/*

 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

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

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

#include "hb.h"

#include "hb-jdk.h"

#ifdef MACOSX

#include "hb-coretext.h"

#endif

#include <stdlib.h>

#if defined(__GNUC__) &&  __GNUC__ >= 4

#define HB_UNUSED       __attribute__((unused))

#else

#define HB_UNUSED

#endif

static hb_bool_t

		 void *font_data,

		 hb_codepoint_t unicode,

		 hb_codepoint_t variation_selector,

		 hb_codepoint_t *glyph,

		 void *user_data HB_UNUSED)

{

    JDKFontInfo *jdkFontInfo = (JDKFontInfo*)font_data;

    JNIEnv* env = jdkFontInfo->env;

    jobject font2D = jdkFontInfo->font2D;

    if (env->ExceptionOccurred())

    {

        env->ExceptionClear();

    }

    if ((int)*glyph < 0) {

        *glyph = 0;

    }

    return (*glyph != 0);

}

static hb_position_t

hb_jdk_get_glyph_h_advance (hb_font_t *font HB_UNUSED,

			   void *font_data,

			   hb_codepoint_t glyph,

			   void *user_data HB_UNUSED)

{

    float fadv = 0.0f;

    if ((glyph & 0xfffe) == 0xfffe) {

        return 0; // JDK uses this glyph code.

    }

    JDKFontInfo *jdkFontInfo = (JDKFontInfo*)font_data;

    JNIEnv* env = jdkFontInfo->env;

    jobject fontStrike = jdkFontInfo->fontStrike;

    jobject pt = env->CallObjectMethod(fontStrike,

                                       sunFontIDs.getGlyphMetricsMID, glyph);

    if (pt == NULL) {

        return 0;

    }

    fadv = env->GetFloatField(pt, sunFontIDs.xFID);

    fadv *= jdkFontInfo->devScale;

    env->DeleteLocalRef(pt);

    return HBFloatToFixed(fadv);

}

static hb_position_t

hb_jdk_get_glyph_v_advance (hb_font_t *font HB_UNUSED,

			   void *font_data,

			   hb_codepoint_t glyph,

			   void *user_data HB_UNUSED)

{

    float fadv = 0.0f;

    if ((glyph & 0xfffe) == 0xfffe) {

        return 0; // JDK uses this glyph code.

    }

    JDKFontInfo *jdkFontInfo = (JDKFontInfo*)font_data;

    JNIEnv* env = jdkFontInfo->env;

    jobject fontStrike = jdkFontInfo->fontStrike;

    jobject pt = env->CallObjectMethod(fontStrike,

                                       sunFontIDs.getGlyphMetricsMID, glyph);

    if (pt == NULL) {

        return 0;

    }

    fadv = env->GetFloatField(pt, sunFontIDs.yFID);

    env->DeleteLocalRef(pt);

    return HBFloatToFixed(fadv);

}

static hb_bool_t

hb_jdk_get_glyph_h_origin (hb_font_t *font HB_UNUSED,

			  void *font_data HB_UNUSED,

			  hb_codepoint_t glyph HB_UNUSED,

			  hb_position_t *x HB_UNUSED,

			  hb_position_t *y HB_UNUSED,

			  void *user_data HB_UNUSED)

{

  /* We always work in the horizontal coordinates. */

  return true;

}

static hb_bool_t

hb_jdk_get_glyph_v_origin (hb_font_t *font HB_UNUSED,

			  void *font_data,

			  hb_codepoint_t glyph,

			  hb_position_t *x,

			  hb_position_t *y,

			  void *user_data HB_UNUSED)

{

  return false;

}

static hb_position_t

hb_jdk_get_glyph_h_kerning (hb_font_t *font,

			   void *font_data,

			   hb_codepoint_t lejdk_glyph,

			   hb_codepoint_t right_glyph,

			   void *user_data HB_UNUSED)

{

  /* Not implemented. This seems to be in the HB API

   * as a way to fall back to Freetype's kerning support

   * which could be based on some on-the fly glyph analysis.

   * But more likely it reads the kern table. That is easy

   * enough code to add if we find a need to fall back

   * to that instead of using gpos. It seems like if

   * there is a gpos table at all, the practice is to

   * use that and ignore kern, no matter that gpos does

   * not implement the kern feature.

   */

  return 0;

}

static hb_position_t

hb_jdk_get_glyph_v_kerning (hb_font_t *font HB_UNUSED,

			   void *font_data HB_UNUSED,

			   hb_codepoint_t top_glyph HB_UNUSED,

			   hb_codepoint_t bottom_glyph HB_UNUSED,

			   void *user_data HB_UNUSED)

{

  /* OpenType doesn't have vertical-kerning other than GPOS. */

  return 0;

}

static hb_bool_t

hb_jdk_get_glyph_extents (hb_font_t *font HB_UNUSED,

			 void *font_data,

			 hb_codepoint_t glyph,

			 hb_glyph_extents_t *extents,

			 void *user_data HB_UNUSED)

{

  /* TODO */

  return false;

}

static hb_bool_t

hb_jdk_get_glyph_contour_point (hb_font_t *font HB_UNUSED,

			       void *font_data,

			       hb_codepoint_t glyph,

			       unsigned int point_index,

			       hb_position_t *x,

			       hb_position_t *y,

			       void *user_data HB_UNUSED)

{

    if ((glyph & 0xfffe) == 0xfffe) {

        *x = 0; *y = 0;

        return true;

    }

    JDKFontInfo *jdkFontInfo = (JDKFontInfo*)font_data;

    JNIEnv* env = jdkFontInfo->env;

    jobject fontStrike = jdkFontInfo->fontStrike;

    jobject pt = env->CallObjectMethod(fontStrike,

                                       sunFontIDs.getGlyphPointMID,

                                       glyph, point_index);

    if (pt == NULL) {

        *x = 0; *y = 0;

        return true;

    }

    *x = HBFloatToFixed(env->GetFloatField(pt, sunFontIDs.xFID));

    *y = HBFloatToFixed(env->GetFloatField(pt, sunFontIDs.yFID));

    env->DeleteLocalRef(pt);

  return true;

}

static hb_bool_t

hb_jdk_get_glyph_name (hb_font_t *font HB_UNUSED,

		      void *font_data,

		      hb_codepoint_t glyph,

		      char *name, unsigned int size,

		      void *user_data HB_UNUSED)

{

  return false;

}

static hb_bool_t

hb_jdk_get_glyph_from_name (hb_font_t *font HB_UNUSED,

			   void *font_data,

			   const char *name, int len,

			   hb_codepoint_t *glyph,

			   void *user_data HB_UNUSED)

{

  return false;

}

// remind : can we initialise this from the code we call

// from the class static method in Java to make it

// completely thread safe.

static hb_font_funcs_t *

_hb_jdk_get_font_funcs (void)

{

  static hb_font_funcs_t *jdk_ffuncs = NULL;

  hb_font_funcs_t *ff;

  if (!jdk_ffuncs) {

      ff = hb_font_funcs_create();

      hb_font_funcs_set_glyph_h_advance_func(ff,

                    hb_jdk_get_glyph_h_advance, NULL, NULL);

      hb_font_funcs_set_glyph_v_advance_func(ff,

                    hb_jdk_get_glyph_v_advance, NULL, NULL);

      hb_font_funcs_set_glyph_h_origin_func(ff,

                    hb_jdk_get_glyph_h_origin, NULL, NULL);

      hb_font_funcs_set_glyph_v_origin_func(ff,

                    hb_jdk_get_glyph_v_origin, NULL, NULL);

      hb_font_funcs_set_glyph_h_kerning_func(ff,

                    hb_jdk_get_glyph_h_kerning, NULL, NULL);

      hb_font_funcs_set_glyph_v_kerning_func(ff,

                    hb_jdk_get_glyph_v_kerning, NULL, NULL);

      hb_font_funcs_set_glyph_extents_func(ff,

                    hb_jdk_get_glyph_extents, NULL, NULL);

      hb_font_funcs_set_glyph_contour_point_func(ff,

                    hb_jdk_get_glyph_contour_point, NULL, NULL);

      hb_font_funcs_set_glyph_name_func(ff,

                    hb_jdk_get_glyph_name, NULL, NULL);

      hb_font_funcs_set_glyph_from_name_func(ff,

                    hb_jdk_get_glyph_from_name, NULL, NULL);

      hb_font_funcs_make_immutable(ff); // done setting functions.

      jdk_ffuncs = ff;

  }

  return jdk_ffuncs;

}

static void _do_nothing(void) {

}

static void _free_nothing(void*) {

}

static hb_blob_t *

reference_table(hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data) {

  JDKFontInfo *jdkFontInfo = (JDKFontInfo*)user_data;

  JNIEnv* env = jdkFontInfo->env;

  jobject font2D = jdkFontInfo->font2D;

  jsize length = 0;

  void* buffer = NULL;

  int cacheIdx = 0;

  // HB_TAG_NONE is 0 and is used to get the whole font file.

  // It is not expected to be needed for JDK.

  if (tag == 0 || jdkFontInfo->layoutTables == NULL) {

      return NULL;

  }

  for (cacheIdx=0; cacheIdx<LAYOUTCACHE_ENTRIES; cacheIdx++) {

    if (tag == jdkFontInfo->layoutTables->entries[cacheIdx].tag) break;

  }

  if (cacheIdx < LAYOUTCACHE_ENTRIES) { // if found

      if (jdkFontInfo->layoutTables->entries[cacheIdx].len != -1) {

          length = jdkFontInfo->layoutTables->entries[cacheIdx].len;

          buffer = (void*)jdkFontInfo->layoutTables->entries[cacheIdx].ptr;

      }

  }

  if (buffer == NULL) {

      jbyteArray tableBytes = (jbyteArray)

         env->CallObjectMethod(font2D, sunFontIDs.getTableBytesMID, tag);

      if (tableBytes == NULL) {

          return NULL;

      }

      length = env->GetArrayLength(tableBytes);

      buffer = calloc(length, sizeof(jbyte));

      env->GetByteArrayRegion(tableBytes, 0, length, (jbyte*)buffer);

     if (cacheIdx >= LAYOUTCACHE_ENTRIES) { // not a cacheable table

          return hb_blob_create((const char *)buffer, length,

                                 HB_MEMORY_MODE_WRITABLE,

                                 buffer, free);

      } else {

        jdkFontInfo->layoutTables->entries[cacheIdx].len = length;

        jdkFontInfo->layoutTables->entries[cacheIdx].ptr = buffer;

      }

  }

  return hb_blob_create((const char *)buffer, length,

                         HB_MEMORY_MODE_READONLY,

                         NULL, _free_nothing);

}

hb_face_t*

hb_jdk_face_create(JDKFontInfo *jdkFontInfo,

                   hb_destroy_func_t destroy) {

    hb_face_t *face =

         hb_face_create_for_tables(reference_table, jdkFontInfo, destroy);

    return face;

}

static hb_font_t* _hb_jdk_font_create(JDKFontInfo *jdkFontInfo,

                                      hb_destroy_func_t destroy) {

    hb_font_t *font;

    hb_face_t *face;

    face = hb_jdk_face_create(jdkFontInfo, destroy);

    font = hb_font_create(face);

    hb_face_destroy (face);

    hb_font_set_funcs (font,

                       _hb_jdk_get_font_funcs (),

                       jdkFontInfo, (hb_destroy_func_t) _do_nothing);

    hb_font_set_scale (font,

                      HBFloatToFixed(jdkFontInfo->ptSize*jdkFontInfo->devScale),

                      HBFloatToFixed(jdkFontInfo->ptSize*jdkFontInfo->devScale));

  return font;

}

#ifdef MACOSX

static hb_font_t* _hb_jdk_ct_font_create(JDKFontInfo *jdkFontInfo) {

    hb_font_t *font = NULL;

    hb_face_t *face = NULL;

    if (jdkFontInfo->nativeFont == 0) {

        return NULL;

    }

    face = hb_coretext_face_create((CGFontRef)(jdkFontInfo->nativeFont));

    font = hb_font_create(face);

    hb_face_destroy(face);

    hb_font_set_scale(font,

                     HBFloatToFixed(jdkFontInfo->ptSize),

                     HBFloatToFixed(jdkFontInfo->ptSize));

    return font;

}

#endif

hb_font_t* hb_jdk_font_create(JDKFontInfo *jdkFontInfo,

                             hb_destroy_func_t destroy) {

   hb_font_t* font = NULL;

#ifdef MACOSX

     if (jdkFontInfo->aat) {

         font = _hb_jdk_ct_font_create(jdkFontInfo);

     }

#endif

    if (font == NULL) {

        font = _hb_jdk_font_create(jdkFontInfo, destroy);

    }

    return font;

}