apple2js/js/formats/prodos/directory.ts

139 lines
4.2 KiB
TypeScript

import {
dateToUint32,
readFileName,
writeFileName,
uint32ToDate,
} from './utils';
import { FileEntry, readEntries, writeEntries } from './file_entry';
import { STORAGE_TYPES, ACCESS_TYPES } from './constants';
import { byte, word } from 'js/types';
import { ProDOSVolume } from '.';
import { VDH } from './vdh';
export const DIRECTORY_OFFSETS = {
PREV: 0x00,
NEXT: 0x02,
STORAGE_TYPE: 0x04,
NAME_LENGTH: 0x04,
DIRECTORY_NAME: 0x05,
RESERVED_1: 0x14,
CREATION: 0x1c,
CASE_BITS: 0x20,
VERSION: 0x20,
MIN_VERSION: 0x21,
ACCESS: 0x22,
ENTRY_LENGTH: 0x23,
ENTRIES_PER_BLOCK: 0x24,
FILE_COUNT: 0x25,
PARENT: 0x27,
PARENT_ENTRY_NUMBER: 0x29,
PARENT_ENTRY_LENGTH: 0x2a,
} as const;
export class Directory {
blocks: Uint8Array[];
vdh: VDH;
prev: word = 0;
next: word = 0;
storageType: byte = STORAGE_TYPES.DIRECTORY;
name: string = 'Untitled';
creation: Date = new Date();
access: byte = ACCESS_TYPES.ALL;
entryLength = 0x27;
entriesPerBlock: byte = 23;
fileCount = 0;
parent: word = 0;
parentEntryLength: byte = 0;
parentEntryNumber: byte = 0;
entries: FileEntry[] = [];
constructor(
private volume: ProDOSVolume,
private fileEntry: FileEntry
) {
this.blocks = this.volume.blocks();
this.vdh = this.volume.vdh();
this.read();
}
read(fileEntry?: FileEntry) {
this.fileEntry = fileEntry ?? this.fileEntry;
const block = new DataView(
this.blocks[this.fileEntry.keyPointer].buffer
);
this.prev = block.getUint16(DIRECTORY_OFFSETS.PREV, true);
this.next = block.getUint16(DIRECTORY_OFFSETS.NEXT, true);
this.storageType = block.getUint8(DIRECTORY_OFFSETS.STORAGE_TYPE) >> 4;
const nameLength = block.getUint8(DIRECTORY_OFFSETS.NAME_LENGTH) & 0xf;
const caseBits = block.getUint8(DIRECTORY_OFFSETS.CASE_BITS);
this.name = readFileName(
block,
DIRECTORY_OFFSETS.DIRECTORY_NAME,
nameLength,
caseBits
);
this.creation = uint32ToDate(
block.getUint32(DIRECTORY_OFFSETS.CREATION, true)
);
this.access = block.getUint8(DIRECTORY_OFFSETS.ACCESS);
this.entryLength = block.getUint8(DIRECTORY_OFFSETS.ENTRY_LENGTH);
this.entriesPerBlock = block.getUint8(
DIRECTORY_OFFSETS.ENTRIES_PER_BLOCK
);
this.fileCount = block.getUint16(DIRECTORY_OFFSETS.FILE_COUNT, true);
this.parent = block.getUint16(DIRECTORY_OFFSETS.PARENT, true);
this.parentEntryNumber = block.getUint8(
DIRECTORY_OFFSETS.PARENT_ENTRY_NUMBER
);
this.parentEntryLength = block.getUint8(
DIRECTORY_OFFSETS.PARENT_ENTRY_LENGTH
);
this.entries = readEntries(this.volume, block, this);
}
write() {
const block = new DataView(
this.blocks[this.fileEntry.keyPointer].buffer
);
const nameLength = this.name.length & 0x0f;
block.setUint8(
DIRECTORY_OFFSETS.STORAGE_TYPE,
(this.storageType << 4) & nameLength
);
const caseBits = writeFileName(
block,
DIRECTORY_OFFSETS.DIRECTORY_NAME,
this.name
);
block.setUint32(
DIRECTORY_OFFSETS.CREATION,
dateToUint32(this.creation),
true
);
block.setUint16(DIRECTORY_OFFSETS.CASE_BITS, caseBits);
block.setUint8(DIRECTORY_OFFSETS.ACCESS, this.access);
block.setUint8(DIRECTORY_OFFSETS.ENTRY_LENGTH, this.entryLength);
block.setUint8(
DIRECTORY_OFFSETS.ENTRIES_PER_BLOCK,
this.entriesPerBlock
);
block.setUint16(DIRECTORY_OFFSETS.FILE_COUNT, this.fileCount, true);
block.setUint16(DIRECTORY_OFFSETS.PARENT, this.parent, true);
block.setUint8(
DIRECTORY_OFFSETS.PARENT_ENTRY_NUMBER,
this.parentEntryNumber
);
block.setUint8(
DIRECTORY_OFFSETS.PARENT_ENTRY_LENGTH,
this.parentEntryLength
);
writeEntries(this.volume, block, this.vdh);
}
}