netsurf/desktop/global_history.c

/*
 * Copyright 2012 - 2013 Michael Drake <tlsa@netsurf-browser.org>
 *
 * This file is part of NetSurf, http://www.netsurf-browser.org/
 *
 * NetSurf 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; version 2 of the License.
 *
 * NetSurf 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */


#include <stdlib.h>
#include <string.h>
#include <time.h>

#include "utils/messages.h"
#include "utils/utils.h"
#include "utils/utf8.h"
#include "utils/libdom.h"
#include "utils/log.h"
#include "utils/nsurl.h"
#include "content/urldb.h"

#include "desktop/global_history.h"
#include "desktop/treeview.h"
#include "netsurf/browser_window.h"

#define N_DAYS 28
#define N_SEC_PER_DAY (60 * 60 * 24)

enum global_history_folders {
	GH_TODAY = 0,
	GH_YESTERDAY,
	GH_2_DAYS_AGO,
	GH_3_DAYS_AGO,
	GH_4_DAYS_AGO,
	GH_5_DAYS_AGO,
	GH_6_DAYS_AGO,
	GH_LAST_WEEK,
	GH_2_WEEKS_AGO,
	GH_3_WEEKS_AGO,
	GH_N_FOLDERS
};

enum global_history_fields {
	GH_TITLE,
	GH_URL,
	GH_LAST_VISIT,
	GH_VISITS,
	GH_PERIOD,
	N_FIELDS
};

struct global_history_folder {
	treeview_node *folder;
	struct treeview_field_data data;
};

struct global_history_ctx {
	treeview *tree;
	struct treeview_field_desc fields[N_FIELDS];
	struct global_history_folder folders[GH_N_FOLDERS];
	time_t today;
	int weekday;
	bool built;
};
struct global_history_ctx gh_ctx;

struct global_history_entry {
	bool user_delete;

	int slot;
	nsurl *url;
	time_t t;
	treeview_node *entry;
	struct global_history_entry *next;
	struct global_history_entry *prev;

	struct treeview_field_data data[N_FIELDS - 1];
};
struct global_history_entry *gh_list[N_DAYS];


/**
 * Find an entry in the global history
 *
 * \param url The URL to find
 * \return Pointer to history entry, or NULL if not found
 */
static struct global_history_entry *global_history_find(nsurl *url)
{
	int i;
	struct global_history_entry *e;

	for (i = 0; i < N_DAYS; i++) {
		e = gh_list[i];

		while (e != NULL) {
			if (nsurl_compare(e->url, url,
					NSURL_COMPLETE) == true) {
				/* Got a match */
				return e;
			}
			e = e->next;
		}

	}

	/* No match found */
	return NULL;
}


/**
 * Initialise the treeview directories
 *
 * \param f		Ident for folder to create
 * \return NSERROR_OK on success, appropriate error otherwise
 */
static nserror global_history_create_dir(enum global_history_folders f)
{
	nserror err;
	treeview_node *relation = NULL;
	enum treeview_relationship rel = TREE_REL_FIRST_CHILD;
	const char *label;
	int i;

	switch (f) {
	case GH_TODAY:
		label = "DateToday";
		break;

	case GH_YESTERDAY:
		label = "DateYesterday";
		break;

	case GH_2_DAYS_AGO:
		label = "Date2Days";
		break;

	case GH_3_DAYS_AGO:
		label = "Date3Days";
		break;

	case GH_4_DAYS_AGO:
		label = "Date4Days";
		break;

	case GH_5_DAYS_AGO:
		label = "Date5Days";
		break;

	case GH_6_DAYS_AGO:
		label = "Date6Days";
		break;

	case GH_LAST_WEEK:
		label = "Date1Week";
		break;

	case GH_2_WEEKS_AGO:
		label = "Date2Week";
		break;

	case GH_3_WEEKS_AGO:
		label = "Date3Week";
		break;

	default:
		return NSERROR_BAD_PARAMETER;
	}

	label = messages_get(label);

	for (i = f - 1; i >= 0; i--) {
		if (gh_ctx.folders[i].folder != NULL) {
			relation = gh_ctx.folders[i].folder;
			rel = TREE_REL_NEXT_SIBLING;
			break;
		}
	}

	gh_ctx.folders[f].data.field = gh_ctx.fields[N_FIELDS - 1].field;
	gh_ctx.folders[f].data.value = label;
	gh_ctx.folders[f].data.value_len = strlen(label);
	err = treeview_create_node_folder(gh_ctx.tree,
			&gh_ctx.folders[f].folder,
			relation, rel,
			&gh_ctx.folders[f].data,
			&gh_ctx.folders[f],
			gh_ctx.built ? TREE_OPTION_NONE :
					TREE_OPTION_SUPPRESS_RESIZE |
					TREE_OPTION_SUPPRESS_REDRAW);

	return err;
}


/**
 * Get the treeview folder for history entires in a particular slot
 *
 * \param parent	Updated to parent folder.
 * \param slot		Global history slot of entry we want folder node for
 * \return NSERROR_OK on success, appropriate error otherwise
 */
static inline nserror global_history_get_parent_treeview_node(
		treeview_node **parent, int slot)
{
	int folder_index;
	struct global_history_folder *f;
	nserror err;

	if (slot < 7) {
		folder_index = slot;

	} else if (slot < 14) {
		folder_index = GH_LAST_WEEK;

	} else if (slot < 21) {
		folder_index = GH_2_WEEKS_AGO;

	} else if (slot < N_DAYS) {
		folder_index = GH_3_WEEKS_AGO;

	} else {
		/* Slot value is invalid */
		return NSERROR_BAD_PARAMETER;
	}

	/* Get the folder */
	f = &(gh_ctx.folders[folder_index]);

	if (f->folder == NULL) {
		err = global_history_create_dir(folder_index);
		if (err != NSERROR_OK) {
			*parent = NULL;
			return err;
		}
	}

	/* Return the parent treeview folder */
	*parent = f->folder;
	return NSERROR_OK;
}


/**
 * Set a global history entry's data from the url_data.
 *
 * \param e		Global history entry to set up
 * \param data	Data associated with entry's URL
 * \return NSERROR_OK on success, appropriate error otherwise
 */
static nserror global_history_create_treeview_field_data(
		struct global_history_entry *e,
		const struct url_data *data)
{
	const char *title = (data->title != NULL) ?
			data->title : messages_get("NoTitle");
	char buffer[16];
	struct tm *lvtime;
	char *last_visited = NULL;
	size_t len = 0;

	e->data[GH_TITLE].field = gh_ctx.fields[GH_TITLE].field;
	e->data[GH_TITLE].value = strdup(title);
	e->data[GH_TITLE].value_len = (e->data[GH_TITLE].value != NULL) ?
			strlen(title) : 0;

	e->data[GH_URL].field = gh_ctx.fields[GH_URL].field;
	e->data[GH_URL].value = nsurl_access(e->url);
	e->data[GH_URL].value_len = nsurl_length(e->url);

	if ((lvtime = localtime(&data->last_visit)) != NULL) {
		const size_t lvsize = 256;
		last_visited = malloc(lvsize);
		if (last_visited != NULL) {
			len = strftime(last_visited, lvsize,
					"%a %b %e %H:%M:%S %Y", lvtime);
		}
	}

	e->data[GH_LAST_VISIT].field = gh_ctx.fields[GH_LAST_VISIT].field;
	e->data[GH_LAST_VISIT].value = last_visited;
	e->data[GH_LAST_VISIT].value_len = len;

	len = snprintf(buffer, 16, "%u", data->visits);
	if (len == 16) {
		len--;
		buffer[len] = '\0';
	}

	e->data[GH_VISITS].field = gh_ctx.fields[GH_VISITS].field;
	e->data[GH_VISITS].value = strdup(buffer);
	e->data[GH_VISITS].value_len = len;

	return NSERROR_OK;
}

/**
 * Add a global history entry to the treeview
 *
 * \param e	entry to add to treeview
 * \param slot  global history slot containing entry
 * \return NSERROR_OK on success, or appropriate error otherwise
 *
 * It is assumed that the entry is unique (for its URL) in the global
 * history table
 */
static nserror global_history_entry_insert(struct global_history_entry *e,
		int slot)
{
	nserror err;

	treeview_node *parent;
	err = global_history_get_parent_treeview_node(&parent, slot);
	if (err != NSERROR_OK) {
		return err;
	}

	err = treeview_create_node_entry(gh_ctx.tree, &(e->entry),
			parent, TREE_REL_FIRST_CHILD, e->data, e,
			gh_ctx.built ? TREE_OPTION_NONE :
					TREE_OPTION_SUPPRESS_RESIZE |
					TREE_OPTION_SUPPRESS_REDRAW);
	if (err != NSERROR_OK) {
		return err;
	}

	return NSERROR_OK;
}


/**
 * Add an entry to the global history (creates the entry).
 *
 * If the treeview has already been created, the entry will be added to the
 * treeview.  Otherwise, the entry will have to be added to the treeview later.
 *
 * When we first create the global history we create it without the treeview, to
 * simplfy sorting the entries.
 *
 * \param url		URL for entry to add to history
 * \param slot		Global history slot to contain history entry
 * \param data		URL data for the entry
 * \param got_treeview	Whether the treeview has been created already
 * \return NSERROR_OK on success, or appropriate error otherwise
 */
static nserror global_history_add_entry_internal(nsurl *url, int slot,
		const struct url_data *data, bool got_treeview)
{
	nserror err;
	struct global_history_entry *e;

	/* Create new local history entry */
	e = malloc(sizeof(struct global_history_entry));
	if (e == NULL) {
		return NSERROR_NOMEM;
	}

	e->user_delete = false;
	e->slot = slot;
	e->url = nsurl_ref(url);
	e->t = data->last_visit;
	e->entry = NULL;
	e->next = NULL;
	e->prev = NULL;

	err = global_history_create_treeview_field_data(e, data);
	if (err != NSERROR_OK) {
		return err;
	}
	
	if (gh_list[slot] == NULL) {
		/* list empty */
		gh_list[slot] = e;

	} else if (gh_list[slot]->t < e->t) {
		/* Insert at list head */
		e->next = gh_list[slot];
		gh_list[slot]->prev = e;
		gh_list[slot] = e;
	} else {
		struct global_history_entry *prev = gh_list[slot];
		struct global_history_entry *curr = prev->next;
		while (curr != NULL) {
			if (curr->t < e->t) {
				break;
			}
			prev = curr;
			curr = curr->next;
		}

		/* insert after prev */
		e->next = curr;
		e->prev = prev;
		prev->next = e;

		if (curr != NULL)
			curr->prev = e;
	}

	if (got_treeview) {
		err = global_history_entry_insert(e, slot);
		if (err != NSERROR_OK) {
			return err;
		}
	}

	return NSERROR_OK;
}


/**
 * Delete a global history entry
 *
 * This does not delete the treeview node, rather it should only be called from
 * the treeview node delete event message.
 *
 * \param e		Entry to delete
 */
static void global_history_delete_entry_internal(
		struct global_history_entry *e)
{
	assert(e != NULL);
	assert(e->entry == NULL);

	/* Unlink */
	if (gh_list[e->slot] == e) {
		/* e is first entry */
		gh_list[e->slot] = e->next;

		if (e->next != NULL)
			e->next->prev = NULL;

	} else if (e->next == NULL) {
		/* e is last entry */
		e->prev->next = NULL;

	} else {
		/* e has an entry before and after */
		e->prev->next = e->next;
		e->next->prev = e->prev;
	}

	if (e->user_delete) {
		/* User requested delete, so delete from urldb too. */
		urldb_reset_url_visit_data(e->url);
	}

	/* Destroy fields */
	free((void *)e->data[GH_TITLE].value); /* Eww */
	free((void *)e->data[GH_LAST_VISIT].value); /* Eww */
	free((void *)e->data[GH_VISITS].value); /* Eww */
	nsurl_unref(e->url);

	/* Destroy entry */
	free(e);
}

/**
 * Internal routine to actually perform global history addition
 *
 * \param url The URL to add
 * \param data URL data associated with URL
 * \return true (for urldb_iterate_entries)
 */
static bool global_history_add_entry(nsurl *url,
		const struct url_data *data)
{
	int slot;
	time_t visit_date;
	time_t earliest_date = gh_ctx.today - (N_DAYS - 1) * N_SEC_PER_DAY;
	bool got_treeview = gh_ctx.tree != NULL;

	assert((url != NULL) && (data != NULL));

	visit_date = data->last_visit;

	/* Find day array slot for entry */
	if (visit_date >= gh_ctx.today) {
		slot = 0;
	} else if (visit_date >= earliest_date) {
		slot = (gh_ctx.today - visit_date) / N_SEC_PER_DAY + 1;
	} else {
		/* too old */
		return true;
	}

	if (got_treeview == true) {
		/* The treeview for global history already exists */
		struct global_history_entry *e;

		/* Delete any existing entry for this URL */
		e = global_history_find(url);
		if (e != NULL) {
			treeview_delete_node(gh_ctx.tree, e->entry,
					TREE_OPTION_SUPPRESS_REDRAW |
					TREE_OPTION_SUPPRESS_RESIZE);
		}
	}

	if (global_history_add_entry_internal(url, slot, data,
			got_treeview) != NSERROR_OK) {
		return false;
	}

	return true;
}

/**
 * Initialise the treeview entry feilds
 *
 * \return NSERROR_OK on success, or appropriate error otherwise
 */
static nserror global_history_initialise_entry_fields(void)
{
	int i;
	const char *label;

	for (i = 0; i < N_FIELDS; i++)
		gh_ctx.fields[i].field = NULL;

	gh_ctx.fields[GH_TITLE].flags = TREE_FLAG_DEFAULT;
	label = "TreeviewLabelTitle";
	label = messages_get(label);
	if (lwc_intern_string(label, strlen(label),
			&gh_ctx.fields[GH_TITLE].field) !=
			lwc_error_ok) {
		goto error;
	}

	gh_ctx.fields[GH_URL].flags =
			TREE_FLAG_COPY_TEXT |
			TREE_FLAG_SEARCHABLE;
	label = "TreeviewLabelURL";
	label = messages_get(label);
	if (lwc_intern_string(label, strlen(label),
			&gh_ctx.fields[GH_URL].field) !=
			lwc_error_ok) {
		goto error;
	}

	gh_ctx.fields[GH_LAST_VISIT].flags = TREE_FLAG_SHOW_NAME;
	label = "TreeviewLabelLastVisit";
	label = messages_get(label);
	if (lwc_intern_string(label, strlen(label),
			&gh_ctx.fields[GH_LAST_VISIT].field) !=
			lwc_error_ok) {
		goto error;
	}

	gh_ctx.fields[GH_VISITS].flags = TREE_FLAG_SHOW_NAME;
	label = "TreeviewLabelVisits";
	label = messages_get(label);
	if (lwc_intern_string(label, strlen(label),
			&gh_ctx.fields[GH_VISITS].field) !=
			lwc_error_ok) {
		goto error;
	}

	gh_ctx.fields[GH_PERIOD].flags = TREE_FLAG_DEFAULT;
	label = "TreeviewLabelPeriod";
	label = messages_get(label);
	if (lwc_intern_string(label, strlen(label),
			&gh_ctx.fields[GH_PERIOD].field) !=
			lwc_error_ok) {
		return false;
	}

	return NSERROR_OK;

error:
	for (i = 0; i < N_FIELDS; i++)
		if (gh_ctx.fields[i].field != NULL)
			lwc_string_unref(gh_ctx.fields[i].field);

	return NSERROR_UNKNOWN;
}


/**
 * Initialise the time
 *
 * \return NSERROR_OK on success, or appropriate error otherwise
 */
static nserror global_history_initialise_time(void)
{
	struct tm *full_time;
	time_t t;

	/* get the current time */
	t = time(NULL);
	if (t == -1) {
		NSLOG(netsurf, INFO, "time info unaviable");
		return NSERROR_UNKNOWN;
	}

	/* get the time at the start of today */
	full_time = localtime(&t);
	full_time->tm_sec = 0;
	full_time->tm_min = 0;
	full_time->tm_hour = 0;
	t = mktime(full_time);
	if (t == -1) {
		NSLOG(netsurf, INFO, "mktime failed");
		return NSERROR_UNKNOWN;
	}

	gh_ctx.today = t;
	gh_ctx.weekday = full_time->tm_wday;

	return NSERROR_OK;
}


/**
 * Initialise the treeview entries
 *
 * \return NSERROR_OK on success, or appropriate error otherwise
 */
static nserror global_history_init_entries(void)
{
	int i;
	nserror err;

	/* Itterate over all global history data, inserting it into treeview */
	for (i = 0; i < N_DAYS; i++) {
		struct global_history_entry *l = NULL;
		struct global_history_entry *e = gh_list[i];

		/* Insert in reverse order; find last */
		while (e != NULL) {
			l = e;
			e = e->next;
		}

		/* Insert the entries into the treeview */
		while (l != NULL) {
			err = global_history_entry_insert(l, i);
			if (err != NSERROR_OK) {
				return err;
			}
			l = l->prev;
		}
	}

	return NSERROR_OK;
}


static nserror global_history_tree_node_folder_cb(
		struct treeview_node_msg msg, void *data)
{
	struct global_history_folder *f = data;

	switch (msg.msg) {
	case TREE_MSG_NODE_DELETE:
		f->folder = NULL;
		break;

	case TREE_MSG_NODE_EDIT:
		break;

	case TREE_MSG_NODE_LAUNCH:
		break;
	}

	return NSERROR_OK;
}

static nserror
global_history_tree_node_entry_cb(struct treeview_node_msg msg, void *data)
{
	struct global_history_entry *e = data;
	nserror ret = NSERROR_OK;

	switch (msg.msg) {
	case TREE_MSG_NODE_DELETE:
		e->entry = NULL;
		e->user_delete = msg.data.delete.user;
		global_history_delete_entry_internal(e);
		break;

	case TREE_MSG_NODE_EDIT:
		break;

	case TREE_MSG_NODE_LAUNCH:
	{
		struct browser_window *existing = NULL;
		enum browser_window_create_flags flags = BW_CREATE_HISTORY;

		/* TODO: Set existing to window that new tab appears in */

		if (msg.data.node_launch.mouse &
				(BROWSER_MOUSE_MOD_1 | BROWSER_MOUSE_MOD_2) ||
				existing == NULL) {
			/* Shift or Ctrl launch, open in new window rather
			 * than tab. */
			/* TODO: flags ^= BW_CREATE_TAB; */
		}

		ret = browser_window_create(flags, e->url, NULL,
				existing, NULL);
	}
		break;
	}
	return ret;
}

struct treeview_callback_table gh_tree_cb_t = {
	.folder = global_history_tree_node_folder_cb,
	.entry = global_history_tree_node_entry_cb
};


/* Exported interface, documented in global_history.h */
nserror global_history_init(void *core_window_handle)
{
	nserror err;

	err = treeview_init();
	if (err != NSERROR_OK) {
		return err;
	}

	NSLOG(netsurf, INFO, "Loading global history");

	/* Init. global history treeview time */
	err = global_history_initialise_time();
	if (err != NSERROR_OK) {
		gh_ctx.tree = NULL;
		return err;
	}

	/* Init. global history treeview entry fields */
	err = global_history_initialise_entry_fields();
	if (err != NSERROR_OK) {
		gh_ctx.tree = NULL;
		return err;
	}

	/* Load the entries */
	urldb_iterate_entries(global_history_add_entry);

	/* Create the global history treeview */
	err = treeview_create(&gh_ctx.tree, &gh_tree_cb_t,
			N_FIELDS, gh_ctx.fields,
			core_window_handle,
			TREEVIEW_NO_MOVES | TREEVIEW_DEL_EMPTY_DIRS |
			TREEVIEW_SEARCHABLE);
	if (err != NSERROR_OK) {
		gh_ctx.tree = NULL;
		return err;
	}

	/* Ensure there is a folder for today */
	err = global_history_create_dir(GH_TODAY);
	if (err != NSERROR_OK) {
		return err;
	}

	/* Add the history to the treeview */
	err = global_history_init_entries();
	if (err != NSERROR_OK) {
		return err;
	}

	/* Expand the "Today" folder node */
	err = treeview_node_expand(gh_ctx.tree,
			gh_ctx.folders[GH_TODAY].folder);
	if (err != NSERROR_OK) {
		return err;
	}

	/* History tree is built
	 * We suppress the treeview height callback on entry insertion before
	 * the treeview is built. */
	gh_ctx.built = true;

	/* Inform client of window height */
	treeview_get_height(gh_ctx.tree);

	NSLOG(netsurf, INFO, "Loaded global history");

	return NSERROR_OK;
}


/* Exported interface, documented in global_history.h */
nserror global_history_fini(void)
{
	int i;
	nserror err;

	NSLOG(netsurf, INFO, "Finalising global history");

	gh_ctx.built = false;

	/* Destroy the global history treeview */
	err = treeview_destroy(gh_ctx.tree);
	gh_ctx.tree = NULL;

	/* Free global history treeview entry fields */
	for (i = 0; i < N_FIELDS; i++)
		if (gh_ctx.fields[i].field != NULL)
			lwc_string_unref(gh_ctx.fields[i].field);

	err = treeview_fini();
	if (err != NSERROR_OK) {
		return err;
	}

	NSLOG(netsurf, INFO, "Finalised global history");

	return err;
}


/* Exported interface, documented in global_history.h */
nserror global_history_add(nsurl *url)
{
	const struct url_data *data;

	/* If we don't have a global history at the moment, just return OK */
	if (gh_ctx.tree == NULL)
		return NSERROR_OK;

	data = urldb_get_url_data(url);
	if (data == NULL) {
		NSLOG(netsurf, INFO,
		      "Can't add URL to history that's not present in urldb.");
		return NSERROR_BAD_PARAMETER;
	}

	global_history_add_entry(url, data);

	return NSERROR_OK;
}


struct treeview_export_walk_ctx {
	FILE *fp;
};
/** Callback for treeview_walk node entering */
static nserror global_history_export_enter_cb(void *ctx, void *node_data,
		enum treeview_node_type type, bool *abort)
{
	struct treeview_export_walk_ctx *tw = ctx;
	nserror ret;

	if (type == TREE_NODE_ENTRY) {
		struct global_history_entry *e = node_data;
		char *t_text;
		char *u_text;

		ret = utf8_to_html(e->data[GH_TITLE].value, "iso-8859-1",
				e->data[GH_TITLE].value_len, &t_text);
		if (ret != NSERROR_OK)
			return NSERROR_SAVE_FAILED;

		ret = utf8_to_html(e->data[GH_URL].value, "iso-8859-1",
				e->data[GH_URL].value_len, &u_text);
		if (ret != NSERROR_OK) {
			free(t_text);
			return NSERROR_SAVE_FAILED;
		}

		fprintf(tw->fp, "<li><a href=\"%s\">%s</a></li>\n",
			u_text, t_text);

		free(t_text);
		free(u_text);

	} else if (type == TREE_NODE_FOLDER) {
		struct global_history_folder *f = node_data;
		char *f_text;

		ret = utf8_to_html(f->data.value, "iso-8859-1",
				f->data.value_len, &f_text);
		if (ret != NSERROR_OK)
			return NSERROR_SAVE_FAILED;

		fprintf(tw->fp, "<li><h4>%s</h4>\n<ul>\n", f_text);

		free(f_text);
	}

	return NSERROR_OK;
}
/** Callback for treeview_walk node leaving */
static nserror global_history_export_leave_cb(void *ctx, void *node_data,
		enum treeview_node_type type, bool *abort)
{
	struct treeview_export_walk_ctx *tw = ctx;

	if (type == TREE_NODE_FOLDER) {
		fputs("</ul></li>\n", tw->fp);
	}

	return NSERROR_OK;
}
/* Exported interface, documented in global_history.h */
nserror global_history_export(const char *path, const char *title)
{
	struct treeview_export_walk_ctx tw;
	nserror err;
	FILE *fp;

	fp = fopen(path, "w");
	if (fp == NULL)
		return NSERROR_SAVE_FAILED;

	if (title == NULL)
		title = "NetSurf Browsing History";

	fputs("<!DOCTYPE html "
		"PUBLIC \"//W3C/DTD HTML 4.01//EN\" "
		"\"http://www.w3.org/TR/html4/strict.dtd\">\n", fp);
	fputs("<html>\n<head>\n", fp);
	fputs("<meta http-equiv=\"Content-Type\" "
		"content=\"text/html; charset=iso-8859-1\">\n", fp);
	fprintf(fp, "<title>%s</title>\n", title);
	fputs("</head>\n<body>\n<ul>\n", fp);

	tw.fp = fp;
	err = treeview_walk(gh_ctx.tree, NULL,
			global_history_export_enter_cb,
			global_history_export_leave_cb,
			&tw, TREE_NODE_ENTRY | TREE_NODE_FOLDER);
	if (err != NSERROR_OK)
		return err;

	fputs("</ul>\n</body>\n</html>\n", fp);

	fclose(fp);

	return NSERROR_OK;
}


/* Exported interface, documented in global_history.h */
void global_history_redraw(int x, int y, struct rect *clip,
		const struct redraw_context *ctx)
{
	treeview_redraw(gh_ctx.tree, x, y, clip, ctx);
}


/* Exported interface, documented in global_history.h */
void global_history_mouse_action(browser_mouse_state mouse, int x, int y)
{
	treeview_mouse_action(gh_ctx.tree, mouse, x, y);
}


/* Exported interface, documented in global_history.h */
bool global_history_keypress(uint32_t key)
{
	return treeview_keypress(gh_ctx.tree, key);
}


/* Exported interface, documented in global_history.h */
bool global_history_has_selection(void)
{
	return treeview_has_selection(gh_ctx.tree);
}


/* Exported interface, documented in global_history.h */
bool global_history_get_selection(nsurl **url, const char **title)
{
	struct global_history_entry *e;
	enum treeview_node_type type;
	void *v;

	type = treeview_get_selection(gh_ctx.tree, &v);
	if (type != TREE_NODE_ENTRY || v == NULL) {
		*url = NULL;
		*title = NULL;
		return false;
	}

	e = (struct global_history_entry *)v;

	*url = e->url;
	*title = e->data[GH_TITLE].value;
	return true;
}


/* Exported interface, documented in global_history.h */
nserror global_history_expand(bool only_folders)
{
	return treeview_expand(gh_ctx.tree, only_folders);
}


/* Exported interface, documented in global_history.h */
nserror global_history_contract(bool all)
{
	return treeview_contract(gh_ctx.tree, all);
}