"""Primitive tuple ops for *variable-length* tuples.

Note: Varying-length tuples are represented as boxed Python tuple
objects, i.e. tuple_rprimitive (RPrimitive), not RTuple.
"""

from mypyc.ir.ops import ERR_MAGIC, ERR_FALSE
from mypyc.ir.rtypes import (
    tuple_rprimitive, int_rprimitive, list_rprimitive, object_rprimitive,
    c_pyssize_t_rprimitive, bit_rprimitive
)
from mypyc.primitives.registry import method_op, function_op, custom_op


# tuple[index] (for an int index)
tuple_get_item_op = method_op(
    name='__getitem__',
    arg_types=[tuple_rprimitive, int_rprimitive],
    return_type=object_rprimitive,
    c_function_name='CPySequenceTuple_GetItem',
    error_kind=ERR_MAGIC)

# Construct a boxed tuple from items: (item1, item2, ...)
new_tuple_op = custom_op(
    arg_types=[c_pyssize_t_rprimitive],
    return_type=tuple_rprimitive,
    c_function_name='PyTuple_Pack',
    error_kind=ERR_MAGIC,
    var_arg_type=object_rprimitive)

new_tuple_with_length_op = custom_op(
    arg_types=[c_pyssize_t_rprimitive],
    return_type=tuple_rprimitive,
    c_function_name='PyTuple_New',
    error_kind=ERR_MAGIC)

# PyTuple_SET_ITEM does no error checking,
# and should only be used to fill in brand new tuples.
new_tuple_set_item_op = custom_op(
    arg_types=[tuple_rprimitive, int_rprimitive, object_rprimitive],
    return_type=bit_rprimitive,
    c_function_name='CPySequenceTuple_SetItemUnsafe',
    error_kind=ERR_FALSE,
    steals=[False, False, True])

# Construct tuple from a list.
list_tuple_op = function_op(
    name='builtins.tuple',
    arg_types=[list_rprimitive],
    return_type=tuple_rprimitive,
    c_function_name='PyList_AsTuple',
    error_kind=ERR_MAGIC,
    priority=2)

# Construct tuple from an arbitrary (iterable) object.
function_op(
    name='builtins.tuple',
    arg_types=[object_rprimitive],
    return_type=tuple_rprimitive,
    c_function_name='PySequence_Tuple',
    error_kind=ERR_MAGIC)

# tuple[begin:end]
tuple_slice_op = custom_op(
    arg_types=[tuple_rprimitive, int_rprimitive, int_rprimitive],
    return_type=object_rprimitive,
    c_function_name='CPySequenceTuple_GetSlice',
    error_kind=ERR_MAGIC)