trunk/src/undo.c

/*
 * Copyright (C) 2008 Till Harbaum <till@harbaum.org>.
 *
 * This file is part of OSM2Go.
 *
 * OSM2Go 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 3 of the License, or
 * (at your option) any later version.
 *
 * OSM2Go 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 OSM2Go.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "appdata.h"

/* return plain text of type */
char *undo_type_string(type_t type) {
  const struct { undo_type_t type; char *name; } types[] = {
    { UNDO_DELETE, "DELETE" },
    { UNDO_CREATE, "CREATE" },
    { UNDO_MODIFY, "MODIFY" },
    { 0, NULL }
  };

  int i;
  for(i=0;types[i].name;i++) 
    if(type == types[i].type)
      return types[i].name;

  return NULL;
}

static void undo_object_free(object_t *obj) {
  char *msg = osm_object_string(obj);
  printf("   object %s\n", msg);
  g_free(msg);

  if(obj->ptr) {
    switch(obj->type) {
    case NODE:
      osm_node_free(NULL, obj->node);
      break;

    case WAY:
      osm_way_free(obj->way);
      break;
      
    default:
      printf("ERROR: unsupported object %s\n", 
             osm_object_type_string(obj));
      g_assert(0);
      break;
    }
  }

  g_free(obj);
}

static void undo_op_free(undo_op_t *op) {
  printf("  op: %s\n", undo_type_string(op->type));
  if(op->object) undo_object_free(op->object);
  g_free(op);
}

static void undo_state_free(undo_state_t *state) {
  printf(" state: %s\n", undo_type_string(state->type));

  undo_op_t *op = state->op;
  while(op) {
    undo_op_t *next = op->next;
    undo_op_free(op);
    op = next;
  }

  g_free(state);
}

/* free all undo states, thus forgetting the entire history */
/* called at program exit or e.g. at project change */
void undo_free(undo_state_t *state) {
  printf("Freeing all UNDO states:\n");

  while(state) {
    undo_state_t *next = state->next;
    undo_state_free(state);
    state = next;
  }
}

/* append a new state to the chain of undo states */
static undo_state_t *undo_append_state(appdata_t *appdata) {
  undo_state_t *new_state = NULL;

  /* create new undo state at end of undo chain */
  int undo_chain_length = 0;
  undo_state_t **undo_stateP = &appdata->undo.state;
  while(*undo_stateP) {
    undo_chain_length++;
    undo_stateP = &(*undo_stateP)->next;
  }

  /* append new entry to chain */
  new_state = *undo_stateP = g_new0(undo_state_t, 1);

  /* delete first entry if the chain is too long */
  if(undo_chain_length >= UNDO_QUEUE_LEN) {
    undo_state_t *second = appdata->undo.state->next;
    undo_state_free(appdata->undo.state);
    appdata->undo.state = second;
  }

  printf("UNDO: current chain length = %d\n", undo_chain_length);

  return new_state;
}

/* create a local copy of the entire object */
static object_t *undo_object_copy(object_t *object) {
  switch(object->type) {
  case NODE: {
    object_t *ob = g_new0(object_t, 1);
    ob->type = object->type;

    /* fields ignored in this copy operation: */
    /* ways, icon_buf, map_item_chain, next */

    ob->node = g_new0(node_t, 1);
    /* copy all important parts, omitting icon pointers etc. */
    ob->node->id = object->node->id;
    ob->node->lpos = object->node->lpos;
    ob->node->pos = object->node->pos;
    /* user is a pointer, but since the users list */
    /* is never touched it's ok */
    ob->node->user = object->node->user;
    ob->node->visible = object->node->visible;
    ob->node->time = object->node->time;
    ob->node->tag = osm_tags_copy(object->node->tag);
    ob->node->flags = object->node->flags; 
    ob->node->zoom_max = object->node->zoom_max; 

    return ob;
    } break;

  case WAY: {
    object_t *ob = g_new0(object_t, 1);
    ob->type = object->type;

    /* fields ignored in this copy operation: */

    ob->way = g_new0(way_t, 1);
    /* copy all important parts */
    ob->way->id = object->way->id;
    /* user is a pointer, but since the users list */
    /* is never touched it's ok */
    ob->way->user = object->way->user;
    ob->way->visible = object->way->visible;
    ob->way->time = object->way->time;
    ob->way->tag = osm_tags_copy(object->way->tag);
    ob->way->flags = object->way->flags; 

    return ob;
    } break;

  default:
    printf("UNDO WARNING: ignoring unsupported object %s\n", 
           osm_object_type_string(object));
    break;
  }

  return NULL;
}

void undo_remember_delete(appdata_t *appdata, object_t *object) {

  /* don't do anything if undo isn't enabled */
  if(!appdata->menu_item_map_undo)
    return;

  printf("UNDO: remembering delete operation for %s\n", 
         osm_object_type_string(object));

  /* create a new undo state */
  undo_state_t *state = undo_append_state(appdata);
  state->type = UNDO_DELETE;

  /* a simple stand-alone node deletion is just a single */
  /* operation on the database/map so only one undo_op is saved */
  undo_op_t *op = state->op = g_new0(undo_op_t, 1);
  op->type = UNDO_DELETE;
  op->object = undo_object_copy(object);
}

/* undo the deletion of an object */
static void undo_operation_object_delete(appdata_t *appdata, object_t *obj) {

  char *msg = osm_object_string(obj);
  printf("UNDO deletion of object %s\n", msg);
  g_free(msg);
  
  switch(obj->type) {
  case NODE: {
    /* there must be an "deleted" entry which needs to be */
    /* removed */
    node_t *orig = osm_get_node_by_id(appdata->osm, obj->node->id);
    g_assert(orig);
    g_assert(orig->flags & OSM_FLAG_DELETED);
    way_chain_t *wchain = 
      osm_node_delete(appdata->osm, &appdata->icon, orig, TRUE, TRUE);
    g_assert(!wchain);

    /* then restore old node */
    osm_node_dump(obj->node);
    osm_node_restore(appdata->osm, obj->node);
    josm_elemstyles_colorize_node(appdata->map->style, obj->node);
    map_node_draw(appdata->map, obj->node);
    obj->ptr = NULL;
  } break;

  default:
    printf("Unsupported object type\n");
    break;
  }
}

/* undo a single operation */
static void undo_operation(appdata_t *appdata, undo_op_t *op) {
  printf("UNDO operation: %s\n", undo_type_string(op->type));

  switch(op->type) {
  case UNDO_DELETE:
    undo_operation_object_delete(appdata, op->object);
    break;

  default:
    printf("unsupported UNDO operation\n");
    g_assert(0);
    break;
  }
}

/* undo the last undo_state */
void undo(appdata_t *appdata) {
  undo_state_t *state = appdata->undo.state;
  printf("user selected undo\n");

  /* search last (newest) entry */
  while(state && state->next) state = state->next;

  if(!state) {
    banner_show_info(appdata, _("No further undo data"));
    return;
  }

  
  printf("UNDO state: %s\n", undo_type_string(state->type));

  /* since the operations list was built by prepending new */
  /* entries, just going through the list will run the operations */
  /* in reverse order. That's exactly what we want! */

  undo_op_t *op = state->op;
  while(op) {
    undo_operation(appdata, op);
    op = op->next;
  }

  /* remove this entry from chain */
  undo_state_t **stateP = &appdata->undo.state;
  while(*stateP && (*stateP)->next) stateP = &(*stateP)->next;

  undo_state_free(*stateP);
  *stateP = NULL;
}
1	harbaum	54	/*
2			* Copyright (C) 2008 Till Harbaum <till@harbaum.org>.
3			*
4			* This file is part of OSM2Go.
5			*
6			* OSM2Go is free software: you can redistribute it and/or modify
7			* it under the terms of the GNU General Public License as published by
8			* the Free Software Foundation, either version 3 of the License, or
9			* (at your option) any later version.
10			*
11			* OSM2Go is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			* GNU General Public License for more details.
15			*
16			* You should have received a copy of the GNU General Public License
17			* along with OSM2Go. If not, see <http://www.gnu.org/licenses/>.
18			*/
19
20			#include "appdata.h"
21
22	harbaum	64	/* return plain text of type */
23			char *undo_type_string(type_t type) {
24			const struct { undo_type_t type; char *name; } types[] = {
25			{ UNDO_DELETE, "DELETE" },
26			{ UNDO_CREATE, "CREATE" },
27			{ UNDO_MODIFY, "MODIFY" },
28			{ 0, NULL }
29			};
30
31			int i;
32			for(i=0;types[i].name;i++)
33			if(type == types[i].type)
34			return types[i].name;
35
36			return NULL;
37			}
38
39	harbaum	155	static void undo_object_free(object_t *obj) {
40			char *msg = osm_object_string(obj);
41	harbaum	64	printf(" object %s\n", msg);
42			g_free(msg);
43
44	harbaum	155	if(obj->ptr) {
45	harbaum	64	switch(obj->type) {
46			case NODE:
47	harbaum	155	osm_node_free(NULL, obj->node);
48	harbaum	64	break;
49	harbaum	69
50			case WAY:
51	harbaum	155	osm_way_free(obj->way);
52	harbaum	69	break;
53	harbaum	64
54			default:
55			printf("ERROR: unsupported object %s\n",
56	harbaum	155	osm_object_type_string(obj));
57	harbaum	64	g_assert(0);
58			break;
59			}
60			}
61
62			g_free(obj);
63			}
64
65			static void undo_op_free(undo_op_t *op) {
66			printf(" op: %s\n", undo_type_string(op->type));
67			if(op->object) undo_object_free(op->object);
68			g_free(op);
69			}
70
71	harbaum	54	static void undo_state_free(undo_state_t *state) {
72	harbaum	64	printf(" state: %s\n", undo_type_string(state->type));
73
74			undo_op_t *op = state->op;
75			while(op) {
76			undo_op_t *next = op->next;
77			undo_op_free(op);
78			op = next;
79			}
80
81	harbaum	54	g_free(state);
82			}
83
84	harbaum	64	/* free all undo states, thus forgetting the entire history */
85			/* called at program exit or e.g. at project change */
86	harbaum	54	void undo_free(undo_state_t *state) {
87	harbaum	64	printf("Freeing all UNDO states:\n");
88
89	harbaum	54	while(state) {
90			undo_state_t *next = state->next;
91			undo_state_free(state);
92			state = next;
93			}
94			}
95
96	harbaum	64	/* append a new state to the chain of undo states */
97	harbaum	54	static undo_state_t undo_append_state(appdata_t appdata) {
98			undo_state_t *new_state = NULL;
99
100			/* create new undo state at end of undo chain */
101			int undo_chain_length = 0;
102	harbaum	68	undo_state_t **undo_stateP = &appdata->undo.state;
103	harbaum	54	while(*undo_stateP) {
104			undo_chain_length++;
105			undo_stateP = &(*undo_stateP)->next;
106			}
107
108			/* append new entry to chain */
109			new_state = *undo_stateP = g_new0(undo_state_t, 1);
110
111			/* delete first entry if the chain is too long */
112			if(undo_chain_length >= UNDO_QUEUE_LEN) {
113	harbaum	68	undo_state_t *second = appdata->undo.state->next;
114			undo_state_free(appdata->undo.state);
115			appdata->undo.state = second;
116	harbaum	54	}
117
118			printf("UNDO: current chain length = %d\n", undo_chain_length);
119
120			return new_state;
121			}
122
123	harbaum	64	/* create a local copy of the entire object */
124	harbaum	155	static object_t undo_object_copy(object_t object) {
125			switch(object->type) {
126	harbaum	64	case NODE: {
127	harbaum	155	object_t *ob = g_new0(object_t, 1);
128			ob->type = object->type;
129	harbaum	69
130	harbaum	64	/* fields ignored in this copy operation: */
131			/* ways, icon_buf, map_item_chain, next */
132
133	harbaum	155	ob->node = g_new0(node_t, 1);
134	harbaum	64	/* copy all important parts, omitting icon pointers etc. */
135	harbaum	155	ob->node->id = object->node->id;
136			ob->node->lpos = object->node->lpos;
137			ob->node->pos = object->node->pos;
138	harbaum	64	/* user is a pointer, but since the users list */
139			/* is never touched it's ok */
140	harbaum	155	ob->node->user = object->node->user;
141			ob->node->visible = object->node->visible;
142			ob->node->time = object->node->time;
143	harbaum	234	ob->node->tag = osm_tags_copy(object->node->tag);
144	harbaum	155	ob->node->flags = object->node->flags;
145			ob->node->zoom_max = object->node->zoom_max;
146	harbaum	69
147			return ob;
148	harbaum	64	} break;
149
150	harbaum	69	case WAY: {
151	harbaum	155	object_t *ob = g_new0(object_t, 1);
152			ob->type = object->type;
153	harbaum	69
154			/* fields ignored in this copy operation: */
155
156	harbaum	155	ob->way = g_new0(way_t, 1);
157	harbaum	69	/* copy all important parts */
158	harbaum	155	ob->way->id = object->way->id;
159	harbaum	69	/* user is a pointer, but since the users list */
160			/* is never touched it's ok */
161	harbaum	155	ob->way->user = object->way->user;
162			ob->way->visible = object->way->visible;
163			ob->way->time = object->way->time;
164	harbaum	234	ob->way->tag = osm_tags_copy(object->way->tag);
165	harbaum	155	ob->way->flags = object->way->flags;
166	harbaum	69
167			return ob;
168			} break;
169
170	harbaum	64	default:
171	harbaum	69	printf("UNDO WARNING: ignoring unsupported object %s\n",
172	harbaum	155	osm_object_type_string(object));
173	harbaum	64	break;
174			}
175
176	harbaum	69	return NULL;
177	harbaum	64	}
178
179	harbaum	155	void undo_remember_delete(appdata_t appdata, object_t object) {
180	harbaum	69
181			/* don't do anything if undo isn't enabled */
182	harbaum	188	if(!appdata->menu_item_map_undo)
183	harbaum	69	return;
184
185	harbaum	64	printf("UNDO: remembering delete operation for %s\n",
186	harbaum	155	osm_object_type_string(object));
187	harbaum	64
188			/* create a new undo state */
189	harbaum	54	undo_state_t *state = undo_append_state(appdata);
190	harbaum	64	state->type = UNDO_DELETE;
191	harbaum	54
192	harbaum	64	/* a simple stand-alone node deletion is just a single */
193			/* operation on the database/map so only one undo_op is saved */
194			undo_op_t *op = state->op = g_new0(undo_op_t, 1);
195			op->type = UNDO_DELETE;
196	harbaum	155	op->object = undo_object_copy(object);
197	harbaum	54	}
198	harbaum	64
199			/* undo the deletion of an object */
200	harbaum	155	static void undo_operation_object_delete(appdata_t appdata, object_t obj) {
201	harbaum	64
202	harbaum	155	char *msg = osm_object_string(obj);
203	harbaum	64	printf("UNDO deletion of object %s\n", msg);
204			g_free(msg);
205
206			switch(obj->type) {
207			case NODE: {
208			/* there must be an "deleted" entry which needs to be */
209			/* removed */
210	harbaum	155	node_t *orig = osm_get_node_by_id(appdata->osm, obj->node->id);
211	harbaum	64	g_assert(orig);
212			g_assert(orig->flags & OSM_FLAG_DELETED);
213			way_chain_t *wchain =
214	harbaum	68	osm_node_delete(appdata->osm, &appdata->icon, orig, TRUE, TRUE);
215	harbaum	64	g_assert(!wchain);
216
217			/* then restore old node */
218	harbaum	155	osm_node_dump(obj->node);
219			osm_node_restore(appdata->osm, obj->node);
220			josm_elemstyles_colorize_node(appdata->map->style, obj->node);
221			map_node_draw(appdata->map, obj->node);
222			obj->ptr = NULL;
223	harbaum	64	} break;
224
225			default:
226			printf("Unsupported object type\n");
227			break;
228			}
229			}
230
231			/* undo a single operation */
232			static void undo_operation(appdata_t appdata, undo_op_t op) {
233			printf("UNDO operation: %s\n", undo_type_string(op->type));
234
235			switch(op->type) {
236			case UNDO_DELETE:
237			undo_operation_object_delete(appdata, op->object);
238			break;
239
240			default:
241			printf("unsupported UNDO operation\n");
242			g_assert(0);
243			break;
244			}
245			}
246
247			/* undo the last undo_state */
248			void undo(appdata_t *appdata) {
249	harbaum	68	undo_state_t *state = appdata->undo.state;
250	harbaum	64	printf("user selected undo\n");
251
252			/* search last (newest) entry */
253			while(state && state->next) state = state->next;
254
255			if(!state) {
256			banner_show_info(appdata, _("No further undo data"));
257			return;
258			}
259
260
261			printf("UNDO state: %s\n", undo_type_string(state->type));
262
263			/* since the operations list was built by prepending new */
264			/* entries, just going through the list will run the operations */
265			/* in reverse order. That's exactly what we want! */
266
267			undo_op_t *op = state->op;
268			while(op) {
269			undo_operation(appdata, op);
270			op = op->next;
271			}
272
273			/* remove this entry from chain */
274	harbaum	68	undo_state_t **stateP = &appdata->undo.state;
275	harbaum	64	while(stateP && (stateP)->next) stateP = &(*stateP)->next;
276
277			undo_state_free(*stateP);
278			*stateP = NULL;
279			}