/*
 * This program 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.
 *
 * This program 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 this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 */

/** \file
 * \ingroup edtransform
 */

#include <stdlib.h>

#include "MEM_guardedalloc.h"

#include "DNA_anim_types.h"

#include "BLI_math.h"
#include "BLI_string.h"

#include "BKE_context.h"
#include "BKE_nla.h"
#include "BKE_unit.h"

#include "ED_screen.h"

#include "UI_interface.h"
#include "UI_view2d.h"

#include "BLT_translation.h"

#include "transform.h"
#include "transform_convert.h"

#include "transform_mode.h"

/* -------------------------------------------------------------------- */
/** \name Transform (Animation Time Slide)
 * \{ */

static void headerTimeSlide(TransInfo *t, const float sval, char str[UI_MAX_DRAW_STR])
{
  char tvec[NUM_STR_REP_LEN * 3];

  if (hasNumInput(&t->num)) {
    outputNumInput(&(t->num), tvec, &t->scene->unit);
  }
  else {
    const float *range = t->custom.mode.data;
    float minx = range[0];
    float maxx = range[1];
    float cval = t->values_final[0];
    float val;

    val = 2.0f * (cval - sval) / (maxx - minx);
    CLAMP(val, -1.0f, 1.0f);

    BLI_snprintf(&tvec[0], NUM_STR_REP_LEN, "%.4f", val);
  }

  BLI_snprintf(str, UI_MAX_DRAW_STR, TIP_("TimeSlide: %s"), &tvec[0]);
}

static void applyTimeSlideValue(TransInfo *t, float sval, float cval)
{
  int i;
  const float *range = t->custom.mode.data;
  float minx = range[0];
  float maxx = range[1];

  /* set value for drawing black line */
  if (t->spacetype == SPACE_ACTION) {
    SpaceAction *saction = (SpaceAction *)t->area->spacedata.first;
    saction->timeslide = cval;
  }

  /* It doesn't matter whether we apply to t->data or
   * t->data2d, but t->data2d is more convenient. */
  FOREACH_TRANS_DATA_CONTAINER (t, tc) {
    TransData *td = tc->data;
    for (i = 0; i < tc->data_len; i++, td++) {
      /* it is assumed that td->extra is a pointer to the AnimData,
       * whose active action is where this keyframe comes from
       * (this is only valid when not in NLA)
       */
      AnimData *adt = (t->spacetype != SPACE_NLA) ? td->extra : NULL;

      /* only apply to data if in range */
      if ((sval > minx) && (sval < maxx)) {
        float cvalc = CLAMPIS(cval, minx, maxx);
        float ival = td->ival;
        float timefac;

        /* NLA mapping magic here works as follows:
         * - "ival" goes from strip time to global time
         * - calculation is performed into td->val in global time
         *   (since sval and min/max are all in global time)
         * - "td->val" then gets put back into strip time
         */
        if (adt) {
          /* strip to global */
          ival = BKE_nla_tweakedit_remap(adt, ival, NLATIME_CONVERT_MAP);
        }

        /* left half? */
        if (ival < sval) {
          timefac = (sval - ival) / (sval - minx);
          *(td->val) = cvalc - timefac * (cvalc - minx);
        }
        else {
          timefac = (ival - sval) / (maxx - sval);
          *(td->val) = cvalc + timefac * (maxx - cvalc);
        }

        if (adt) {
          /* global to strip */
          *(td->val) = BKE_nla_tweakedit_remap(adt, *(td->val), NLATIME_CONVERT_UNMAP);
        }
      }
    }
  }
}

static void applyTimeSlide(TransInfo *t, const int mval[2])
{
  View2D *v2d = (View2D *)t->view;
  float cval[2], sval[2];
  const float *range = t->custom.mode.data;
  float minx = range[0];
  float maxx = range[1];
  char str[UI_MAX_DRAW_STR];

  /* calculate mouse co-ordinates */
  UI_view2d_region_to_view(v2d, mval[0], mval[1], &cval[0], &cval[1]);
  UI_view2d_region_to_view(v2d, t->mouse.imval[0], t->mouse.imval[1], &sval[0], &sval[1]);

  /* t->values_final[0] stores cval[0], which is the current mouse-pointer location (in frames) */
  /* XXX Need to be able to repeat this. */
  /* t->values_final[0] = cval[0]; */ /* UNUSED (reset again later). */

  /* handle numeric-input stuff */
  t->vec[0] = 2.0f * (cval[0] - sval[0]) / (maxx - minx);
  applyNumInput(&t->num, &t->vec[0]);
  t->values_final[0] = (maxx - minx) * t->vec[0] / 2.0f + sval[0];

  headerTimeSlide(t, sval[0], str);
  applyTimeSlideValue(t, sval[0], t->values_final[0]);

  recalcData(t);

  ED_area_status_text(t->area, str);
}

void initTimeSlide(TransInfo *t)
{
  /* this tool is only really available in the Action Editor... */
  if (t->spacetype == SPACE_ACTION) {
    SpaceAction *saction = (SpaceAction *)t->area->spacedata.first;

    /* set flag for drawing stuff */
    saction->flag |= SACTION_MOVING;
  }
  else {
    t->state = TRANS_CANCEL;
  }

  t->mode = TFM_TIME_SLIDE;
  t->transform = applyTimeSlide;

  initMouseInputMode(t, &t->mouse, INPUT_NONE);

  {
    Scene *scene = t->scene;
    float *range;
    t->custom.mode.data = range = MEM_mallocN(sizeof(float[2]), "TimeSlide Min/Max");
    t->custom.mode.use_free = true;

    float min = 999999999.0f, max = -999999999.0f;
    int i;
    FOREACH_TRANS_DATA_CONTAINER (t, tc) {
      TransData *td = tc->data;
      for (i = 0; i < tc->data_len; i++, td++) {
        AnimData *adt = (t->spacetype != SPACE_NLA) ? td->extra : NULL;
        float val = *(td->val);

        /* strip/action time to global (mapped) time */
        if (adt) {
          val = BKE_nla_tweakedit_remap(adt, val, NLATIME_CONVERT_MAP);
        }

        if (min > val) {
          min = val;
        }
        if (max < val) {
          max = val;
        }
      }
    }

    if (min == max) {
      /* just use the current frame ranges */
      min = (float)PSFRA;
      max = (float)PEFRA;
    }

    range[0] = min;
    range[1] = max;
  }

  /* num-input has max of (n-1) */
  t->idx_max = 0;
  t->num.flag = 0;
  t->num.idx_max = t->idx_max;

  /* initialize snap like for everything else */
  t->snap[0] = t->snap[1] = 1.0f;

  copy_v3_fl(t->num.val_inc, t->snap[0]);
  t->num.unit_sys = t->scene->unit.system;
  /* No time unit supporting frames currently... */
  t->num.unit_type[0] = B_UNIT_NONE;
}

/** \} */