# Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES.  All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
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import pynini
from nemo_text_processing.text_normalization.ar.graph_utils import (
    NEMO_SPACE,
    GraphFst,
    delete_extra_space,
    insert_space,
)
from pynini.lib import pynutil


class DecimalFst(GraphFst):
    """
    Finite state transducer for classifying decimal
        e.g. "سبعة وتسعة وتسعون من مئة" -> decimal { negative: "false" integer_part: "7," fractional_part: "99" }

    Args:
        tn_decimal: Text normalization Decimal graph
    """

    def __init__(self, tn_decimal):
        super().__init__(name="decimal", kind="classify")

        optional_graph_negative = pynini.closure(
            pynutil.insert("negative: ") + pynini.cross("سالب", '"true"') + delete_extra_space, 0, 1,
        )

        graph_fractional_part = pynini.invert(tn_decimal.graph_fractional).optimize()
        graph_integer_part = pynini.invert(tn_decimal.integer_part).optimize()
        optional_graph_quantity = pynini.invert(tn_decimal.optional_quantity).optimize()
        delete_seperator = pynini.string_map([("و", "")])

        graph_fractional = (
            pynutil.insert('fractional_part: "') + delete_seperator + graph_fractional_part + pynutil.insert('"')
        )
        graph_integer = pynutil.insert('integer_part: "') + graph_integer_part + pynutil.insert('"')
        optional_graph_quantity = pynutil.insert('quantity: "') + optional_graph_quantity + pynutil.insert('"')
        optional_graph_quantity = pynini.closure(pynini.accep(NEMO_SPACE) + optional_graph_quantity, 0, 1)

        self.final_graph_wo_sign = (
            graph_integer + pynini.accep(NEMO_SPACE) + graph_fractional + optional_graph_quantity
        )
        self.final_graph_wo_negative = optional_graph_negative + self.final_graph_wo_sign

        final_graph = self.add_tokens(self.final_graph_wo_negative)
        self.fst = final_graph.optimize()
