/*
 *  OpenSCAD (www.openscad.at)
 *  Copyright (C) 2009  Clifford Wolf <clifford@clifford.at>
 *
 *  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
 *
 */

#include "openscad.h"

#include <QFile>

DxfData::DxfData(double fn, double fs, double fa, QString filename, QString layername, double xorigin, double yorigin, double scale)
{
	handle_dep(filename);
	QFile f(filename);

	if (!f.open(QIODevice::ReadOnly | QIODevice::Text)) {
		PRINTF("WARNING: Can't open DXF file `%s'.", filename.toAscii().data());
		return;
	}

	QList<Line> lines;
	Grid2d< QVector<int> > grid;
	QHash< QString, QList<Line> > blockdata;

	bool in_entities_section = false;
	bool in_blocks_section = false;
	QString current_block;

#define ADD_LINE(_x1, _y1, _x2, _y2) do {                    \
     double _p1x = _x1, _p1y = _y1, _p2x = _x2, _p2y = _y2;  \
     if (!in_entities_section && !in_blocks_section)         \
       break;                                                \
     if (in_entities_section &&                              \
         !(layername.isNull() || layername == layer))        \
       break;                                                \
     grid.align(_p1x, _p1y);                                 \
     grid.align(_p2x, _p2y);                                 \
     grid.data(_p1x, _p1y).append(lines.count());            \
     grid.data(_p2x, _p2y).append(lines.count());            \
     if (in_entities_section)                                \
       lines.append(Line(p(_p1x, _p1y), p(_p2x, _p2y)));     \
     if (in_blocks_section && !current_block.isNull())       \
       blockdata[current_block].append(                      \
           Line(p(_p1x, _p1y), p(_p2x, _p2y)));              \
   } while (0)

	QString mode, layer, name, iddata;
	int dimtype = 0;
	double coords[7][2];
	double x1 = 0, x2 = 0, y1 = 0, y2 = 0;
	double radius = 0, start_angle = 0, stop_angle = 0;

	for (int i = 0; i < 7; i++)
	for (int j = 0; j < 2; j++)
		coords[i][j] = 0;

	QHash<QString, int> unsupported_entities_list;

	while (!f.atEnd())
	{
		QString id_str = QString(f.readLine()).remove("\n");
		QString data = QString(f.readLine()).remove("\n");

		bool status;
		int id = id_str.toInt(&status);

		if (!status)
			break;

		if (id >= 10 && id <= 16) {
			if (id == 11 || id == 12 || id == 16)
				coords[id-10][0] = data.toDouble() * scale;
			else
				coords[id-10][0] = (data.toDouble() - xorigin) * scale;
		}

		if (id >= 20 && id <= 26) {
			if (id == 21 || id == 22 || id == 26)
				coords[id-20][1] = data.toDouble() * scale;
			else
				coords[id-20][1] = (data.toDouble() - yorigin) * scale;
		}

		switch (id)
		{
		case 0:
			if (mode == "SECTION") {
				in_entities_section = iddata == "ENTITIES";
				in_blocks_section = iddata == "BLOCKS";
			}
			if (mode == "LINE") {
				ADD_LINE(x1, y1, x2, y2);
			}
			if (mode == "CIRCLE") {
				int n = get_fragments_from_r(radius, fn, fs, fa);
				for (int i = 0; i < n; i++) {
					double a1 = (2*M_PI*i)/n;
					double a2 = (2*M_PI*(i+1))/n;
					ADD_LINE(cos(a1)*radius + x1, sin(a1)*radius + y1,
							cos(a2)*radius + x1, sin(a2)*radius + y1);
				}
			}
			if (mode == "ARC") {
				int n = get_fragments_from_r(radius, fn, fs, fa);
				while (start_angle > stop_angle)
					stop_angle += 360.0;
				n = (int)ceil(n * (stop_angle-start_angle) / 360);
				for (int i = 0; i < n; i++) {
					double a1 = ((stop_angle-start_angle)*i)/n;
					double a2 = ((stop_angle-start_angle)*(i+1))/n;
					a1 = (start_angle + a1) * M_PI / 180.0;
					a2 = (start_angle + a2) * M_PI / 180.0;
					ADD_LINE(cos(a1)*radius + x1, sin(a1)*radius + y1,
							cos(a2)*radius + x1, sin(a2)*radius + y1);
				}
			}
			if (mode == "INSERT") {
				int n = blockdata[iddata].size();
				for (int i = 0; i < n; i++) {
					double a = -start_angle * M_PI / 180.0;
					double lx1 = blockdata[iddata][i].p[0]->x;
					double ly1 = blockdata[iddata][i].p[0]->y;
					double lx2 = blockdata[iddata][i].p[1]->x;
					double ly2 = blockdata[iddata][i].p[1]->y;
					double px1 = cos(a)*lx1 + sin(a)*ly1 + x1;
					double py1 = sin(a)*lx1 + cos(a)*ly1 + y1;
					double px2 = cos(a)*lx2 + sin(a)*ly2 + x1;
					double py2 = sin(a)*lx2 + cos(a)*ly2 + y1;
					ADD_LINE(px1, py1, px2, py2);
				}
			}
			if (mode == "DIMENSION" &&
					(layername.isNull() || layername == layer)) {
				dims.append(Dim());
				dims.last().type = dimtype;
				for (int i = 0; i < 7; i++)
				for (int j = 0; j < 2; j++)
					dims.last().coords[i][j] = coords[i][j];
				dims.last().angle = start_angle;
				dims.last().name = name;
			}
			if (mode == "BLOCK") {
				current_block = iddata;
			}
			if (mode == "ENDBLK") {
				current_block = QString();
			}
			if (in_blocks_section || (in_entities_section &&
					(layername.isNull() || layername == layer))) {
				if (mode != "SECTION" && mode != "ENDSEC" && mode != "DIMENSION" &&
						mode != "LINE" && mode != "ARC" && mode != "CIRCLE" &&
						mode != "BLOCK" && mode != "ENDBLK" && mode != "INSERT")
					unsupported_entities_list[mode]++;
			}
			mode = data;
			layer = QString();
			name = QString();
			iddata = QString();
			dimtype = 0;
			for (int i = 0; i < 7; i++)
			for (int j = 0; j < 2; j++)
				coords[i][j] = 0;
			x1 = x2 = y1 = y2 = 0;
			radius = start_angle = stop_angle = 0;
			break;
		case 1:
			name = data;
			break;
		case 2:
			iddata = data;
			break;
		case 8:
			layer = data;
			break;
		case 10:
			x1 = (data.toDouble() - xorigin) * scale;
			break;
		case 11:
			x2 = (data.toDouble() - xorigin) * scale;
			break;
		case 20:
			y1 = (data.toDouble() - yorigin) * scale;
			break;
		case 21:
			y2 = (data.toDouble() - yorigin) * scale;
			break;
		case 40:
			radius = data.toDouble() * scale;
			break;
		case 50:
			start_angle = data.toDouble();
			break;
		case 51:
			stop_angle = data.toDouble();
			break;
		case 70:
			dimtype = data.toInt();
			break;
		}
	}

	QHashIterator<QString, int> i(unsupported_entities_list);
	while (i.hasNext()) {
		i.next();
		if (layername.isNull()) {
			PRINTA("WARNING: Unsupported DXF Entity `%1' (%2x) in `%3'.",
					i.key(), QString::number(i.value()), filename);
		} else {
			PRINTA("WARNING: Unsupported DXF Entity `%1' (%2x) in layer `%3' of `%4'.",
					i.key(), QString::number(i.value()), layername, filename);
		}
	}

	QHash<int, int> enabled_lines;
	for (int i = 0; i < lines.count(); i++) {
		enabled_lines[i] = i;
	}

	// extract all open paths
	while (enabled_lines.count() > 0)
	{
		int current_line, current_point;

		foreach (int i, enabled_lines) {
			for (int j = 0; j < 2; j++) {
				QVector<int> *lv = &grid.data(lines[i].p[j]->x, lines[i].p[j]->y);
				for (int ki = 0; ki < lv->count(); ki++) {
					int k = lv->at(ki);
					if (k == i || lines[k].disabled)
						continue;
					goto next_open_path_j;
				}
				current_line = i;
				current_point = j;
				goto create_open_path;
			next_open_path_j:;
			}
		}

		break;

	create_open_path:
		paths.append(Path());
		Path *this_path = &paths.last();

		this_path->points.append(lines[current_line].p[current_point]);
		while (1) {
			this_path->points.append(lines[current_line].p[!current_point]);
			Point *ref_point = lines[current_line].p[!current_point];
			lines[current_line].disabled = true;
			enabled_lines.remove(current_line);
			QVector<int> *lv = &grid.data(ref_point->x, ref_point->y);
			for (int ki = 0; ki < lv->count(); ki++) {
				int k = lv->at(ki);
				if (lines[k].disabled)
					continue;
				if (grid.eq(ref_point->x, ref_point->y, lines[k].p[0]->x, lines[k].p[0]->y)) {
					current_line = k;
					current_point = 0;
					goto found_next_line_in_open_path;
				}
				if (grid.eq(ref_point->x, ref_point->y, lines[k].p[1]->x, lines[k].p[1]->y)) {
					current_line = k;
					current_point = 1;
					goto found_next_line_in_open_path;
				}
			}
			break;
		found_next_line_in_open_path:;
		}
	}

	// extract all closed paths
	while (enabled_lines.count() > 0)
	{
		int current_line = enabled_lines.begin().value(), current_point = 0;

		paths.append(Path());
		Path *this_path = &paths.last();
		this_path->is_closed = true;
		
		this_path->points.append(lines[current_line].p[current_point]);
		while (1) {
			this_path->points.append(lines[current_line].p[!current_point]);
			Point *ref_point = lines[current_line].p[!current_point];
			lines[current_line].disabled = true;
			enabled_lines.remove(current_line);
			QVector<int> *lv = &grid.data(ref_point->x, ref_point->y);
			for (int ki = 0; ki < lv->count(); ki++) {
				int k = lv->at(ki);
				if (lines[k].disabled)
					continue;
				if (grid.eq(ref_point->x, ref_point->y, lines[k].p[0]->x, lines[k].p[0]->y)) {
					current_line = k;
					current_point = 0;
					goto found_next_line_in_closed_path;
				}
				if (grid.eq(ref_point->x, ref_point->y, lines[k].p[1]->x, lines[k].p[1]->y)) {
					current_line = k;
					current_point = 1;
					goto found_next_line_in_closed_path;
				}
			}
			break;
		found_next_line_in_closed_path:;
		}
	}

	if (paths.count() > 0) {
		for (int i = 0; i < paths.count(); i++) {
			if (!paths[i].is_closed)
				break;
			paths[i].is_inner = true;
			double min_x = paths[i].points[0]->x;
			int min_x_point = 0;
			for (int j = 0; j < paths[i].points.count(); j++) {
				if (paths[i].points[j]->x < min_x) {
					min_x = paths[i].points[j]->x;
					min_x_point = j;
				}
			}
			// rotate points if the path is in non-standard rotation
			int b = min_x_point;
			int a = b == 0 ? paths[i].points.count() - 2 : b - 1;
			int c = b == paths[i].points.count() - 1 ? 1 : b + 1;
			double ax = paths[i].points[a]->x - paths[i].points[b]->x;
			double ay = paths[i].points[a]->y - paths[i].points[b]->y;
			double cx = paths[i].points[c]->x - paths[i].points[b]->x;
			double cy = paths[i].points[c]->y - paths[i].points[b]->y;
#if 0
			printf("Rotate check:\n");
			printf("  a/b/c indices = %d %d %d\n", a, b, c);
			printf("  b->a vector = %f %f (%f)\n", ax, ay, atan2(ax, ay));
			printf("  b->c vector = %f %f (%f)\n", cx, cy, atan2(cx, cy));
#endif
			if (atan2(ax, ay) < atan2(cx, cy)) {
				for (int j = 0; j < paths[i].points.count()/2; j++)
					paths[i].points.swap(j, paths[i].points.count()-1-j);
			}
		}
	}

#if 0
	printf("----- DXF Data -----\n");
	for (int i = 0; i < paths.count(); i++) {
		printf("Path %d (%s):\n", i, paths[i].is_closed ? "closed" : "open");
		for (int j = 0; j < paths[i].points.count(); j++)
			printf("  %f %f\n", paths[i].points[j]->x, paths[i].points[j]->y);
	}
	printf("--------------------\n");
	fflush(stdout);
#endif
}

DxfData::Point *DxfData::p(double x, double y)
{
	points.append(Point(x, y));
	return &points.last();
}