/**********************************************************************

 *

 * PostGIS - Spatial Types for PostgreSQL

 * http://postgis.net

 *

 * PostGIS is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, either version 2 of the License, or

 * (at your option) any later version.

 *

 * PostGIS is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with PostGIS.  If not, see <http://www.gnu.org/licenses/>.

 *

 **********************************************************************

 *

 * Copyright 2001-2006 Refractions Research Inc.

 *

 **********************************************************************/

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "liblwgeom_internal.h"

void

lwmline_release(LWMLINE *lwmline)

{

  lwgeom_release(lwmline_as_lwgeom(lwmline));

}

LWMLINE *

lwmline_construct_empty(int32_t srid, char hasz, char hasm)

{

  LWMLINE *ret = (LWMLINE*)lwcollection_construct_empty(MULTILINETYPE, srid, hasz, hasm);

  return ret;

}

LWMLINE* lwmline_add_lwline(LWMLINE *mobj, const LWLINE *obj)

{

  return (LWMLINE*)lwcollection_add_lwgeom((LWCOLLECTION*)mobj, (LWGEOM*)obj);

}

/**

* Re-write the measure ordinate (or add one, if it isn't already there) interpolating

* the measure between the supplied start and end values.

*/

LWMLINE*

lwmline_measured_from_lwmline(const LWMLINE *lwmline, double m_start, double m_end)

{

  uint32_t i = 0;

  int hasm = 0, hasz = 0;

  double length = 0.0, length_so_far = 0.0;

  double m_range = m_end - m_start;

  LWGEOM **geoms = NULL;

  if ( lwmline->type != MULTILINETYPE )

  {

    lwerror("lwmline_measured_from_lmwline: only multiline types supported");

    return NULL;

  }

  hasz = FLAGS_GET_Z(lwmline->flags);

  hasm = 1;

  /* Calculate the total length of the mline */

  for ( i = 0; i < lwmline->ngeoms; i++ )

  {

    LWLINE *lwline = (LWLINE*)lwmline->geoms[i];

    if ( lwline->points && lwline->points->npoints > 1 )

    {

      length += ptarray_length_2d(lwline->points);

    }

  }

  if ( lwgeom_is_empty((LWGEOM*)lwmline) )

  {

    return (LWMLINE*)lwcollection_construct_empty(MULTILINETYPE, lwmline->srid, hasz, hasm);

  }

  geoms = lwalloc(sizeof(LWGEOM*) * lwmline->ngeoms);

  for ( i = 0; i < lwmline->ngeoms; i++ )

  {

    double sub_m_start, sub_m_end;

    double sub_length = 0.0;

    LWLINE *lwline = (LWLINE*)lwmline->geoms[i];

    if ( lwline->points && lwline->points->npoints > 1 )

    {

      sub_length = ptarray_length_2d(lwline->points);

    }

    sub_m_start = (m_start + m_range * length_so_far / length);

    sub_m_end = (m_start + m_range * (length_so_far + sub_length) / length);

    geoms[i] = (LWGEOM*)lwline_measured_from_lwline(lwline, sub_m_start, sub_m_end);

    length_so_far += sub_length;

  }

  return (LWMLINE*)lwcollection_construct(lwmline->type, lwmline->srid, NULL, lwmline->ngeoms, geoms);

}

void lwmline_free(LWMLINE *mline)

{

  if (!mline)

    return;

  if (mline->bbox)

    lwfree(mline->bbox);

  if (mline->geoms)

  {

    for (uint32_t i = 0; i < mline->ngeoms; i++)

      if (mline->geoms[i])

        lwline_free(mline->geoms[i]);

    lwfree(mline->geoms);

  }

  lwfree(mline);

}