/*

 * Copyright © 2022 Behdad Esfahbod

 *

 *  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.

 */

#include "hb.hh"

#ifndef HB_NO_PAINT

#include "hb-paint-extents.hh"

#include "hb-draw.hh"

#include "hb-machinery.hh"

/*

 * This file implements bounds-extraction computation of COLRv1 fonts as described in:

 *

 * https://learn.microsoft.com/en-us/typography/opentype/spec/colr#glyph-metrics-and-boundedness

 */

static void

hb_paint_extents_push_transform (hb_paint_funcs_t *funcs HB_UNUSED,

         void *paint_data,

         float xx, float yx,

         float xy, float yy,

         float dx, float dy,

         void *user_data HB_UNUSED)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  c->push_transform (hb_transform_t<> {xx, yx, xy, yy, dx, dy});

}

static void

hb_paint_extents_pop_transform (hb_paint_funcs_t *funcs HB_UNUSED,

              void *paint_data,

        void *user_data HB_UNUSED)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  c->pop_transform ();

}

/* Like the hb_draw_extents_get_funcs() sink, but tied to the paint

 * session's live work budget. */

struct hb_paint_extents_sink_t

{

  hb_extents_t<> extents;

  int64_t *budget_remaining;

  bool consume_segment ()

  {

    return hb_budget_spend (*budget_remaining, HB_BUDGET_1);

  }

};

static void

hb_paint_extents_count_move_to (hb_draw_funcs_t *dfuncs HB_UNUSED, void *data,

        hb_draw_state_t *st HB_UNUSED,

        float to_x, float to_y,

        void *user_data HB_UNUSED)

{

  hb_paint_extents_sink_t *sink = (hb_paint_extents_sink_t *) data;

  if (unlikely (!sink->consume_segment ())) return;

  sink->extents.add_point (to_x, to_y);

}

static void

hb_paint_extents_count_line_to (hb_draw_funcs_t *dfuncs HB_UNUSED, void *data,

        hb_draw_state_t *st HB_UNUSED,

        float to_x, float to_y,

        void *user_data HB_UNUSED)

{

  hb_paint_extents_sink_t *sink = (hb_paint_extents_sink_t *) data;

  if (unlikely (!sink->consume_segment ())) return;

  sink->extents.add_point (to_x, to_y);

}

static void

hb_paint_extents_count_quadratic_to (hb_draw_funcs_t *dfuncs HB_UNUSED, void *data,

             hb_draw_state_t *st HB_UNUSED,

             float control_x, float control_y,

             float to_x, float to_y,

             void *user_data HB_UNUSED)

{

  hb_paint_extents_sink_t *sink = (hb_paint_extents_sink_t *) data;

  if (unlikely (!sink->consume_segment ())) return;

  sink->extents.add_point (control_x, control_y);

  sink->extents.add_point (to_x, to_y);

}

static void

hb_paint_extents_count_cubic_to (hb_draw_funcs_t *dfuncs HB_UNUSED, void *data,

         hb_draw_state_t *st HB_UNUSED,

         float control1_x, float control1_y,

         float control2_x, float control2_y,

         float to_x, float to_y,

         void *user_data HB_UNUSED)

{

  hb_paint_extents_sink_t *sink = (hb_paint_extents_sink_t *) data;

  if (unlikely (!sink->consume_segment ())) return;

  sink->extents.add_point (control1_x, control1_y);

  sink->extents.add_point (control2_x, control2_y);

  sink->extents.add_point (to_x, to_y);

}

static int64_t *

hb_paint_extents_get_budget_remaining (hb_draw_funcs_t *, void *draw_data, void *)

{

  return ((hb_paint_extents_sink_t *) draw_data)->budget_remaining;

}

static inline void free_static_paint_extents_draw_funcs ();

static struct hb_paint_extents_draw_funcs_lazy_loader_t : hb_draw_funcs_lazy_loader_t<hb_paint_extents_draw_funcs_lazy_loader_t>

{

  static hb_draw_funcs_t *create ()

  {

    hb_draw_funcs_t *funcs = hb_draw_funcs_create ();

    hb_draw_funcs_set_move_to_func (funcs, hb_paint_extents_count_move_to, nullptr, nullptr);

    hb_draw_funcs_set_line_to_func (funcs, hb_paint_extents_count_line_to, nullptr, nullptr);

    hb_draw_funcs_set_quadratic_to_func (funcs, hb_paint_extents_count_quadratic_to, nullptr, nullptr);

    hb_draw_funcs_set_cubic_to_func (funcs, hb_paint_extents_count_cubic_to, nullptr, nullptr);

    hb_draw_funcs_set_get_budget_remaining_func (funcs, hb_paint_extents_get_budget_remaining, nullptr, nullptr);

    hb_draw_funcs_make_immutable (funcs);

    hb_atexit (free_static_paint_extents_draw_funcs);

    return funcs;

  }

} static_paint_extents_draw_funcs;

static inline

void free_static_paint_extents_draw_funcs ()

{

  static_paint_extents_draw_funcs.free_instance ();

}

static void

hb_paint_extents_push_clip_glyph (hb_paint_funcs_t *funcs HB_UNUSED,

          void *paint_data,

          hb_codepoint_t glyph,

          hb_font_t *font,

          void *user_data HB_UNUSED)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  hb_paint_extents_sink_t sink {{}, &c->budget_remaining};

  /* Skip the outline extraction when the session work budget is

   * spent; an empty clip clips everything out. */

  if (likely (c->budget_remaining >= 0))

    hb_font_draw_glyph (font, glyph, static_paint_extents_draw_funcs.get_unconst (), &sink);

  c->push_clip (sink.extents);

}

static void

hb_paint_extents_push_clip_rectangle (hb_paint_funcs_t *funcs HB_UNUSED,

              void *paint_data,

              float xmin, float ymin, float xmax, float ymax,

              void *user_data)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  hb_extents_t<> extents = {xmin, ymin, xmax, ymax};

  c->push_clip (extents);

}

static void

hb_paint_extents_pop_clip (hb_paint_funcs_t *funcs HB_UNUSED,

         void *paint_data,

         void *user_data HB_UNUSED)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  c->pop_clip ();

}

static void

hb_paint_extents_push_group (hb_paint_funcs_t *funcs HB_UNUSED,

           void *paint_data,

           void *user_data HB_UNUSED)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  c->push_group ();

}

static void

hb_paint_extents_pop_group (hb_paint_funcs_t *funcs HB_UNUSED,

          void *paint_data,

          hb_paint_composite_mode_t mode,

          void *user_data HB_UNUSED)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  c->pop_group (mode);

}

static hb_bool_t

hb_paint_extents_paint_image (hb_paint_funcs_t *funcs HB_UNUSED,

            void *paint_data,

            hb_blob_t *blob HB_UNUSED,

            unsigned int width HB_UNUSED,

            unsigned int height HB_UNUSED,

            hb_tag_t format HB_UNUSED,

            float slant HB_UNUSED,

            hb_glyph_extents_t *glyph_extents,

            void *user_data HB_UNUSED)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  if (!glyph_extents)

    return false; // Happens with SVG images.

  hb_extents_t<> extents = {(float) glyph_extents->x_bearing,

          (float) glyph_extents->y_bearing + glyph_extents->height,

          (float) glyph_extents->x_bearing + glyph_extents->width,

          (float) glyph_extents->y_bearing};

  c->push_clip (extents);

  c->paint ();

  c->pop_clip ();

  return true;

}

static void

hb_paint_extents_paint_color (hb_paint_funcs_t *funcs HB_UNUSED,

            void *paint_data,

            hb_bool_t use_foreground HB_UNUSED,

            hb_color_t color HB_UNUSED,

            void *user_data HB_UNUSED)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  c->paint ();

}

static void

hb_paint_extents_paint_linear_gradient (hb_paint_funcs_t *funcs HB_UNUSED,

                void *paint_data,

                hb_color_line_t *color_line HB_UNUSED,

                float x0 HB_UNUSED, float y0 HB_UNUSED,

                float x1 HB_UNUSED, float y1 HB_UNUSED,

                float x2 HB_UNUSED, float y2 HB_UNUSED,

                void *user_data HB_UNUSED)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  c->paint ();

}

static void

hb_paint_extents_paint_radial_gradient (hb_paint_funcs_t *funcs HB_UNUSED,

                void *paint_data,

                hb_color_line_t *color_line HB_UNUSED,

                float x0 HB_UNUSED, float y0 HB_UNUSED, float r0 HB_UNUSED,

                float x1 HB_UNUSED, float y1 HB_UNUSED, float r1 HB_UNUSED,

                void *user_data HB_UNUSED)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  c->paint ();

}

static void

hb_paint_extents_paint_sweep_gradient (hb_paint_funcs_t *funcs HB_UNUSED,

               void *paint_data,

               hb_color_line_t *color_line HB_UNUSED,

               float cx HB_UNUSED, float cy HB_UNUSED,

               float start_angle HB_UNUSED,

               float end_angle HB_UNUSED,

               void *user_data HB_UNUSED)

{

  hb_paint_extents_context_t *c = (hb_paint_extents_context_t *) paint_data;

  c->paint ();

}

static hb_bool_t

hb_paint_extents_set_budget (hb_paint_funcs_t *, void *paint_data,

           int64_t budget, void *)

{

  auto *context = (hb_paint_extents_context_t *) paint_data;

  context->budget = budget;

  context->budget_initialized = true;

  context->recharge_budget ();

  return true;

}

static int64_t

hb_paint_extents_get_budget (hb_paint_funcs_t *, void *paint_data, void *)

{

  return ((hb_paint_extents_context_t *) paint_data)->budget;

}

static int64_t *

hb_paint_extents_get_budget_remaining (hb_paint_funcs_t *, void *paint_data, void *)

{

  return &((hb_paint_extents_context_t *) paint_data)->budget_remaining;

}

static inline void free_static_paint_extents_funcs ();

static struct hb_paint_extents_funcs_lazy_loader_t : hb_paint_funcs_lazy_loader_t<hb_paint_extents_funcs_lazy_loader_t>

{

  static hb_paint_funcs_t *create ()

  {

    hb_paint_funcs_t *funcs = hb_paint_funcs_create ();

    hb_paint_funcs_set_push_transform_func (funcs, hb_paint_extents_push_transform, nullptr, nullptr);

    hb_paint_funcs_set_pop_transform_func (funcs, hb_paint_extents_pop_transform, nullptr, nullptr);

    hb_paint_funcs_set_push_clip_glyph_func (funcs, hb_paint_extents_push_clip_glyph, nullptr, nullptr);

    hb_paint_funcs_set_push_clip_rectangle_func (funcs, hb_paint_extents_push_clip_rectangle, nullptr, nullptr);

    hb_paint_funcs_set_pop_clip_func (funcs, hb_paint_extents_pop_clip, nullptr, nullptr);

    hb_paint_funcs_set_push_group_func (funcs, hb_paint_extents_push_group, nullptr, nullptr);

    hb_paint_funcs_set_pop_group_func (funcs, hb_paint_extents_pop_group, nullptr, nullptr);

    hb_paint_funcs_set_color_func (funcs, hb_paint_extents_paint_color, nullptr, nullptr);

    hb_paint_funcs_set_image_func (funcs, hb_paint_extents_paint_image, nullptr, nullptr);

    hb_paint_funcs_set_linear_gradient_func (funcs, hb_paint_extents_paint_linear_gradient, nullptr, nullptr);

    hb_paint_funcs_set_radial_gradient_func (funcs, hb_paint_extents_paint_radial_gradient, nullptr, nullptr);

    hb_paint_funcs_set_sweep_gradient_func (funcs, hb_paint_extents_paint_sweep_gradient, nullptr, nullptr);

    hb_paint_funcs_set_set_budget_func (funcs, hb_paint_extents_set_budget, nullptr, nullptr);

    hb_paint_funcs_set_get_budget_func (funcs, hb_paint_extents_get_budget, nullptr, nullptr);

    hb_paint_funcs_set_get_budget_remaining_func (funcs, hb_paint_extents_get_budget_remaining, nullptr, nullptr);

    hb_paint_funcs_make_immutable (funcs);

    hb_atexit (free_static_paint_extents_funcs);

    return funcs;

  }

} static_paint_extents_funcs;

static inline

void free_static_paint_extents_funcs ()

{

  static_paint_extents_funcs.free_instance ();

}

hb_paint_funcs_t *

hb_paint_extents_get_funcs ()

{

  return static_paint_extents_funcs.get_unconst ();

}

#endif