#include <SkCanvas.h>

#include <SkPaint.h>

#include <SkTypeface.h>

#include <SkUtils.h>

#include "hb-private.hh"

#include "hb-sk.h"

#include "hb-font-private.hh"

#ifndef HB_DEBUG_FT

#define HB_DEBUG_FT (HB_DEBUG+0)

#endif

static hb_position_t SkiaScalarToHarfbuzzPosition(SkScalar value)

{

return value * 64;

}

static void SkiaSetPaint(SkPaint *paint, hb_skia_face_t *p_face, SkPaint::TextEncoding p_encoding)

{

// Skia APIs expect SkTypeface to be passed via a shared pointer

sk_sp<SkTypeface> t_typeface(p_face->typeface);

t_typeface->ref();

paint -> setTextEncoding(p_encoding);

paint -> setTextSize(p_face -> size);

paint -> setTypeface(t_typeface);

}

static void SkiaGetGlyphWidthAndExtents(SkPaint* paint, hb_skia_face_t *p_face, hb_codepoint_t codepoint, hb_position_t* width, hb_glyph_extents_t* extents)

{

SkiaSetPaint(paint, p_face, SkPaint::kGlyphID_TextEncoding);

SkScalar skWidth;

SkRect skBounds;

uint16_t glyph = codepoint;

paint->getTextWidths(&glyph, sizeof(glyph), &skWidth, &skBounds);

if (width)

*width = SkiaScalarToHarfbuzzPosition(skWidth);

if (extents) {

extents->x_bearing = SkiaScalarToHarfbuzzPosition(skBounds.fLeft);

extents->y_bearing = SkiaScalarToHarfbuzzPosition(skBounds.fTop);

extents->width = SkiaScalarToHarfbuzzPosition(skBounds.width());

extents->height = SkiaScalarToHarfbuzzPosition(skBounds.height());

}

}

static hb_bool_t

hb_sk_get_glyph (hb_font_t *font HB_UNUSED,

void *font_data,

hb_codepoint_t unicode,

hb_codepoint_t variation_selector,

hb_codepoint_t *glyph,

void *user_data HB_UNUSED)

{

hb_skia_face_t *typeface = (hb_skia_face_t *)font_data;

SkPaint paint;

SkiaSetPaint(&paint, typeface, SkPaint::kUTF16_TextEncoding);

uint16_t text[4];

size_t length = SkUTF16_FromUnichar(unicode, text);

uint16_t glyph16;

paint.textToGlyphs(text, length, &glyph16);

*glyph = glyph16;

return true;

}

static hb_position_t

hb_sk_get_glyph_h_advance (hb_font_t *font HB_UNUSED,

void *font_data,

hb_codepoint_t glyph,

void *user_data HB_UNUSED)

{

hb_skia_face_t *typeface = (hb_skia_face_t *)font_data;

SkPaint paint;

hb_position_t advance = 0;

SkiaGetGlyphWidthAndExtents(&paint, typeface, glyph, &advance, 0);

return advance;

}

static hb_position_t

hb_sk_get_glyph_v_advance (hb_font_t *font HB_UNUSED,

void *font_data,

hb_codepoint_t glyph,

void *user_data HB_UNUSED)

{

return 0;

}

static hb_bool_t

hb_sk_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_sk_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_sk_get_glyph_h_kerning (hb_font_t *font,

void *font_data,

hb_codepoint_t left_glyph,

hb_codepoint_t right_glyph,

void *user_data HB_UNUSED)

{

return 0;

}

static hb_position_t

hb_sk_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)

{

return 0;

}

static hb_bool_t

hb_sk_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)

{

hb_skia_face_t *typeface = (hb_skia_face_t *)font_data;

SkPaint paint;

SkiaGetGlyphWidthAndExtents(&paint, typeface, glyph, 0, extents);

return true;

}

static hb_bool_t

hb_sk_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)

{

return false;

}

static hb_bool_t

hb_sk_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_sk_get_glyph_from_name (hb_font_t *font HB_UNUSED,

void *font_data,

const char *name, int len, /* -1 means nul-terminated */

hb_codepoint_t *glyph,

void *user_data HB_UNUSED)

{

return false;

}

static hb_font_funcs_t *

_hb_sk_get_font_funcs (void)

{

static hb_font_funcs_t* hb_sk_font_funcs = 0;

if (!hb_sk_font_funcs)

{

hb_sk_font_funcs = hb_font_funcs_create();

hb_font_funcs_set_glyph_func(hb_sk_font_funcs, hb_sk_get_glyph, 0, 0);

hb_font_funcs_set_glyph_h_advance_func(hb_sk_font_funcs, hb_sk_get_glyph_h_advance, 0, 0);

hb_font_funcs_set_glyph_v_advance_func(hb_sk_font_funcs, hb_sk_get_glyph_v_advance, 0, 0);

hb_font_funcs_set_glyph_h_origin_func(hb_sk_font_funcs, hb_sk_get_glyph_h_origin, 0, 0);

hb_font_funcs_set_glyph_v_origin_func(hb_sk_font_funcs, hb_sk_get_glyph_v_origin, 0, 0);

hb_font_funcs_set_glyph_h_kerning_func(hb_sk_font_funcs, hb_sk_get_glyph_h_kerning, 0, 0);

hb_font_funcs_set_glyph_v_kerning_func(hb_sk_font_funcs, hb_sk_get_glyph_v_kerning, 0, 0);

hb_font_funcs_set_glyph_extents_func(hb_sk_font_funcs, hb_sk_get_glyph_extents, 0, 0);

hb_font_funcs_set_glyph_contour_point_func(hb_sk_font_funcs, hb_sk_get_glyph_contour_point, 0, 0);

}

return hb_sk_font_funcs;

}

static hb_blob_t *

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

{

hb_skia_face_t *hbs_face = (hb_skia_face_t *)user_data;

const size_t tableSize = hbs_face -> typeface -> getTableSize(tag);

if (!tableSize)

return 0;

char* buffer = reinterpret_cast<char*>(malloc(tableSize));

if (!buffer)

return 0;

size_t actualSize = hbs_face -> typeface -> getTableData(tag, 0, tableSize, buffer);

if (tableSize != actualSize)

{

free(buffer);

return 0;

}

return hb_blob_create((const char*)buffer, tableSize, HB_MEMORY_MODE_WRITABLE, buffer, free);

}

hb_face_t *

hb_sk_face_create (hb_skia_face_t *p_face, hb_destroy_func_t destroy)

{

hb_face_t* face = hb_face_create_for_tables(reference_table, p_face, 0);

return face;

}

static void

hb_sk_face_finalize (hb_skia_face_t *p_typeface)

{

}

void hb_sk_set_face(MCHarfbuzzSkiaFace *p_face, hb_skia_face_t *p_hb_sk_face)

{

if (p_face -> face != 0)

hb_face_destroy(p_face -> face);

p_face -> face = hb_sk_face_create (p_hb_sk_face, 0);

}

static void hb_sk_font_destroy(void *user_data)

{

hb_font_t *t_font = reinterpret_cast<hb_font_t *>(user_data);

delete t_font;

}

hb_font_t *

hb_sk_font_create (MCHarfbuzzSkiaFace *typeface, hb_destroy_func_t destroy)

{

hb_font_t *font;

font = hb_font_create (typeface -> face);

uint16_t t_size = typeface -> skia_face -> size;

hb_font_set_funcs (font, _hb_sk_get_font_funcs (),

typeface -> skia_face, (hb_destroy_func_t) hb_sk_font_destroy);

hb_font_set_scale (font, t_size, t_size);

int scale = t_size * (1 << 16) / 1000;

hb_font_set_ppem (font, scale, scale);

return font;

}