apple2js/js/intbasic/decompiler.ts

211 lines
4.4 KiB
TypeScript

import { byte, word } from 'js/types';
const LETTERS =
' ' +
' !"#$%&\'()*+,-./0123456789:;<=>?' +
'@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_' +
'`abcdefghijklmnopqrstuvwxyz{|}~ ';
const TOKENS: Record<byte, string> = {
0x00: 'HIMEM:',
0x01: '$01',
0x02: '_',
0x03: ':',
0x04: 'LOAD',
0x05: 'SAVE',
0x06: 'CON',
0x07: 'RUN',
0x08: 'RUN',
0x09: 'DEL',
0x0a: ',',
0x0b: 'NEW',
0x0c: 'CLR',
0x0d: 'AUTO',
0x0e: ',',
0x0f: 'MAN',
0x10: 'HIMEM:',
0x11: 'LOMEM:',
0x12: '+',
0x13: '-',
0x14: '*',
0x15: '/',
0x16: '=',
0x17: '#',
0x18: '>=',
0x19: '>',
0x1a: '<=',
0x1b: '<>',
0x1c: '<',
0x1d: 'AND',
0x1e: 'OR',
0x1f: 'MOD',
0x20: '^',
0x21: '+',
0x22: '(',
0x23: ',',
0x24: 'THEN',
0x25: 'THEN',
0x26: ',',
0x27: ',',
0x28: '"',
0x29: '"',
0x2a: '(',
0x2b: '!',
0x2c: '!',
0x2d: '(',
0x2e: 'PEEK',
0x2f: 'RND',
0x30: 'SGN',
0x31: 'ABS',
0x32: 'PDL',
0x33: 'RNDX',
0x34: '(',
0x35: '+',
0x36: '-',
0x37: 'NOT',
0x38: '(',
0x39: '=',
0x3a: '#',
0x3b: 'LEN(',
0x3c: 'ASC(',
0x3d: 'SCRN(',
0x3e: ',',
0x3f: '(',
0x40: '$',
0x41: '$',
0x42: '(',
0x43: ',',
0x44: ',',
0x45: ';',
0x46: ';',
0x47: ';',
0x48: ',',
0x49: ',',
0x4a: ',',
0x4b: 'TEXT',
0x4c: 'GR',
0x4d: 'CALL',
0x4e: 'DIM',
0x4f: 'DIM',
0x50: 'TAB',
0x51: 'END',
0x52: 'INPUT',
0x53: 'INPUT',
0x54: 'INPUT',
0x55: 'FOR',
0x56: '=',
0x57: 'TO',
0x58: 'STEP',
0x59: 'NEXT',
0x5a: ',',
0x5b: 'RETURN',
0x5c: 'GOSUB',
0x5d: 'REM',
0x5e: 'LET',
0x5f: 'GOTO',
0x60: 'IF',
0x61: 'PRINT',
0x62: 'PRINT',
0x63: 'PRINT',
0x64: 'POKE',
0x65: ',',
0x66: 'COLOR=',
0x67: 'PLOT',
0x68: ',',
0x69: 'HLIN',
0x6a: ',',
0x6b: 'AT',
0x6c: 'VLIN',
0x6d: ',',
0x6e: 'AT',
0x6f: 'VTAB',
0x70: '=',
0x71: '=',
0x72: ')',
0x73: ')',
0x74: 'LIST',
0x75: ',',
0x76: 'LIST',
0x77: 'POP',
0x78: 'NODSP',
0x79: 'NODSP',
0x7a: 'NOTRACE',
0x7b: 'DSP',
0x7c: 'DSP',
0x7d: 'TRACE',
0x7e: 'PR#',
0x7f: 'IN#',
};
export default class IntBasicDump {
constructor(private data: Uint8Array) {}
private readByte(addr: word) {
return this.data[addr];
}
private readWord(addr: word) {
const lsb = this.readByte(addr);
const msb = this.readByte(addr + 1);
return (msb << 8) | lsb;
}
toString() {
let str = '';
let addr = 0;
const himem = this.data.length;
do {
let inRem = false;
let inQuote = false;
let isAlphaNum = false;
/* const length = */ this.readByte(addr++);
const lineno = this.readWord(addr);
addr += 2;
str += lineno;
str += ' ';
let val = 0;
do {
val = this.readByte(addr++);
if (
!inRem &&
!inQuote &&
!isAlphaNum &&
val >= 0xb0 &&
val <= 0xb9
) {
str += this.readWord(addr);
addr += 2;
} else if (val < 0x80 && val > 0x01) {
const t = TOKENS[val];
if (t.length > 1) {
str += ' ';
}
str += t;
if (t.length > 1) {
str += ' ';
}
if (val === 0x28) {
inQuote = true;
}
if (val === 0x29) {
inQuote = false;
}
if (val === 0x5d) {
inRem = true;
}
isAlphaNum = false;
} else if (val > 0x80) {
const char = LETTERS[val - 0x80];
str += char;
isAlphaNum = /[A-Z0-9]/.test(char);
}
} while (val !== 0x01);
str += '\n';
} while (addr < himem);
return str;
}
}