// based on system packaged freetype 2.11.1 on Ubuntu 22.04
// @INCOMPLETE

package freetype

import "core:c"

FT_Error :: c.int
@private
FT_Short  :: c.short
@private
FT_UShort  :: c.ushort
@private
FT_Int  :: c.int
@private
FT_UInt  :: c.uint
@private
FT_Long  :: c.long
ULong :: c.ulong
@private
FT_String :: c.char
@private
FT_UInt32 :: c.uint

@private
FT_Pos :: c.long
@private
FT_Fixed :: c.long
@private
FT_SubGlyph :: rawptr // internal object
@private
FT_Slot_Internal :: rawptr // opaque handle to internal slot structure
@private
FT_Size_Internal :: rawptr // opaque handle to internal size structure
@private
FT_Driver :: rawptr // a handle to a given FreeType font driver object
@private
FT_Memory :: rawptr // a handle to a given memory manager object
@private
FT_Face_Internal :: rawptr

Library :: rawptr // handle to a library object

@private
FT_Render_Mode_ :: enum {
  NORMAL = 0,
  LIGHT,
  MONO,
  LCD,
  LCD_V,
  SDF,

  MAX
}

@private
LoadFlags :: enum {
  DEFAULT                     = 0x0,
  NO_SCALE                    = 1 << 0,
  NO_HINTING                  = 1 << 1,
  RENDER                      = 1 << 2,
  NO_BITMAP                   = 1 << 3,
  VERTICAL_LAYOUT             = 1 << 4,
  FORCE_AUTOHINT              = 1 << 5,
  CROP_BITMAP                 = 1 << 6,
  PEDANTIC                    = 1 << 7,
  IGNORE_GLOBAL_ADVANCE_WIDTH = 1 << 9,
  NO_RECURSE                  = 1 << 10,
  IGNORE_TRANSFORM            = 1 << 11,
  MONOCHROME                  = 1 << 12,
  LINEAR_DESIGN               = 1 << 13,
  NO_AUTOHINT                 = 1 << 15,
  // Bits 16-19 are used by `FT_LOAD_TARGET_`
  COLOR                       = 1 << 20,
  COMPUTE_METRICS             = 1 << 21,
  BITMAP_METRICS_ONLY         = 1 << 22,

  /* used internally only by certain font drivers */
  ADVANCE_ONLY                = 1 << 8,
  SBITS_ONLY                  = 1 << 14,

  FT_LOAD_TARGET_NORMAL       = (int(FT_Render_Mode_.NORMAL) & 15) << 16,
  FT_LOAD_TARGET_LIGHT        = (int(FT_Render_Mode_.LIGHT)  & 15) << 16,
  FT_LOAD_TARGET_MONO         = (int(FT_Render_Mode_.MONO)   & 15) << 16,
  FT_LOAD_TARGET_LCD          = (int(FT_Render_Mode_.LCD)    & 15) << 16,
  FT_LOAD_TARGET_LCD_V        = (int(FT_Render_Mode_.LCD_V)  & 15) << 16,
}

#assert(size_of(OutlineFlags) == 8)

@private
OutlineFlags :: enum {
  NONE             = 0x0,
  OWNER            = 0x1,
  EVEN_ODD_FILL    = 0x2,
  REVERSE_FILL     = 0x4,
  IGNORE_DROPOUTS  = 0x8,
  SMART_DROPOUTS   = 0x10,
  INCLUDE_STUBS    = 0x20,
  OVERLAP          = 0x40,

  HIGH_PRECISION   = 0x100,
  SINGLE_PASS      = 0x200,
}

@private
FT_Encoding :: enum u32 {
  NONE = 0,
  MS_SYMBOL = ('s' << 24) | ('y' << 16) | ('m' << 8) | 'b',
  UNICODE   = ('u' << 24) | ('n' << 16) | ('i' << 8) | 'c',
  SJIS      = ('s' << 24) | ('j' << 16) | ('i' << 8) | 's',
  PRC       = ('g' << 24) | ('b' << 16) | (' ' << 8) | ' ',
  BIG5      = ('b' << 24) | ('i' << 16) | ('g' << 8) | '5',
  WANSUNG   = ('w' << 24) | ('a' << 16) | ('n' << 8) | 's',
  JOHAB     = ('j' << 24) | ('o' << 16) | ('h' << 8) | 'a',

  /* for backward compatibility */
  GB2312     = PRC,
  MS_SJIS    = SJIS,
  MS_GB2312  = PRC,
  MS_BIG5    = BIG5,
  MS_WANSUNG = WANSUNG,
  MS_JOHAB   = JOHAB,

  ADOBE_STANDARD  = ('A' << 24) | ('D' << 16) | ('O' << 8) | 'B',
  ADOBE_EXPERT    = ('A' << 24) | ('D' << 16) | ('B' << 8) | 'E',
  ADOBE_CUSTOM    = ('A' << 24) | ('D' << 16) | ('B' << 8) | 'C',
  ADOBE_LATIN_1   = ('l' << 24) | ('a' << 16) | ('t' << 8) | '1',

  OLD_LATIN_2  = ('l' << 24) | ('a' << 16) | ('t' << 8) | '2',

  APPLE_ROMAN  = ('a' << 24) | ('r' << 16) | ('m' << 8) | 'n',
}

#assert(size_of(FT_CharMapRec_) == 16)

@private
FT_CharMapRec_ :: struct {
  face: Face,
  encoding: FT_Encoding,
  platform_id: FT_UShort,
  encoding_id: FT_UShort,
}

@private
FT_CharMap :: ^FT_CharMapRec_

#assert(size_of(FT_Bitmap_Size) == (16 when (ODIN_OS == .Windows) else 32))

@private
FT_Bitmap_Size :: struct {
  height: FT_Short,
  width: FT_Short,

  size: FT_Pos,

  x_ppem: FT_Pos,
  y_ppem: FT_Pos,
}

#assert(size_of(FT_Generic) == 16)

@private
FT_Generic :: struct {
  data: rawptr,
  finalizer: ^proc(object: rawptr),
}

#assert(size_of(FT_BBox) == (16 when (ODIN_OS == .Windows) else 32))

@private
FT_BBox :: struct {
  xMin, yMin: FT_Pos,
  xMax, yMax: FT_Pos,
}

#assert(size_of(FT_Vector) == (8 when (ODIN_OS == .Windows) else 16))

@private
FT_Vector :: struct {
  x, y: FT_Pos,
}

#assert(size_of(FT_Glyph_Metrics) == (32 when (ODIN_OS == .Windows) else 64))

@private
FT_Glyph_Metrics :: struct {
  width: FT_Pos,
  height: FT_Pos,

  horiBearingX: FT_Pos,
  horiBearingY: FT_Pos,
  horiAdvance: FT_Pos,

  vertBearingX: FT_Pos,
  vertBearingY: FT_Pos,
  vertAdvance: FT_Pos,
}

#assert(size_of(FT_Outline) == 40)

@private
FT_Outline :: struct {
  n_contours: i16,
  n_points: i16,

  points: ^FT_Vector,
  tags: ^i8,
  contours: ^i16,

  flags: OutlineFlags,
}

#assert(size_of(FT_Glyph_Format) == 8)

@private
FT_Glyph_Format :: enum {
  NONE = (0 << 24) | (0 << 16) | (0 << 8) | 0,

  COMPOSITE  = ('c' << 24) | ('o' << 16) | ('m' << 8) | 'p',
  BITMAP     = ('b' << 24) | ('i' << 16) | ('t' << 8) | 's',
  OUTLINE    = ('o' << 24) | ('u' << 16) | ('t' << 8) | 'l',
  PLOTTER    = ('p' << 24) | ('l' << 16) | ('o' << 8) | 't'
}

// linux: 304
// windows: 248
// windows: 236 packed
#assert(size_of(FT_GlyphSlotRec_) == (248 when (ODIN_OS == .Windows) else 304))

FT_GlyphSlotRec_ :: struct {
  library: Library,
  face: Face,
  next: FT_GlyphSlot,
  glyph_index: FT_UInt, /* new in 2.10; was reserved previously */
  generic: FT_Generic,

  metrics: FT_Glyph_Metrics,
  linearHoriAdvance: FT_Fixed,
  linearVertAdvance: FT_Fixed,
  advance: FT_Vector,

  format: FT_Glyph_Format,

  bitmap: Bitmap,
  bitmap_left: FT_Int,
  bitmap_top: FT_Int,

  outline: FT_Outline,

  num_subglyphs: FT_UInt,
  subglyphs: FT_SubGlyph,

  control_data: rawptr,
  control_len: c.long,

  lsb_delta: FT_Pos,
  rsb_delta: FT_Pos,

  other: rawptr,

  internal: FT_Slot_Internal,
}

@private
FT_GlyphSlot :: ^FT_GlyphSlotRec_

#assert(size_of(FT_Size_Metrics) == (28 when (ODIN_OS == .Windows) else 56))

@private
FT_Size_Metrics :: struct {
  x_ppem: FT_UShort,      /* horizontal pixels per EM               */
  y_ppem: FT_UShort,      /* vertical pixels per EM                 */

  x_scale: FT_Fixed,     /* scaling values used to convert font    */
  y_scale: FT_Fixed,     /* units to 26.6 fractional pixels        */

  ascender: FT_Pos,    /* ascender in 26.6 frac. pixels          */
  descender: FT_Pos,   /* descender in 26.6 frac. pixels         */
  height: FT_Pos,      /* text height in 26.6 frac. pixels       */
  max_advance: FT_Pos, /* max horizontal advance, in 26.6 pixels */
}

// linux: 88
// windows: 64 (has 4 bytes padding)
// windows: 60 packed
#assert(size_of(FT_SizeRec) == (64 when (ODIN_OS == .Windows) else 88))

@private
FT_SizeRec :: struct {
  face: Face,
  generic: FT_Generic,
  metrics: FT_Size_Metrics,
  internal: FT_Size_Internal,
}

@private
FT_Size :: ^FT_SizeRec

#assert(size_of(FT_StreamDesc) == 8)

@private
FT_StreamDesc :: struct #raw_union {
  value: i64,
  pointer: rawptr,
}

@private
FT_Stream_IoFunc :: #type ^proc(stream: FT_Stream, offset: u64, buffer: [^]u8, count: u64) -> u64
@private
FT_Stream_CloseFunc :: #type ^proc(stream: FT_Stream)

#assert(size_of(FT_StreamRec_) == 80)

@private
FT_StreamRec_ :: struct {
  base: [^]u8,
  size: u64,
  pos: u64,

  descriptor: FT_StreamDesc,
  pathname: FT_StreamDesc,
  read: FT_Stream_IoFunc,
  close: FT_Stream_CloseFunc,

  memory: FT_Memory,
  cursor: [^]u8,
  limit: [^]u8,
}

@private
FT_Stream :: ^FT_StreamRec_

#assert(size_of(FT_ListNodeRec_) == 24)

@private
FT_ListNodeRec_ :: struct {
  prev: FT_ListNode,
  next: FT_ListNode,
  data: rawptr,
}

@private
FT_ListNode :: ^FT_ListNodeRec_

#assert(size_of(FT_ListRec) == 16)

@private
FT_ListRec :: struct {
  head: FT_ListNode,
  tail: FT_ListNode,
}

// linux: 248
// windows: 216
// windows packed: 204
#assert(size_of(FT_FaceRec_) == (216 when (ODIN_OS == .Windows) else 248))

@private
FT_FaceRec_ :: struct {
  num_faces: FT_Long,
  face_index: FT_Long,

  face_flags: FT_Long,
  style_flags: FT_Long,

  num_glyphs: FT_Long,

  family_name: ^FT_String,
  style_name: ^FT_String,

  num_fixed_sizes: FT_Int,
  available_sizes: ^FT_Bitmap_Size,

  num_charmaps: FT_Int,
  charmaps: ^FT_CharMap,

  generic: FT_Generic,

  /*# The following member variables (down to `underline_thickness`) */
  /*# are only relevant to scalable outlines; cf. @FT_Bitmap_Size    */
  /*# for bitmap fonts.                                              */
  bbox: FT_BBox,

  units_per_EM: FT_UShort,
  ascender: FT_Short,
  descender: FT_Short,
  height: FT_Short,

  max_advance_width: FT_Short,
  max_advance_height: FT_Short,

  underline_position: FT_Short,
  underline_thickness: FT_Short,

  glyph: FT_GlyphSlot,
  size: FT_Size,
  charmap: FT_CharMap,

  /*@private begin */
  driver: FT_Driver,
  memory: FT_Memory,
  stream: FT_Stream,

  sizes_list: FT_ListRec,

  autohint: FT_Generic, // face-specific auto-hinter data
  extensions: rawptr,   // unused

  internal: FT_Face_Internal,

  /*@private end */
}

Face :: ^FT_FaceRec_

#assert(size_of(Bitmap) == 40)

Bitmap :: struct {
  rows: u32,
  width: u32,
  pitch: i32,
  buffer: [^]u8,
  num_grays: u16,
  pixel_mode: u8,
  palette_mode: u8,
  palette: rawptr,
}