wrapper.nim

type
  RawSecp256k1Context* = distinct pointer
  RawSecp256k1ScratchSpace* = distinct pointer

  Secp256k1Context* = ref object
    raw*: RawSecp256k1Context

  Secp256k1ScratchSpace* = ref object
    raw*: RawSecp256k1ScratchSpace

  Secp256k1Pubkey* = object
    data*: array[64, cuchar]

  Secp256k1EcdsaSignature* = object
    data*: array[64, cuchar]

  Secp256k1NonceFunction* = proc (
    nonce32: ptr cuchar;
    msg32:   ptr cuchar;
    key32:   ptr cuchar;
    algo16:  ptr cuchar;
    data:    pointer;
    attempt: cuint): cint {.cdecl.}


const
  secp256k1FlagsTypeMask*        = (1 shl 8) - 1
  secp256k1FlagsTypeContext*     = (1 shl 0)
  secp256k1FlagsTypeCompression* = (1 shl 1)


const
  secp256k1FlagsBitContextVerify* = (1 shl 8)
  secp256k1FlagsBitContextSign*   = (1 shl 9)
  secp256k1FlagsBitCompression*   = (1 shl 8)


const
  secp256k1ContextVerify* = (
    secp256k1FlagsTypeContext or secp256k1FlagsBitContextVerify
  )
  secp256k1ContextSign* = (
    secp256k1FlagsTypeContext or secp256k1FlagsBitContextSign
  )
  secp256k1ContextNone* = secp256k1FlagsTypeContext


const
  secp256k1EcCompressed* = (
    secp256k1FlagsTypeCompression or secp256k1FlagsBitCompression
  )
  secp256k1EcUncompressed* = secp256k1FlagsTypeCompression


const
  secp256k1TagPubkeyEven* = 0x00000002
  secp256k1TagPubkeyOdd* = 0x00000003
  secp256k1TagPubkeyUncompressed* = 0x00000004
  secp256k1TagPubkeyHybridEven* = 0x00000006
  secp256k1TagPubkeyHybridOdd* = 0x00000007


# ## Create/Clone/Copy Procedures
# Context
proc secp256k1ContextCreate*(flags: cuint): RawSecp256k1Context {.
    cdecl,
    importc: "secp256k1_context_create",
    header: "secp256k1.h"
  .}


proc secp256k1ContextClone*(ctx: RawSecp256k1Context): RawSecp256k1Context {.
    cdecl,
    importc: "secp256k1_context_clone",
    header: "secp256k1.h"
  .}


proc secp256k1ContextDestroy*(ctx: RawSecp256k1Context) {.
    cdecl,
    importc: "secp256k1_context_destroy",
    header: "secp256k1.h"
  .}


# Scratch Space
proc secp256k1ScratchSpaceCreate*(ctx: RawSecp256k1Context; maxSize: csize): RawSecp256k1ScratchSpace {.
    cdecl,
    importc: "secp256k1_scratch_space_create",
    header: "secp256k1.h"
  .}

proc secp256k1ScratchSpaceDestroy*(scratch: RawSecp256k1ScratchSpace) {.
    cdecl,
    importc: "secp256k1_scratch_space_destroy",
    header: "secp256k1.h"
  .}


# Safe Versions
proc destroySecp256k1Context*(ctx: Secp256k1Context) =
  secp256k1ContextDestroy(ctx.raw)


proc newSecp256k1Context*(flags: cuint): Secp256k1Context =
  new(result, destroySecp256k1Context)
  result.raw = secp256k1ContextCreate(flags)


proc destroySecp256k1ScratchSpace*(scratch: Secp256k1Context) =
  secp256k1ScratchSpaceDestroy(scratch.raw)


proc newSecp256k1ScratchSpace*(ctx: Secp256k1Context; maxSize: csize): Secp256k1ScratchSpace =
  new(result, destroySecp256k1ScratchSpace)
  result.raw = secp256k1ScratchSpaceCreate(ctx.raw, maxSize)