/*
 Copyright (C) 2009-2013 Christian Dywan <christian@twotoasts.de>
 Copyright (C) 2010 Samuel Creshal <creshal@arcor.de>

 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.

 See the file COPYING for the full license text.
*/

#include <midori/midori.h>

static GdkColor
view_get_bgcolor_for_hostname (MidoriView* view, gchar* hostname)
{
    GdkColor color;
    GdkPixbuf* icon = midori_view_get_icon (view);
    if (icon != NULL)
    {
        GdkPixbuf* newpix;
        guchar* pixels;

        newpix = gdk_pixbuf_scale_simple (icon, 1, 1, GDK_INTERP_BILINEAR);
        pixels = gdk_pixbuf_get_pixels (newpix);
        color.red = pixels[0] * 255;
        color.green = pixels[1] * 255;
        color.blue = pixels[2] * 255;
    }
    else
    {
        gchar* hash, *colorstr;

        hash = g_compute_checksum_for_string (G_CHECKSUM_MD5, hostname, 1);
        colorstr = g_strndup (hash, 6 + 1);
        colorstr[0] = '#';
        gdk_color_parse (colorstr, &color);

        g_free (hash);
        g_free (colorstr);
    }

    if ((color.red   < 35000)
     && (color.green < 35000)
     && (color.blue  < 35000))
    {
        color.red   += 20000;
        color.green += 20000;
        color.blue  += 20000;
    }

    if (color.red < 10000)
        color.red = 5000;
    else
        color.red -= 5000;
    if (color.blue < 10000)
        color.blue = 5000;
    else
        color.blue -= 5000;
    if (color.green < 10000)
        color.green = 5000;
    else
        color.green -= 5000;

    return color;
}

static void
colorful_tabs_view_notify_uri_cb (MidoriView*      view,
                                  GParamSpec*      pspec,
                                  MidoriExtension* extension)
{
    gchar* hostname;
    GdkColor color;
    GdkColor fgcolor;

    if (!midori_uri_is_blank (midori_view_get_display_uri (view))
      && (hostname = midori_uri_parse_hostname (midori_view_get_display_uri (view), NULL))
      && midori_view_get_icon_uri (view) != NULL)
    {
        color = view_get_bgcolor_for_hostname (view, hostname);
        g_free (hostname);
        /* Ensure high contrast by enforcing black/ white text colour. */
        if ((color.red   < 41000)
         && (color.green < 41000)
         && (color.blue  < 41000))
            gdk_color_parse ("#fff", &fgcolor);
        else
            gdk_color_parse ("#000", &fgcolor);

        midori_view_set_colors (view, &fgcolor, &color);
    }
    else
        midori_view_set_colors (view, NULL, NULL);
}

static void
colorful_tabs_browser_add_tab_cb (MidoriBrowser*   browser,
                                  GtkWidget*       view,
                                  MidoriExtension* extension)
{
    colorful_tabs_view_notify_uri_cb (MIDORI_VIEW (view), NULL, extension);
    g_signal_connect (view, "notify::icon",
        G_CALLBACK (colorful_tabs_view_notify_uri_cb), extension);
}

static void
colorful_tabs_app_add_browser_cb (MidoriApp*       app,
                                  MidoriBrowser*   browser,
                                  MidoriExtension* extension);

static void
colorful_tabs_deactivate_cb (MidoriExtension* extension,
                             MidoriBrowser*   browser)
{
    GList* children;
    GtkWidget* view;
    MidoriApp* app = midori_extension_get_app (extension);

    g_signal_handlers_disconnect_by_func (
        app, colorful_tabs_app_add_browser_cb, extension);
    g_signal_handlers_disconnect_by_func (
        browser, colorful_tabs_browser_add_tab_cb, extension);
    g_signal_handlers_disconnect_by_func (
        extension, colorful_tabs_deactivate_cb, browser);

    children = midori_browser_get_tabs (MIDORI_BROWSER (browser));
    for (; children; children = g_list_next (children))
    {
        midori_view_set_colors (children->data, NULL, NULL);
        g_signal_handlers_disconnect_by_func (
            children->data, colorful_tabs_view_notify_uri_cb, extension);
    }
    g_list_free (children);
}

static void
colorful_tabs_app_add_browser_cb (MidoriApp*       app,
                                  MidoriBrowser*   browser,
                                  MidoriExtension* extension)
{
    GList* children;

    children = midori_browser_get_tabs (MIDORI_BROWSER (browser));
    for (; children; children = g_list_next (children))
        colorful_tabs_browser_add_tab_cb (browser, children->data, extension);
    g_list_free (children);

    g_signal_connect (browser, "add-tab",
        G_CALLBACK (colorful_tabs_browser_add_tab_cb), extension);
    g_signal_connect (extension, "deactivate",
        G_CALLBACK (colorful_tabs_deactivate_cb), browser);
}


static void
colorful_tabs_activate_cb (MidoriExtension* extension,
                           MidoriApp*       app)
{
    KatzeArray* browsers;
    MidoriBrowser* browser;

    browsers = katze_object_get_object (app, "browsers");
    KATZE_ARRAY_FOREACH_ITEM (browser, browsers)
        colorful_tabs_app_add_browser_cb (app, browser, extension);
    g_signal_connect (app, "add-browser",
        G_CALLBACK (colorful_tabs_app_add_browser_cb), extension);

    g_object_unref (browsers);
}

MidoriExtension*
extension_init (void)
{
    MidoriExtension* extension = g_object_new (MIDORI_TYPE_EXTENSION,
        "name", _("Colorful Tabs"),
        "description", _("Tint each tab distinctly"),
        "version", "0.5" MIDORI_VERSION_SUFFIX,
        "authors", "Christian Dywan <christian@twotoasts.de>, Samuel Creshal <creshal@arcor.de>",
        NULL);

    g_signal_connect (extension, "activate",
        G_CALLBACK (colorful_tabs_activate_cb), NULL);

    return extension;
}