From fd8942c64e2e3085f510fbeecd5a671820fbb256 Mon Sep 17 00:00:00 2001
From: Trumeet <yuuta@yuuta.moe>
Date: Sun, 21 Nov 2021 18:27:38 -0800
Subject: refactor(expvc/common): support more data types using inheritance

---
 common.h | 79 ++++++++++++++++++++++++++++++++++++++++++++++++----------------
 expvc.c  | 13 ++++++-----
 2 files changed, 67 insertions(+), 25 deletions(-)

diff --git a/common.h b/common.h
index 30620fd..ead08c2 100644
--- a/common.h
+++ b/common.h
@@ -6,38 +6,79 @@
 #include <assert.h>
 #include <math.h>
 
+enum val_type { VEC3D, BOX };
+
+struct val {
+	enum val_type type;
+};
+
 struct vec3d {
+	enum val_type type;
 	double x;
 	double y;
 	double z;
 };
 
-static int vec3d_parse(char *in, struct vec3d *out)
+struct box {
+	enum val_type type;
+	double min_x;
+	double min_y;
+	double min_z;
+	double max_x;
+	double max_y;
+	double max_z;
+};
+
+static inline double *val_get_index(struct val *val, int index)
+{
+	switch (val->type)
+	{
+		case VEC3D:
+			struct vec3d *d_v3d = (struct vec3d *)val;
+			switch (index)
+			{
+				case 0: return &d_v3d->x;
+				case 1: return &d_v3d->y;
+				case 2: return &d_v3d->z;
+				default: assert(0);
+			}
+		case BOX:
+			struct box *v_box = (struct box *)val;
+			switch (index)
+			{
+				case 0: return &v_box->min_x;
+				case 1: return &v_box->min_y;
+				case 2: return &v_box->min_z;
+				case 3: return &v_box->max_x;
+				case 4: return &v_box->max_y;
+				case 5: return &v_box->max_z;
+				default: assert(0);
+			}
+		default:
+			assert(0);
+	}
+}
+
+static int val_parse(char *in, struct val *o)
 {
 	int i = 0;
 	char *p = strtok(in, ",");
+	int required_vars = 0;
+	switch (o->type)
+	{
+		case VEC3D:
+			required_vars = 3;
+			break;
+		case BOX:
+			required_vars = 6;
+			break;
+	}
 	while (p != NULL)
 	{
-		double *ptr;
-		switch (i ++)
-		{
-			case 0:
-				ptr = &out->x;
-				break;
-			case 1:
-				ptr = &out->y;
-				break;
-			case 2:
-				ptr = &out->z;
-				break;
-			default:
-				assert(0);
-				break;
-		}
-		sscanf(p, "%lf", ptr);
+		sscanf(p, "%lf", val_get_index(o, i++));
 		p = strtok(NULL, ",");
 	}
-	if (i != 3)
+	if (i != required_vars)
 	{
 		fprintf(stderr, "Invalid Vec3D: %s. Example: -1,1,1.\n", in);
 		return 64;
diff --git a/expvc.c b/expvc.c
index dc7637f..b3aa27b 100644
--- a/expvc.c
+++ b/expvc.c
@@ -8,9 +8,9 @@
 
 int main(int argc, char **argv)
 {
-	struct vec3d tnt = { 0.0, 0.0, 0.0 };
-	struct vec3d entity = { 0.0, 0.0, 0.0 };
-	struct vec3d velocity = { 0.0, 0.0, 0.0 };
+	struct vec3d tnt = { VEC3D, 0.0, 0.0, 0.0 };
+	struct vec3d entity = { VEC3D, 0.0, 0.0, 0.0 };
+	struct vec3d velocity = { VEC3D, 0.0, 0.0, 0.0 };
 	double entity_eye_y = 0.0;
 	int is_tnt = 1;
 	double power = 4.0;
@@ -44,9 +44,9 @@ usage:
 			goto usage;
 		}
 		char *val = argv[++i];
-		if (!strcmp("-t", arg)) { if ((r = vec3d_parse(val, &tnt))) return r; }
-		else if (!strcmp("-e", arg)) { if ((r = vec3d_parse(val, &entity))) return r; }
-		else if (!strcmp("-v", arg)) { if ((r = vec3d_parse(val, &velocity))) return r; }
+		if (!strcmp("-t", arg)) { if ((r = val_parse(val, (struct val *)&tnt))) return r; }
+		else if (!strcmp("-e", arg)) { if ((r = val_parse(val, (struct val *)&entity))) return r; }
+		else if (!strcmp("-v", arg)) { if ((r = val_parse(val, (struct val *)&velocity))) return r; }
 		else if (!strcmp("-ey", arg))
 		{
 			sscanf(val, "%lf", &entity_eye_y);
@@ -107,6 +107,7 @@ usage:
 	printf("DAMAGE=%d\n", damage);
 	fprintf(stderr, "WARNING: Explosion protection is ignored. In reality, if the entity has that protection, the final acceleration may be altered.\n");
 	struct vec3d delta_v = {
+		VEC3D,
 		xx * accel,
 		yy * accel,
 		zz * accel
-- 
cgit v1.2.3