apple2js/js/formats/prodos/directory.ts

94 lines
3.7 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();
}
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);
}
}