#include "input.h"
#include "file.h"
#include "image.h"
#include "window.h"
#include <gtk-3.0/gtk/gtk.h>

#define TIMEOUT 20
#define SCROLLAMMOUNT 30

int grabbed = 0;
gdouble start_x, start_y;

void next()
{
    char *name;
    if ((name = get_next_file()) != NULL)
        load_image(name);
}

void prev()
{
    char *name;
    if ((name = get_prev_file()) != NULL)
        load_image(name);
}

void first()
{
    char *name;
    if ((name = get_first_file()) != NULL)
        load_image(name);
}

void last()
{
    char *name;
    if ((name = get_last_file()) != NULL)
        load_image(name);
}

void handle_key_press(GdkEvent *event)
{
    GdkModifierType state;
    gdk_event_get_state(event, &state);

    switch (event->key.keyval) {
    case GDK_KEY_q:
        quit();
        break;
    case GDK_KEY_w:
        fit_image();
        break;
    case GDK_KEY_plus:
    case GDK_KEY_KP_Add:
        zoom(1);
        break;
    case GDK_KEY_minus:
    case GDK_KEY_KP_Subtract:
        zoom(-1);
        break;
    case GDK_KEY_equal:
        zoom(0);
        break;
    case GDK_KEY_n:
        next();
        break;
    case GDK_KEY_p:
        prev();
        break;
    case GDK_KEY_Up:
        if (curr_scale_mod == fit || state & GDK_SHIFT_MASK)
            prev();
        else
            scroll_window(0, -SCROLLAMMOUNT);
        break;
    case GDK_KEY_Down:
        if (curr_scale_mod == fit || state & GDK_SHIFT_MASK)
            next();
        else
            scroll_window(0, SCROLLAMMOUNT);
        break;
    case GDK_KEY_Right:
        if (curr_scale_mod == fit || state & GDK_SHIFT_MASK)
            next();
        else
            scroll_window(SCROLLAMMOUNT, 0);
        break;
    case GDK_KEY_Left:
        if (curr_scale_mod == fit || state & GDK_SHIFT_MASK)
            prev();
        else
            scroll_window(-SCROLLAMMOUNT, 0);
        break;
    case GDK_KEY_j:
        if (curr_scale_mod == fit)
            next();
        else
            scroll_window(0, SCROLLAMMOUNT);
        break;
    case GDK_KEY_J:
        next();
        break;
    case GDK_KEY_k:
        if (curr_scale_mod == fit)
            prev();
        else
            scroll_window(0, -SCROLLAMMOUNT);
        break;
    case GDK_KEY_K:
        prev();
        break;
    case GDK_KEY_l:
        if (curr_scale_mod == fit)
            next();
        else
            scroll_window(SCROLLAMMOUNT, 0);
        break;
    case GDK_KEY_L:
        next();
        break;
    case GDK_KEY_h:
        if (curr_scale_mod == fit)
            prev();
        else
            scroll_window(-SCROLLAMMOUNT, 0);
        break;
    case GDK_KEY_H:
        prev();
        break;
    case GDK_KEY_g:
    case GDK_KEY_Home:
        first();
        break;
    case GDK_KEY_G:
    case GDK_KEY_End:
        last();
        break;
    case GDK_KEY_f:
        toggle_fullscreen();
        break;
    default:
        break;
    }
}

void handle_button_press(GdkEvent *event)
{
    if (event->type == GDK_2BUTTON_PRESS)
        toggle_fullscreen();
    else {
        grabbed = 1;
        start_x = event->motion.x;
        start_y = event->motion.y;
    }
}

void handle_button_release()
{
    grabbed = 0;
}

void handle_mouse_move(gdouble x, gdouble y)
{
    if (grabbed) {
        gdouble diff_x = start_x - x;
        gdouble diff_y = start_y - y;
        start_x = x;
        start_y = y;
        scroll_window(diff_x, diff_y);
    }
}

void handle_scroll(GdkEvent *event)
{
    GdkModifierType state;
    gdk_event_get_state(event, &state);

    switch (event->scroll.direction) {
    case GDK_SCROLL_UP:
        if (state & GDK_CONTROL_MASK) {
            zoom(1);
        } else {
            prev();
        }
        break;
    case GDK_SCROLL_DOWN:
        if (state & GDK_CONTROL_MASK) {
            zoom(-1);
        } else {
            next();
        }
        break;
    default:
        break;
    }
}

gboolean resize_done(gpointer data)
{
    guint *id = data;
    *id = 0;
    fit_image();
    return FALSE;
}

void handle_resize()
{
    if (curr_scale_mod != fit)
        return;
    static guint id = 0;
    if (id)
        g_source_remove(id);
    id = g_timeout_add(TIMEOUT, resize_done, &id);
}