#!/usr/bin/env perl
## Copyright (C) 2008, 2009 by Daniel Friesel <derf@derf.homelinux.org>
##
## Permission to use, copy, modify, and/or distribute this software for any
## purpose with or without fee is hereby granted, provided that the above
## copyright notice and this permission notice appear in all copies.
##
## THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
## WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
## MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
## ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
## WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
## ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
## OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

use strict;
use warnings;
use utf8;
use 5.010;
use Getopt::Std;

binmode(STDOUT, ':utf8');
my $headerlength = 0x4a;
my $footerlength = 2;
my ($header, $footer);
my ($char, $char2);
my $out;
my $cache;
my $file;
my ($indent, $rindent) = (0,0);
my %opts;
my ($program, $length, $offset);
my %header;
my %all = (
	0x01 => '►DMS',
	0x02 => '►Dec',
	0x03 => '►Frac',
	0x04 => '→',
	0x05 => 'Boxplot',
	0x06 => '[',
	0x07 => ']',
	0x08 => '{',
	0x09 => '}',
	0x0a => 'r',
	0x0b => '°',
	0x0c => '⁻¹',
	0x0d => '²',
	0x0e => 'Ṭ',
	0x0f => '³',
	0x10 => '(',
	0x11 => ')',
	0x12 => 'round(',
	0x13 => 'pxl-Test(',
	0x14 => 'augment(',
	0x15 => 'rowSwap(',
	0x16 => 'row+(',
	0x17 => '*row(',
	0x18 => '*row+(',
	0x19 => 'max(',
	0x1a => 'min(',
	0x1b => 'R►Pr(',
	0x1c => 'R►Pθ(',
	0x1d => 'P►Rx(',
	0x1e => 'P►Ry',
	0x1f => 'median(',
	0x20 => 'randM(',
	0x21 => 'mean(',
	0x22 => 'solve(',
	0x23 => 'seq(',
	0x24 => 'fnInt(',
	0x25 => 'nDeriv(',
	0x27 => 'fMin(',
	0x28 => 'fMax(',
	0x29 => ' ',
	0x2a => '"',
	0x2b => ',',
	0x2c => 'i',
	0x2d => '!',
	0x2e => 'CubicReg',
	0x2f => 'QuartReg',
	0x30 => 0,
	0x31 => 1,
	0x32 => 2,
	0x33 => 3,
	0x34 => 4,
	0x35 => 5,
	0x36 => 6,
	0x37 => 7,
	0x38 => 8,
	0x39 => 9,
	0x3a => '.',
	0x3b => 'E',
	0x3c => ' or ',
	0x3d => ' xor ',
	0x3e => ':',
	0x3f => "\n",
	0x40 => ' and ',
	0x41 => 'A',
	0x42 => 'B',
	0x43 => 'C',
	0x44 => 'D',
	0x45 => 'E',
	0x46 => 'F',
	0x47 => 'G',
	0x48 => 'H',
	0x49 => 'I',
	0x4a => 'J',
	0x4b => 'K',
	0x4c => 'L',
	0x4d => 'M',
	0x4e => 'N',
	0x4f => 'O',
	0x50 => 'P',
	0x51 => 'O',
	0x52 => 'R',
	0x53 => 'S',
	0x54 => 'T',
	0x55 => 'U',
	0x56 => 'V',
	0x57 => 'W',
	0x58 => 'X',
	0x59 => 'Y',
	0x5a => 'Z',
	0x5b => 'θ',
	0x5f => 'prgm',
	0x64 => 'Radian',
	0x65 => 'Degree',
	0x66 => 'Normal',
	0x67 => 'Sci',
	0x68 => 'Eng',
	0x69 => 'Float',
	0x6a => '=',
	0x6b => '<',
	0x6c => '>',
	0x6d => '≤',
	0x6e => '≥',
	0x6f => '≠',
	0x70 => '+',
	0x71 => '-',
	0x72 => 'Ans',
	0x73 => 'Fix',
	0x74 => 'Horiz',
	0x75 => 'Full',
	0x76 => 'Func',
	0x77 => 'Param',
	0x78 => 'Polar',
	0x79 => 'Seq',
	0x7a => 'IndpntAuto',
	0x7b => 'IndpntAsk',
	0x7c => 'DependAuto',
	0x7d => 'DependAsk',
	0x7f => '☐',
	0x80 => '+',
	0x81 => '·',
	0x82 => '*',
	0x83 => '/',
	0x84 => 'Trace',
	0x85 => 'ClrDraw',
	0x86 => 'ZStandard',
	0x87 => 'ZTrig',
	0x88 => 'ZBox',
	0x89 => 'Zoom In',
	0x8a => 'Zoom Out',
	0x8b => 'ZSquare',
	0x8c => 'ZInteger',
	0x8d => 'ZPrevious',
	0x8e => 'ZDecimal',
	0x8f => 'ZoomStat',
	0x90 => 'ZoomRcl',
	0x91 => 'PrintScreen',
	0x92 => 'ZoomSto',
	0x93 => 'Text(',
	0x94 => 'nPr',
	0x95 => 'nCr',
	0x96 => 'FnOn',
	0x97 => 'FnOff',
	0x98 => 'StorePic',
	0x99 => 'RecallPic',
	0x9a => 'StoreGDB',
	0x9b => 'RecallGDB',
	0x9c => 'Line(',
	0x9d => 'Vertical',
	0x9e => 'Pt-On(',
	0x9f => 'Pt-Off(',
	0xa0 => 'Pt-Change(',
	0xa1 => 'Pxl-On(',
	0xa2 => 'Pxl-Off(',
	0xa3 => 'Pxl-Change(',
	0xa4 => 'Shade(',
	0xa5 => 'Circle(',
	0xa6 => 'Horizontal',
	0xa7 => 'Tangent(',
	0xa8 => 'DrawInv',
	0xa9 => 'DrawF',
	0xab => 'rand',
	0xac => 'π',
	0xad => 'getKey',
	0xae => '\'',
	0xaf => '?',
	0xb0 => '-',
	0xb1 => 'int(',
	0xb2 => 'abs(',
	0xb3 => 'det(',
	0xb4 => 'identity(',
	0xb5 => 'dim(',
	0xb6 => 'sum(',
	0xb7 => 'prod(',
	0xb8 => 'not(',
	0xb9 => 'iPart(',
	0xba => 'fPart(',
	0xbc => '√(',
	0xbd => '³√(',
	0xbe => 'ln(',
	0xbf => 'e^(',
	0xc0 => 'log(',
	0xc1 => '10^(',
	0xc2 => 'sin(',
	0xc3 => 'sinֿ¹(',
	0xc4 => 'cos(',
	0xc5 => 'cosֿ¹(',
	0xc6 => 'tan(',
	0xc7 => 'tanֿ¹(',
	0xc8 => 'sinh(',
	0xc9 => 'sinhֿ¹(',
	0xca => 'cosh(',
	0xcb => 'coshֿ¹(',
	0xcc => 'tanh(',
	0xcd => 'tanhֿ¹(',
	0xce => 'If ',
	0xcf => 'Then',
	0xd0 => 'Else',
	0xd1 => 'While ',
	0xd2 => 'Repeat ',
	0xd3 => 'For(',
	0xd4 => 'End',
	0xd5 => 'Return',
	0xd6 => 'Lbl ',
	0xd7 => 'Goto ',
	0xd8 => 'Pause',
	0xd9 => 'Stop',
	0xda => 'IS>(',
	0xdb => 'DS<(',
	0xdc => 'Input ',
	0xdd => 'Prompt ',
	0xde => 'Disp ',
	0xdf => 'DispGraph',
	0xe0 => 'Output(',
	0xe1 => 'ClrHome',
	0xe2 => 'Fill(',
	0xe3 => 'SortA(',
	0xe4 => 'SortD(',
	0xe5 => 'DispTable',
	0xe6 => 'Menu(',
	0xe7 => 'Send(',
	0xe8 => 'Get(',
	0xe9 => 'PlotsOn',
	0xea => 'PlotsOff',
	0xeb => '∟',
	0xec => 'Plot1(',
	0xed => 'Plot2(',
	0xee => 'Plot3(',
	0xf0 => '^',
	0xf1 => '×√',
	0xf2 => '1-Var Stats',
	0xf3 => '2-Var Stats',
	0xf4 => 'Linreg(a+bx)',
	0xf5 => 'ExpReg',
	0xf6 => 'LnReg',
	0xf7 => 'PwrReg',
	0xf8 => 'Med-Med',
	0xf9 => 'QuadReg',
	0xfa => 'ClrList',
	0xfb => 'ClrTable',
	0xfc => 'Histogram',
	0xfd => 'xyLine',
	0xfe => 'Scatter',
	0xff => 'LinReg(ax+b)',
);
my $special = {
	0x5c => {
		0x00 => '[A]',
		0x01 => '[B]',
		0x02 => '[C]',
		0x03 => '[D]',
		0x04 => '[E]',
		0x05 => '[F]',
		0x06 => '[G]',
		0x07 => '[H]',
		0x08 => '[I]',
		0x09 => '[J]',
	},
	0x5d => {
		0x00 => 'L₁',
		0x01 => 'L₂',
		0x02 => 'L₃',
		0x03 => 'L₄',
		0x04 => 'L₅',
		0x05 => 'L₆',
	},
	0x5e => {
		0x10 => 'Y₁',
		0x11 => 'Y₂',
		0x12 => 'Y₃',
		0x13 => 'Y₄',
		0x14 => 'Y₅',
		0x15 => 'Y₆',
		0x16 => 'Y₇',
		0x17 => 'Y₈',
		0x18 => 'Y₉',
		0x19 => 'Y₀',
		0x20 => 'X₁T',
		0x21 => 'Y₁T',
		0x22 => 'X₂T',
		0x23 => 'Y₂T',
		0x24 => 'X₃T',
		0x25 => 'Y₃T',
		0x26 => 'X₄T',
		0x27 => 'Y₄T',
		0x28 => 'X₅T',
		0x29 => 'Y₅T',
		0x2A => 'X₆T',
		0x2B => 'Y₆T',
		0x40 => 'r₁',
		0x41 => 'r₂',
		0x42 => 'r₃',
		0x43 => 'r₄',
		0x44 => 'r₅',
		0x45 => 'r₆',
		0x80 => 'u',
		0x81 => 'v',
		0x82 => 'w',
	},
	0x60 => {
		0x00 => 'Pic1',
		0x01 => 'Pic2',
		0x02 => 'Pic3',
		0x03 => 'Pic4',
		0x04 => 'Pic5',
		0x05 => 'Pic6',
		0x06 => 'Pic7',
		0x07 => 'Pic8',
		0x08 => 'Pic9',
		0x09 => 'Pic0',
	},
	0x61 => {
		0x00 => 'GDB1',
		0x01 => 'GDB2',
		0x02 => 'GDB3',
		0x03 => 'GDB4',
		0x04 => 'GDB5',
		0x05 => 'GDB6',
		0x06 => 'GDB7',
		0x07 => 'GDB8',
		0x08 => 'GDB9',
		0x09 => 'GDB0',
	},
	0x62 => {
		0x01 => 'RegEq',
		0x02 => 'n',
		0x03 => 'x̅',
		0x04 => 'Σx',
		0x05 => 'Σx²',
		0x06 => 'Sx',
		0x07 => 'σx',
		0x08 => 'minX',
		0x09 => 'maxX',
		0x0a => 'minY',
		0x0b => 'maxY',
		0x0c => 'y̅',
		0x0d => 'Σy',
		0x0e => 'Σy²',
		0x0f => 'Sy',
		0x10 => 'σy',
		0x11 => 'Σxy',
		0x12 => 'r',
		0x13 => 'Med',
		0x14 => 'Q1',
		0x15 => 'Q3',
		0x16 => 'a',
		0x17 => 'b',
		0x18 => 'c',
		0x19 => 'd',
		0x1a => 'e',
		0x1b => 'x₁',
		0x1c => 'x₂',
		0x1d => 'x₃',
		0x1e => 'y₁',
		0x1f => 'y₂',
		0x20 => 'y₃',
		0x21 => 'n',
		0x22 => 'p',
		0x23 => 'z',
		0x24 => 't',
		0x25 => 'χ²',
		0x26 => 'F',
		0x27 => 'df',
		0x28 => 'p̂',
		0x29 => 'p̂₁',
		0x2a => 'p̂₂',
		0x2b => 'x̅₁',
		0x2c => 'Sx₁',
		0x2d => 'n₁',
		0x2e => 'x̅₂',
		0x2f => 'Sx₂',
		0x30 => 'n₂',
		0x31 => 'Sxp',
		0x32 => 'lower',
		0x33 => 'upper',
		0x34 => 's',
		0x35 => 'r²',
		0x36 => 'R²',
		0x37 => 'Factor df',
		0x38 => 'Factor SS',
		0x39 => 'Factor MS',
		0x3a => 'Error df',
		0x3b => 'Error SS',
		0x3c => 'Error MS',
	},
	0x63 => {
		0x00 => 'ZXscl',
		0x01 => 'ZYscl',
		0x02 => 'Xscl',
		0x03 => 'Yscl',
		0x04 => 'u(nMin)',
		0x05 => 'v(nMin)',
		0x06 => 'u(n-1)',
		0x07 => 'v(n-1)',
		0x08 => 'Zu(nMin)',
		0x09 => 'Zv(nMin)',
		0x0a => 'Xmin',
		0x0b => 'Xmax',
		0x0c => 'Ymin',
		0x0d => 'Ymax',
		0x0e => 'Tmin',
		0x0f => 'Tmax',
		0x10 => 'θmin',
		0x11 => 'θmax',
		0x12 => 'ZXmin',
		0x13 => 'ZXmax',
		0x14 => 'ZYmin',
		0x15 => 'ZYmax',
		0x16 => 'Zθmin',
		0x17 => 'Zθmax',
		0x18 => 'ZTmin',
		0x19 => 'ZTmax',
		0x1a => 'TblStart',
		0x1b => 'PlotStart',
		0x1c => 'ZPlotStart',
		0x1d => 'nMax',
		0x1e => 'ZnMax',
		0x1f => 'nMin',
		0x20 => 'ZnMin',
		0x21 => 'ΔTbl',
		0x22 => 'Tstep',
		0x23 => 'θstep',
		0x24 => 'ZTstep',
		0x25 => 'Zθstep',
		0x26 => 'ΔX',
		0x27 => 'ΔY',
		0x28 => 'XFact',
		0x29 => 'YFact',
		0x2a => 'TblInput',
		0x2b => 'N',
		0x2c => 'I%',
		0x2d => 'PV',
		0x2e => 'PMT',
		0x2f => 'FV',
		0x30 => 'P/Y',
		0x31 => 'C/Y',
		0x32 => 'w(nMin)',
		0x33 => 'Zw(nMin)',
		0x34 => 'PlotStep',
		0x35 => 'ZPlotStep',
		0x36 => 'Xres',
		0x37 => 'ZXres',
	},
	0x7e => {
		0x00 => 'Sequential',
		0x01 => 'Simul',
		0x02 => 'PolarGC',
		0x03 => 'RectGC',
		0x04 => 'CoordOn',
		0x05 => 'CoordOff',
		0x06 => 'Connected',
		0x07 => 'Dot',
		0x08 => 'AxesOn',
		0x09 => 'AxesOff',
		0x0a => 'GridOn',
		0x0b => 'Gridoff',
		0x0c => 'LabelOn',
		0x0d => 'LabelOff',
		0x0e => 'Web',
		0x0f => 'Time',
		0x10 => 'uvAxes',
		0x11 => 'vwAxes',
		0x12 => 'uwAxes',
	},
	0xaa => {
		0x00 => 'Str1',
		0x01 => 'Str2',
		0x02 => 'Str3',
		0x03 => 'Str4',
		0x04 => 'Str5',
		0x05 => 'Str6',
		0x06 => 'Str7',
		0x07 => 'Str8',
		0x08 => 'Str9',
		0x09 => 'Str0',
	},
	0xbb => {
		0x00 => 'npv(',
		0x01 => 'irr(,',
		0x02 => 'bal(',
		0x03 => 'Σprn(',
		0x04 => 'ΣInt(',
		0x05 => '►Nom(',
		0x06 => '►Eff(',
		0x07 => 'dbd(',
		0x08 => 'lcm(',
		0x09 => 'gcd(',
		0x0A => 'randInt(',
		0x0B => 'randBin(',
		0x0C => 'sub(',
		0x0D => 'stdDev(',
		0x0E => 'variance(',
		0x0F => 'inString(',
		0x10 => 'normalcdf(',
		0x11 => 'invNorm(',
		0x12 => 'tcdf(',
		0x13 => 'χ²cdf(',
		0x14 => 'Fcdf(',
		0x15 => 'binompdf(',
		0x16 => 'binomcdf(',
		0x17 => 'poissonpdf(',
		0x18 => 'poissoncdf(',
		0x19 => 'geometpdf(',
		0x1A => 'geometcdf(',
		0x1B => 'normalpdf(',
		0x1C => 'tpdf(',
		0x1D => 'χ²pdf(',
		0x1E => 'Fpdf(',
		0x1F => 'randNorm(',
		0x20 => 'tmv_Pmt',
		0x21 => 'tmv_I%',
		0x22 => 'tmv_PV',
		0x23 => 'tmv_N',
		0x24 => 'tmv_FV',
		0x25 => 'conj(',
		0x26 => 'real(',
		0x27 => 'imag(',
		0x28 => 'angle(',
		0x29 => 'cumSum(',
		0x2A => 'expr(',
		0x2B => 'length(',
		0x2C => 'ΔList(',
		0x2D => 'ref(',
		0x2E => 'rref(',
		0x2F => '►Rect',
		0x30 => '►Polar',
		0x31 => 'e',
		0x32 => 'SinReg',
		0x33 => 'Logistic',
		0x34 => 'LinRegTTest',
		0x35 => 'ShadeNorm(',
		0x36 => 'Shade_t(',
		0x37 => 'Shadeχ²',
		0x38 => 'ShadeF(',
		0x39 => 'Matr►list(',
		0x3A => 'List►matr(',
		0x3B => 'Z-Test(',
		0x3C => 'T-Test',
		0x3D => '2-SampZTest(',
		0x3E => '1-PropZTest(',
		0x3F => '2-PropZTest(',
		0x40 => 'χ²-Test(',
		0x41 => 'ZInterval',
		0x42 => '2-SampZInt(',
		0x43 => '1-PropZInt(',
		0x44 => '2-PropZInt(',
		0x45 => 'GraphStyle(',
		0x46 => '2-SampTTest',
		0x47 => '2-SampFTest',
		0x48 => 'TInterval',
		0x49 => '2-SampTInt',
		0x4A => 'SetUpEditor',
		0x4B => 'Pmt_End',
		0x4C => 'Pmt_Bgn',
		0x4D => 'Real',
		0x4E => 're^θi',
		0x4F => 'a+bi',
		0x50 => 'ExprOn',
		0x51 => 'ExprOff',
		0x52 => 'ClrAllLists',
		0x53 => 'GetCalc(',
		0x54 => 'DelVar ',
		0x55 => 'Equ►String(',
		0x56 => 'String►Equ(',
		0x57 => 'Clear Entries',
		0x58 => 'Select(',
		0x59 => 'ANOVA(',
		0x5A => 'ModBoxplot',
		0x5B => 'NormProbPlot',
		0x64 => 'G-T',
		0x65 => 'ZoomFit',
		0x66 => 'DiagnosticOn',
		0x67 => 'DiagnosticOff',
		0x68 => 'Archive',
		0x69 => 'UnArchive',
		0x6A => 'Asm(',
		0x6B => 'AsmComp(',
		0x6C => 'AsmPrgm',
		0x6D => 'compiled asm',
		0x6E => 'Á',
		0x6F => 'À',
		0x70 => 'Â',
		0x71 => 'Ä',
		0x72 => 'á',
		0x73 => 'à',
		0x74 => 'â',
		0x75 => 'ä',
		0x76 => 'É',
		0x77 => 'È',
		0x78 => 'Ê',
		0x79 => 'Ë',
		0x7A => 'é',
		0x7B => 'è',
		0x7C => 'ê',
		0x7D => 'ë',
		0x7F => 'Ì',
		0x80 => 'Î',
		0x81 => 'Ï',
		0x82 => 'í',
		0x83 => 'ì',
		0x84 => 'î',
		0x85 => 'ï',
		0x86 => 'Ó',
		0x87 => 'Ò',
		0x88 => 'Ô',
		0x89 => 'Ö',
		0x8A => 'ó',
		0x8B => 'ò',
		0x8C => 'ô',
		0x8D => 'ö',
		0x8E => 'Ú',
		0x8F => 'Ù',
		0x90 => 'Û',
		0x91 => 'Ü',
		0x92 => 'ú',
		0x93 => 'ù',
		0x94 => 'û',
		0x95 => 'ü',
		0x96 => 'Ç',
		0x97 => 'ç',
		0x98 => 'Ñ',
		0x99 => 'ñ',
		0x9A => '´',
		0x9B => '`',
		0x9C => '¨',
		0x9D => '¿',
		0x9E => '¡',
		0x9F => 'α',
		0xA0 => 'β',
		0xA1 => 'γ',
		0xA2 => 'Δ',
		0xA3 => 'δ',
		0xA4 => 'ε',
		0xA5 => 'λ',
		0xA6 => 'μ',
		0xA7 => 'π',
		0xA8 => 'ρ',
		0xA9 => 'Σ',
		0xAB => 'φ',
		0xAC => 'Ω',
		0xAD => '^p',
		0xAE => 'χ',
		0xAF => 'F',
		0xB0 => 'a',
		0xB1 => 'b',
		0xB2 => 'c',
		0xB3 => 'd',
		0xB4 => 'e',
		0xB5 => 'f',
		0xB6 => 'g',
		0xB7 => 'h',
		0xB8 => 'i',
		0xB9 => 'j',
		0xBA => 'k',
		0xBC => 'l',
		0xBD => 'm',
		0xBE => 'n',
		0xBF => 'o',
		0xC0 => 'p',
		0xC1 => 'q',
		0xC2 => 'r',
		0xC3 => 's',
		0xC4 => 't',
		0xC5 => 'u',
		0xC6 => 'v',
		0xC7 => 'w',
		0xC8 => 'x',
		0xC9 => 'y',
		0xCA => 'z',
		0xCB => 'σ',
		0xCC => 'τ',
		0xCD => 'Í',
		0xCE => 'GarbageCollect',
		0xCF => '~',
		0xD1 => '@',
		0xD2 => '#',
		0xD3 => '$',
		0xD4 => '&',
		0xD5 => '`',
		0xD6 => ';',
		0xD7 => '\\',
		0xD8 => '|',
		0xD9 => '_',
		0xDA => '%',
		0xDB => '…',
		0xDC => '∠',
		0xDD => 'ß',
		0xDE => 'x',
		0xDF => 'T',
		0xE0 => '0',
		0xE1 => '1',
		0xE2 => '2',
		0xE3 => '3',
		0xE4 => '4',
		0xE5 => '5',
		0xE6 => '6',
		0xE7 => '7',
		0xE8 => '8',
		0xE9 => '9',
		0xEA => '10',
		0xEB => '←',
		0xEC => '→',
		0xED => '↑',
		0xEE => '↓',
		0xF0 => 'x',
		0xF1 => '∫',
		0xF4 => '√',
	},
	0xef => {
		0x00 => 'setDate(',
		0x01 => 'setTime(',
		0x02 => 'checkTmr(',
		0x03 => 'setDtFmt(',
		0x04 => 'setTmFmt(',
		0x05 => 'timeCnv(',
		0x06 => 'dayOfWk(',
		0x07 => 'getDtStr(',
		0x08 => 'getTmStr(',
		0x09 => 'getDate',
		0x0a => 'getTime',
		0x0b => 'startTmr',
		0x0c => 'getDtFmt',
		0x0e => 'getTmFmt',
		0x0f => 'isClockOn',
		0x10 => 'ClockOn',
		0x11 => 'ClockOff',
		0x12 => 'OpenLib(',
		0x13 => 'ExecLib',
		0x14 => 'invT(',
		0x15 => 'χ²GOF-Test(',
		0x16 => 'LinRegTInt',
		0x17 => 'Manual-Fit',
	},
};
local $/;

sub print_header {
	my $text = join(' ', @_);
	print "// $text\n";
}

sub header_type($) {
	my $header = shift;
	given (ord(substr($header, 0x3b, 1))) {
		when(0x00) { return('var') }
		when(0x01) { return('list') }
		when(0x02) { return('matrix') }
		when(0x03) { return('equation') }
		when(0x04) { return('string') }
		when(0x05) { return('program') }
		when(0x10) { return('zoom') }
		when(0x0f) { return('window') }
		default { return(sprintf('0x%02x', $_)) }
	}
}

sub header_name($) {
	my $header = shift;
	my $name;
	given (header_type($header)) {
		when('var') { $name = substr($header, 0x3c, 1) }
		when('matrix') { $name = substr($header, 0x3d, 1) }
		when('string') { $name = (ord(substr($header, 0x3d, 1)) + 1) % 10 }
		when('program') {
			$name = substr($header, 0x3c, 10);
			$name =~ s/\x00/ /g;
		}
		when('list') {
			$name = ord(substr($header, 0x3e, 1));
			$name &= 0x0f;
		}
	}
	return($name);
}

sub header_size($) {
	my $header = shift;
	my $size;
	$size->{full} = ord(substr($header, 0x46, 1)) + 255 * ord(substr($header, 0x47, 1));
	given(header_type($header)) {
		when('list') {
			$size->{items} = ord(substr($header, 0x48, 1));
		}
		when('matrix') {
			$size->{cols} = ord(substr($header, 0x48, 1));
			$size->{rows} = ord(substr($header, 0x49, 1));
		}
		when(['program', 'string', 'equation']) {
			$size->{source} = ord(substr($header, 0x48, 1)) + 255 * ord(substr($header, 0x49, 1));
		}
	}
	return($size);
}

sub header_compat($) {
	return(substr(shift, 0x02, 4));
}

sub header_datestr($) {
	return(substr(shift, 0x1d, 19));
}

getopts('ih', \%opts);

$file = shift;
open(my $input, '<', $file) or die("Cannot open $file: $!");
binmode($input);
read($input, $header, $headerlength);
$program = <$input>;
close($input);

# The last two bytes don't contain program code
$footer = substr($program, -$footerlength, $footerlength, '');
$length = length($program);
$offset = 0;

# Parse the header
%header = (
	compat  => header_compat($header),
	datestr => header_datestr($header),
	type    => header_type($header),
	name    => header_name($header),
	size    => header_size($header),
);


if ($opts{h}) {
	print_header('Compatibility:', $header{compat});
	print_header('Extracted at :', $header{datestr});
	print_header('Type         :', $header{type});
	print_header('Name         :', $header{name});
	print_header('Length w/o header:', $header{size}->{full});
	if ($header{type} eq 'matrix') {
		print_header('Matrix dimensions:', join('x', @{$header{size}}{'rows', 'cols'}));
	} elsif ($header{type} eq 'list') {
		print_header('List length  :', $header{size}->{items});
	} elsif ($header{type} eq 'string') {
		print_header('String length:', $header{size}->{source});
	} elsif ($header{type} eq 'program') {
		print_header('Program size :', $header{size}->{source});
	} elsif ($header{type} eq 'equation') {
		print_header('Payload length:', $header{size}->{source});
	}
}


# And now, the actual file content
if ($header{type} ~~ ['program', 'equation']) {
	while($offset < $length) {
		$char = ord(substr($program, $offset++, 1));
		if (exists($all{$char})) {
			$out = $all{$char};
		} elsif (exists($special->{$char})) {
			$char2 = ord(substr($program, $offset++, 1));
			$out = $special->{$char}->{$char2};
		} else {
			printf STDERR (
				"Unknown byte 0x%02x at %04x\n",
				$char,
				$headerlength + $offset - 1,
			);
			$out = chr($char);
		}
		if ($opts{i}) {
			if ($out =~ /Then|While|Repeat|For/) {
				$indent++;
			} elsif ($out =~ /Else/) {
				$rindent--;
			} elsif ($out =~ /End/) {
				$indent--;
				$rindent--;
			}
		}
		$cache .= $out;
		if ($out eq "\n") {
			print "\t" x $rindent;
			$rindent = $indent;
			print $cache;
			$cache = '';
		}
	}
	print "$cache\n";
} elsif ($header{type} ~~ ['matrix', 'list', 'var', 'zoom', 'window']) {
	my ($exp, $digit);
	my $i = 0;
	my @values;

	if ($header{type} eq 'var') {
		# Variables have a shorter header
		substr($program, 0, 0, substr($header, -2, 2));
		$length = length($program);
	}

	while ($offset+9 <= $length) {
		$i++;
		$digit = '';
		if (ord(substr($program, $offset++, 1)) >= 0x80) {
			$digit .= '-';
		}
		$exp = ord(substr($program, $offset++, 1)) - 0x80;
		for(1 .. 7) {
			$char = ord(substr($program, $offset++, 1));
			$digit .= $char >> 4;
			$digit .= $char & 0x0f;
		}
		substr($digit, 1 + ($digit <= 0), 0, '.');
		$digit *= 10 ** $exp;
		unless ($header{type} eq 'zoom') {
			printf('%-8s', $digit);
		} else {
			push(@values, $digit);
		}
		if ($header{type} eq 'matrix' and $i == $header{size}->{cols} or $header{type} eq 'var') {
			print "\n";
			$i = 0;
		} elsif ($header{type} eq 'matrix') {
			print ' | ';
		} elsif ($header{type} ne 'zoom') {
			print ' ';
		}
	}
	if ($header{type} eq 'zoom') {
		print "Xmin = $values[0]\n";
		print "Xmax = $values[1]\n";
		print "Xscl = $values[2]\n";
		print "Ymin = $values[3]\n";
		print "Ymax = $values[4]\n";
		print "Yscl = $values[5]\n";
	}
} elsif ($header{type} eq 'string') {
	while($offset < $length) {
		print substr($program, $offset++, 1);
	}
	print "\n";
} else {
	print STDERR "file type $header{type} not supported\n";
	exit 1;
}

__END__

=head1 NAME

tibtoa - Texas Instruments TI8x Binary to ASCII converter

=head1 SYNOPSIS

B<tibtoa> [ B<-hi> ] I<file>

=head1 DESCRIPTION

B<tibtoa> converts the binary files dumped from a calculator
(for example by tilp(1)) into human-readable text. The name is not quite right,
though - for programs, it also uses various unicode chars, not plain ASCII.

B<tibtoa> reads in the file specified on the commandline and prints the result
to STDOUT. Errors, such as unknown  bytes in the source, go to STDERR.

Currently, the following file types are supported:
B<.8Xv> (variable), B<.8Xl> (list), B<.8Xm> (matrix), B<.8Xe> (equation),
B<.8Xs> (string), B<.8Xp> (program).

=head1 OPTIONS

=over

=item B<-i>

Indent the content of for, while, if, etc. statements

=item B<-h>

Print the content of the file header before the file content, prefixed by '//'

=back