/*

 * Copyright © 2012  Google, Inc.

 *

 *  This is part of HarfBuzz, a text shaping library.

 *

 * Permission is hereby granted, without written agreement and without

 * license or royalty fees, to use, copy, modify, and distribute this

 * software and its documentation for any purpose, provided that the

 * above copyright notice and the following two paragraphs appear in

 * all copies of this software.

 *

 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR

 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES

 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN

 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH

 * DAMAGE.

 *

 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,

 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND

 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS

 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO

 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

 *

 * Google Author(s): Behdad Esfahbod

 */

#include "hb.hh"

#include "hb-shape-plan.hh"

#include "hb-shaper.hh"

#include "hb-font.hh"

#include "hb-buffer.hh"

#ifndef HB_NO_SHAPER

/**

 * SECTION:hb-shape-plan

 * @title: hb-shape-plan

 * @short_description: Object representing a shaping plan

 * @include: hb.h

 *

 * Shape plans are an internal mechanism. Each plan contains state

 * describing how HarfBuzz will shape a particular text segment, based on

 * the combination of segment properties and the capabilities in the

 * font face in use.

 *

 * Shape plans are not used for shaping directly, but can be queried to

 * access certain information about how shaping will perform, given a set

 * of specific input parameters (script, language, direction, features,

 * etc.).

 *

 * Most client programs will not need to deal with shape plans directly.

 **/

/*

 * hb_shape_plan_key_t

 */

bool

hb_shape_plan_key_t::init (bool                           copy,

         hb_face_t                     *face,

         const hb_segment_properties_t *props,

         const hb_feature_t            *user_features,

         unsigned int                   num_user_features,

         const int                     *coords,

         unsigned int                   num_coords,

         const char * const            *shaper_list)

{

  hb_feature_t *features = nullptr;

  if (copy && num_user_features && !(features = (hb_feature_t *) hb_calloc (num_user_features, sizeof (hb_feature_t))))

    goto bail;

  this->props = *props;

  this->num_user_features = num_user_features;

  this->user_features = copy ? features : user_features;

  if (copy && num_user_features)

  {

    hb_memcpy (features, user_features, num_user_features * sizeof (hb_feature_t));

    /* Make start/end uniform to easier catch bugs. */

    for (unsigned int i = 0; i < num_user_features; i++)

    {

      if (features[0].start != HB_FEATURE_GLOBAL_START)

  features[0].start = 1;

      if (features[0].end   != HB_FEATURE_GLOBAL_END)

  features[0].end   = 2;

    }

  }

  this->shaper_func = nullptr;

  this->shaper_name = nullptr;

#ifndef HB_NO_OT_SHAPE

  this->ot.init (face, coords, num_coords);

#endif

  /*

   * Choose shaper.

   */

#define HB_SHAPER_PLAN(shaper) \

  HB_STMT_START { \

    if (face->data.shaper) \

    { \

      this->shaper_func = _hb_##shaper##_shape; \

      this->shaper_name = #shaper; \

      return true; \

    } \

  } HB_STMT_END

  if (unlikely (shaper_list))

  {

    for (; *shaper_list; shaper_list++)

      if (false)

  ;

#define HB_SHAPER_IMPLEMENT(shaper) \

      else if (0 == strcmp (*shaper_list, #shaper)) \

  HB_SHAPER_PLAN (shaper);

#include "hb-shaper-list.hh"

#undef HB_SHAPER_IMPLEMENT

  }

  else

  {

    const HB_UNUSED hb_shaper_entry_t *shapers = _hb_shapers_get ();

    for (unsigned int i = 0; i < HB_SHAPERS_COUNT; i++)

      if (false)

  ;

#define HB_SHAPER_IMPLEMENT(shaper) \

      else if (shapers[i].func == _hb_##shaper##_shape) \

  HB_SHAPER_PLAN (shaper);

#include "hb-shaper-list.hh"

#undef HB_SHAPER_IMPLEMENT

  }

#undef HB_SHAPER_PLAN

bail:

  ::hb_free (features);

  return false;

}

bool

hb_shape_plan_key_t::user_features_match (const hb_shape_plan_key_t *other)

{

  if (this->num_user_features != other->num_user_features)

    return false;

  for (unsigned int i = 0; i < num_user_features; i++)

  {

    if (this->user_features[i].tag   != other->user_features[i].tag   ||

  this->user_features[i].value != other->user_features[i].value ||

  (this->user_features[i].start == HB_FEATURE_GLOBAL_START &&

   this->user_features[i].end   == HB_FEATURE_GLOBAL_END) !=

  (other->user_features[i].start == HB_FEATURE_GLOBAL_START &&

   other->user_features[i].end   == HB_FEATURE_GLOBAL_END))

      return false;

  }

  return true;

}

bool

hb_shape_plan_key_t::equal (const hb_shape_plan_key_t *other)

{

  return hb_segment_properties_equal (&this->props, &other->props) &&

   this->user_features_match (other) &&

#ifndef HB_NO_OT_SHAPE

   this->ot.equal (&other->ot) &&

#endif

   this->shaper_func == other->shaper_func;

}

/*

 * hb_shape_plan_t

 */

/**

 * hb_shape_plan_create:

 * @face: #hb_face_t to use

 * @props: The #hb_segment_properties_t of the segment

 * @user_features: (array length=num_user_features): The list of user-selected features

 * @num_user_features: The number of user-selected features

 * @shaper_list: (array zero-terminated=1): List of shapers to try

 *

 * Constructs a shaping plan for a combination of @face, @user_features, @props,

 * and @shaper_list.

 *

 * Return value: (transfer full): The shaping plan

 *

 * Since: 0.9.7

 **/

hb_shape_plan_t *

hb_shape_plan_create (hb_face_t                     *face,

          const hb_segment_properties_t *props,

          const hb_feature_t            *user_features,

          unsigned int                   num_user_features,

          const char * const            *shaper_list)

{

  return hb_shape_plan_create2 (face, props,

        user_features, num_user_features,

        nullptr, 0,

        shaper_list);

}

/**

 * hb_shape_plan_create2:

 * @face: #hb_face_t to use

 * @props: The #hb_segment_properties_t of the segment

 * @user_features: (array length=num_user_features): The list of user-selected features

 * @num_user_features: The number of user-selected features

 * @coords: (array length=num_coords): The list of variation-space coordinates

 * @num_coords: The number of variation-space coordinates

 * @shaper_list: (array zero-terminated=1): List of shapers to try

 *

 * The variable-font version of #hb_shape_plan_create.

 * Constructs a shaping plan for a combination of @face, @user_features, @props,

 * and @shaper_list, plus the variation-space coordinates @coords.

 *

 * Return value: (transfer full): The shaping plan

 *

 * Since: 1.4.0

 **/

hb_shape_plan_t *

hb_shape_plan_create2 (hb_face_t                     *face,

           const hb_segment_properties_t *props,

           const hb_feature_t            *user_features,

           unsigned int                   num_user_features,

           const int                     *coords,

           unsigned int                   num_coords,

           const char * const            *shaper_list)

{

  DEBUG_MSG_FUNC (SHAPE_PLAN, nullptr,

      "face=%p num_features=%u num_coords=%u shaper_list=%p",

      face,

      num_user_features,

      num_coords,

      shaper_list);

  if (unlikely (!HB_DIRECTION_IS_VALID (props->direction)))

    return hb_shape_plan_get_empty ();

  hb_shape_plan_t *shape_plan;

  if (unlikely (!props))

    goto bail;

  if (!(shape_plan = hb_object_create<hb_shape_plan_t> ()))

    goto bail;

  if (unlikely (!face))

    face = hb_face_get_empty ();

  hb_face_make_immutable (face);

  shape_plan->face_unsafe = face;

  if (unlikely (!shape_plan->key.init (true,

               face,

               props,

               user_features,

               num_user_features,

               coords,

               num_coords,

               shaper_list)))

    goto bail2;

#ifndef HB_NO_OT_SHAPE

  if (unlikely (!shape_plan->ot.init0 (face, &shape_plan->key)))

    goto bail3;

#endif

  return shape_plan;

#ifndef HB_NO_OT_SHAPE

bail3:

#endif

  shape_plan->key.fini ();

bail2:

  hb_free (shape_plan);

bail:

  return hb_shape_plan_get_empty ();

}

/**

 * hb_shape_plan_get_empty:

 *

 * Fetches the singleton empty shaping plan.

 *

 * Return value: (transfer full): The empty shaping plan

 *

 * Since: 0.9.7

 **/

hb_shape_plan_t *

hb_shape_plan_get_empty ()

{

  return const_cast<hb_shape_plan_t *> (&Null (hb_shape_plan_t));

}

/**

 * hb_shape_plan_reference: (skip)

 * @shape_plan: A shaping plan

 *

 * Increases the reference count on the given shaping plan.

 *

 * Return value: (transfer full): @shape_plan

 *

 * Since: 0.9.7

 **/

hb_shape_plan_t *

hb_shape_plan_reference (hb_shape_plan_t *shape_plan)

{

  return hb_object_reference (shape_plan);

}

/**

 * hb_shape_plan_destroy: (skip)

 * @shape_plan: A shaping plan

 *

 * Decreases the reference count on the given shaping plan. When the

 * reference count reaches zero, the shaping plan is destroyed,

 * freeing all memory.

 *

 * Since: 0.9.7

 **/

void

hb_shape_plan_destroy (hb_shape_plan_t *shape_plan)

{

  if (!hb_object_destroy (shape_plan)) return;

  hb_free (shape_plan);

}

/**

 * hb_shape_plan_set_user_data: (skip)

 * @shape_plan: A shaping plan

 * @key: The user-data key to set

 * @data: A pointer to the user data

 * @destroy: (nullable): A callback to call when @data is not needed anymore

 * @replace: Whether to replace an existing data with the same key

 *

 * Attaches a user-data key/data pair to the given shaping plan.

 *

 * Return value: `true` if success, `false` otherwise.

 *

 * Since: 0.9.7

 **/

hb_bool_t

hb_shape_plan_set_user_data (hb_shape_plan_t    *shape_plan,

           hb_user_data_key_t *key,

           void *              data,

           hb_destroy_func_t   destroy,

           hb_bool_t           replace)

{

  return hb_object_set_user_data (shape_plan, key, data, destroy, replace);

}

/**

 * hb_shape_plan_get_user_data: (skip)

 * @shape_plan: A shaping plan

 * @key: The user-data key to query

 *

 * Fetches the user data associated with the specified key,

 * attached to the specified shaping plan.

 *

 * Return value: (transfer none): A pointer to the user data

 *

 * Since: 0.9.7

 **/

void *

hb_shape_plan_get_user_data (const hb_shape_plan_t *shape_plan,

           hb_user_data_key_t    *key)

{

  return hb_object_get_user_data (shape_plan, key);

}

/**

 * hb_shape_plan_get_shaper:

 * @shape_plan: A shaping plan

 *

 * Fetches the shaper from a given shaping plan.

 *

 * Return value: (transfer none): The shaper

 *

 * Since: 0.9.7

 **/

const char *

hb_shape_plan_get_shaper (hb_shape_plan_t *shape_plan)

{

  return shape_plan->key.shaper_name;

}

static bool

_hb_shape_plan_execute_internal (hb_shape_plan_t    *shape_plan,

         hb_font_t          *font,

         hb_buffer_t        *buffer,

         const hb_feature_t *features,

         unsigned int        num_features)

{

  DEBUG_MSG_FUNC (SHAPE_PLAN, shape_plan,

      "num_features=%u shaper_func=%p, shaper_name=%s",

      num_features,

      shape_plan->key.shaper_func,

      shape_plan->key.shaper_name);

  if (unlikely (!buffer->len))

    return true;

  assert (!hb_object_is_immutable (buffer));

  buffer->assert_unicode ();

  if (unlikely (!hb_object_is_valid (shape_plan)))

    return false;

  assert (shape_plan->face_unsafe == font->face);

  assert (hb_segment_properties_equal (&shape_plan->key.props, &buffer->props));

#define HB_SHAPER_EXECUTE(shaper) \

  HB_STMT_START { \

    return font->data.shaper && \

     _hb_##shaper##_shape (shape_plan, font, buffer, features, num_features); \

  } HB_STMT_END

  if (false)

    ;

#define HB_SHAPER_IMPLEMENT(shaper) \

  else if (shape_plan->key.shaper_func == _hb_##shaper##_shape) \

    HB_SHAPER_EXECUTE (shaper);

#include "hb-shaper-list.hh"

#undef HB_SHAPER_IMPLEMENT

#undef HB_SHAPER_EXECUTE

  return false;

}

/**

 * hb_shape_plan_execute:

 * @shape_plan: A shaping plan

 * @font: The #hb_font_t to use

 * @buffer: The #hb_buffer_t to work upon

 * @features: (array length=num_features): Features to enable

 * @num_features: The number of features to enable

 *

 * Executes the given shaping plan on the specified buffer, using

 * the given @font and @features.

 *

 * Return value: `true` if success, `false` otherwise.

 *

 * Since: 0.9.7

 **/

hb_bool_t

hb_shape_plan_execute (hb_shape_plan_t    *shape_plan,

           hb_font_t          *font,

           hb_buffer_t        *buffer,

           const hb_feature_t *features,

           unsigned int        num_features)

{

  bool ret = _hb_shape_plan_execute_internal (shape_plan, font, buffer,

                features, num_features);

  if (ret && buffer->content_type == HB_BUFFER_CONTENT_TYPE_UNICODE)

    buffer->content_type = HB_BUFFER_CONTENT_TYPE_GLYPHS;

  return ret;

}

/*

 * Caching

 */

/**

 * hb_shape_plan_create_cached:

 * @face: #hb_face_t to use

 * @props: The #hb_segment_properties_t of the segment

 * @user_features: (array length=num_user_features): The list of user-selected features

 * @num_user_features: The number of user-selected features

 * @shaper_list: (array zero-terminated=1): List of shapers to try

 *

 * Creates a cached shaping plan suitable for reuse, for a combination

 * of @face, @user_features, @props, and @shaper_list.

 *

 * Return value: (transfer full): The shaping plan

 *

 * Since: 0.9.7

 **/

hb_shape_plan_t *

hb_shape_plan_create_cached (hb_face_t                     *face,

           const hb_segment_properties_t *props,

           const hb_feature_t            *user_features,

           unsigned int                   num_user_features,

           const char * const            *shaper_list)

{

  return hb_shape_plan_create_cached2 (face, props,

               user_features, num_user_features,

               nullptr, 0,

               shaper_list);

}

/**

 * hb_shape_plan_create_cached2:

 * @face: #hb_face_t to use

 * @props: The #hb_segment_properties_t of the segment

 * @user_features: (array length=num_user_features): The list of user-selected features

 * @num_user_features: The number of user-selected features

 * @coords: (array length=num_coords): The list of variation-space coordinates

 * @num_coords: The number of variation-space coordinates

 * @shaper_list: (array zero-terminated=1): List of shapers to try

 *

 * The variable-font version of #hb_shape_plan_create_cached.

 * Creates a cached shaping plan suitable for reuse, for a combination

 * of @face, @user_features, @props, and @shaper_list, plus the

 * variation-space coordinates @coords.

 *

 * Return value: (transfer full): The shaping plan

 *

 * Since: 1.4.0

 **/

hb_shape_plan_t *

hb_shape_plan_create_cached2 (hb_face_t                     *face,

            const hb_segment_properties_t *props,

            const hb_feature_t            *user_features,

            unsigned int                   num_user_features,

            const int                     *coords,

            unsigned int                   num_coords,

            const char * const            *shaper_list)

{

  DEBUG_MSG_FUNC (SHAPE_PLAN, nullptr,

      "face=%p num_features=%u shaper_list=%p",

      face,

      num_user_features,

      shaper_list);

retry:

  hb_face_t::plan_node_t *cached_plan_nodes = face->shape_plans;

  bool dont_cache = !hb_object_is_valid (face);

  if (likely (!dont_cache))

  {

    hb_shape_plan_key_t key;

    if (!key.init (false,

       face,

       props,

       user_features,

       num_user_features,

       coords,

       num_coords,

       shaper_list))

      return hb_shape_plan_get_empty ();

    for (hb_face_t::plan_node_t *node = cached_plan_nodes; node; node = node->next)

      if (node->shape_plan->key.equal (&key))

      {

  DEBUG_MSG_FUNC (SHAPE_PLAN, node->shape_plan, "fulfilled from cache");

  return hb_shape_plan_reference (node->shape_plan);

      }

  }

  hb_shape_plan_t *shape_plan = hb_shape_plan_create2 (face, props,

                   user_features, num_user_features,

                   coords, num_coords,

                   shaper_list);

  if (unlikely (dont_cache))

    return shape_plan;

  hb_face_t::plan_node_t *node = (hb_face_t::plan_node_t *) hb_calloc (1, sizeof (hb_face_t::plan_node_t));

  if (unlikely (!node))

    return shape_plan;

  node->shape_plan = shape_plan;

  node->next = cached_plan_nodes;

  if (unlikely (!face->shape_plans.cmpexch (cached_plan_nodes, node)))

  {

    hb_shape_plan_destroy (shape_plan);

    hb_free (node);

    goto retry;

  }

  DEBUG_MSG_FUNC (SHAPE_PLAN, shape_plan, "inserted into cache");

  return hb_shape_plan_reference (shape_plan);

}

#endif