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(undo_object_t *obj) {
  char *msg = osm_object_string(obj->type, obj->data.ptr);
  printf("   object %s\n", msg);
  g_free(msg);

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

    case WAY:
      osm_way_free(obj->data.way);
      break;
      
    default:
      printf("ERROR: unsupported object %s\n", 
             osm_type_string(obj->type));
      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 undo_object_t *undo_object_copy(type_t type, void *object) {
  switch(type) {
  case NODE: {
    undo_object_t *ob = g_new0(undo_object_t, 1);
    ob->type = type;

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

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

    return ob;
    } break;

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

    /* fields ignored in this copy operation: */

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

    return ob;
    } break;

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

  return NULL;
}

void undo_remember_delete(appdata_t *appdata, type_t type, 
                          void *object) {

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

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

  /* 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(type, object);
}

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

  char *msg = osm_object_string(obj->type, obj->data.ptr);
  printf("UNDO deletion of object %s\n", msg);
  g_free(msg);
  
  switch(obj->type) {
  case NODE: {
    node_t *node = obj->data.node;

    /* there must be an "deleted" entry which needs to be */
    /* removed */
    node_t *orig = osm_get_node_by_id(appdata->osm, 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(node);
    osm_node_restore(appdata->osm, node);
    josm_elemstyles_colorize_node(appdata->map->style, node);
    map_node_draw(appdata->map, node);
    obj->data.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	/*
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	/* 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	static void undo_object_free(undo_object_t *obj) {
40	char *msg = osm_object_string(obj->type, obj->data.ptr);
41	printf(" object %s\n", msg);
42	g_free(msg);
43
44	if(obj->data.ptr) {
45	switch(obj->type) {
46	case NODE:
47	osm_node_free(NULL, obj->data.node);
48	break;
49
50	case WAY:
51	osm_way_free(obj->data.way);
52	break;
53
54	default:
55	printf("ERROR: unsupported object %s\n",
56	osm_type_string(obj->type));
57	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	static void undo_state_free(undo_state_t *state) {
72	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	g_free(state);
82	}
83
84	/* free all undo states, thus forgetting the entire history */
85	/* called at program exit or e.g. at project change */
86	void undo_free(undo_state_t *state) {
87	printf("Freeing all UNDO states:\n");
88
89	while(state) {
90	undo_state_t *next = state->next;
91	undo_state_free(state);
92	state = next;
93	}
94	}
95
96	/* append a new state to the chain of undo states */
97	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	undo_state_t **undo_stateP = &appdata->undo.state;
103	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	undo_state_t *second = appdata->undo.state->next;
114	undo_state_free(appdata->undo.state);
115	appdata->undo.state = second;
116	}
117
118	printf("UNDO: current chain length = %d\n", undo_chain_length);
119
120	return new_state;
121	}
122
123	/* create a local copy of the entire object */
124	static undo_object_t undo_object_copy(type_t type, void object) {
125	switch(type) {
126	case NODE: {
127	undo_object_t *ob = g_new0(undo_object_t, 1);
128	ob->type = type;
129
130	/* fields ignored in this copy operation: */
131	/* ways, icon_buf, map_item_chain, next */
132
133	node_t node = (node_t)object;
134	ob->data.node = g_new0(node_t, 1);
135	/* copy all important parts, omitting icon pointers etc. */
136	ob->data.node->id = node->id;
137	ob->data.node->lpos = node->lpos;
138	ob->data.node->pos = node->pos;
139	/* user is a pointer, but since the users list */
140	/* is never touched it's ok */
141	ob->data.node->user = node->user;
142	ob->data.node->visible = node->visible;
143	ob->data.node->time = node->time;
144	ob->data.node->tag = osm_tags_copy(node->tag, FALSE);
145	ob->data.node->flags = node->flags;
146	ob->data.node->zoom_max = node->zoom_max;
147
148	return ob;
149	} break;
150
151	case WAY: {
152	undo_object_t *ob = g_new0(undo_object_t, 1);
153	ob->type = type;
154
155	/* fields ignored in this copy operation: */
156
157	way_t way = (way_t)object;
158	ob->data.way = g_new0(way_t, 1);
159	/* copy all important parts */
160	ob->data.way->id = way->id;
161	/* user is a pointer, but since the users list */
162	/* is never touched it's ok */
163	ob->data.way->user = way->user;
164	ob->data.way->visible = way->visible;
165	ob->data.way->time = way->time;
166	ob->data.way->tag = osm_tags_copy(way->tag, FALSE);
167	ob->data.way->flags = way->flags;
168
169	return ob;
170	} break;
171
172	default:
173	printf("UNDO WARNING: ignoring unsupported object %s\n",
174	osm_type_string(type));
175	break;
176	}
177
178	return NULL;
179	}
180
181	void undo_remember_delete(appdata_t *appdata, type_t type,
182	void *object) {
183
184	/* don't do anything if undo isn't enabled */
185	if(!appdata->menu_item_osm_undo)
186	return;
187
188	printf("UNDO: remembering delete operation for %s\n",
189	osm_type_string(type));
190
191	/* create a new undo state */
192	undo_state_t *state = undo_append_state(appdata);
193	state->type = UNDO_DELETE;
194
195	/* a simple stand-alone node deletion is just a single */
196	/* operation on the database/map so only one undo_op is saved */
197	undo_op_t *op = state->op = g_new0(undo_op_t, 1);
198	op->type = UNDO_DELETE;
199	op->object = undo_object_copy(type, object);
200	}
201
202	/* undo the deletion of an object */
203	static void undo_operation_object_delete(appdata_t *appdata,
204	undo_object_t *obj) {
205
206	char *msg = osm_object_string(obj->type, obj->data.ptr);
207	printf("UNDO deletion of object %s\n", msg);
208	g_free(msg);
209
210	switch(obj->type) {
211	case NODE: {
212	node_t *node = obj->data.node;
213
214	/* there must be an "deleted" entry which needs to be */
215	/* removed */
216	node_t *orig = osm_get_node_by_id(appdata->osm, node->id);
217	g_assert(orig);
218	g_assert(orig->flags & OSM_FLAG_DELETED);
219	way_chain_t *wchain =
220	osm_node_delete(appdata->osm, &appdata->icon, orig, TRUE, TRUE);
221	g_assert(!wchain);
222
223	/* then restore old node */
224	osm_node_dump(node);
225	osm_node_restore(appdata->osm, node);
226	josm_elemstyles_colorize_node(appdata->map->style, node);
227	map_node_draw(appdata->map, node);
228	obj->data.ptr = NULL;
229	} break;
230
231	default:
232	printf("Unsupported object type\n");
233	break;
234	}
235	}
236
237	/* undo a single operation */
238	static void undo_operation(appdata_t appdata, undo_op_t op) {
239	printf("UNDO operation: %s\n", undo_type_string(op->type));
240
241	switch(op->type) {
242	case UNDO_DELETE:
243	undo_operation_object_delete(appdata, op->object);
244	break;
245
246	default:
247	printf("unsupported UNDO operation\n");
248	g_assert(0);
249	break;
250	}
251	}
252
253	/* undo the last undo_state */
254	void undo(appdata_t *appdata) {
255	undo_state_t *state = appdata->undo.state;
256	printf("user selected undo\n");
257
258	/* search last (newest) entry */
259	while(state && state->next) state = state->next;
260
261	if(!state) {
262	banner_show_info(appdata, _("No further undo data"));
263	return;
264	}
265
266
267	printf("UNDO state: %s\n", undo_type_string(state->type));
268
269	/* since the operations list was built by prepending new */
270	/* entries, just going through the list will run the operations */
271	/* in reverse order. That's exactly what we want! */
272
273	undo_op_t *op = state->op;
274	while(op) {
275	undo_operation(appdata, op);
276	op = op->next;
277	}
278
279	/* remove this entry from chain */
280	undo_state_t **stateP = &appdata->undo.state;
281	while(stateP && (stateP)->next) stateP = &(*stateP)->next;
282
283	undo_state_free(*stateP);
284	*stateP = NULL;
285	}