2.5 filebrowser: previous/next + bugfix + elubie's changes and cleanup

* Previous/Next Folder browser
* bugfix: "open most recently opened directory".

* Previous and Next functionalities:
- use BACKSPACE to navigate to previous folders
- use SHIFT+BACKSPACE to navigate forward
- once you change the folder by other ways the forward folder list is cleared

* bug fix: the sfile->params->dir set through ED_fileselect_set_params wasn't correct. According to the code taking the settings from the existing (previous) filebrowser is a temp solution. In that case this is a fix for a temp solution :)
(changes in: wm_event_system.c, filesel.c and ED_fileselect.h)

** Andrea(elubie): we can get away of the folderlist_clear_next test if we manually pass a boolean to file_change_dir (e.g. file_change_dir(sfile, true)). I tried not to mess up with your changes here. It's slightly slower (and maybe hacky) but its's more conservative IMHO.

(my first commit to 2.5 ... that was a good reason to put my paper on hold :p)

7 files changed, 225 insertions, 29 deletions

diff --git a/source/blender/editors/include/ED_fileselect.h b/source/blender/editors/include/ED_fileselect.h
index 01882ecd9bc..1b8524eea33 100644
--- a/source/blender/editors/include/ED_fileselect.h
+++ b/source/blender/editors/include/ED_fileselect.h
@@ -69,7 +69,7 @@ typedef struct FileLayout
 
 struct FileSelectParams* ED_fileselect_get_params(struct SpaceFile *sfile);
 
-short ED_fileselect_set_params(struct SpaceFile *sfile, const char *title, const char *path, 
+short ED_fileselect_set_params(struct SpaceFile *sfile, const char *title, const char *dir, const char *path, 
 						   short flag, short display, short filter, short sort);
 
 void ED_fileselect_reset_params(struct SpaceFile *sfile);
diff --git a/source/blender/editors/space_file/file_intern.h b/source/blender/editors/space_file/file_intern.h
index 5a440be6962..2f3fae47abb 100644
--- a/source/blender/editors/space_file/file_intern.h
+++ b/source/blender/editors/space_file/file_intern.h
@@ -65,6 +65,8 @@ void FILE_OT_loadimages(struct wmOperatorType *ot);
 void FILE_OT_exec(struct wmOperatorType *ot);
 void FILE_OT_cancel(struct wmOperatorType *ot);
 void FILE_OT_parent(struct wmOperatorType *ot);
+void FILE_OT_previous(struct wmOperatorType *ot);
+void FILE_OT_next(struct wmOperatorType *ot);
 void FILE_OT_refresh(struct wmOperatorType *ot);
 void FILE_OT_bookmark_toggle(struct wmOperatorType *ot);
 void FILE_OT_filenum(struct wmOperatorType *ot);
@@ -72,11 +74,14 @@ void FILE_OT_filenum(struct wmOperatorType *ot);
 int file_exec(bContext *C, struct wmOperator *unused);
 int file_cancel_exec(bContext *C, struct wmOperator *unused);
 int file_parent_exec(bContext *C, struct wmOperator *unused);
+int file_previous_exec(bContext *C, struct wmOperator *unused);
+int file_next_exec(bContext *C, struct wmOperator *unused);
 int file_hilight_set(struct SpaceFile *sfile, struct ARegion *ar, int mx, int my);
 
 /* filesel.c */
 float file_string_width(const char* str);
 float file_font_pointsize();
+void file_change_dir(struct SpaceFile *sfile);
 
 /* file_panels.c */
 void file_panels_register(struct ARegionType *art);
diff --git a/source/blender/editors/space_file/file_ops.c b/source/blender/editors/space_file/file_ops.c
index fa377c06184..bb56ec94d7b 100644
--- a/source/blender/editors/space_file/file_ops.c
+++ b/source/blender/editors/space_file/file_ops.c
@@ -146,9 +146,7 @@ static void file_select(SpaceFile* sfile, ARegion* ar, const rcti* rect, short v
 				strcat(params->dir,"/");
 				params->file[0] = '\0';
 				BLI_cleanup_dir(G.sce, params->dir);
-				filelist_setdir(sfile->files, params->dir);
-				filelist_free(sfile->files);
-				params->active_file = -1;
+				file_change_dir(sfile);
 			}
 		}
 		else if (file)
@@ -305,10 +303,8 @@ static int bookmark_select_invoke(bContext *C, wmOperator *op, wmEvent *event)
 		RNA_string_get(op->ptr, "dir", entry);
 		BLI_strncpy(params->dir, entry, sizeof(params->dir));
 		BLI_cleanup_dir(G.sce, params->dir);
-		filelist_free(sfile->files);	
-		filelist_setdir(sfile->files, params->dir);
-		params->file[0] = '\0';			
-		params->active_file = -1;
+		file_change_dir(sfile);				
+		params->file[0] = '\0';
 
 		WM_event_add_notifier(C, NC_FILE|ND_PARAMS, NULL);
 	}
@@ -467,7 +463,10 @@ void FILE_OT_highlight(struct wmOperatorType *ot)
 int file_cancel_exec(bContext *C, wmOperator *unused)
 {
 	SpaceFile *sfile= (SpaceFile*)CTX_wm_space_data(C);
-	
+
+	folderlist_free(sfile->folders_prev);
+	folderlist_free(sfile->folders_next);
+
 	WM_event_fileselect_event(C, sfile->op, EVT_FILESELECT_CANCEL);
 	sfile->op = NULL;
 	
@@ -529,6 +528,9 @@ int file_exec(bContext *C, wmOperator *unused)
 			}
 		}
 		
+		folderlist_free(sfile->folders_prev);
+		folderlist_free(sfile->folders_next);
+
 		fsmenu_insert_entry(fsmenu_get(), FS_CATEGORY_RECENT, sfile->params->dir,0, 1);
 		BLI_make_file_string(G.sce, name, BLI_gethome(), ".Bfs");
 		fsmenu_write_file(fsmenu_get(), name);
@@ -556,9 +558,7 @@ int file_parent_exec(bContext *C, wmOperator *unused)
 	
 	if(sfile->params) {
 		BLI_parent_dir(sfile->params->dir);
-		filelist_setdir(sfile->files, sfile->params->dir);
-		filelist_free(sfile->files);
-		sfile->params->active_file = -1;
+		file_change_dir(sfile);
 	}		
 	WM_event_add_notifier(C, NC_FILE|ND_FILELIST, NULL);
 
@@ -583,17 +583,74 @@ int file_refresh_exec(bContext *C, wmOperator *unused)
 {
 	SpaceFile *sfile= (SpaceFile*)CTX_wm_space_data(C);
 	
+	file_change_dir(sfile);
+
+	WM_event_add_notifier(C, NC_FILE|ND_FILELIST, NULL);
+
+	return OPERATOR_FINISHED;
+
+}
+
+void FILE_OT_previous(struct wmOperatorType *ot)
+{
+	/* identifiers */
+	ot->name= "Previous Folder";
+	ot->idname= "FILE_OT_previous";
+	
+	/* api callbacks */
+	ot->exec= file_previous_exec;
+	ot->poll= ED_operator_file_active; /* <- important, handler is on window level */
+}
+
+int file_previous_exec(bContext *C, wmOperator *unused)
+{
+	SpaceFile *sfile= (SpaceFile*)CTX_wm_space_data(C);
+
 	if(sfile->params) {
-		filelist_setdir(sfile->files, sfile->params->dir);
-		filelist_free(sfile->files);
-		sfile->params->active_file = -1;
+		if (!sfile->folders_next)
+			sfile->folders_next = folderlist_new();
+
+		folderlist_pushdir(sfile->folders_next, sfile->params->dir);
+		folderlist_popdir(sfile->folders_prev, sfile->params->dir);
+		folderlist_pushdir(sfile->folders_next, sfile->params->dir);
+
+		file_change_dir(sfile);
 	}
 	WM_event_add_notifier(C, NC_FILE|ND_FILELIST, NULL);
 
 	return OPERATOR_FINISHED;
+}
 
+void FILE_OT_next(struct wmOperatorType *ot)
+{
+	/* identifiers */
+	ot->name= "Next Folder";
+	ot->idname= "FILE_OT_next";
+	
+	/* api callbacks */
+	ot->exec= file_next_exec;
+	ot->poll= ED_operator_file_active; /* <- important, handler is on window level */
 }
 
+int file_next_exec(bContext *C, wmOperator *unused)
+{
+	SpaceFile *sfile= (SpaceFile*)CTX_wm_space_data(C);
+		if(sfile->params) {
+			if (!sfile->folders_next)
+			sfile->folders_next = folderlist_new();
+
+		folderlist_pushdir(sfile->folders_prev, sfile->params->dir);
+		folderlist_popdir(sfile->folders_next, sfile->params->dir);
+
+		// update folder_prev so we can check for it in folderlist_clear_next()
+		folderlist_pushdir(sfile->folders_prev, sfile->params->dir);
+
+		file_change_dir(sfile);
+	}		
+	WM_event_add_notifier(C, NC_FILE|ND_FILELIST, NULL);
+
+	return OPERATOR_FINISHED;
+}
 
 void FILE_OT_refresh(struct wmOperatorType *ot)
 {
diff --git a/source/blender/editors/space_file/filelist.c b/source/blender/editors/space_file/filelist.c
index 573aed72728..ab5dac1a727 100644
--- a/source/blender/editors/space_file/filelist.c
+++ b/source/blender/editors/space_file/filelist.c
@@ -123,6 +123,12 @@ typedef struct FileList
 	ListBase threads;
 } FileList;
 
+typedef struct FolderList
+{
+	struct FolderList *next, *prev;
+	char *foldername;
+} FolderList;
+
 #define SPECIAL_IMG_SIZE 48
 #define SPECIAL_IMG_ROWS 4
 #define SPECIAL_IMG_COLS 4
@@ -354,6 +360,86 @@ void filelist_free_icons()
 	}
 }
 
+//-----------------FOLDERLIST (previous/next) --------------//
+struct ListBase* folderlist_new()
+{
+	ListBase* p = MEM_callocN( sizeof(ListBase), "folderlist" );
+	return p;
+}
+
+void folderlist_popdir(struct ListBase* folderlist, const char *dir)
+{
+	const char *prev_dir;
+	struct FolderList *folder;
+	folder = folderlist->last;
+
+	if(folder){
+		// remove the current directory
+		MEM_freeN(folder->foldername);
+		BLI_freelinkN(folderlist, folder);
+
+		folder = folderlist->last;
+		if(folder){
+			prev_dir = folder->foldername;
+			BLI_strncpy(dir, prev_dir, FILE_MAXDIR);
+		}
+	}
+	// delete the folder next or use setdir directly before PREVIOUS OP
+}
+
+void folderlist_pushdir(ListBase* folderlist, const char *dir)
+{
+	struct FolderList *folder, *previous_folder;
+	previous_folder = folderlist->last;
+
+	// check if already exists
+	if(previous_folder){
+		if(! strcmp(previous_folder->foldername, dir)){
+			return;
+		}
+	}
+
+	// create next folder element
+	folder = (FolderList*)MEM_mallocN(sizeof(FolderList),"FolderList");
+	folder->foldername = (char*)MEM_mallocN(sizeof(char)*(strlen(dir)+1), "foldername");
+	folder->foldername[0] = '\0';
+
+	BLI_strncpy(folder->foldername, dir, FILE_MAXDIR);
+
+	// add it to the end of the list
+	BLI_addtail(folderlist, folder);
+}
+
+int folderlist_clear_next(struct SpaceFile *sfile)
+{
+	struct FolderList *folder;
+
+	// if there is no folder_next there is nothing we can clear
+	if (!sfile->folders_next)
+		return 0;
+
+	// if previous_folder, next_folder or refresh_folder operators are executed it doesn't clear folder_next
+	folder = sfile->folders_prev->last;
+	if ((!folder) ||(!strcmp(folder->foldername, sfile->params->dir)))
+		return 0;
+
+	// eventually clear flist->folders_next
+	return 1;
+}
+
+void folderlist_free(ListBase* folderlist)
+{
+	FolderList *folder;
+	if (folderlist){
+		for(folder= folderlist->last; folder; folder= folderlist->last) {
+				MEM_freeN(folder->foldername);
+				BLI_freelinkN(folderlist, folder);
+		}
+	}
+	folderlist= NULL;
+}
+
+//------------------FILELIST------------------------//
 struct FileList*	filelist_new()
 {
 	FileList* p = MEM_callocN( sizeof(FileList), "filelist" );
@@ -375,7 +461,7 @@ void filelist_free(struct FileList* filelist)
 	int i;
 
 	if (!filelist) {
-		printf("Attemtping to delete empty filelist.\n");
+		printf("Attempting to delete empty filelist.\n");
 		return;
 	}
 
diff --git a/source/blender/editors/space_file/filelist.h b/source/blender/editors/space_file/filelist.h
index e929e028849..0f8db98b7ab 100644
--- a/source/blender/editors/space_file/filelist.h
+++ b/source/blender/editors/space_file/filelist.h
@@ -38,6 +38,7 @@ extern "C" {
 #endif
 
 struct FileList;
+struct FolderList;
 struct direntry;
 struct BlendHandle;
 struct Scene;
@@ -70,6 +71,11 @@ int					filelist_empty(struct FileList* filelist);
 void				filelist_parent(struct FileList* filelist);
 void				filelist_setfiletypes(struct FileList* filelist, short has_quicktime);
 
+struct ListBase *	folderlist_new();
+void				folderlist_free(struct ListBase* folderlist);
+void				folderlist_popdir(struct ListBase* folderlist, const char *dir);
+void				folderlist_pushdir(struct ListBase* folderlist, const char *dir);
+int					folderlist_clear_next(struct SpaceFile* sfile);
 
 #ifdef __cplusplus
 }
diff --git a/source/blender/editors/space_file/filesel.c b/source/blender/editors/space_file/filesel.c
index ea42ad80fe6..c42c83eda98 100644
--- a/source/blender/editors/space_file/filesel.c
+++ b/source/blender/editors/space_file/filesel.c
@@ -84,12 +84,12 @@
 FileSelectParams* ED_fileselect_get_params(struct SpaceFile *sfile)
 {
 	if (!sfile->params) {
-		ED_fileselect_set_params(sfile, "", "/", 0, FILE_SHORTDISPLAY, 0, FILE_SORT_ALPHA);
+		ED_fileselect_set_params(sfile, "", NULL, "/", 0, FILE_SHORTDISPLAY, 0, FILE_SORT_ALPHA);
 	}
 	return sfile->params;
 }
 
-short ED_fileselect_set_params(SpaceFile *sfile, const char *title, const char *path,
+short ED_fileselect_set_params(SpaceFile *sfile, const char *title, const char *last_dir, const char *path,
 							   short flag, short display, short filter, short sort)
 {
 	char name[FILE_MAX], dir[FILE_MAX], file[FILE_MAX];
@@ -107,14 +107,19 @@ short ED_fileselect_set_params(SpaceFile *sfile, const char *title, const char *
 	params->sort = sort;
 
 	BLI_strncpy(params->title, title, sizeof(params->title));
-	
-	BLI_strncpy(name, path, sizeof(name));
-	BLI_convertstringcode(name, G.sce);
 
-	BLI_split_dirfile(name, dir, file);
-	BLI_strncpy(params->file, file, sizeof(params->file));
-	BLI_strncpy(params->dir, dir, sizeof(params->dir));
-	BLI_make_file_string(G.sce, params->dir, dir, ""); /* XXX needed ? - also solve G.sce */			
+	if(last_dir){
+		BLI_strncpy(params->dir, last_dir, sizeof(params->dir));
+	}
+	else {
+		BLI_strncpy(name, path, sizeof(name));
+		BLI_convertstringcode(name, G.sce);
+
+		BLI_split_dirfile(name, dir, file);
+		BLI_strncpy(params->file, file, sizeof(params->file));
+		BLI_strncpy(params->dir, dir, sizeof(params->dir));
+		BLI_make_file_string(G.sce, params->dir, dir, ""); /* XXX needed ? - also solve G.sce */			
+	}
 
 	return 1;
 }
@@ -279,3 +284,18 @@ FileLayout* ED_fileselect_get_layout(struct SpaceFile *sfile, struct ARegion *ar
 	}
 	return sfile->layout;
 }
+
+void file_change_dir(struct SpaceFile *sfile)
+{
+	if (sfile->params) {
+		filelist_setdir(sfile->files, sfile->params->dir);
+
+		if(folderlist_clear_next(sfile))
+			folderlist_free(sfile->folders_next);
+
+		folderlist_pushdir(sfile->folders_prev, sfile->params->dir);
+
+		filelist_free(sfile->files);
+		sfile->params->active_file = -1;
+	}
+}
diff --git a/source/blender/editors/space_file/space_file.c b/source/blender/editors/space_file/space_file.c
index 9c30a0ed988..3167d2809c9 100644
--- a/source/blender/editors/space_file/space_file.c
+++ b/source/blender/editors/space_file/space_file.c
@@ -124,6 +124,18 @@ static void file_free(SpaceLink *sl)
 		sfile->files= NULL;
 	}
 
+	if(sfile->folders_prev) {
+		folderlist_free(sfile->folders_prev);
+		MEM_freeN(sfile->folders_prev);
+		sfile->folders_prev= NULL;
+	}
+
+	if(sfile->folders_next) {
+		folderlist_free(sfile->folders_next);
+		MEM_freeN(sfile->folders_next);
+		sfile->folders_next= NULL;
+	}
+
 	if (sfile->params) {
 		if(sfile->params->pupmenu)
 			MEM_freeN(sfile->params->pupmenu);
@@ -153,11 +165,15 @@ static SpaceLink *file_duplicate(SpaceLink *sl)
 	sfilen->op = NULL; /* file window doesn't own operators */
 
 	sfilen->files = filelist_new();
-	
+	if(sfileo->folders_prev)
+		sfilen->folders_prev = MEM_dupallocN(sfileo->folders_prev);
+
+	if(sfileo->folders_next)
+		sfilen->folders_next = MEM_dupallocN(sfileo->folders_next);
+
 	if(sfileo->params) {
 		sfilen->params= MEM_dupallocN(sfileo->params);
-	
-		filelist_setdir(sfilen->files, sfilen->params->dir);
+		file_change_dir(sfilen);
 	}
 	if (sfileo->layout) {
 		sfilen->layout= MEM_dupallocN(sfileo->layout);
@@ -170,9 +186,11 @@ static void file_refresh(const bContext *C, ScrArea *sa)
 	SpaceFile *sfile= (SpaceFile*)CTX_wm_space_data(C);
 	FileSelectParams *params = ED_fileselect_get_params(sfile);
 
+	if (!sfile->folders_prev)
+		sfile->folders_prev = folderlist_new();
 	if (!sfile->files) {
 		sfile->files = filelist_new();
-		filelist_setdir(sfile->files, params->dir);
+		file_change_dir(sfile);
 		params->active_file = -1; // added this so it opens nicer (ton)
 	}
 	filelist_hidedot(sfile->files, params->flag & FILE_HIDE_DOT);
@@ -295,6 +313,8 @@ void file_operatortypes(void)
 	WM_operatortype_append(FILE_OT_exec);
 	WM_operatortype_append(FILE_OT_cancel);
 	WM_operatortype_append(FILE_OT_parent);
+	WM_operatortype_append(FILE_OT_previous);
+	WM_operatortype_append(FILE_OT_next);
 	WM_operatortype_append(FILE_OT_refresh);
 	WM_operatortype_append(FILE_OT_bookmark_toggle);
 	WM_operatortype_append(FILE_OT_add_bookmark);
@@ -313,6 +333,8 @@ void file_keymap(struct wmWindowManager *wm)
 	WM_keymap_add_item(keymap, "FILE_OT_parent", PKEY, KM_PRESS, 0, 0);
 	WM_keymap_add_item(keymap, "FILE_OT_add_bookmark", BKEY, KM_PRESS, KM_CTRL, 0);
 	WM_keymap_add_item(keymap, "FILE_OT_hidedot", HKEY, KM_PRESS, 0, 0);
+	WM_keymap_add_item(keymap, "FILE_OT_previous", BACKSPACEKEY, KM_PRESS, 0, 0);
+	WM_keymap_add_item(keymap, "FILE_OT_next", BACKSPACEKEY, KM_PRESS, KM_SHIFT, 0);
 
 	/* keys for main area */
 	keymap= WM_keymap_listbase(wm, "FileMain", SPACE_FILE, 0);