/*
   ui/widget.cc
   This file is part of the Osirion project and is distributed under
   the terms of the GNU General Public License version 2
*/

#include "auxiliary/functions.h"
#include "sys/sys.h"
#include "ui/paint.h"
#include "ui/ui.h"
#include "ui/widget.h"

#include <cassert>

namespace ui
{

Widget::Widget(Widget *parent)
{
	widget_focus = false;
	widget_visible = true;
	widget_border = true;
	widget_background = false;
	widget_enabled = true;
	widget_palette = 0;
	widget_font = 0;
	widget_label.assign("widget");

	if (!parent) {
		widget_parent = root();
	} else {
		widget_parent = parent;
	}

	if (widget_parent)
		widget_parent->add_child(this);
}

Widget::~Widget()
{
	remove_children();
}

void Widget::remove_children()
{
	for (Children::iterator it = widget_children.begin(); it != widget_children.end(); it++) {
		delete(*it);
		(*it) = 0;
	}
	widget_children.clear();
}

bool Widget::is_child(const Widget *widget) const
{
	for (Children::const_iterator it = widget_children.begin(); it != widget_children.end(); it++) {
		if (widget == (*it))
			return true;
	}
	return false;
}

size_t Widget::list(const size_t indent, const bool visible_only) const
{
	if (visible_only && !visible())
		return 0;

	print(indent);
	size_t n = 1;
	for (Children::const_iterator it = widget_children.begin(); it != widget_children.end(); it++) {
		n += (*it)->list(indent + 1, visible_only);
	}
	return n;
}

void Widget::print(const size_t indent) const
{
	if (indent) {
		std::string marker;
		if (!widget_enabled) {
			marker.assign("^B- ");
		} else if (widget_focus) {
			marker.assign("^B* ");
		} else {
			marker.assign("  ");
		}
		if (widget_visible) {
			marker.append("^N");
		} else {
			marker.append("^D");
		}
		con_print << aux::pad_left(marker, indent*2) << label() << std::endl;
	}
}

const Palette *Widget::palette() const
{
	if (widget_palette) {
		return widget_palette;
	} else {
		return parent()->palette();
	}
}

const Font *Widget::font() const
{
	if (widget_font) {
		return widget_font;
	} else {
		return parent()->font();
	}
}

void Widget::lower()
{
	if (!parent())
		return;

	Children::iterator it = parent()->find_child(this);
	if (it != parent()->children().end()) {
		parent()->children().erase(it);
		parent()->children().push_front(this);
	}
}

void Widget::raise()
{
	if (!parent())
		return;

	Children::iterator it = parent()->find_child(this);
	if (it != parent()->children().end()) {
		parent()->children().erase(it);
		parent()->children().push_back(this);
	}
}

void Widget::set_focus()
{
	if (!parent()) {
		widget_focus = true;
		return;
	}

	for (Children::iterator it = parent()->children().begin(); it != parent()->children().end(); it++) {
		(*it)->widget_focus = false;
	}

	widget_focus = true;
}

void Widget::show()
{
	widget_visible = true;
}

void Widget::hide()
{
	widget_visible = false;
		
	if (parent() && focus()) {
		
		Widget *sibling =  next_sibling();
		
		while (sibling && (sibling != this) && !sibling->visible()) {
			sibling =  sibling->next_sibling();
		}
		if (sibling)
			sibling->set_focus();
	}
	/*
	if (parent() && focus()) {
		Widget::Children::reverse_iterator it = parent()->children().rbegin();

		while (it !=  parent()->children().rend()) {
			Widget *w = (*it);
			if (w != this && w->visible()) {
				widget_focus = false;
				w->widget_focus = true;
				it = parent()->children().rend();
			} else {
				it++;
			}
		}
	}
	*/
}


void Widget::set_visible(const bool visible)
{
	if (visible)
		show();
	else
		hide();
}

void Widget::enable()
{
	widget_enabled = true;
}

void Widget::disable()
{
	widget_enabled = false;
}

void Widget::set_enabled(const bool enabled)
{
	if (enabled)
		enable();
	else
		disable();
}

void Widget::set_border(const bool border)
{
	widget_border = border;
}


void Widget::set_background(const bool background)
{
	widget_background = background;
}

void Widget::set_label(const std::string & label)
{
	widget_label.assign(label);
	aux::to_label(widget_label);
}

void Widget::set_label(const char *label)
{
	if (label) {
		widget_label.assign(label);
		aux::to_label(widget_label);
	} else {
		widget_label.clear();
	}
}

void Widget::set_palette(const Palette *palette)
{
	widget_palette = palette;
}

void Widget::set_font(const Font *font)
{
	widget_font = font;
}

void Widget::set_geometry(const float x, const float y, const float w, const float h)
{
	widget_location.assign(x, y);
	widget_size.assign(w, h);
}

void Widget::set_geometry(const math::Vector2f &location, const math::Vector2f &size)
{
	widget_location.assign(location);
	widget_size.assign(size);
}

void Widget::set_location(const float x, const float y)
{
	widget_location.assign(x, y);
}

void Widget::set_location(const math::Vector2f &location)
{
	widget_location.assign(location);
}

void Widget::set_size(const float w, const float h)
{
	widget_size.assign(w, h);
}

void Widget::set_size(const math::Vector2f &size)
{
	widget_size.assign(size);
}

void Widget::set_width(const float w)
{
	widget_size[0] = w;
}

void Widget::set_height(const float h)
{
	widget_size[1] = h;
}

Widget *Widget::next_sibling() 
{
	if (!parent() || (parent()->children().size() < 2)) {
		return 0;
	}
	
	// find this widget in the parent's children
	Children::iterator it = parent()->children().begin(); 
	while (it != parent()->children().end() && ((*it) != this)) {
		it++;		
	}
		
	// assert this widget is a child of its parent
	assert (it != parent()->children().end());
	
	// next sibling
	it++;
	if (it == parent()->children().end()) {
		it = parent()->children().begin();
	}
	if ((*it) == this) {
		return 0;
	} else {
		return (*it);
	}
}

Widget::Children::iterator Widget::find_child(Widget *child)
{
	Children::iterator it;
	for (it = widget_children.begin(); it != widget_children.end(); it++) {
		if ((*it) == child)
			return it;
	}

	return it;
}

void Widget::add_child(Widget *child)
{
	Children::iterator it = find_child(child);
	if (it == widget_children.end()) {
		widget_children.push_back(child);
	}
}

void Widget::remove_child(Widget *child)
{
	Children::iterator it = find_child(child);
	if (it != widget_children.end()) {
		Widget *w = (*it);
		w->widget_parent = 0;
		delete(w);
		widget_children.erase(it);
	}
}

Widget *Widget::find_input_focus()
{
	if (!visible() || !widget_focus)
		return 0;

	for (Children::reverse_iterator rit = widget_children.rbegin(); rit != widget_children.rend(); ++rit) {
		Widget *w = (*rit);
		if (w->visible() && w->enabled() && w->widget_focus) {
			Widget *f = w->find_input_focus();
			if (f)
				return f;
		}
	}

	// no child with input focus
	return this;
}

Widget *Widget::find_visible_child(const Widget *widget)
{
	if (!visible())
		return 0;
	
	if (this == widget)
		return this;

	// search in reverse drawing order
	for (Children::reverse_iterator rit = widget_children.rbegin(); rit != widget_children.rend(); ++rit) {
		Widget *f = (*rit)->find_visible_child(widget);
		if (f) {
			return f;
		}
	}
	return 0;
}

Widget *Widget::find_mouse_focus(const math::Vector2f & pos)
{
	// this widget is not visible
	if (!visible() || !size().contains(pos))
		return 0;

	// reverse-iterate children
	for (Children::reverse_iterator rit = widget_children.rbegin(); rit != widget_children.rend(); ++rit) {
		Widget *w = (*rit);
		if (w->visible() && w->enabled()) {
			Widget *f = w->find_mouse_focus(pos - w->location());
			if (f)
				return f;
		}

	}

	// no child with mouse focus
	return this;
}

bool Widget::has_mouse_focus() const
{
	return (root()->mouse_focus() == this);
}

bool Widget::has_input_focus() const
{
	return (root()->input_focus() == this);
}

/* -- event distributors ------------------------------------------- */

bool Widget::event_emit(Widget *sender, const Event event, void *data)
// Unhandled events are sent to the parent widget
{
	if (disabled())
		return false;
	
	if (on_emit(sender, event, data)) {
		return true;
	} else if (parent()) {
		return (parent()->event_emit(sender, event, data));
	} else {
		return false;
	}
}


bool Widget::event_key(const bool pressed, const int key, const unsigned int modifier)
// Unhandled key events are sent to the parent widget
{
	bool handled = false;

	if (enabled()) {
		if (pressed) {
			handled = on_keypress(key, modifier);
		} else {
			handled = on_keyrelease(key, modifier);
		}
	}
	
	if (!handled && parent())
		handled = parent()->event_key(pressed, key, modifier);

	return handled;
}

bool Widget::event_mouse(const math::Vector2f &cursor)
{
	if (disabled())
		return false;
	
	math::Vector2f local_cursor = to_local_coords(cursor);
	bool handled = false;

	if (root()->mouse_focus() != this) {
		on_mouseover(local_cursor);
	}

	on_mousemove(local_cursor);
	return handled;
}

void Widget::event_draw()
{
	if (!visible())
		return;

	if (widget_background)
		draw_background();
	
	draw();

	for (Children::iterator it = widget_children.begin(); it != widget_children.end(); it++) {
		if ((*it)->visible())
			(*it)->event_draw();
	}
	
	if (widget_border)
		draw_border();
	
	if (debug())
		draw_debug();
}

void Widget::event_resize()
{
	resize();

	for (Children::iterator it = widget_children.begin(); it != widget_children.end(); it++) {
		(*it)->event_resize();
	}
}

/* -- event handlers ----------------------------------------------- */

void Widget::on_mouseover(const math::Vector2f &cursor)
{
	return;
}

void Widget::on_mousemove(const math::Vector2f &cursor)
{
	return;
}

bool Widget::on_keypress(const int key, const unsigned int modifier)
{
	return false;
}

bool Widget::on_keyrelease(const int key, const unsigned int modifier)
{
	return false;
}

bool Widget::on_emit(Widget *sender, const Event event, void *data)
{
	return false;
}

/* -- draw functions ----------------------------------------------- */

void Widget::draw_debug()
{
	Paint::set_color(1.0f, 0.0f, 1.0f, 0.5f);
	Paint::draw_border(global_location(), size());
}

void Widget::draw_background()
{
	//Paint::set_color(palette()->background());
	//Paint::draw_rectangle(global_location(), size());
	Paint::draw_material(global_location(), size(), "ui/background");
}

void Widget::draw_border()
{
	Paint::set_color(palette()->border());
	Paint::draw_border(global_location(), size());
}

void Widget::draw()
{
}

void Widget::resize()
{
}

}