source: mainline/uspace/lib/ui/src/filelist.c@ 11662bd

/*
 * Copyright (c) 2022 Jiri Svoboda
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup libui
 * @{
 */
/** @file File list.
 *
 * Displays a file listing.
 */

#include <dirent.h>
#include <errno.h>
#include <gfx/render.h>
#include <gfx/text.h>
#include <stdlib.h>
#include <str.h>
#include <ui/control.h>
#include <ui/filelist.h>
#include <ui/paint.h>
#include <ui/resource.h>
#include <vfs/vfs.h>
#include <qsort.h>
#include "../private/filelist.h"
#include "../private/resource.h"

static void ui_file_list_ctl_destroy(void *);
static errno_t ui_file_list_ctl_paint(void *);
static ui_evclaim_t ui_file_list_ctl_kbd_event(void *, kbd_event_t *);
static ui_evclaim_t ui_file_list_ctl_pos_event(void *, pos_event_t *);

/** File list control ops */
ui_control_ops_t ui_file_list_ctl_ops = {
        .destroy = ui_file_list_ctl_destroy,
        .paint = ui_file_list_ctl_paint,
        .kbd_event = ui_file_list_ctl_kbd_event,
        .pos_event = ui_file_list_ctl_pos_event
};

enum {
        file_list_entry_hpad = 2,
        file_list_entry_vpad = 2,
        file_list_entry_hpad_text = 1,
        file_list_entry_vpad_text = 0,
};

/** Create file list.
 *
 * @param window Containing window
 * @param active @c true iff file list should be active
 * @param rflist Place to store pointer to new file list
 * @return EOK on success or an error code
 */
errno_t ui_file_list_create(ui_window_t *window, bool active,
    ui_file_list_t **rflist)
{
        ui_file_list_t *flist;
        errno_t rc;

        flist = calloc(1, sizeof(ui_file_list_t));
        if (flist == NULL)
                return ENOMEM;

        rc = ui_control_new(&ui_file_list_ctl_ops, (void *)flist,
            &flist->control);
        if (rc != EOK) {
                free(flist);
                return rc;
        }

        rc = gfx_color_new_ega(0x0f, &flist->dir_color);
        if (rc != EOK)
                goto error;

        rc = gfx_color_new_ega(0x0a, &flist->svc_color);
        if (rc != EOK)
                goto error;

        flist->window = window;
        list_initialize(&flist->entries);
        flist->entries_cnt = 0;
        flist->active = active;

        *rflist = flist;
        return EOK;
error:
        if (flist->dir_color != NULL)
                gfx_color_delete(flist->dir_color);
        if (flist->svc_color != NULL)
                gfx_color_delete(flist->svc_color);
        ui_control_delete(flist->control);
        free(flist);
        return rc;
}

/** Destroy file list.
 *
 * @param flist File list
 */
void ui_file_list_destroy(ui_file_list_t *flist)
{
        ui_file_list_clear_entries(flist);
        ui_control_delete(flist->control);
        free(flist);
}

/** Set file list callbacks.
 *
 * @param flist File list
 * @param cb Callbacks
 * @param arg Argument to callback functions
 */
void ui_file_list_set_cb(ui_file_list_t *flist, ui_file_list_cb_t *cb, void *arg)
{
        flist->cb = cb;
        flist->cb_arg = arg;
}

/** Get height of file list entry.
 *
 * @param flist File list
 * @return Entry height in pixels
 */
gfx_coord_t ui_file_list_entry_height(ui_file_list_t *flist)
{
        ui_resource_t *res;
        gfx_font_metrics_t metrics;
        gfx_coord_t height;
        gfx_coord_t vpad;

        res = ui_window_get_res(flist->window);

        if (res->textmode) {
                vpad = file_list_entry_vpad_text;
        } else {
                vpad = file_list_entry_vpad;
        }

        /* Normal menu entry */
        gfx_font_get_metrics(res->font, &metrics);
        height = metrics.ascent + metrics.descent + 1;

        return height + 2 * vpad;
}

/** Paint file list entry.
 *
 * @param entry File list entry
 * @param entry_idx Entry index (within list of entries)
 * @return EOK on success or an error code
 */
errno_t ui_file_list_entry_paint(ui_file_list_entry_t *entry, size_t entry_idx)
{
        ui_file_list_t *flist = entry->flist;
        gfx_context_t *gc = ui_window_get_gc(flist->window);
        ui_resource_t *res = ui_window_get_res(flist->window);
        gfx_font_t *font = ui_resource_get_font(res);
        gfx_text_fmt_t fmt;
        gfx_coord2_t pos;
        gfx_rect_t rect;
        gfx_rect_t lrect;
        gfx_color_t *bgcolor;
        char *caption;
        gfx_coord_t hpad, vpad;
        gfx_coord_t line_height;
        size_t rows;
        errno_t rc;
        int rv;

        line_height = ui_file_list_entry_height(flist);
        ui_file_list_inside_rect(entry->flist, &lrect);

        gfx_text_fmt_init(&fmt);
        fmt.font = font;
        rows = ui_file_list_page_size(flist);

        /* Do not display entry outside of current page */
        if (entry_idx < flist->page_idx ||
            entry_idx >= flist->page_idx + rows)
                return EOK;

        if (res->textmode) {
                hpad = file_list_entry_hpad_text;
                vpad = file_list_entry_vpad_text;
        } else {
                hpad = file_list_entry_hpad;
                vpad = file_list_entry_vpad;
        }

        pos.x = lrect.p0.x;
        pos.y = lrect.p0.y + line_height * (entry_idx - flist->page_idx);

        if (entry == flist->cursor && flist->active) {
                fmt.color = res->entry_sel_text_fg_color;
                bgcolor = res->entry_sel_text_bg_color;
        } else if (entry->isdir) {
                if (res->textmode) {
                        fmt.color = flist->dir_color;
                        bgcolor = flist->dir_color;
                } else {
                        fmt.color = res->entry_fg_color;
                        bgcolor = res->entry_bg_color;
                }
        } else if (entry->svc != 0) {
                if (res->textmode) {
                        fmt.color = flist->svc_color;
                        bgcolor = flist->svc_color;
                } else {
                        fmt.color = res->entry_fg_color;
                        bgcolor = res->entry_bg_color;
                }
        } else {
                fmt.color = res->entry_fg_color;
                bgcolor = res->entry_bg_color;
        }

        /* Draw entry background */
        rect.p0 = pos;
        rect.p1.x = lrect.p1.x;
        rect.p1.y = rect.p0.y + line_height;

        rc = gfx_set_color(gc, bgcolor);
        if (rc != EOK)
                return rc;

        rc = gfx_fill_rect(gc, &rect);
        if (rc != EOK)
                return rc;

        /*
         * Make sure name does not overflow the entry rectangle.
         *
         * XXX We probably want to measure the text width, and,
         * if it's too long, use gfx_text_find_pos() to find where
         * it should be cut off (and append some sort of overflow
         * marker.
         */
        rc = gfx_set_clip_rect(gc, &rect);
        if (rc != EOK)
                return rc;

        pos.x += hpad;
        pos.y += vpad;

        if (res->textmode || !entry->isdir) {
                rc = gfx_puttext(&pos, &fmt, entry->name);
                if (rc != EOK) {
                        (void) gfx_set_clip_rect(gc, NULL);
                        return rc;
                }
        } else {
                /*
                 * XXX This is mostly a hack to distinguish directories
                 * util a better solution is available. (E.g. a Size
                 * column where we can put <dir>, an icon.)
                 */
                rv = asprintf(&caption, "[%s]", entry->name);
                if (rv < 0) {
                        (void) gfx_set_clip_rect(gc, NULL);
                        return rc;
                }

                rc = gfx_puttext(&pos, &fmt, caption);
                if (rc != EOK) {
                        free(caption);
                        (void) gfx_set_clip_rect(gc, NULL);
                        return rc;
                }

                free(caption);
        }

        return gfx_set_clip_rect(gc, NULL);
}

/** Paint file list.
 *
 * @param flist File list
 */
errno_t ui_file_list_paint(ui_file_list_t *flist)
{
        gfx_context_t *gc = ui_window_get_gc(flist->window);
        ui_resource_t *res = ui_window_get_res(flist->window);
        ui_file_list_entry_t *entry;
        int i, lines;
        errno_t rc;

        rc = gfx_set_color(gc, res->entry_bg_color);
        if (rc != EOK)
                return rc;

        rc = gfx_fill_rect(gc, &flist->rect);
        if (rc != EOK)
                return rc;

        if (!res->textmode) {
                rc = ui_paint_inset_frame(res, &flist->rect, NULL);
                if (rc != EOK)
                        return rc;
        }

        lines = ui_file_list_page_size(flist);
        i = 0;

        entry = flist->page;
        while (entry != NULL && i < lines) {
                rc = ui_file_list_entry_paint(entry, flist->page_idx + i);
                if (rc != EOK)
                        return rc;

                ++i;
                entry = ui_file_list_next(entry);
        }

        rc = gfx_update(gc);
        if (rc != EOK)
                return rc;

        return EOK;
}

/** Handle file list keyboard event.
 *
 * @param flist File list
 * @param event Keyboard event
 * @return ui_claimed iff event was claimed
 */
ui_evclaim_t ui_file_list_kbd_event(ui_file_list_t *flist, kbd_event_t *event)
{
        if (!flist->active)
                return ui_unclaimed;

        if (event->type == KEY_PRESS) {
                if ((event->mods & (KM_CTRL | KM_ALT | KM_SHIFT)) == 0) {
                        switch (event->key) {
                        case KC_UP:
                                ui_file_list_cursor_up(flist);
                                break;
                        case KC_DOWN:
                                ui_file_list_cursor_down(flist);
                                break;
                        case KC_HOME:
                                ui_file_list_cursor_top(flist);
                                break;
                        case KC_END:
                                ui_file_list_cursor_bottom(flist);
                                break;
                        case KC_PAGE_UP:
                                ui_file_list_page_up(flist);
                                break;
                        case KC_PAGE_DOWN:
                                ui_file_list_page_down(flist);
                                break;
                        case KC_ENTER:
                                ui_file_list_open(flist, flist->cursor);
                                break;
                        default:
                                break;
                        }
                }
        }

        return ui_claimed;
}

/** Handle file list position event.
 *
 * @param flist File list
 * @param event Position event
 * @return ui_claimed iff event was claimed
 */
ui_evclaim_t ui_file_list_pos_event(ui_file_list_t *flist, pos_event_t *event)
{
        gfx_coord2_t pos;
        gfx_rect_t irect;
        ui_file_list_entry_t *entry;
        gfx_coord_t line_height;
        size_t entry_idx;
        int n;

        line_height = ui_file_list_entry_height(flist);

        pos.x = event->hpos;
        pos.y = event->vpos;
        if (!gfx_pix_inside_rect(&pos, &flist->rect))
                return ui_unclaimed;

        if (!flist->active && event->type == POS_PRESS)
                ui_file_list_activate_req(flist);

        if (event->type == POS_PRESS || event->type == POS_DCLICK) {
                ui_file_list_inside_rect(flist, &irect);

                /* Did we click on one of the entries? */
                if (gfx_pix_inside_rect(&pos, &irect)) {
                        /* Index within page */
                        n = (pos.y - irect.p0.y) / line_height;

                        /* Entry and its index within entire listing */
                        entry = ui_file_list_page_nth_entry(flist, n, &entry_idx);
                        if (entry == NULL)
                                return ui_claimed;

                        if (event->type == POS_PRESS) {
                                /* Move to the entry found */
                                ui_file_list_cursor_move(flist, entry, entry_idx);
                        } else {
                                /* event->type == POS_DCLICK */
                                ui_file_list_open(flist, entry);
                        }
                } else {
                        /* It's in the border. */
                        if (event->type == POS_PRESS) {
                                /* Top or bottom half? */
                                if (pos.y >= (irect.p0.y + irect.p1.y) / 2)
                                        ui_file_list_page_down(flist);
                                else
                                        ui_file_list_page_up(flist);
                        }
                }
        }

        return ui_claimed;
}

/** Get base control for file list.
 *
 * @param flist File list
 * @return Base UI control
 */
ui_control_t *ui_file_list_ctl(ui_file_list_t *flist)
{
        return flist->control;
}

/** Set file list rectangle.
 *
 * @param flist File list
 * @param rect Rectangle
 */
void ui_file_list_set_rect(ui_file_list_t *flist, gfx_rect_t *rect)
{
        flist->rect = *rect;
}

/** Get file list page size.
 *
 * @param flist File list
 * @return Number of entries that fit in flist at the same time.
 */
unsigned ui_file_list_page_size(ui_file_list_t *flist)
{
        gfx_coord_t line_height;

        line_height = ui_file_list_entry_height(flist);
        return (flist->rect.p1.y - flist->rect.p0.y) / line_height;
}

void ui_file_list_inside_rect(ui_file_list_t *flist, gfx_rect_t *irect)
{
        ui_resource_t *res = ui_window_get_res(flist->window);

        if (res->textmode) {
                *irect = flist->rect;
        } else {
                ui_paint_get_inset_frame_inside(res, &flist->rect, irect);
        }
}

/** Determine if file list is active.
 *
 * @param flist File list
 * @return @c true iff file list is active
 */
bool ui_file_list_is_active(ui_file_list_t *flist)
{
        return flist->active;
}

/** Activate file list.
 *
 * @param flist File list
 *
 * @return EOK on success or an error code
 */
errno_t ui_file_list_activate(ui_file_list_t *flist)
{
        errno_t rc;

        if (flist->dir != NULL) {
                rc = vfs_cwd_set(flist->dir);
                if (rc != EOK)
                        return rc;
        }

        flist->active = true;
        (void) ui_file_list_paint(flist);
        return EOK;
}

/** Deactivate file list.
 *
 * @param flist File list
 */
void ui_file_list_deactivate(ui_file_list_t *flist)
{
        flist->active = false;
        (void) ui_file_list_paint(flist);
}

/** Initialize file list entry attributes.
 *
 * @param attr Attributes
 */
void ui_file_list_entry_attr_init(ui_file_list_entry_attr_t *attr)
{
        memset(attr, 0, sizeof(*attr));
}

/** Destroy file list control.
 *
 * @param arg Argument (ui_file_list_t *)
 */
void ui_file_list_ctl_destroy(void *arg)
{
        ui_file_list_t *flist = (ui_file_list_t *) arg;

        ui_file_list_destroy(flist);
}

/** Paint file list control.
 *
 * @param arg Argument (ui_file_list_t *)
 * @return EOK on success or an error code
 */
errno_t ui_file_list_ctl_paint(void *arg)
{
        ui_file_list_t *flist = (ui_file_list_t *) arg;

        return ui_file_list_paint(flist);
}

/** Handle file list control keyboard event.
 *
 * @param arg Argument (ui_file_list_t *)
 * @param kbd_event Keyboard event
 * @return @c ui_claimed iff the event is claimed
 */
ui_evclaim_t ui_file_list_ctl_kbd_event(void *arg, kbd_event_t *event)
{
        ui_file_list_t *flist = (ui_file_list_t *) arg;

        return ui_file_list_kbd_event(flist, event);
}

/** Handle file list control position event.
 *
 * @param arg Argument (ui_file_list_t *)
 * @param pos_event Position event
 * @return @c ui_claimed iff the event is claimed
 */
ui_evclaim_t ui_file_list_ctl_pos_event(void *arg, pos_event_t *event)
{
        ui_file_list_t *flist = (ui_file_list_t *) arg;

        return ui_file_list_pos_event(flist, event);
}

/** Append new file list entry.
 *
 * @param flist File list
 * @param attr Entry attributes
 * @return EOK on success or an error code
 */
errno_t ui_file_list_entry_append(ui_file_list_t *flist, ui_file_list_entry_attr_t *attr)
{
        ui_file_list_entry_t *entry;

        entry = calloc(1, sizeof(ui_file_list_entry_t));
        if (entry == NULL)
                return ENOMEM;

        entry->flist = flist;
        entry->name = str_dup(attr->name);
        if (entry->name == NULL) {
                free(entry);
                return ENOMEM;
        }

        entry->size = attr->size;
        entry->isdir = attr->isdir;
        entry->svc = attr->svc;
        link_initialize(&entry->lentries);
        list_append(&entry->lentries, &flist->entries);
        ++flist->entries_cnt;
        return EOK;
}

/** Delete file list entry.
 *
 * @param entry File list entry
 */
void ui_file_list_entry_delete(ui_file_list_entry_t *entry)
{
        if (entry->flist->cursor == entry)
                entry->flist->cursor = NULL;
        if (entry->flist->page == entry)
                entry->flist->page = NULL;

        list_remove(&entry->lentries);
        --entry->flist->entries_cnt;
        free((char *) entry->name);
        free(entry);
}

/** Clear file list entry list.
 *
 * @param flist File list
 */
void ui_file_list_clear_entries(ui_file_list_t *flist)
{
        ui_file_list_entry_t *entry;

        entry = ui_file_list_first(flist);
        while (entry != NULL) {
                ui_file_list_entry_delete(entry);
                entry = ui_file_list_first(flist);
        }
}

/** Read directory into file list entry list.
 *
 * @param flist File list
 * @param dirname Directory path
 * @return EOK on success or an error code
 */
errno_t ui_file_list_read_dir(ui_file_list_t *flist, const char *dirname)
{
        DIR *dir;
        struct dirent *dirent;
        vfs_stat_t finfo;
        char newdir[256];
        char *ndir = NULL;
        ui_file_list_entry_attr_t attr;
        ui_file_list_entry_t *next;
        ui_file_list_entry_t *prev;
        char *olddn;
        size_t pg_size;
        size_t max_idx;
        size_t i;
        errno_t rc;

        rc = vfs_cwd_set(dirname);
        if (rc != EOK)
                return rc;

        rc = vfs_cwd_get(newdir, sizeof(newdir));
        if (rc != EOK)
                return rc;

        ndir = str_dup(newdir);
        if (ndir == NULL)
                return ENOMEM;

        dir = opendir(".");
        if (dir == NULL) {
                rc = errno;
                goto error;
        }

        if (str_cmp(ndir, "/") != 0) {
                /* Need to add a synthetic up-dir entry */
                ui_file_list_entry_attr_init(&attr);
                attr.name = "..";
                attr.isdir = true;

                rc = ui_file_list_entry_append(flist, &attr);
                if (rc != EOK)
                        goto error;
        }

        dirent = readdir(dir);
        while (dirent != NULL) {
                rc = vfs_stat_path(dirent->d_name, &finfo);
                if (rc != EOK) {
                        /* Possibly a stale entry */
                        dirent = readdir(dir);
                        continue;
                }

                ui_file_list_entry_attr_init(&attr);
                attr.name = dirent->d_name;
                attr.size = finfo.size;
                attr.isdir = finfo.is_directory;
                attr.svc = finfo.service;

                rc = ui_file_list_entry_append(flist, &attr);
                if (rc != EOK)
                        goto error;

                dirent = readdir(dir);
        }

        closedir(dir);

        rc = ui_file_list_sort(flist);
        if (rc != EOK)
                goto error;

        flist->cursor = ui_file_list_first(flist);
        flist->cursor_idx = 0;
        flist->page = ui_file_list_first(flist);
        flist->page_idx = 0;

        /* Moving up? */
        if (str_cmp(dirname, "..") == 0) {
                /* Get the last component of old path */
                olddn = str_rchr(flist->dir, '/');
                if (olddn != NULL && *olddn != '\0') {
                        /* Find corresponding entry */
                        ++olddn;
                        next = ui_file_list_next(flist->cursor);
                        while (next != NULL && str_cmp(next->name, olddn) <= 0 &&
                            next->isdir) {
                                flist->cursor = next;
                                ++flist->cursor_idx;
                                next = ui_file_list_next(flist->cursor);
                        }

                        /* Move page so that cursor is in the center */
                        flist->page = flist->cursor;
                        flist->page_idx = flist->cursor_idx;

                        pg_size = ui_file_list_page_size(flist);

                        for (i = 0; i < pg_size / 2; i++) {
                                prev = ui_file_list_prev(flist->page);
                                if (prev == NULL)
                                        break;

                                flist->page = prev;
                                --flist->page_idx;
                        }

                        /* Make sure page is not beyond the end if possible */
                        if (flist->entries_cnt > pg_size)
                                max_idx = flist->entries_cnt - pg_size;
                        else
                                max_idx = 0;

                        while (flist->page_idx > 0 && flist->page_idx > max_idx) {
                                prev = ui_file_list_prev(flist->page);
                                if (prev == NULL)
                                        break;

                                flist->page = prev;
                                --flist->page_idx;
                        }
                }
        }

        free(flist->dir);
        flist->dir = ndir;

        return EOK;
error:
        (void) vfs_cwd_set(flist->dir);
        if (ndir != NULL)
                free(ndir);
        if (dir != NULL)
                closedir(dir);
        return rc;
}

/** Sort file list entries.
 *
 * @param flist File list
 * @return EOK on success, ENOMEM if out of memory
 */
errno_t ui_file_list_sort(ui_file_list_t *flist)
{
        ui_file_list_entry_t **emap;
        ui_file_list_entry_t *entry;
        size_t i;

        /* Create an array to hold pointer to each entry */
        emap = calloc(flist->entries_cnt, sizeof(ui_file_list_entry_t *));
        if (emap == NULL)
                return ENOMEM;

        /* Write entry pointers to array */
        entry = ui_file_list_first(flist);
        i = 0;
        while (entry != NULL) {
                assert(i < flist->entries_cnt);
                emap[i++] = entry;
                entry = ui_file_list_next(entry);
        }

        /* Sort the array of pointers */
        qsort(emap, flist->entries_cnt, sizeof(ui_file_list_entry_t *),
            ui_file_list_entry_ptr_cmp);

        /* Unlink entries from entry list */
        entry = ui_file_list_first(flist);
        while (entry != NULL) {
                list_remove(&entry->lentries);
                entry = ui_file_list_first(flist);
        }

        /* Add entries back to entry list sorted */
        for (i = 0; i < flist->entries_cnt; i++)
                list_append(&emap[i]->lentries, &flist->entries);

        free(emap);
        return EOK;
}

/** Compare two file list entries indirectly referenced by pointers.
 *
 * @param pa Pointer to pointer to first entry
 * @param pb Pointer to pointer to second entry
 * @return <0, =0, >=0 if pa < b, pa == pb, pa > pb, resp.
 */
int ui_file_list_entry_ptr_cmp(const void *pa, const void *pb)
{
        ui_file_list_entry_t *a = *(ui_file_list_entry_t **)pa;
        ui_file_list_entry_t *b = *(ui_file_list_entry_t **)pb;
        int dcmp;

        /* Sort directories first */
        dcmp = b->isdir - a->isdir;
        if (dcmp != 0)
                return dcmp;

        return str_cmp(a->name, b->name);
}

/** Return first file list entry.
 *
 * @param flist File list
 * @return First file list entry or @c NULL if there are no entries
 */
ui_file_list_entry_t *ui_file_list_first(ui_file_list_t *flist)
{
        link_t *link;

        link = list_first(&flist->entries);
        if (link == NULL)
                return NULL;

        return list_get_instance(link, ui_file_list_entry_t, lentries);
}

/** Return last file list entry.
 *
 * @param flist File list
 * @return Last file list entry or @c NULL if there are no entries
 */
ui_file_list_entry_t *ui_file_list_last(ui_file_list_t *flist)
{
        link_t *link;

        link = list_last(&flist->entries);
        if (link == NULL)
                return NULL;

        return list_get_instance(link, ui_file_list_entry_t, lentries);
}

/** Return next file list entry.
 *
 * @param cur Current entry
 * @return Next entry or @c NULL if @a cur is the last entry
 */
ui_file_list_entry_t *ui_file_list_next(ui_file_list_entry_t *cur)
{
        link_t *link;

        link = list_next(&cur->lentries, &cur->flist->entries);
        if (link == NULL)
                return NULL;

        return list_get_instance(link, ui_file_list_entry_t, lentries);
}

/** Return previous file list entry.
 *
 * @param cur Current entry
 * @return Previous entry or @c NULL if @a cur is the first entry
 */
ui_file_list_entry_t *ui_file_list_prev(ui_file_list_entry_t *cur)
{
        link_t *link;

        link = list_prev(&cur->lentries, &cur->flist->entries);
        if (link == NULL)
                return NULL;

        return list_get_instance(link, ui_file_list_entry_t, lentries);
}

/** Find the n-th entry of the current file list page.
 *
 * If the page is short and has less than n+1 entries, return the last entry.
 *
 * @param flist File list
 * @param n Which entry to get (starting from 0)
 * @param ridx Place to store index (within listing) of the entry
 * @return n-th entry of the page
 */
ui_file_list_entry_t *ui_file_list_page_nth_entry(ui_file_list_t *flist,
    size_t n, size_t *ridx)
{
        ui_file_list_entry_t *entry;
        ui_file_list_entry_t *next;
        size_t i;
        size_t idx;

        assert(n < ui_file_list_page_size(flist));

        entry = flist->page;
        if (entry == NULL)
                return NULL;

        idx = flist->page_idx;
        for (i = 0; i < n; i++) {
                next = ui_file_list_next(entry);
                if (next == NULL)
                        break;

                entry = next;
                ++idx;
        }

        *ridx = idx;
        return entry;
}

/** Move cursor to a new position, possibly scrolling.
 *
 * @param flist File list
 * @param entry New entry under cursor
 * @param entry_idx Index of new entry under cursor
 */
void ui_file_list_cursor_move(ui_file_list_t *flist,
    ui_file_list_entry_t *entry, size_t entry_idx)
{
        gfx_context_t *gc = ui_window_get_gc(flist->window);
        ui_file_list_entry_t *old_cursor;
        size_t old_idx;
        size_t rows;
        ui_file_list_entry_t *e;
        size_t i;

        rows = ui_file_list_page_size(flist);

        old_cursor = flist->cursor;
        old_idx = flist->cursor_idx;

        flist->cursor = entry;
        flist->cursor_idx = entry_idx;

        if (entry_idx >= flist->page_idx &&
            entry_idx < flist->page_idx + rows) {
                /*
                 * If cursor is still on the current page, we're not
                 * scrolling. Just unpaint old cursor and paint new
                 * cursor.
                 */
                ui_file_list_entry_paint(old_cursor, old_idx);
                ui_file_list_entry_paint(flist->cursor, flist->cursor_idx);

                (void) gfx_update(gc);
        } else {
                /*
                 * Need to scroll and update all rows.
                 */

                /* Scrolling up */
                if (entry_idx < flist->page_idx) {
                        flist->page = entry;
                        flist->page_idx = entry_idx;
                }

                /* Scrolling down */
                if (entry_idx >= flist->page_idx + rows) {
                        if (entry_idx >= rows) {
                                flist->page_idx = entry_idx - rows + 1;
                                /* Find first page entry (go back rows - 1) */
                                e = entry;
                                for (i = 0; i < rows - 1; i++) {
                                        e = ui_file_list_prev(e);
                                }

                                /* Should be valid */
                                assert(e != NULL);
                                flist->page = e;
                        } else {
                                flist->page = ui_file_list_first(flist);
                                flist->page_idx = 0;
                        }
                }

                (void) ui_file_list_paint(flist);
        }
}

/** Move cursor one entry up.
 *
 * @param flist File list
 */
void ui_file_list_cursor_up(ui_file_list_t *flist)
{
        ui_file_list_entry_t *prev;
        size_t prev_idx;

        prev = ui_file_list_prev(flist->cursor);
        prev_idx = flist->cursor_idx - 1;
        if (prev != NULL)
                ui_file_list_cursor_move(flist, prev, prev_idx);
}

/** Move cursor one entry down.
 *
 * @param flist File list
 */
void ui_file_list_cursor_down(ui_file_list_t *flist)
{
        ui_file_list_entry_t *next;
        size_t next_idx;

        next = ui_file_list_next(flist->cursor);
        next_idx = flist->cursor_idx + 1;
        if (next != NULL)
                ui_file_list_cursor_move(flist, next, next_idx);
}

/** Move cursor to top.
 *
 * @param flist File list
 */
void ui_file_list_cursor_top(ui_file_list_t *flist)
{
        ui_file_list_cursor_move(flist, ui_file_list_first(flist), 0);
}

/** Move cursor to bottom.
 *
 * @param flist File list
 */
void ui_file_list_cursor_bottom(ui_file_list_t *flist)
{
        ui_file_list_cursor_move(flist, ui_file_list_last(flist),
            flist->entries_cnt - 1);
}

/** Move one page up.
 *
 * @param flist File list
 */
void ui_file_list_page_up(ui_file_list_t *flist)
{
        gfx_context_t *gc = ui_window_get_gc(flist->window);
        ui_file_list_entry_t *old_page;
        ui_file_list_entry_t *old_cursor;
        size_t old_idx;
        size_t rows;
        ui_file_list_entry_t *entry;
        size_t i;

        rows = ui_file_list_page_size(flist);

        old_page = flist->page;
        old_cursor = flist->cursor;
        old_idx = flist->cursor_idx;

        /* Move page by rows entries up (if possible) */
        for (i = 0; i < rows; i++) {
                entry = ui_file_list_prev(flist->page);
                if (entry != NULL) {
                        flist->page = entry;
                        --flist->page_idx;
                }
        }

        /* Move cursor by rows entries up (if possible) */

        for (i = 0; i < rows; i++) {
                entry = ui_file_list_prev(flist->cursor);
                if (entry != NULL) {
                        flist->cursor = entry;
                        --flist->cursor_idx;
                }
        }

        if (flist->page != old_page) {
                /* We have scrolled. Need to repaint all entries */
                (void) ui_file_list_paint(flist);
        } else if (flist->cursor != old_cursor) {
                /* No scrolling, but cursor has moved */
                ui_file_list_entry_paint(old_cursor, old_idx);
                ui_file_list_entry_paint(flist->cursor, flist->cursor_idx);

                (void) gfx_update(gc);
        }
}

/** Move one page down.
 *
 * @param flist File list
 */
void ui_file_list_page_down(ui_file_list_t *flist)
{
        gfx_context_t *gc = ui_window_get_gc(flist->window);
        ui_file_list_entry_t *old_page;
        ui_file_list_entry_t *old_cursor;
        size_t old_idx;
        size_t max_idx;
        size_t rows;
        ui_file_list_entry_t *entry;
        size_t i;

        rows = ui_file_list_page_size(flist);

        old_page = flist->page;
        old_cursor = flist->cursor;
        old_idx = flist->cursor_idx;

        if (flist->entries_cnt > rows)
                max_idx = flist->entries_cnt - rows;
        else
                max_idx = 0;

        /* Move page by rows entries down (if possible) */
        for (i = 0; i < rows; i++) {
                entry = ui_file_list_next(flist->page);
                /* Do not scroll that results in a short page */
                if (entry != NULL && flist->page_idx < max_idx) {
                        flist->page = entry;
                        ++flist->page_idx;
                }
        }

        /* Move cursor by rows entries down (if possible) */

        for (i = 0; i < rows; i++) {
                entry = ui_file_list_next(flist->cursor);
                if (entry != NULL) {
                        flist->cursor = entry;
                        ++flist->cursor_idx;
                }
        }

        if (flist->page != old_page) {
                /* We have scrolled. Need to repaint all entries */
                (void) ui_file_list_paint(flist);
        } else if (flist->cursor != old_cursor) {
                /* No scrolling, but cursor has moved */
                ui_file_list_entry_paint(old_cursor, old_idx);
                ui_file_list_entry_paint(flist->cursor, flist->cursor_idx);

                (void) gfx_update(gc);
        }
}

/** Open file list entry.
 *
 * Perform Open action on a file list entry (e.g. switch to a subdirectory).
 *
 * @param flist File list
 * @param entry File list entry
 *
 * @return EOK on success or an error code
 */
errno_t ui_file_list_open(ui_file_list_t *flist, ui_file_list_entry_t *entry)
{
        if (entry->isdir)
                return ui_file_list_open_dir(flist, entry);
        else if (entry->svc == 0)
                return ui_file_list_open_file(flist, entry);
        else
                return EOK;
}

/** Open file list directory entry.
 *
 * Perform Open action on a directory entry (i.e. switch to the directory).
 *
 * @param flist File list
 * @param entry File list entry (which is a directory)
 *
 * @return EOK on success or an error code
 */
errno_t ui_file_list_open_dir(ui_file_list_t *flist,
    ui_file_list_entry_t *entry)
{
        gfx_context_t *gc = ui_window_get_gc(flist->window);
        char *dirname;
        errno_t rc;

        assert(entry->isdir);

        /*
         * Need to copy out name before we free the entry below
         * via ui_file_list_clear_entries().
         */
        dirname = str_dup(entry->name);
        if (dirname == NULL)
                return ENOMEM;

        ui_file_list_clear_entries(flist);

        rc = ui_file_list_read_dir(flist, dirname);
        if (rc != EOK) {
                free(dirname);
                return rc;
        }

        free(dirname);

        rc = ui_file_list_paint(flist);
        if (rc != EOK)
                return rc;

        return gfx_update(gc);
}

/** Open file list file entry.
 *
 * Perform Open action on a file entry (i.e. try running it).
 *
 * @param flist File list
 * @param entry File list entry (which is a file)
 *
 * @return EOK on success or an error code
 */
errno_t ui_file_list_open_file(ui_file_list_t *flist,
    ui_file_list_entry_t *entry)
{
        ui_file_list_selected(flist, entry->name);
        return EOK;
}

/** Request file list activation.
 *
 * Call back to request file list activation.
 *
 * @param flist File list
 */
void ui_file_list_activate_req(ui_file_list_t *flist)
{
        if (flist->cb != NULL && flist->cb->activate_req != NULL)
                flist->cb->activate_req(flist, flist->cb_arg);
}

/** Call back when a file is selected.
 *
 * @param flist File list
 * @param fname File name
 */
void ui_file_list_selected(ui_file_list_t *flist, const char *fname)
{
        if (flist->cb != NULL && flist->cb->selected != NULL)
                flist->cb->selected(flist, flist->cb_arg, fname);
}

/** @}
 */