/*
 *  Warehouse for JoeyLib - A Sokoban Clone
 *  Copyright (C) 2020 Scott Duensing <scott@kangaroopunch.com>
 *
 *  This software is provided 'as-is', without any express or implied
 *  warranty.  In no event will the authors be held liable for any damages
 *  arising from the use of this software.
 *
 *  Permission is granted to anyone to use this software for any purpose,
 *  including commercial applications, and to alter it and redistribute it
 *  freely, subject to the following restrictions:
 *
 *  1. The origin of this software must not be misrepresented; you must not
 *     claim that you wrote the original software. If you use this software
 *     in a product, an acknowledgment in the product documentation would be
 *     appreciated but is not required.
 *  2. Altered source versions must be plainly marked as such, and must not be
 *     misrepresented as being the original software.
 *  3. This notice may not be removed or altered from any source distribution.
*/


#include <stdio.h>
#include <string.h>
#include <stdint.h>


#define MAX_WIDTH  20
#define MAX_HEIGHT 12
#define MAX_LINE   8192


static char puzzleChars[] = { "_# .$@+*" };


int isLegal(char c) {
	int  x;

	if (c == '-') c = ' ';

	for (x=0; x<(int)strlen(puzzleChars); x++) {
		if (puzzleChars[x] == c) {
			return x + 1;
		}
	}
	return 0;
}


int main(int argc, char *argv[]) {

	char           puzzle[MAX_WIDTH][MAX_WIDTH];
	char           line[MAX_LINE];  // Ooo!  Look!  Potential buffer overflow!
	char           height;
	unsigned char  width;
	unsigned char  b1;
	unsigned char  b2;
	int16_t        x;
	int16_t        y;
	int16_t        count;
	int32_t        bytes;
	FILE          *in;
	FILE          *puzzles;
	FILE          *index;

	if (argc != 4) {
		printf("%s:  [letslogic.txt] [puzzles.dat] [index.dat]\n", argv[0]);
		return 1;
	}

	in = fopen(argv[1], "rt");
	if (!in) {
		printf("Unable to read %s\n", argv[1]);
		return 2;
	}

	puzzles = fopen(argv[2], "wb");
	if (!puzzles) {
		fclose(in);
		printf("Unable to write %s\n", argv[2]);
		return 2;
	}

	index = fopen(argv[3], "wb");
	if (!index) {
		fclose(puzzles);
		fclose(in);
		printf("Unable to write %s\n", argv[3]);
		return 2;
	}

	// Skip two bytes at the front of the index file to later write the puzzle count into.
	fputc(0, index);
	fputc(0, index);

	bytes  =  0;
	count  =  0;
	height = -1;
	width  =  0;

	while (fgets(line, MAX_LINE, in)) {
		// Is there a newline to remove?
		if ((strlen(line) > 0) && (line[strlen(line) - 1] == '\n')) {
			line[strlen(line) - 1] = 0;
		}
		// Is there anything on this line?
		if (strlen(line) > 0) {
			// Is this a puzzle line?
			if (isLegal(line[0]) > 0) {
				// Got it.  Read this line.
				if (width < strlen(line)) {
					width = strlen(line);
					//printf("Width %d\n", width);
				}
				height++;
				for (x=0; x<width; x++) {
					puzzle[x][(int)height] = line[x];
				}
			} else {
				// Not a puzzle line.  Were we currently reading a puzzle?
				if (height >= 0) {
					// Yep!  Output it!
					height++;  // Make it 1 based ('width' has been 1 based the whole time)
					if ((width & 1) == 1) {
						// Width must be even - fill new column with empty space
						for (y=0; y<height; y++) {
							puzzle[width][y] = '_';
						}
						width++;
						//printf("Increased width to %d\n", width);
					}
					// Save to index
					fwrite(&bytes, sizeof(int32_t), 1, index);
					// Save puzzle
					fputc(width, puzzles);
					fputc(height, puzzles);
					bytes += 2;
					// Write out the puzzle data, two tiles to a byte.
					//printf("%dx%d\n", width, height);
					for (y=0; y<height; y++) {
						for (x=0; x<width; x+=2) {
							b1 = isLegal(puzzle[x][y]) - 1;
							b2 = isLegal(puzzle[x + 1][y]) - 1;
							//printf("%c%c", puzzleChars[b1], puzzleChars[b2]);
							fputc((b1 << 4) + b2, puzzles);
							bytes++;
						}
						//printf("\n");
					}
					// Reset for next pass.
					count++;
					width  =  0;
					height = -1;
					printf("Puzzle %d imported, %d total bytes written.\n", count, bytes);
				}
			}
		}
	}

	// Seek back to the top and write the number of puzzles found.
	fflush(index);
	fseek(index, 0, SEEK_SET);
	fwrite(&count, sizeof(int16_t), 1, index);

	fclose(index);
	fclose(puzzles);
	fclose(in);

	return 0;
}