open Types
open Values

(** The minimum/maximum values an integer type can have depending on its type *)

let i8_min = Z.of_string "-128"

let i8_max = Z.of_string "127"

let i16_min = Z.of_string "-32768"

let i16_max = Z.of_string "32767"

let i32_min = Z.of_string "-2147483648"

let i32_max = Z.of_string "2147483647"

let i64_min = Z.of_string "-9223372036854775808"

let i64_max = Z.of_string "9223372036854775807"

let i128_min = Z.of_string "-170141183460469231731687303715884105728"

let i128_max = Z.of_string "170141183460469231731687303715884105727"

let u8_min = Z.of_string "0"

let u8_max = Z.of_string "255"

let u16_min = Z.of_string "0"

let u16_max = Z.of_string "65535"

let u32_min = Z.of_string "0"

let u32_max = Z.of_string "4294967295"

let u64_min = Z.of_string "0"

let u64_max = Z.of_string "18446744073709551615"

let u128_min = Z.of_string "0"

let u128_max = Z.of_string "340282366920938463463374607431768211455"

(** Being a bit conservative about isize/usize: depending on the system,
    the values are encoded as 32-bit values or 64-bit values - we may
    want to take that into account in the future *)

let isize_min = i32_min

let isize_max = i32_max

let usize_min = u32_min

let usize_max = u32_max

(** Check that an integer value is in range *)
let check_int_in_range (int_ty : integer_type) (i : big_int) : bool =
  match int_ty with
  | Isize -> Z.leq isize_min i && Z.leq i isize_max
  | I8 -> Z.leq i8_min i && Z.leq i i8_max
  | I16 -> Z.leq i16_min i && Z.leq i i16_max
  | I32 -> Z.leq i32_min i && Z.leq i i32_max
  | I64 -> Z.leq i64_min i && Z.leq i i64_max
  | I128 -> Z.leq i128_min i && Z.leq i i128_max
  | Usize -> Z.leq usize_min i && Z.leq i usize_max
  | U8 -> Z.leq u8_min i && Z.leq i u8_max
  | U16 -> Z.leq u16_min i && Z.leq i u16_max
  | U32 -> Z.leq u32_min i && Z.leq i u32_max
  | U64 -> Z.leq u64_min i && Z.leq i u64_max
  | U128 -> Z.leq u128_min i && Z.leq i u128_max

(** Check that a scalar value is correct (the integer value it contains is in range) *)
let check_scalar_value_in_range (v : scalar_value) : bool =
  check_int_in_range v.int_ty v.value

(** Make a scalar value, while checking the value is in range *)
let mk_scalar (int_ty : integer_type) (i : big_int) :
    (scalar_value, unit) result =
  if check_int_in_range int_ty i then Ok { value = i; int_ty } else Error ()