module dlib.externdecl;

import dlib.aliases;

enum stbtt_curvetype : u8
{
	none,
	vmove,
	vline,
	vcurve,
	vcubic,
}

alias stbtt_vertex_type = short;

struct stbtt__buf
{
	u8* data;
	i32 cursor;
	i32 size;
}

struct stbtt_vertex
{
	stbtt_vertex_type x, y, cx, cy, cx1, cy1;
	stbtt_curvetype   type;
  u8	              padding;
}

struct stbtt_fontinfo
{
	void* userdata;
	u8*   data;
	i32   fontstart;

	i32   numGlyphs;

	i32 loca, head, glyf, hhea, hmtx, kern, gpos, svg;
	i32 index_map;
	i32 indexToLocFormat;

	stbtt__buf cff;
	stbtt__buf charstrings;
	stbtt__buf gsubrs;
	stbtt__buf subrs;
	stbtt__buf fontdicts;
	stbtt__buf fdselect;
}

extern(C):

// stb_truetype

i32
stbtt_FindGlyphIndex(const stbtt_fontinfo* info, i32 unicode_codepoint);

void
stbtt_GetGlyphHMetrics(const stbtt_fontinfo* info, i32 glyph_index, i32* advanceWidth, i32* leftSideBearing);

i32
stbtt_GetGlyphShape(const stbtt_fontinfo* info, i32 glyph_index, stbtt_vertex** pvertices);

void
stbtt_FreeShape(const stbtt_fontinfo* info, stbtt_vertex* v);

f32
stbtt_ScaleForPixelHeight(const stbtt_fontinfo* info, f32 height);

void
stbtt_GetFontVMetrics(const stbtt_fontinfo* info, i32* ascent, i32* descent, i32* lineGap);

i32
stbtt_InitFont(stbtt_fontinfo* info, const(u8*) data, i32 offset);

i32
stbtt_GetGlyphBox(const stbtt_fontinfo* info, i32 glyph_index, i32* x0, i32* y0, i32* x1, i32* y1);

i32
stbtt_GetFontOffsetForIndex(const(u8*) data, i32 index);

// tinyalloc

version(WebAssembly)
{
	void
	ta_init(const usize heap_blocks, const usize split_thresh, const usize alignment);

	void*
	malloc(usize size) nothrow @nogc;

	void*
	calloc(usize size, usize count);

	void
	free(void *ptr);

	void*
	realloc(void *ptr, usize size);
}