global_history.c

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/*
 * 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(struct core_window_callback_table *cw_t,
                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,
                        cw_t, 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);
}