#include "event.h"
#include "openbox.h"
#include "grab.h"
#include "framerender.h"
#include "client.h"
#include "config.h"
#include "frame.h"
#include "screen.h"
#include "group.h"
#include "prop.h"
#include "dispatch.h"
#include "focus.h"
#include "stacking.h"
#include "popup.h"

#include <X11/Xlib.h>
#include <glib.h>
#include <assert.h>

Client *focus_client = NULL;
GList **focus_order = NULL; /* these lists are created when screen_startup
                               sets the number of desktops */

Window focus_backup = None;

static Client *focus_cycle_target = NULL;
static Popup *focus_cycle_popup = NULL;

void focus_startup()
{
    /* create the window which gets focus when no clients get it. Have to
       make it override-redirect so we don't try manage it, since it is
       mapped. */
    XSetWindowAttributes attrib;

    focus_client = NULL;

    attrib.override_redirect = TRUE;
    focus_backup = XCreateWindow(ob_display, ob_root,
				 -100, -100, 1, 1, 0,
                                 CopyFromParent, InputOutput, CopyFromParent,
                                 CWOverrideRedirect, &attrib);
    XMapRaised(ob_display, focus_backup);

    /* do this *after* focus_backup is created, since it is used for
       stacking */
    focus_cycle_popup = popup_new(TRUE);

    /* start with nothing focused */
    focus_set_client(NULL);
}

void focus_shutdown()
{
    guint i;

    for (i = 0; i < screen_num_desktops; ++i)
        g_list_free(focus_order[i]);
    g_free(focus_order);
    focus_order = NULL;

    popup_free(focus_cycle_popup);
    focus_cycle_popup = NULL;

    XDestroyWindow(ob_display, focus_backup);

    /* reset focus to root */
    XSetInputFocus(ob_display, PointerRoot, RevertToPointerRoot,
                   event_lasttime);
}

static void push_to_top(Client *client)
{
    guint desktop;

    desktop = client->desktop;
    if (desktop == DESKTOP_ALL) desktop = screen_desktop;
    focus_order[desktop] = g_list_remove(focus_order[desktop], client);
    focus_order[desktop] = g_list_prepend(focus_order[desktop], client);
}

void focus_set_client(Client *client)
{
    Window active;
    Client *old;

#ifdef DEBUG_FOCUS
    g_message("focus_set_client 0x%lx", client ? client->window : 0);
#endif

    /* uninstall the old colormap, and install the new one */
    screen_install_colormap(focus_client, FALSE);
    screen_install_colormap(client, TRUE);

    if (client == NULL) {
	/* when nothing will be focused, send focus to the backup target */
	XSetInputFocus(ob_display, focus_backup, RevertToPointerRoot,
                       event_lasttime);
        XSync(ob_display, FALSE);
    }

    /* in the middle of cycling..? kill it. */
    if (focus_cycle_target)
        focus_cycle(TRUE, TRUE, TRUE, TRUE);

    old = focus_client;
    focus_client = client;

    /* move to the top of the list */
    if (client != NULL)
        push_to_top(client);

    /* set the NET_ACTIVE_WINDOW hint, but preserve it on shutdown */
    if (ob_state != State_Exiting) {
        active = client ? client->window : None;
        PROP_SET32(ob_root, net_active_window, window, active);
    }

    if (focus_client != NULL)
        dispatch_client(Event_Client_Focus, focus_client, 0, 0);
    if (old != NULL)
        dispatch_client(Event_Client_Unfocus, old, 0, 0);
}

static gboolean focus_under_pointer()
{
    int x, y;
    GList *it;

    if (ob_pointer_pos(&x, &y)) {
        for (it = stacking_list; it != NULL; it = it->next) {
            if (WINDOW_IS_CLIENT(it->data)) {
                Client *c = WINDOW_AS_CLIENT(it->data);
                if (c->desktop == screen_desktop &&
                    RECT_CONTAINS(c->frame->area, x, y))
                    break;
            }
        }
        if (it != NULL) {
            g_assert(WINDOW_IS_CLIENT(it->data));
            return client_normal(it->data) && client_focus(it->data);
        }
    }
    return FALSE;
}

/* finds the first transient that isn't 'skip' and ensure's that client_normal
 is true for it */
static Client *find_transient_recursive(Client *c, Client *top, Client *skip)
{
    GSList *it;
    Client *ret;

    for (it = c->transients; it; it = it->next) {
        if (it->data == top) return NULL;
        ret = find_transient_recursive(it->data, top, skip);
        if (ret && ret != skip && client_normal(ret)) return ret;
        if (it->data != skip && client_normal(it->data)) return it->data;
    }
    return NULL;
}

static gboolean focus_fallback_transient(Client *top, Client *old)
{
    Client *target = find_transient_recursive(top, top, old);
    if (!target) {
        /* make sure client_normal is true always */
        if (!client_normal(top))
            return FALSE;
        target = top; /* no transient, keep the top */
    }
    return client_focus(target);
}

void focus_fallback(FallbackType type)
{
    GList *it;
    Client *old = NULL;

    old = focus_client;

    /* unfocus any focused clients.. they can be focused by Pointer events
       and such, and then when I try focus them, I won't get a FocusIn event
       at all for them.
    */
    focus_set_client(NULL);

    if (!(type == Fallback_Desktop ?
          config_focus_last_on_desktop : config_focus_last)) {
        if (config_focus_follow) focus_under_pointer();
        return;
    }

    if (type == Fallback_Unfocusing && old) {
        /* try for transient relations */
        if (old->transient_for) {
            if (old->transient_for == TRAN_GROUP) {
                for (it = focus_order[screen_desktop]; it; it = it->next) {
                    GSList *sit;

                    for (sit = old->group->members; sit; sit = sit->next)
                        if (sit->data == it->data)
                            if (focus_fallback_transient(sit->data, old))
                                return;
                }
            } else {
                if (focus_fallback_transient(old->transient_for, old))
                    return;
            }
        }

        /* try for group relations */
        if (old->group) {
            GSList *sit;

            for (it = focus_order[screen_desktop]; it != NULL; it = it->next)
                for (sit = old->group->members; sit; sit = sit->next)
                    if (sit->data == it->data)
                        if (sit->data != old && client_normal(sit->data))
                            if (client_can_focus(sit->data)) {
                                gboolean r = client_focus(sit->data);
                                assert(r);
                                return;
                            }
        }
    }

    for (it = focus_order[screen_desktop]; it != NULL; it = it->next)
        if (type != Fallback_Unfocusing || it->data != old)
            if (client_normal(it->data) &&
                /* dont fall back to 'anonymous' fullscreen windows. theres no
                   checks for this is in transient/group fallbacks, so they can
                   be fallback targets there. */
                !((Client*)it->data)->fullscreen &&
                client_can_focus(it->data)) {
                gboolean r = client_focus(it->data);
                assert(r);
                return;
            }

    /* nothing to focus, and already set it to none above */
}

static void popup_cycle(Client *c, gboolean show)
{
    if (!show) {
        popup_hide(focus_cycle_popup);
    } else {
        Rect *a;
        Client *p = c;
        char *title;

        a = screen_physical_area_xinerama(0);
        popup_position(focus_cycle_popup, CenterGravity,
                       a->x + a->width / 2, a->y + a->height / 2);
/*        popup_size(focus_cycle_popup, a->height/2, a->height/16);
        popup_show(focus_cycle_popup, c->title,
                   client_icon(c, a->height/16, a->height/16));
*/
        /* XXX the size and the font extents need to be related on some level
         */
        popup_size(focus_cycle_popup, 320, 48);

        /* use the transient's parent's title/icon */
        while (p->transient_for && p->transient_for != TRAN_GROUP)
            p = p->transient_for;

        if (p == c)
            title = NULL;
        else
            title = g_strconcat((p->iconic ? p->icon_title : p->title),
                                " - ",
                                (c->iconic ? c->icon_title : c->title),
                                NULL);

        popup_show(focus_cycle_popup,
                   (title ? title : (c->iconic ? c->icon_title : c->title)),
                   client_icon(p, 48, 48));
        g_free(title);
    }
}

Client *focus_cycle(gboolean forward, gboolean linear, gboolean done,
                    gboolean cancel)
{
    static Client *first = NULL;
    static Client *t = NULL;
    static GList *order = NULL;
    GList *it, *start, *list;
    Client *ft;

    if (cancel) {
        if (focus_cycle_target)
            frame_adjust_focus(focus_cycle_target->frame, FALSE);
        if (focus_client)
            frame_adjust_focus(focus_client->frame, TRUE);
        goto done_cycle;
    } else if (done) {
        if (focus_cycle_target)
            client_activate(focus_cycle_target);
        goto done_cycle;
    }
    if (!first)
        grab_pointer(TRUE, None);

    if (!first) first = focus_client;
    if (!focus_cycle_target) focus_cycle_target = focus_client;

    if (linear) list = client_list;
    else        list = focus_order[screen_desktop];

    start = it = g_list_find(list, focus_cycle_target);
    if (!start) /* switched desktops or something? */
        start = it = forward ? g_list_last(list) : g_list_first(list);
    if (!start) goto done_cycle;

    do {
        if (forward) {
            it = it->next;
            if (it == NULL) it = g_list_first(list);
        } else {
            it = it->prev;
            if (it == NULL) it = g_list_last(list);
        }
        /*ft = client_focus_target(it->data);*/
        ft = it->data;
        /* we don't use client_can_focus here, because that doesn't let you
           focus an iconic window, but we want to be able to, so we just check
           if the focus flags on the window allow it, and its on the current
           desktop */
        if (ft->transients == NULL && client_normal(ft) &&
            ((ft->can_focus || ft->focus_notify) &&
             (ft->desktop == screen_desktop || ft->desktop == DESKTOP_ALL))) {
            if (ft != focus_cycle_target) { /* prevents flicker */
                if (focus_cycle_target)
                    frame_adjust_focus(focus_cycle_target->frame, FALSE);
                focus_cycle_target = ft;
                frame_adjust_focus(focus_cycle_target->frame, TRUE);
            }
            popup_cycle(ft, config_focus_popup);
            return ft;
        }
    } while (it != start);

done_cycle:
    t = NULL;
    first = NULL;
    focus_cycle_target = NULL;
    g_list_free(order);
    order = NULL;

    popup_cycle(ft, FALSE);
    grab_pointer(FALSE, None);

    return NULL;
}

void focus_order_add_new(Client *c)
{
    guint d, i;

    if (c->iconic)
        focus_order_to_top(c);
    else {
        d = c->desktop;
        if (d == DESKTOP_ALL) {
            for (i = 0; i < screen_num_desktops; ++i) {
                if (focus_order[i] && ((Client*)focus_order[i]->data)->iconic)
                    focus_order[i] = g_list_insert(focus_order[i], c, 0);
                else
                    focus_order[i] = g_list_insert(focus_order[i], c, 1);
            }
        } else
             if (focus_order[d] && ((Client*)focus_order[d]->data)->iconic)
                focus_order[d] = g_list_insert(focus_order[d], c, 0);
            else
                focus_order[d] = g_list_insert(focus_order[d], c, 1);
    }
}

void focus_order_remove(Client *c)
{
    guint d, i;

    d = c->desktop;
    if (d == DESKTOP_ALL) {
        for (i = 0; i < screen_num_desktops; ++i)
            focus_order[i] = g_list_remove(focus_order[i], c);
    } else
        focus_order[d] = g_list_remove(focus_order[d], c);
}

static void to_top(Client *c, guint d)
{
    focus_order[d] = g_list_remove(focus_order[d], c);
    if (!c->iconic) {
        focus_order[d] = g_list_prepend(focus_order[d], c);
    } else {
        GList *it;

        /* insert before first iconic window */
        for (it = focus_order[d];
             it && !((Client*)it->data)->iconic; it = it->next);
        g_list_insert_before(focus_order[d], it, c);
    }
}

void focus_order_to_top(Client *c)
{
    guint d, i;

    d = c->desktop;
    if (d == DESKTOP_ALL) {
        for (i = 0; i < screen_num_desktops; ++i)
            to_top(c, i);
    } else
        to_top(c, d);
}

static void to_bottom(Client *c, guint d)
{
    focus_order[d] = g_list_remove(focus_order[d], c);
    if (c->iconic) {
        focus_order[d] = g_list_append(focus_order[d], c);
    } else {
        GList *it;

        /* insert before first iconic window */
        for (it = focus_order[d];
             it && !((Client*)it->data)->iconic; it = it->next);
        g_list_insert_before(focus_order[d], it, c);
    }
}

void focus_order_to_bottom(Client *c)
{
    guint d, i;

    d = c->desktop;
    if (d == DESKTOP_ALL) {
        for (i = 0; i < screen_num_desktops; ++i)
            to_bottom(c, i);
    } else
        to_bottom(c, d);
}