#include <stdint.h>

#ifdef TRACE_BLOCKS
#define KBTS_INSTRUMENT_BLOCK_BEGIN(Name) printf("<%s>\n", #Name)
#define KBTS_INSTRUMENT_BLOCK_END(Name) printf("</%s>\n", #Name)
#define KBTS_INSTRUMENT_FUNCTION_BEGIN
#define KBTS_INSTRUMENT_FUNCTION_END
#endif

#include "kb_text_shape.h"
#include "kb_text_shape.inc"

void hs_ShapeCurrentCodepointsIterator(kbts_shape_context *Context, kbts_shape_codepoint_iterator *It)
{
  *It = kbts__InputCodepointIterator(Context, 0, Context->InputCodepointCount);
}

void hs_CodepointToGlyph(kbts_font *Font, int Codepoint, kbts_glyph_config *Config, int UserId, kbts_glyph *Glyph)
{
  *Glyph = kbts_CodepointToGlyph(Font, Codepoint, Config, UserId);
}

void hs_ActiveGlyphIterator(kbts_glyph_storage *Storage, kbts_glyph_iterator *It) {
  *It = kbts_ActiveGlyphIterator(Storage);
}

kbts_load_font_error hs_FontFromFile(const char *FileName, int FontIndex, kbts_allocator_function *Allocator, void *AllocatorData, void **FileData, int *FileSize_, kbts_font *Font) {
 *Font = kbts_FontFromFile(FileName, FontIndex, Allocator, AllocatorData, FileData, FileSize_);
 return Font->Error;
}

kbts_load_font_error hs_FontFromMemory(void *FileData, int FileSize, int FontIndex, kbts_allocator_function *Allocator, void *AllocatorData, kbts_font *Font) {
 *Font = kbts_FontFromMemory(FileData, FileSize, FontIndex, Allocator, AllocatorData);
 return Font->Error;
}

uint16_t hs_GetCapHeight(kbts_font *Font) {
    if (!Font || !Font->Blob) return 0;

    kbts_blob_header *Header = Font->Blob;
    kbts_blob_table *TableEntry = &Header->Tables[KBTS_BLOB_TABLE_ID_OS2];
    if (TableEntry->Length < 90) return 0;

    uint8_t *BlobStart = (uint8_t *)Header;
    uint8_t *TableData = BlobStart + TableEntry->OffsetFromStartOfFile;

    uint16_t CapHeight;
    memcpy(&CapHeight, TableData + 88, sizeof(uint16_t));

    return CapHeight;
}


uint16_t hs_GetUnitsPerEm(kbts_font *Font) {
    if (!Font || !Font->Blob) return 0;

    kbts_blob_header *Header = Font->Blob;

    // Access the entry for the 'head' table
    kbts_blob_table *HeadTableEntry = &Header->Tables[KBTS_BLOB_TABLE_ID_HEAD];

    // Ensure the table exists and is large enough (min length is usually 54 bytes)
    if (HeadTableEntry->Length < 20) return 0;

    // Calculate the pointer to the table data
    // Note: Offsets are relative to the start of the blob header
    uint8_t *BlobStart = (uint8_t *)Header;
    uint8_t *HeadTableData = BlobStart + HeadTableEntry->OffsetFromStartOfFile;

    // The library stores the Blob data in Native Endian.
    // We use memcpy to safely read the 16-bit integer without violating alignment rules.
    uint16_t UnitsPerEm;
    memcpy(&UnitsPerEm, HeadTableData + 18, sizeof(uint16_t));

    return UnitsPerEm;
}