/**
 ** Ipack.cc - Create/extract image Flex files using the .png format.
 **
 ** Written: 2/19/2002 - JSF, with lots of code borrowed from Tristan's
 *      Gimp Plugin.
 **/

/*
 *  Copyright (C) 2002-2022  The Exult Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#ifdef HAVE_CONFIG_H
#	include <config.h>
#endif

#include "Flex.h"
#include "exceptions.h"
#include "ibuf8.h"
#include "pngio.h"
#include "vgafile.h"

#include <unistd.h>

#include <cstdio>
#include <cstdlib>
#include <fstream>
#include <iomanip>
#include <iostream>
#include <memory>
#include <vector>

using std::cerr;
using std::cout;
using std::endl;
using std::exit;
using std::ifstream;
using std::istream;
using std::ofstream;
using std::ostream;
using std::setw;
using std::size_t;
using std::strcat;
using std::strcpy;
using std::strlen;
using std::strncmp;
using std::unique_ptr;
using std::vector;

/*
 *  A shape specification:
 */
struct Shape_spec {
	char* filename   = nullptr;    // Should be allocated.
	int   nframes    = 0;          // # frames in shape.
	bool  flat       = false;      // A 'flat' shape.
	bool  bycol      = false;      // If dim0_tiles > 0, go down first.
	int   dim0_tiles = 0;          // File consists of 8x8 (flat) tiles.

	Shape_spec() = default;

	Shape_spec(const Shape_spec& other)
			: nframes(other.nframes), flat(other.flat), bycol(other.bycol),
			  dim0_tiles(other.dim0_tiles) {
		if (other.filename) {
			filename = newstrdup(other.filename);
		} else {
			filename = nullptr;
		}
	}

	~Shape_spec() {
		delete[] filename;
	}
};

using Shape_specs = vector<Shape_spec>;

/*
 *  Add all shapes to 'specs'.
 */

static void Get_all_shapes(
		char*        imagename,    // Archive name returned.
		char*        basename,
		Shape_specs& specs    // Shape specs. returned here.
) {
	const size_t namelen = strlen(basename) + strlen("SSSS_") + 1;
	Vga_file     ifile;
	try {
		ifile.load(imagename);    // May throw an exception.
	} catch (exult_exception& e) {
		cerr << e.what() << endl;
		exit(1);
	}
	const int nshapes = ifile.get_num_shapes();
	specs.resize(nshapes);
	for (int i = 0; i < nshapes; ++i) {
		const int nframes = ifile.get_num_frames(i);
		if (!nframes) {
			continue;
		}
		char* shapename = new char[namelen];
		snprintf(shapename, namelen, "%s%04d_", basename, i);
		specs[i].flat     = false;
		specs[i].nframes  = nframes;
		specs[i].filename = shapename;
	}
}

/*
 *  Skip white space.
 */

static char* Skip_space(char* ptr) {
	while (isspace(static_cast<unsigned char>(*ptr))) {
		ptr++;
	}
	return ptr;
}

/*
 *  Find white space (or null).
 */

static char* Find_space(char* ptr) {
	while (*ptr && !isspace(static_cast<unsigned char>(*ptr))) {
		ptr++;
	}
	return ptr;
}

/*
 *  Pass a filename spec. which can have a "(nnn xxx)" at its end.
 */

static char* Pass_file_spec(char* ptr) {
	int paren_depth = 0;
	while (*ptr
		   && (paren_depth > 0 || !isspace(static_cast<unsigned char>(*ptr)))) {
		if (*ptr == '(') {
			paren_depth++;
		} else if (*ptr == ')') {
			paren_depth--;
		}
		ptr++;
	}
	return ptr;
}

/*
 *  Parse a number, and quit with an error msg. if not found.
 */

static long Get_number(
		int         linenum,    // For printing errors.
		const char* errmsg, char* ptr,
		char*& endptr    // ->past number and spaces returned.
) {
	const long num = strtol(ptr, &endptr, 0);
	if (endptr == ptr) {    // No #?
		cerr << "Line " << linenum << ":  " << errmsg << endl;
		exit(1);
	}
	endptr = Skip_space(endptr);
	return num;
}

/*
 *  Return the next token, or quit with an error.
 *
 *  Output: ->copy of token.
 */

static char* Get_token(
		int    linenum,    // For printing errors.
		char*  ptr,        // Where to start looking.
		char*& endptr      // ->past token returned.
) {
	ptr    = Skip_space(ptr + 7);
	endptr = Find_space(ptr);
	if (endptr == ptr) {
		cerr << "Line #" << linenum << ":  Expecting a name" << endl;
		exit(1);
	}
	const char sav = *endptr;
	*endptr        = 0;
	char* token    = newstrdup(ptr);
	*endptr        = sav;
	return token;
}

/*
 *  Read in script, with the following format:
 *      Max. text length is 1024.
 *      A line beginning with a '#' is a comment.
 *      'archive imgfile' specifies name of the image archive.
 *      'palette palfile' specifies the palette file (which, if a
 *          Flex, contains palette in entry 0).
 *      'nnn/fff:filename' indicates shape #nnn will consist of fff
 *          frames in files "filenameii.png", where ii is the
 *          frame #.
 *      'nnn/fff:filename(cc across)' indicates filename is a .png
 *          consisting of 8x8 flat tiles, to be taken rowwise with
 *          each row having cc columns.
 *      'nnn/fff:filename(rr down)' indicates filename is a .png
 *          consisting of 8x8 flat tiles, to be taken columnwise
 *          with each column having rr rows.
 *      Filename may be followed by 'flat' to indicate 8x8 non-RLE
 *          shape.
 *      'all:filename' indicates that all shapes/frames should be
 *          extracted into "filenamessss_ii.png", where ssss
 *          is the shape# and ii is the frame#.
 */

static void Read_script(
		istream&     in,
		char*&       imagename,    // Archive name returned.
		char*&       palname,      // Palette name returned.
		Shape_specs& specs         // Shape specs. returned here.
) {
	imagename = nullptr;
	specs.resize(0);    // Initialize.
	specs.reserve(1200);
	char buf[1024];
	int  linenum = 0;
	while (!in.eof()) {
		++linenum;
		in.get(buf, sizeof(buf));
		char delim;    // Check for end-of-line.
		in.get(delim);
		if (delim != '\n' && !in.eof()) {
			cerr << "Line #" << linenum << " is too long" << endl;
			exit(1);
		}
		if (!buf[0]) {
			continue;    // Empty line.
		}
		char* ptr = Skip_space(&buf[0]);
		if (*ptr == '#') {
			continue;    // Comment.
		}
		char* endptr;
		if (strncmp(ptr, "archive", 7) == 0) {
			// Archive name.
			imagename = Get_token(linenum, ptr, endptr);
			continue;
		}
		if (strncmp(ptr, "palette", 7) == 0) {
			palname = Get_token(linenum, ptr, endptr);
			continue;
		}
		if (strncmp(ptr, "all:", 4) == 0) {
			if (!imagename) {
				cerr << "Line #" << linenum
					 << ":  Archive name not given before 'all'" << endl;
				exit(1);
			}
			ptr    = Skip_space(ptr + 4);
			endptr = Find_space(ptr);
			if (endptr == ptr) {
				cerr << "Line #" << linenum << ":  Missing filename" << endl;
				exit(1);
			}
			*endptr = 0;
			Get_all_shapes(imagename, ptr, specs);
			return;
		}
		// Get shape# in decimal, hex, or oct.
		const size_t shnum
				= Get_number(linenum, "Shape # missing", ptr, endptr);
		if (*endptr != '/') {
			cerr << "Line #" << linenum << ":  Missing '/' after shape number"
				 << endl;
			exit(1);
		}
		ptr = endptr + 1;
		const long nframes
				= Get_number(linenum, "Frame count missing", ptr, endptr);
		if (*endptr != ':') {
			cerr << "Line #" << linenum << ":  Missing ':' after frame count"
				 << endl;
			exit(1);
		}
		ptr    = Skip_space(endptr + 1);
		endptr = Pass_file_spec(ptr);
		if (endptr == ptr) {
			cerr << "Line #" << linenum << ":  Missing filename" << endl;
			exit(1);
		}
		// Get ->past filename.
		char* past_end = *endptr ? Skip_space(endptr + 1) : endptr;
		*endptr        = 0;
		if (shnum >= specs.size()) {
			specs.resize(shnum + 1);
		}
		specs[shnum].flat    = (strncmp(past_end, "flat", 4) == 0);
		specs[shnum].nframes = nframes;
		char fname[300];
		char dir[300];
		int  dim0_cnt;    // See if it's a tiles spec.
		if (sscanf(ptr, "%[^(](%d %s)", &fname[0], &dim0_cnt, &dir[0]) == 3) {
			if (!specs[shnum].flat) {
				cerr << "Line #" << linenum
					 << ":  Tiled file not specified 'flat'" << endl;
				exit(1);
			}
			specs[shnum].dim0_tiles = dim0_cnt;
			specs[shnum].bycol      = strncmp(dir, "down", 4) == 0;
			specs[shnum].filename   = newstrdup(fname);
		} else {
			specs[shnum].filename = newstrdup(ptr);
		}
	}
}

/*
 *  Modify a palette by fixed amounts and/or percentages.
 */

static void Modify_palette(
		const unsigned char* from,    // Rgb values to start with,
		//   each range 0-255.
		unsigned char* to,               // Result stored here.
		int            palsize,          // 0-256.
		int roff, int goff, int boff,    // Add these offsets first.
		int r256, int g256, int b256     // Modify by x/256.
) {
	for (int i = 0; i < 3 * palsize;) {
		int r = from[i] + roff;    // First the offsets.
		// Then percentage.
		r += (r * r256) / 256;
		if (r < 0) {
			r = 0;
		}
		if (r > 255) {
			r = 255;
		}
		to[i++] = r;
		int g   = from[i] + goff;
		g += (g * g256) / 256;
		if (g < 0) {
			g = 0;
		}
		if (g > 255) {
			g = 255;
		}
		to[i++] = g;
		int b   = from[i] + boff;
		b += (b * b256) / 256;
		if (b < 0) {
			b = 0;
		}
		if (b > 255) {
			b = 255;
		}
		to[i++] = b;
	}
}

/*
 *  Modify a palette by removing all color.
 */

static void Greyify_palette(
		const unsigned char* from,    // Rgb values to start with,
		//   each range 0-255.
		unsigned char* to,        // Result stored here.
		int            palsize    // 0-256.
) {
	for (int i = 0; i < palsize; i++) {
		const int ind = i * 3;
		// Take average.
		const int ave = (from[ind] + from[ind + 1] + from[ind + 2]) / 3;
		to[ind] = to[ind + 1] = to[ind + 2] = ave;
	}
}

/*
 *  Convert a palette to values 0-63.
 */

static void Convert_palette63(
		const unsigned char* from,    // 3*palsize, values 0-255.
		unsigned char*       to,      // 3*256.  Values 0-63 returned, with
		//   colors > palsize 0-filled.
		int palsize    // # entries.
) {
	int i;    // Convert 0-255 to 0-63 for Exult.
	for (i = 0; i < 3 * palsize; i++) {
		to[i] = from[i] / 4;
	}
	memset(to + i, 0, 3 * 256 - i);    // 0-fill the rest.
}

/*
 *  Write out a palette as text.
 */

static void Write_text_palette(
		char*                palname,    // Base name.  '.txt' is appended.
		const unsigned char* palette,    // RGB's, 0-255.
		int                  palsize     // # colors in palette
) {
	// Write out as (Gimp) text.
	char* txtpal = new char[strlen(palname) + 10];
	strcpy(txtpal, palname);
	strcat(txtpal, ".txt");
	cout << "Creating text (Gimp) palette '" << txtpal << "'" << endl;
	ofstream pout(txtpal);             // OKAY that it's a 'text' file.
	pout << "GIMP palette" << endl;    // MUST be this for Gimp to use.
	pout << "Palette from Exult's Ipack" << endl;
	int i;    // Skip 0's at end.
	for (i = palsize - 1; i > 0; i--) {
		if (palette[3 * i] != 0 || palette[3 * i + 1] != 0
			|| palette[3 * i + 2] != 0) {
			break;
		}
	}
	const int last_color = i;
	for (i = 0; i <= last_color; i++) {
		const int r = palette[3 * i];
		const int g = palette[3 * i + 1];
		const int b = palette[3 * i + 2];
		pout << setw(3) << r << ' ' << setw(3) << g << ' ' << setw(3) << b
			 << endl;
	}
	pout.close();
	delete[] txtpal;
}

const unsigned char transp = 255;    // Transparent pixel.

/*
 *  Write out one frame as a .png.
 */

static void Write_frame(
		char*          basename,    // Base filename to write.
		int            frnum,       // Frame #.
		Shape_frame*   frame,       // What to write.
		unsigned char* palette      // 3*256 bytes.
) {
	assert(frame != nullptr);
	const size_t namelen  = strlen(basename) + 30;
	char*        fullname = new char[namelen];
	snprintf(fullname, namelen, "%s%02d.png", basename, frnum);
	cout << "Writing " << fullname << endl;
	const int     w = frame->get_width();
	const int     h = frame->get_height();
	Image_buffer8 img(w, h);    // Render into a buffer.
	img.fill8(transp);          // Fill with transparent pixel.
	frame->paint(&img, frame->get_xleft(), frame->get_yabove());
	int xoff = 0;
	int yoff = 0;
	if (frame->is_rle()) {
		xoff = -frame->get_xright();
		yoff = -frame->get_ybelow();
	}
	// Write out to the .png.
	if (!Export_png8(
				fullname, transp, w, h, w, xoff, yoff, img.get_bits(), palette,
				256, true)) {
		throw file_write_exception(fullname);
	}
	delete[] fullname;
}

/*
 *  Write out palettes.  The first is the one given, and the rest are
 *  automatically generated to work with the Exult engine (see
 *  palettes.h for definitions).
 */

void Write_palettes(
		char*          palname,
		unsigned char* palette,    // 3 bytes for each color.
		int            palsize     // # entries.
) {
	cout << "Creating new palette file '" << palname
		 << "' using first file's palette" << endl;
	unsigned char palbuf[3 * 256];    // We always write 256 colors.
	if (palsize > 256) {              // Shouldn't happen.
		palsize = 256;
	}
	OFileDataSource out(palname);    // May throw exception.
	Flex_writer     writer(out, "Exult palette by Ipack", 11);
	// Entry 0 (DAY):
	const char* palptr = reinterpret_cast<const char*>(palbuf);
	Convert_palette63(palette, &palbuf[0], palsize);
	writer.write_object(palptr, sizeof(palbuf));
	// Entry 1 (DUSK):
	Modify_palette(palette, palbuf, palsize, 0, 0, 0, -64, -64, -64);
	Convert_palette63(palbuf, palbuf, palsize);
	writer.write_object(palptr, sizeof(palbuf));
	// Entry 2 (NIGHT):
	Modify_palette(palette, palbuf, palsize, 0, 0, 0, -128, -128, -128);
	Convert_palette63(palbuf, palbuf, palsize);
	writer.write_object(palptr, sizeof(palbuf));
	// Entry 3 (INVISIBLE):
	Greyify_palette(palette, palbuf, palsize);
	Convert_palette63(palbuf, palbuf, palsize);
	writer.write_object(palptr, sizeof(palbuf));
	// Entry 4 (unknown):
	Convert_palette63(palette, palbuf, palsize);
	writer.write_object(palptr, sizeof(palbuf));
	// Entry 5 (HAZE):
	Modify_palette(palette, palbuf, palsize, 184, 184, 184, -32, -32, -32);
	Convert_palette63(palbuf, palbuf, palsize);
	writer.write_object(palptr, sizeof(palbuf));
	// Entry 6 (a bit brighter than 2):
	Modify_palette(palette, palbuf, palsize, 0, 0, 0, -96, -96, -96);
	Convert_palette63(palbuf, palbuf, palsize);
	writer.write_object(palptr, sizeof(palbuf));
	// Entry 7 (a bit warmer):
	Modify_palette(palette, palbuf, palsize, 30, 0, 0, -96, -96, -96);
	Convert_palette63(palbuf, palbuf, palsize);
	writer.write_object(palptr, sizeof(palbuf));
	// Entry 8 (hit in combat):
	Modify_palette(palette, palbuf, palsize, 64, 0, 0, 384, -20, -20);
	Convert_palette63(palbuf, palbuf, palsize);
	writer.write_object(palptr, sizeof(palbuf));
	// Entry 9 (unknown):
	Convert_palette63(palette, palbuf, palsize);
	writer.write_object(palptr, sizeof(palbuf));
	// Entry 10 (LIGHTNING):
	Modify_palette(palette, palbuf, palsize, 32, 32, 0, 256, 256, -20);
	Convert_palette63(palbuf, palbuf, palsize);
	writer.write_object(palptr, sizeof(palbuf));
	// Write out in Gimp format.
	Write_text_palette(palname, palette, palsize);
}

/*
 *  Write tiles from a single input file to and Exult image file.
 */

static void Write_exult_from_tiles(
		Flex_writer& writer,      // What to write to.
		char*        filename,    // Filename to read.
		int          nframes,     // # frames.
		bool         bycol,       // If true, go down each column first,
		//   else go across each row first.
		int   dim0_cnt,    // If bycol, #rows; else #cols.
		char* palname      // Store palette here if !0.
) {
	cout << "Reading " << filename << " tiled"
		 << (bycol ? ", by cols" : ", by rows") << " first" << endl;
	// Figure #tiles in other dim.
	const int dim1_cnt = (nframes + dim0_cnt - 1) / dim0_cnt;
	int       needw;
	int       needh;    // Figure min. image dims.
	if (bycol) {
		needh = dim0_cnt * 8;
		needw = dim1_cnt * 8;
	} else {
		needw = dim0_cnt * 8;
		needh = dim1_cnt * 8;
	}
	// Save starting position.
	int            w;
	int            h;
	int            rowsize;
	int            xoff;
	int            yoff;
	int            palsize;
	unsigned char* pixels;
	unsigned char* palette;
	// Import, with 255 = transp. index.
	if (!Import_png8(
				filename, 255, w, h, rowsize, xoff, yoff, pixels, palette,
				palsize)) {
		throw file_read_exception(filename);
	}
	if (w < needw || h < needh) {
		cerr << "File " << filename << " image is too small.  " << needw << 'x'
			 << needh << " required" << endl;
		exit(1);
	}
	writer.write_object([&](ODataSource& out) {
		for (int frnum = 0; frnum < nframes; frnum++) {
			int x;
			int y;
			if (bycol) {
				y = frnum % dim0_cnt;
				x = frnum / dim0_cnt;
			} else {
				x = frnum % dim0_cnt;
				y = frnum / dim0_cnt;
			}
			unsigned char* src = pixels + w * 8 * y + 8 * x;
			for (int row = 0; row < 8; row++) {
				// Write it out.
				out.write(src, 8);
				src += w;
			}
		}
	});
	delete[] pixels;
	if (palname) {
		Write_palettes(palname, palette, palsize);
	}
	delete[] palette;
}

/*
 *  Write a shape's frames to an Exult image file.
 */

static void Write_exult(
		Flex_writer& out,         // What to write to.
		char*        basename,    // Base filename for files to read.
		int          nframes,     // # frames.
		bool         flat,        // Store as 8x8 flats.
		char*        palname      // Store palette with here if !0.
) {
	Shape        shape(nframes);
	const size_t namelen  = strlen(basename) + 30;
	char*        fullname = new char[namelen];
	int          frnum;    // Read in frames.
	for (frnum = 0; frnum < nframes; frnum++) {
		snprintf(fullname, namelen, "%s%02d.png", basename, frnum);
		cout << "Reading " << fullname << endl;
		int            w;
		int            h;
		int            rowsize;
		int            xoff;
		int            yoff;
		int            palsize;
		unsigned char* pixels;
		unsigned char* palette;
		// Import, with 255 = transp. index.
		if (!Import_png8(
					fullname, 255, w, h, rowsize, xoff, yoff, pixels, palette,
					palsize)) {
			throw file_read_exception(fullname);
		}
		int xleft;
		int yabove;
		if (flat) {
			xleft = yabove = 8;
			if (w != 8 || h != 8 || rowsize != 8) {
				cerr << "Image in '" << fullname << "' is not flat" << endl;
				exit(1);
			}
		} else {    // RLE. xoff,yoff are neg. from bottom.
			xleft  = w + xoff - 1;
			yabove = h + yoff - 1;
		}
		shape.set_frame(
				std::make_unique<Shape_frame>(
						pixels, w, h, xleft, yabove, !flat),
				frnum);
		delete[] pixels;
		if (palname) {    // Write palette for first frame.
			Write_palettes(palname, palette, palsize);
			palname = nullptr;
		}
		delete[] palette;
	}
	out.write_object(shape);
	delete[] fullname;
}

/*
 *  Create an archive from a set of image files.  May throw an exception.
 */

static void Create(
		char*        imagename,    // Image archive name.
		char*        palname,      // Palettes file (palettes.flx).
		Shape_specs& specs,        // List of things to extract.
		const char*  title         // For storing in Flex file.
) {
	if (palname && U7exists(palname)) {    // Palette?
		cout << "Palette file '" << palname
			 << "' exists, so we won't overwrite it" << endl;
		palname = nullptr;
	}
	OFileDataSource out(imagename);    // May throw exception.
	Flex_writer     writer(out, title, specs.size());
	for (auto& spec : specs) {
		char* basename = spec.filename;
		if (basename) {    // Not empty?
			const int dim0_cnt = spec.dim0_tiles;
			if (dim0_cnt > 0) {
				Write_exult_from_tiles(
						writer, basename, spec.nframes, spec.bycol,
						spec.dim0_tiles, palname);
			} else {
				Write_exult(writer, basename, spec.nframes, spec.flat, palname);
			}
			palname = nullptr;    // Only write 1st palette.
		} else {
			writer.empty_object();
		}
	}
}

/*
 *  Update an archive with a set of image files.  May throw an exception.
 *  The archive is rewritten with its original shapes, plus those
 *  specified in the script.
 */

static void Update(
		char*        imagename,    // Image archive name.
		char*        palname,      // Palettes file (palettes.flx).
		Shape_specs& specs,        // List of things to extract.
		const char*  title         // For storing in Flex file.
) {
	if (palname && U7exists(palname)) {    // Palette?
		cout << "Palette file '" << palname
			 << "' exists, so we won't overwrite it" << endl;
		palname = nullptr;
	}
	FlexFile     in(imagename);    // May throw exception.
	const size_t oldcnt = in.number_of_objects();
	vector<unique_ptr<unsigned char[]>> data(
			oldcnt);    // Read in all the entries.
	vector<int> lengths(oldcnt);
	size_t      i;
	for (i = 0; i < oldcnt; i++) {
		size_t len;
		data[i]    = in.retrieve(i, len);
		lengths[i] = len;
		if (!len) {    // Empty?
			data[i].reset();
		}
	}
	OFileDataSource out(imagename);    // May throw exception.
	const size_t    newcnt = oldcnt > specs.size() ? oldcnt : specs.size();
	Flex_writer     writer(out, title, newcnt);
	for (i = 0; i < newcnt; i++) {    // Write out new entries.
		// New entry for this shape?
		if (i < specs.size() && specs[i].filename != nullptr) {
			Write_exult(
					writer, specs[i].filename, specs[i].nframes, specs[i].flat,
					palname);
			palname = nullptr;    // Only write 1st palette.
		}
		// Write old entry.
		else if (i < oldcnt && data[i]) {
			writer.write_object(data[i].get(), lengths[i]);
		} else {
			writer.empty_object();
		}
	}
}

/*
 *  Extract from the archive.  May throw an exception.
 */

static void Extract(
		char*        imagename,    // Image archive name.
		char*        palname,      // Palettes file (palettes.flx).
		Shape_specs& specs         // List of things to extract.
) {
	if (!palname) {
		cerr << "No palette name (i.e., 'palettes.flx') given" << endl;
		exit(1);
	}
	const U7object pal(palname, 0);    // Get palette 0.
	size_t         len;
	// This may throw an exception
	auto palbuf = pal.retrieve(len);
	for (size_t i = 0; i < len; i++) {    // Turn into full bytes.
		palbuf[i] *= 4;                   // Exult palette vals are 0-63.
	}
	Vga_file ifile(imagename);    // May throw an exception.
	for (auto it = specs.begin(); it != specs.end(); ++it) {
		char* basename = it->filename;
		if (!basename) {    // Empty?
			continue;
		}
		const int shnum = it - specs.begin();
		if (shnum >= ifile.get_num_shapes()) {
			cerr << "Shape #" << shnum << " > #shapes in file" << endl;
			continue;
		}
		// Read in all frames.
		Shape*    shape   = ifile.extract_shape(shnum);
		const int nframes = shape->get_num_frames();
		if (nframes != it->nframes) {
			cerr << "Warning: # frames (" << it->nframes << ") given for shape "
				 << shnum << " doesn't match actual count (" << nframes << ")"
				 << endl;
		}
		for (int f = 0; f < nframes; f++) {
			Write_frame(basename, f, shape->get_frame(f), palbuf.get());
		}
	}
}

/*
 *  Print usage and exit.
 */

static void Usage() {
	cerr << "Usage: ipack -[x|c|u] script" << endl;
	exit(1);
}

/*
 *  Create or extract from Flex files consisting of shapes.
 */

int main(int argc, char** argv) {
	if (argc < 3 || argv[1][0] != '-') {
		Usage();    // (Exits.)
	}
	char*                         scriptname = argv[2];
	char*                         imagename  = nullptr;
	char*                         palname    = nullptr;
	Shape_specs                   specs;    // Shape specs. stored here.
	std::unique_ptr<std::istream> pSpecin;
	try {
		pSpecin = U7open_in(scriptname, true);
	} catch (exult_exception& e) {
		cerr << e.what() << endl;
		exit(1);
	}
	if (!pSpecin) {
		cerr << "Failed to open " << scriptname << endl;
		exit(1);
	}
	auto& specin = *pSpecin;
	Read_script(specin, imagename, palname, specs);
	if (!imagename) {
		cerr << "No archive name (i.e., 'shapes.vga') given" << endl;
		exit(1);
	}
	switch (argv[1][1]) {    // Which function?
	case 'c':                // Create.
		try {
			Create(imagename, palname, specs, "Exult image file");
		} catch (exult_exception& e) {
			cerr << e.what() << endl;
			exit(1);
		}
		break;
	case 'x':    // Extract .png files.
		try {
			Extract(imagename, palname, specs);
		} catch (exult_exception& e) {
			cerr << e.what() << endl;
			exit(1);
		}
		break;
	case 'u':
		try {
			Update(imagename, palname, specs, "Exult image file");
		} catch (exult_exception& e) {
			cerr << e.what() << endl;
			exit(1);
		}
		break;
	default:
		Usage();
	}
	return 0;
}