)
		|| !findName(to, &path2)
		|| (path1 != path2)
		|| (strncmp(name, to, path1) != 0)
		) {
		return -1;
	}

	to += path2;

	kernelArgs->file.delete.drive = drive;
	kernelArgs->common.buf = name;
	kernelArgs->common.buflen = strlen(name);
	kernelArgs->common.ext = to;
	kernelArgs->common.extlen = strlen(to);
	kernelCall(File.Rename);
	if (kernelError) return -1;

	for (;;) {
		kernelNextEvent();
		if (kernelEventData.type == kernelEvent(file.RENAMED)) break;
		if (kernelEventData.type == kernelEvent(file.ERROR))   return -1;
	}

	return 0;
}


void fileReset(void) {
	byte x;

	for (x=0; x<MAX_DRIVES; x++) _dirStream[x] = 0;
}


int8_t fileSeek(uint8_t *fd, uint32_t offset, uint8_t whence) {
	if (whence != SEEK_SET) return -1;

	//***TODO*** We should do this manually for IEC devices.

	kernelArgs->file.seek.stream = *fd;
	kernelArgs->file.seek.offset = offset;
	kernelCall(File.Seek);
	if (kernelError) return -1;

	return 0;
}


int8_t fileUnlink(char *name) {
	byte drive;

	name = pathWithoutDrive(name, &drive);
	kernelArgs->file.delete.drive = drive;
	kernelArgs->common.buf = name;
	kernelArgs->common.buflen = strlen(name);
	kernelCall(File.Delete);
	if (kernelError) return -1;

	for (;;) {
		kernelNextEvent();
		if (kernelEventData.type == kernelEvent(file.DELETED)) break;
		if (kernelEventData.type == kernelEvent(file.ERROR))   return -1;
	}

	return 0;
}


int16_t fileWrite(void *buf, uint16_t nbytes, uint16_t nmemb, uint8_t *fd) {
	uint8_t *data  = (uint8_t *)buf;
	int16_t  total = 0;
	int16_t  bytes = nbytes * nmemb;
	uint8_t  writing;
	int16_t  written;

	while (bytes) {

		if (bytes > 254) {
			writing = 254;
		} else {
			writing = bytes;
		}

		written = kernelWrite(*fd, data + total, writing);
		if (written <= 0) {
			return -1;
		}

		total += written;
		bytes -= written;
	}

	return total / nbytes;
}


static bool findName(char *name, int16_t *offset) {
	int16_t i;
	int16_t pos;

	for (i = pos = 0; name[i]; i++) {
		if (name[i] == '/') {
			pos = i+1;
			if (!name[pos]) {
				// No base name found!
				return false;
			}
		}
	}

	*offset = pos;
	return true;
}


#pragma push_macro("EOF")
#undef EOF
static int16_t kernelRead(uint8_t fd, void *buf, uint16_t nbytes) {

	// STDIN
	if (fd == 0) {
		*(char *)buf = getchar();
		return 1;
	}

	if (nbytes > 256) nbytes = 256;

	kernelArgs->file.read.stream = fd;
	kernelArgs->file.read.buflen = nbytes;
	kernelCall(File.Read);
	if (kernelError) return -1;

	for(;;) {
		kernelNextEvent();
		switch (kernelEventData.type) {
			case kernelEvent(file.DATA):
				kernelArgs->common.buf = buf;
				kernelArgs->common.buflen = kernelEventData.file.data.delivered;
				kernelCall(ReadData);
				if (!kernelEventData.file.data.delivered) return 256;
				return kernelEventData.file.data.delivered;
			case kernelEvent(file.EOF):
				return 0;
			case kernelEvent(file.ERROR):
				return -1;
			default:
				continue;
		}
	}
}
#pragma pop_macro("EOF")


static int16_t kernelWrite(uint8_t fd, void *buf, uint16_t nbytes) {
	int16_t  i;
	char    *text;

	// STDOUT
	if (fd == 1) {
		text = (char *)buf;
		for (i = 0; i < nbytes; i++) {
			__putchar(text[i]);
		}
		return i;
	}

	kernelArgs->file.read.stream = fd;
	kernelArgs->common.buf = buf;
	kernelArgs->common.buflen = nbytes;
	kernelCall(File.Write);
	if (kernelError) return -1;

	for (;;) {
		kernelNextEvent();
		if (kernelEventData.type == kernelEvent(file.WROTE)) return kernelEventData.file.data.delivered;
		if (kernelEventData.type == kernelEvent(file.ERROR)) return -1;
	}
}


static char *pathWithoutDrive(char *path, byte *drive) {
	*drive = 0;

	if (strlen(path) < 2) return path;
	if (path[1] != ':')   return path;
	if ((*path >= '0') && (*path <= '7')) *drive = *path - '0';

	return (path + 2);
}


#endif