/**
 * @file
 * @section AUTHORS
 *
 *  Authors:
 *       Eamon Walsh <ewalsh@tycho.nsa.gov>
 *
 * @section LICENSE
 *
 * This file is in the public domain.
 *
 * @section DESCRIPTION
 *
 * This is the code that handles incoming libvchan events from linpicker-track.
 * This code shoud be robust against bad behavior on the  other side, as
 * we don't trust the guest that is running linpicker-track.
 */

#include <sys/types.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include "fd.h"
#include "comm.h"
#include "view.h"
#include "buffer.h"
#include "client.h"
#include "display.h"

static void
comm_do_update(struct client *c, struct buffer *b, struct view *v,
	       struct lin_message *m)
{
    /* Set view position */
    if (m->flags & LINPICKER_FLAG_POSITION) {
	DFBRectangle bpos = { .x = m->x, .y = m->y, .w = m->w, .h = m->h };
	DFBRectangle spos;

	/* Clip view rectangle to buffer */
	if (bpos.x < 0) {
	    bpos.w += bpos.x;
	    bpos.x = 0;
	}
	if (bpos.x + bpos.w > b->desc.width)
	    bpos.w = b->desc.width - bpos.x;
	if (bpos.w < 0)
	    bpos.w = 0;

	if (bpos.y < 0) {
	    bpos.h += bpos.y;
	    bpos.y = 0;
	}
	if (bpos.y + bpos.h > b->desc.height)
	    bpos.h = b->desc.height - bpos.y;
	if (bpos.h < 0)
	    bpos.h = 0;

	spos = bpos;
	spos.x += b->xoff;
	spos.y += b->yoff;

	view_set_viewport(v, &bpos, &spos, m->w != v->bpos.w || m->h != v->bpos.h);
    }

    /* Set view stacking */
    if (m->flags & LINPICKER_FLAG_TOPMOST)
	view_stack(v, VIEW_STACK_TOP, NULL);
    else if (m->flags & LINPICKER_FLAG_BOTMOST)
	view_stack(v, VIEW_STACK_BOTTOM, NULL);
    else if (m->flags & LINPICKER_FLAG_SIBLING) {
	struct view *s = view_lookup(c, m->sibling);
	if (s && s != v)
	    view_stack(v, VIEW_STACK_ABOVE, s);
    }

    /* Set view visibility */
    if (m->flags & LINPICKER_FLAG_SHOWN)
	v->mapped = 1;
    else if (m->flags & LINPICKER_FLAG_HIDDEN)
	v->mapped = 0;

    view_show(v);
}

static void
comm_create(struct client *c, struct buffer *b, struct lin_message *m)
{
    struct view *v = view_lookup(c, m->view);
    if (v)
	FD_LOG(1, "Warning: view %x already exists.\n", m->view);
    else {
	v = view_new(c, b, m->view, VIEW_FLAGS_CLIENT);
	if (!v) {
	    FD_LOG(0, "Failed to create view!\n");
	    return;
	}
	v->mapped = 0;
    }

    comm_do_update(c, b, v, m);
}

static void
comm_update(struct client *c, struct buffer *b, struct lin_message *m)
{
    struct view *v = view_lookup(c, m->view);
    if (!v) {
	FD_LOG(1, "Warning: view %x does not exist.\n", m->view);
	return;
    }

    comm_do_update(c, b, v, m);
}

static void
comm_destroy(struct client *c, struct buffer *b, struct lin_message *m)
{
    struct view *v = view_lookup(c, m->view);
    if (v)
	view_remove(v);
}

static void
comm_destroy_all(struct client *c, struct buffer *b)
{
    struct view *v;

top:
    TAILQ_FOREACH(v, &b->views, buffer_next) {
	if (v->flags & VIEW_FLAGS_THUMBNAIL)
	    continue;
	if (v->flags & VIEW_FLAGS_BACKGROUND)
	    continue;

	view_remove(v);
	break;
    }

    if (v)
	goto top;
}

void
comm_process(struct client *c, struct buffer *b, struct lin_message *m)
{
    switch (m->type) {
    case LINPICKER_RESET:
	comm_destroy_all(c, b);
	break;
    case LINPICKER_CREATE:
	comm_create(c, b, m);
	break;
    case LINPICKER_UPDATE:
	comm_update(c, b, m);
	break;
    case LINPICKER_DESTROY:
	comm_destroy(c, b, m);
	break;
    default:
	break;
    }
}