/*
 * lib.c - Parse Eeschema .lib file
 *
 * Written 2016 by Werner Almesberger
 * Copyright 2016 by Werner Almesberger
 *
 * 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.
 */


#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>

#include "style.h"
#include "fig.h"
#include "text.h"
#include "lib.h"


enum text_style {
	text_normal,
};

struct obj {
	enum obj_type {
		obj_poly,
		obj_rect,
		obj_circ,
		obj_arc,
		obj_text,
		obj_pin,
	} type;
	unsigned unit;
	unsigned convert;
	union {
		struct poly {
			int thick;
			char fill;
			int points;
			int *x;
			int *y;
		} poly;
		struct {
			int thick;
			char fill;
			int sx, sy;
			int ex, ey;
		} rect;
		struct {
			int x, y;
			int r;
			int thick;
			char fill;
		} circ;
		struct text_obj {
			int orient;
			int x, y;
			int dim;
			char *s;
			enum text_style style;
			char hor_align;
			char vert_align;
		} text;
		struct pin_obj {
			char *name;
			char *number;
			int x, y;
			int length;
			char orient;
			int number_size;
			int name_size;
			char etype;
			// @@@ shape
		} pin;
	} u;
	struct obj *next;
};


struct comp {
	const char *name;
	struct obj *objs;
	struct comp *next;
};


static struct comp *comps = NULL;
static struct comp **next_comp = &comps;
static struct obj **next_obj;


static inline int mx(int x, int y, int m[6])
{
	return m[0] + x * m[1] + y * m[2];
}


static inline int my(int x, int y, int m[6])
{
	return m[3] + x * m[4] + y * m[5];
}


static void draw_poly(const struct poly *poly, int m[6])
{
	int n = poly->points;
	int x[n];
	int y[n];
	int i;

	for (i = 0; i != n; i++) {
		x[i] = mx(poly->x[i], poly->y[i], m);
		y[i] = my(poly->x[i], poly->y[i], m);
	}
	fig_poly(n, x, y);
}


static void draw_pin(const struct pin_obj *pin, int m[6])
{
	int x[2], y[2];
	int dx = 0, dy = 0;

	switch (pin->orient) {
	case 'U':
		dy = pin->length;
		break;
	case 'D':
		dy = -pin->length;
		break;
	case 'R':
		dx = pin->length;
		break;
	case 'L':
		dx = -pin->length;
		break;
	default:
		abort();
	}
	x[0] = mx(pin->x, pin->y, m);
	y[0] = my(pin->x, pin->y, m);
	x[1] = mx(pin->x + dx, pin->y + dy, m);
	y[1] = my(pin->x + dx, pin->y + dy, m);
	fig_poly(2, x, y);
}


static bool eq(int m[6], int xx, int xy, int yx, int yy)
{
	return m[1] == xx && m[2] == xy && m[4] == yx && m[5] == yy;
}


static unsigned matrix_to_angle(int m[6])
{
	if (eq(m, 1, 0, 0, -1))
		return 0;
	if (eq(m, 0, -1, -1, 0))
		return 90;
	if (eq(m, 0, 1, 1, 0))
		return 270;
	fprintf(stderr, "unrecognized matrix %d %d %d %d\n",
	    m[1], m[2], m[4], m[5]);
	exit(1);
}


static void draw_text(const struct text_obj *text, int m[6])
{
	struct text txt = {
		.s = text->s,
		.size = text->dim,
		.x = mx(text->x, text->y, m),
		.y = my(text->x, text->y, m),
		.rot = matrix_to_angle(m),
		.hor = text_mid,
		.vert = text_mid,
	};
	text_fig(&txt, COLOR_COMP_DWG, WIDTH_COMP_DWG);
}


static void draw(const struct obj *obj, int m[6])
{
	switch (obj->type) {
	case obj_poly:
		draw_poly(&obj->u.poly, m);
		break;
	case obj_rect:
		fig_rect(mx(obj->u.rect.sx, obj->u.rect.sy, m),
		    my(obj->u.rect.sx, obj->u.rect.sy, m),
		    mx(obj->u.rect.ex, obj->u.rect.ey, m),
		    my(obj->u.rect.ex, obj->u.rect.ey, m));
		    // @@@
		break;
	case obj_circ:
		break;
	case obj_arc:
		break;
	case obj_text:
		draw_text(&obj->u.text, m);
		break;
	case obj_pin:
		draw_pin(&obj->u.pin, m);
		break;
	default:
		abort();
	}
}


void lib_exec(const char *name, unsigned unit, int m[4])
{
	const struct comp *comp;
	const struct obj *obj;

	for (comp = comps; comp; comp = comp->next)
		if (!strcmp(comp->name, name))
			goto found;
	fprintf(stderr, "\"%s\" not found\n", name);
	exit(1);

found:
	for (obj = comp->objs; obj; obj = obj->next) {
		if (obj->unit && obj->unit != unit)
			continue;
		draw(obj, m);
	}
}


static enum text_style decode_style(const char *s)
{
	if (!strcmp(s, "Normal"))
		return text_normal;
	abort();
}


static bool parse_poly(struct obj *obj, const char *line, int points)
{
	int i, n;

	obj->u.poly.points = points;
	obj->u.poly.x = malloc(sizeof(int) * points);
	obj->u.poly.y = malloc(sizeof(int) * points);
	for (i = 0; i != points; i++) {
		if (sscanf(line, "%d %d %n",
		    obj->u.poly.x + i, obj->u.poly.y + i, &n) != 2)
			return 0;
		line += n;
	}
	if (sscanf(line, "%c", &obj->u.poly.fill) != 1)
		return 0;
	return 1;
}


bool lib_parse(struct lib_ctx *ctx, const char *line)
{
	int n = 0;
	char *s;
	unsigned points;
	struct comp *comp;
	struct obj *obj;
	char *style;
	unsigned zero1, zero2;

	ctx->lineno++;

	switch (ctx->state) {
	case lib_skip:
		if (sscanf(line, "DEF %ms", &s) == 1) {
			ctx->state = lib_def;
			comp = malloc(sizeof(struct comp));
			if (*s == '~')
				s++;
			comp->name = s;
			comp->objs = NULL;
			comp->next = NULL;
			*next_comp = comp;
			next_comp = &comp->next;
			next_obj = &comp->objs;
			return 1;
		}
		return 1;
	case lib_def:
		if (sscanf(line, "DRAW%n", &n) == 0 && n) {
			ctx->state = lib_draw;
			return 1;
		}
		return 1;
	case lib_draw:
		if (sscanf(line, "ENDDRAW%n", &n) == 0 && n) {
			ctx->state = lib_skip;
			return 1;
		}

		obj = malloc(sizeof(struct obj));
		obj->next = NULL;
		*next_obj = obj;
		next_obj = &obj->next;

		if (sscanf(line, "P %u %u %u %u %n",
		    &points, &obj->unit, &obj->convert, &obj->u.poly.thick,
		    &n) == 4) {
			obj->type = obj_poly;
			if (parse_poly(obj, line + n, points))
				return 1;
			break;
		}
		if (sscanf(line, "S %d %d %d %d %u %u %d %c",
		    &obj->u.rect.sx, &obj->u.rect.sy, &obj->u.rect.ex,
		    &obj->u.rect.ey, &obj->unit, &obj->convert,
		    &obj->u.rect.thick, &obj->u.rect.fill) == 8) {
			obj->type = obj_rect;
			return 1;
		}
		if (sscanf(line, "C %d %d %d %u %u %d %c",
		    &obj->u.circ.x, &obj->u.circ.y, &obj->u.circ.r,
		    &obj->unit, &obj->convert, &obj->u.circ.thick,
		    &obj->u.circ.fill) == 7) {
			obj->type = obj_circ;
			return 1;
		}
		if (sscanf(line, "A %n", &n) == 0 && n) {
			obj->type = obj_arc;
			return 1; // @@@
		}
		n = sscanf(line,
		    "T %d %d %d %d %u %u %u \"%m[^\"]\" %ms %u %c %c",
		    &obj->u.text.orient, &obj->u.text.x, &obj->u.text.y,
		    &obj->u.text.dim, &zero1, &obj->unit, &obj->convert,
		    &obj->u.text.s, &style, &zero2,
		    &obj->u.text.hor_align, &obj->u.text.vert_align);
		if (n != 12)
			n = sscanf(line,
			    "T %d %d %d %d %u %u %u %ms %ms %u %c %c",
			    &obj->u.text.orient, &obj->u.text.x, &obj->u.text.y,
			    &obj->u.text.dim, &zero1, &obj->unit, &obj->convert,
			    &obj->u.text.s, &style, &zero2,
			    &obj->u.text.hor_align, &obj->u.text.vert_align);
		if (n == 12) {
			if (zero1 || zero2) {
				fprintf(stderr, "%u: only understand 0 x x\n",
				    ctx->lineno);
				exit(1);
			}
			obj->u.text.style = decode_style(style);
			obj->type = obj_text;
			return 1;
		}
		if (sscanf(line, "X %ms %ms %d %d %d %c %d %d %u %u %c",
		    &obj->u.pin.name, &obj->u.pin.number, 
		    &obj->u.pin.x, &obj->u.pin.y, &obj->u.pin.length,
		    &obj->u.pin.orient,
		    &obj->u.pin.number_size, &obj->u.pin.name_size,
		    &obj->unit, &obj->convert, &obj->u.pin.etype) == 11) {
			obj->type = obj_pin;
			return 1;
		}
		break;
	default:
		abort();
	}
	fprintf(stderr, "%u: cannot parse\n\"%s\"\n", ctx->lineno, line);
	exit(1);
}


void lib_init(struct lib_ctx *ctx)
{
	ctx->state = lib_skip;
	ctx->lineno = 0;
}