#include "wm.h"

/* ── helpers ─────────────────────────────────────────────────────────── */

static void send_delete(WM *wm, Window win) {
    XEvent ev = {0};
    ev.xclient.type         = ClientMessage;
    ev.xclient.window       = win;
    ev.xclient.message_type = wm->wm_protocols;
    ev.xclient.format       = 32;
    ev.xclient.data.l[0]    = wm->wm_delete_window;
    ev.xclient.data.l[1]    = CurrentTime;
    XSendEvent(wm->dpy, win, False, NoEventMask, &ev);
}

static void set_cursor(WM *wm, Client *c, int x, int y) {
    Cursor cur;
    if (!c->maximized && frame_hit_resize(c, x, y)) cur = wm->cur_resize;
    else if (y < TITLE_HEIGHT)                       cur = wm->cur_move;
    else                                             cur = wm->cur_normal;
    XDefineCursor(wm->dpy, c->frame, cur);
}

/* ── snap on drag release ────────────────────────────────────────────── */

static void check_snap(WM *wm, Client *c) {
    int sw = DisplayWidth(wm->dpy, wm->screen);
    int sh = DisplayHeight(wm->dpy, wm->screen);

    if (c->x <= SNAP_DIST) {
        if (c->y <= SNAP_DIST) {
            client_maximize(wm, c);
        } else {
            client_snap_left(wm, c);
        }
    } else if (c->x + (int)(c->w + BORDER_W * 2) >= sw - DESKBAR_W - SNAP_DIST) {
        client_snap_right(wm, c);
    } else if (c->y <= SNAP_DIST) {
        client_maximize(wm, c);
    } else {
        (void)sh;
    }
}

/* ── event handlers ──────────────────────────────────────────────────── */

void on_map_request(WM *wm, XMapRequestEvent *e) {
    client_add(wm, e->window);
}

void on_unmap_notify(WM *wm, XUnmapEvent *e) {
    if (e->send_event) return;
    Client *c = client_find_by_win(wm, e->window);
    if (c && !c->minimized) client_remove(wm, e->window);
}

void on_destroy_notify(WM *wm, XDestroyWindowEvent *e) {
    Client *c = client_find_by_win(wm, e->window);
    if (!c) c = client_find_by_frame(wm, e->window);
    if (c)  client_remove(wm, c->win);
}

void on_expose(WM *wm, XExposeEvent *e) {
    if (e->count != 0) return;
    if (wm->menu_visible && e->window == wm->menu_win) {
        menu_draw(wm);
        return;
    }
    if (wm->swl_visible && e->window == wm->swl_win) {
        switcher_draw(wm);
        return;
    }
    Client *c = client_find_by_frame(wm, e->window);
    if (c && !c->minimized) frame_draw(wm, c);
}


void on_configure_request(WM *wm, XConfigureRequestEvent *e) {
    Client *c = client_find_by_win(wm, e->window);
    XWindowChanges wc;
    wc.x = e->x; wc.y = e->y;
    wc.width = e->width; wc.height = e->height;
    wc.border_width = e->border_width;
    wc.sibling = e->above; wc.stack_mode = e->detail;
    if (c && !c->maximized) {
        c->w = e->width; c->h = e->height;
        XResizeWindow(wm->dpy, c->frame,
                      c->w + BORDER_W*2, c->h + TITLE_HEIGHT + BORDER_W);
    }
    XConfigureWindow(wm->dpy, e->window, e->value_mask, &wc);
}

void on_enter_notify(WM *wm, XCrossingEvent *e) {
    Client *c = client_find_by_frame(wm, e->window);
    if (c && !c->minimized) set_cursor(wm, c, e->x, e->y);
}

static void wm_switch_desktop(WM *wm, int new_desk) {
    if (new_desk < 0 || new_desk >= 4 || new_desk == wm->cur_desktop) return;

    /* hide windows on old desktop */
    for (Client *c = wm->clients; c; c = c->next) {
        if (!c->minimized && c->desktop == wm->cur_desktop)
            XUnmapWindow(wm->dpy, c->frame);
    }

    wm->cur_desktop = new_desk;

    /* show windows on new desktop */
    for (Client *c = wm->clients; c; c = c->next) {
        if (!c->minimized && c->desktop == new_desk)
            XMapWindow(wm->dpy, c->frame);
    }

    /* update focus */
    if (wm->focused && wm->focused->desktop != new_desk) {
        wm->focused->focused = 0;
        frame_draw(wm, wm->focused);
        wm->focused = NULL;
    }
    if (!wm->focused) {
        for (Client *c = wm->clients; c; c = c->next) {
            if (!c->minimized && c->desktop == new_desk) {
                client_focus(wm, c);
                break;
            }
        }
    }

    /* advertise new desktop */
    long nd = new_desk;
    XChangeProperty(wm->dpy, wm->root, wm->net_current_desktop, XA_CARDINAL, 32,
                    PropModeReplace, (unsigned char *)&nd, 1);
}

void on_client_message(WM *wm, XClientMessageEvent *e) {
    Atom net_active       = XInternAtom(wm->dpy, "_NET_ACTIVE_WINDOW",  False);
    Atom net_close        = XInternAtom(wm->dpy, "_NET_CLOSE_WINDOW",   False);
    Atom wm_change_state  = XInternAtom(wm->dpy, "WM_CHANGE_STATE",     False);
    Atom net_wm_desktop   = XInternAtom(wm->dpy, "_NET_WM_DESKTOP",     False);

    /* _NET_CURRENT_DESKTOP → switch virtual desktop */
    if (e->message_type == wm->net_current_desktop && e->window == wm->root) {
        wm_switch_desktop(wm, (int)e->data.l[0]);
        return;
    }

    /* _NET_WM_DESKTOP → move window to desktop */
    if (e->message_type == net_wm_desktop) {
        Client *c = client_find_by_win(wm, e->window);
        if (c) client_move_to_desktop(wm, c, (int)e->data.l[0]);
        return;
    }

    if (e->message_type == net_active) {
        Client *c = client_find_by_win(wm, e->window);
        if (c) client_restore(wm, c);
        return;
    }
    if (e->message_type == net_close) {
        Client *c = client_find_by_win(wm, e->window);
        if (c) {
            XEvent ev = {0};
            ev.xclient.type         = ClientMessage;
            ev.xclient.window       = c->win;
            ev.xclient.message_type = wm->wm_protocols;
            ev.xclient.format       = 32;
            ev.xclient.data.l[0]    = wm->wm_delete_window;
            ev.xclient.data.l[1]    = CurrentTime;
            XSendEvent(wm->dpy, c->win, False, NoEventMask, &ev);
        }
        return;
    }
    /* WM_CHANGE_STATE IconicState → minimize */
    if (e->message_type == wm_change_state && e->data.l[0] == 3) {
        Client *c = client_find_by_win(wm, e->window);
        if (c && !c->minimized) client_minimize(wm, c);
        return;
    }
}

/* Called when a managed window changes a property (title, etc.) */
void on_property_notify(WM *wm, XPropertyEvent *e) {
    Client *c = client_find_by_win(wm, e->window);
    if (!c || c->minimized) return;

    Atom wm_name     = XInternAtom(wm->dpy, "WM_NAME",     False);
    Atom net_wm_name = XInternAtom(wm->dpy, "_NET_WM_NAME", False);
    Atom utf8        = XInternAtom(wm->dpy, "UTF8_STRING",  False);

    if (e->atom != wm_name && e->atom != net_wm_name) return;

    /* re-fetch title */
    char new_title[256] = {0};
    {
        Atom type; int fmt; unsigned long n, after;
        unsigned char *data = NULL;
        if (XGetWindowProperty(wm->dpy, c->win, net_wm_name, 0, 256, False,
                               utf8, &type, &fmt, &n, &after, &data)
            == Success && data && n > 0) {
            snprintf(new_title, 255, "%.*s", (int)n, data);
            XFree(data);
        } else {
            if (data) XFree(data);
            char *name = NULL;
            if (XFetchName(wm->dpy, c->win, &name) && name) {
                strncpy(new_title, name, 255);
                XFree(name);
            }
        }
    }

    if (new_title[0] && strcmp(new_title, c->title) != 0) {
        strncpy(c->title, new_title, 255);
        frame_draw(wm, c);
    }
}

void on_button_press(WM *wm, XButtonEvent *e) {
    /* Exposé — click on any frame to select and exit */
    if (wm->expose_active) {
        Client *c = client_find_by_frame(wm, e->window);
        if (c) expose_hide(wm, c->frame);
        else   expose_hide(wm, None);
        return;
    }

    /* menu window */
    if (wm->menu_visible && e->window == wm->menu_win) {
        if (e->button == Button1) menu_click(wm, e->x, e->y);
        else                      menu_hide(wm);
        return;
    }
    /* right-click root → menu */
    if (e->window == wm->root && e->button == Button3) {
        menu_show(wm, e->x_root, e->y_root);
        return;
    }
    if (wm->menu_visible) { menu_hide(wm); return; }

    Client *c = client_find_by_frame(wm, e->window);
    if (!c || c->minimized) return;

    client_focus(wm, c);
    if (e->button != Button1) return;

    if (frame_hit_close(c, e->x, e->y)) {
        send_delete(wm, c->win);
        return;
    }
    if (frame_hit_maximize(c, e->x, e->y)) {
        client_toggle_maximize(wm, c);
        return;
    }
    if (frame_hit_minimize(c, e->x, e->y)) {
        client_minimize(wm, c);
        return;
    }
    if (!c->maximized && frame_hit_resize(c, e->x, e->y)) {
        wm->drag_mode    = DRAG_RESIZE;
        wm->drag_frame   = c->frame;
        wm->drag_start_x = e->x_root;
        wm->drag_start_y = e->y_root;
        wm->drag_win_w   = c->w;
        wm->drag_win_h   = c->h;
        XGrabPointer(wm->dpy, c->frame, False,
                     ButtonReleaseMask | PointerMotionMask,
                     GrabModeAsync, GrabModeAsync,
                     None, wm->cur_resize, CurrentTime);
        return;
    }
    if (e->y < TITLE_HEIGHT) {
        /* double-click title bar → maximize toggle */
        if (e->time - c->last_click_time < DBL_CLICK_MS) {
            client_toggle_maximize(wm, c);
            c->last_click_time = 0;
            return;
        }
        c->last_click_time = e->time;

        if (c->maximized) return;  /* don't drag a maximized window */

        wm->drag_mode    = DRAG_MOVE;
        wm->drag_frame   = c->frame;
        wm->drag_start_x = e->x_root;
        wm->drag_start_y = e->y_root;
        wm->drag_win_x   = c->x;
        wm->drag_win_y   = c->y;
        XGrabPointer(wm->dpy, c->frame, False,
                     ButtonReleaseMask | PointerMotionMask,
                     GrabModeAsync, GrabModeAsync,
                     None, wm->cur_move, CurrentTime);
    }
}

void on_button_release(WM *wm, XButtonEvent *e) {
    (void)e;
    if (wm->drag_mode == DRAG_MOVE) {
        /* snap check after move */
        Client *c = client_find_by_frame(wm, wm->drag_frame);
        if (c) check_snap(wm, c);
    }
    if (wm->drag_mode != DRAG_NONE) {
        wm->drag_mode = DRAG_NONE;
        XUngrabPointer(wm->dpy, CurrentTime);
    }
}

void on_motion_notify(WM *wm, XMotionEvent *e) {
    if (wm->menu_visible && e->window == wm->menu_win) {
        int idx = menu_item_at(e->y);
        if (idx != wm->menu_hovered) {
            wm->menu_hovered = idx;
            menu_draw(wm);
        }
        return;
    }
    if (wm->drag_mode == DRAG_NONE) {
        Client *c = client_find_by_frame(wm, e->window);
        if (c) set_cursor(wm, c, e->x, e->y);
        return;
    }
    Client *c = client_find_by_frame(wm, wm->drag_frame);
    if (!c) return;
    int dx = e->x_root - wm->drag_start_x;
    int dy = e->y_root - wm->drag_start_y;
    if (wm->drag_mode == DRAG_MOVE) {
        c->x = wm->drag_win_x + dx;
        c->y = wm->drag_win_y + dy;
        if (c->y < 0) c->y = 0;  /* don't drag above screen top */
        XMoveWindow(wm->dpy, c->frame, c->x, c->y);
    } else {
        int nw = (int)wm->drag_win_w + dx;
        int nh = (int)wm->drag_win_h + dy;
        /* clamp to minimum */
        if (nw < c->min_w) nw = c->min_w;
        if (nh < c->min_h) nh = c->min_h;
        /* snap to resize-increment grid (e.g. terminal character cells) */
        if (c->inc_w > 1) {
            nw = c->base_w + ((nw - c->base_w) / c->inc_w) * c->inc_w;
            if (nw < c->min_w) nw += c->inc_w;
        }
        if (c->inc_h > 1) {
            nh = c->base_h + ((nh - c->base_h) / c->inc_h) * c->inc_h;
            if (nh < c->min_h) nh += c->inc_h;
        }
        c->w = (unsigned)nw; c->h = (unsigned)nh;
        XResizeWindow(wm->dpy, c->frame, c->w+BORDER_W*2, c->h+TITLE_HEIGHT+BORDER_W);
        XResizeWindow(wm->dpy, c->win, c->w, c->h);
        frame_draw(wm, c);
    }
}

void on_key_press(WM *wm, XKeyEvent *e) {
    KeySym sym = XLookupKeysym(e, 0);

    /* Alt+F4 — close focused window */
    if ((e->state & Mod1Mask) && sym == XK_F4 && wm->focused)
        send_delete(wm, wm->focused->win);

    /* Alt+Tab / Shift+Alt+Tab — visual switcher */
    if ((e->state & Mod1Mask) && sym == XK_Tab) {
        int backward = (e->state & ShiftMask) != 0;
        if (wm->swl_visible) {
            if (backward) switcher_prev(wm);
            else          switcher_next(wm);
        } else if (wm->clients) {
            switcher_show(wm);
            if (backward && wm->swl_visible) {
                wm->swl_idx = wm->swl_count - 1;
                switcher_draw(wm);
            }
        }
        return;
    }

    /* While switcher is visible, eat all other keys until Alt released */
    if (wm->swl_visible) {
        if (sym == XK_Escape) switcher_hide(wm, 0);
        return;
    }

    /* Alt+F9 — minimize */
    if ((e->state & Mod1Mask) && sym == XK_F9 && wm->focused)
        client_minimize(wm, wm->focused);

    /* Alt+F10 — maximize toggle */
    if ((e->state & Mod1Mask) && sym == XK_F10 && wm->focused)
        client_toggle_maximize(wm, wm->focused);

    /* Alt+F1 — launcher */
    if ((e->state & Mod1Mask) && sym == XK_F1)
        system("orionlauncher &");

    /* PrintScreen — screenshot */
    if (sym == XK_Print) {
        if (e->state & ShiftMask)
            system("orionshot region &");
        else
            system("orionshot full &");
    }

    /* XF86 media keys */
    if (sym == XF86XK_AudioRaiseVolume)
        system("pactl set-sink-volume @DEFAULT_SINK@ +5% 2>/dev/null; "
               "pactl get-sink-volume @DEFAULT_SINK@ 2>/dev/null | "
               "grep -oP '[0-9]+%' | head -1 | "
               "xargs -I{} notify-send -t 1500 'Volume' '{}' 2>/dev/null &");
    if (sym == XF86XK_AudioLowerVolume)
        system("pactl set-sink-volume @DEFAULT_SINK@ -5% 2>/dev/null; "
               "pactl get-sink-volume @DEFAULT_SINK@ 2>/dev/null | "
               "grep -oP '[0-9]+%' | head -1 | "
               "xargs -I{} notify-send -t 1500 'Volume' '{}' 2>/dev/null &");
    if (sym == XF86XK_AudioMute)
        system("pactl set-sink-mute @DEFAULT_SINK@ toggle 2>/dev/null; "
               "notify-send -t 1500 'Volume' 'Muted toggled' 2>/dev/null &");
    if (sym == XF86XK_AudioPlay)
        system("playerctl play-pause 2>/dev/null &");
    if (sym == XF86XK_AudioNext)
        system("playerctl next 2>/dev/null &");
    if (sym == XF86XK_AudioPrev)
        system("playerctl previous 2>/dev/null &");
    if (sym == XF86XK_MonBrightnessUp)
        system("brightnessctl set +10% 2>/dev/null; "
               "notify-send -t 1200 'Brightness' "
               "\"$(brightnessctl g 2>/dev/null)\" 2>/dev/null &");
    if (sym == XF86XK_MonBrightnessDown)
        system("brightnessctl set 10%- 2>/dev/null; "
               "notify-send -t 1200 'Brightness' "
               "\"$(brightnessctl g 2>/dev/null)\" 2>/dev/null &");

    /* Super+V — clipboard manager */
    if ((e->state & Mod4Mask) && sym == XK_v)
        system("orionclip --show &");

    /* Super+Left — snap left */
    if ((e->state & Mod4Mask) && sym == XK_Left && wm->focused)
        client_snap_left(wm, wm->focused);

    /* Super+Right — snap right */
    if ((e->state & Mod4Mask) && sym == XK_Right && wm->focused)
        client_snap_right(wm, wm->focused);

    /* Super+Up — maximize */
    if ((e->state & Mod4Mask) && sym == XK_Up && wm->focused)
        client_maximize(wm, wm->focused);

    /* Super+Down — unmaximize / restore */
    if ((e->state & Mod4Mask) && sym == XK_Down && wm->focused)
        client_unmaximize(wm, wm->focused);

    /* Super+Space — Exposé window overview */
    if ((e->state & Mod4Mask) && sym == XK_space) {
        if (wm->expose_active) expose_hide(wm, None);
        else                   expose_show(wm);
        return;
    }

    /* Super+1-4 — switch to desktop N */
    if ((e->state & Mod4Mask) && !(e->state & ShiftMask)) {
        int desk = -1;
        if (sym == XK_1) desk = 0;
        else if (sym == XK_2) desk = 1;
        else if (sym == XK_3) desk = 2;
        else if (sym == XK_4) desk = 3;
        if (desk >= 0) {
            if (wm->expose_active) expose_hide(wm, None);
            wm_switch_desktop(wm, desk);
            return;
        }
    }

    /* Super+Shift+1-4 — move focused window to desktop N */
    if ((e->state & Mod4Mask) && (e->state & ShiftMask) && wm->focused) {
        int desk = -1;
        if (sym == XK_1) desk = 0;
        else if (sym == XK_2) desk = 1;
        else if (sym == XK_3) desk = 2;
        else if (sym == XK_4) desk = 3;
        if (desk >= 0) {
            client_move_to_desktop(wm, wm->focused, desk);
            return;
        }
    }

    /* Escape — hide menu or exit Exposé */
    if (sym == XK_Escape) {
        if (wm->expose_active) expose_hide(wm, None);
        else if (wm->menu_visible) menu_hide(wm);
    }
}

void on_key_release(WM *wm, XKeyEvent *e) {
    if (!wm->swl_visible) return;
    KeySym sym = XLookupKeysym(e, 0);
    if (sym == XK_Alt_L || sym == XK_Alt_R ||
        sym == XK_Meta_L || sym == XK_Meta_R)
        switcher_hide(wm, 1);
}