#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You 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
# limitations under the License.
#

from typing import Optional

header = """#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You 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
# limitations under the License.
#"""

# Code generator for shared params (shared.py). Run under this folder with:
# python _shared_params_code_gen.py > shared.py

_type_for_type_converter = {
    "TypeConverters.toBoolean": "bool",
    "TypeConverters.toFloat": "float",
    "TypeConverters.toInt": "int",
    "TypeConverters.toListFloat": "List[float]",
    "TypeConverters.toListString": "List[str]",
    "TypeConverters.toString": "str",
}


def _gen_param_header(
    name: str, doc: str, defaultValueStr: Optional[str], typeConverter: str, paramType: str
) -> str:
    """
    Generates the header part for shared variables

    :param name: param name
    :param doc: param doc
    """
    Name = f"Has{name[0].upper()}{name[1:]}"

    template = f'''class {Name}(Params):
    """
    Mixin for param {name}: {doc}
    """

    {name}: "Param[{paramType}]" = Param(
        Params._dummy(),
        "{name}",
        "{doc}",
        typeConverter={typeConverter},
    )

    def __init__(self) -> None:
        super({Name}, self).__init__()'''

    if defaultValueStr is not None:
        template += f"""
        self._setDefault({name}={defaultValueStr})"""

    return template


def _gen_param_code(name: str, paramType: str) -> str:
    """
    Generates Python code for a shared param class.

    :param name: param name
    :param doc: param doc
    :param defaultValueStr: string representation of the default value
    :return: code string
    """
    # TODO: How to correctly inherit instance attributes?
    return f'''
    def get{name[0].upper()}{name[1:]}(self) -> {paramType}:
        """
        Gets the value of {name} or its default value.
        """
        return self.getOrDefault(self.{name})'''


if __name__ == "__main__":
    print(header)
    print("\n# DO NOT MODIFY THIS FILE! It was generated by _shared_params_code_gen.py.\n")
    print("from typing import List\n")
    print("from pyspark.ml.param import Param, Params, TypeConverters\n\n")
    shared = [
        (
            "maxIter",
            "max number of iterations (>= 0).",
            None,
            "TypeConverters.toInt",
        ),
        (
            "regParam",
            "regularization parameter (>= 0).",
            None,
            "TypeConverters.toFloat",
        ),
        (
            "featuresCol",
            "features column name.",
            '"features"',
            "TypeConverters.toString",
        ),
        (
            "labelCol",
            "label column name.",
            '"label"',
            "TypeConverters.toString",
        ),
        (
            "predictionCol",
            "prediction column name.",
            '"prediction"',
            "TypeConverters.toString",
        ),
        (
            "probabilityCol",
            "Column name for predicted class conditional probabilities. "
            + "Note: Not all models output well-calibrated probability estimates! "
            + "These probabilities should be treated as confidences, not precise probabilities.",
            '"probability"',
            "TypeConverters.toString",
        ),
        (
            "rawPredictionCol",
            "raw prediction (a.k.a. confidence) column name.",
            '"rawPrediction"',
            "TypeConverters.toString",
        ),
        (
            "inputCol",
            "input column name.",
            None,
            "TypeConverters.toString",
        ),
        (
            "inputCols",
            "input column names.",
            None,
            "TypeConverters.toListString",
        ),
        (
            "outputCol",
            "output column name.",
            'self.uid + "__output"',
            "TypeConverters.toString",
        ),
        (
            "outputCols",
            "output column names.",
            None,
            "TypeConverters.toListString",
        ),
        (
            "numFeatures",
            "Number of features. Should be greater than 0.",
            "262144",
            "TypeConverters.toInt",
        ),
        (
            "checkpointInterval",
            "set checkpoint interval (>= 1) or disable checkpoint (-1). "
            + "E.g. 10 means that the cache will get checkpointed every 10 iterations. Note: "
            + "this setting will be ignored if the checkpoint directory is not set in "
            + "the SparkContext.",
            None,
            "TypeConverters.toInt",
        ),
        (
            "seed",
            "random seed.",
            "hash(type(self).__name__)",
            "TypeConverters.toInt",
        ),
        (
            "tol",
            "the convergence tolerance for iterative algorithms (>= 0).",
            None,
            "TypeConverters.toFloat",
        ),
        (
            "relativeError",
            "the relative target precision for the approximate quantile "
            + "algorithm. Must be in the range [0, 1]",
            "0.001",
            "TypeConverters.toFloat",
        ),
        (
            "stepSize",
            "Step size to be used for each iteration of optimization (>= 0).",
            None,
            "TypeConverters.toFloat",
        ),
        (
            "handleInvalid",
            "how to handle invalid entries. Options are skip (which will filter "
            + "out rows with bad values), or error (which will throw an error). "
            + "More options may be added later.",
            None,
            "TypeConverters.toString",
        ),
        (
            "elasticNetParam",
            "the ElasticNet mixing parameter, in range [0, 1]. For alpha = 0, "
            + "the penalty is an L2 penalty. For alpha = 1, it is an L1 penalty.",
            "0.0",
            "TypeConverters.toFloat",
        ),
        (
            "fitIntercept",
            "whether to fit an intercept term.",
            "True",
            "TypeConverters.toBoolean",
        ),
        (
            "standardization",
            "whether to standardize the training features before fitting the " + "model.",
            "True",
            "TypeConverters.toBoolean",
        ),
        (
            "thresholds",
            "Thresholds in multi-class classification to adjust the probability of "
            + "predicting each class. Array must have length equal to the number of classes, with "
            + "values > 0, excepting that at most one value may be 0. "
            + "The class with largest value p/t is predicted, where p is the original "
            + "probability of that class and t is the class's threshold.",
            None,
            "TypeConverters.toListFloat",
        ),
        (
            "threshold",
            "threshold in binary classification prediction, in range [0, 1]",
            "0.5",
            "TypeConverters.toFloat",
        ),
        (
            "weightCol",
            "weight column name. If this is not set or empty, we treat "
            + "all instance weights as 1.0.",
            None,
            "TypeConverters.toString",
        ),
        (
            "solver",
            "the solver algorithm for optimization. If this is not set or empty, "
            + "default value is 'auto'.",
            '"auto"',
            "TypeConverters.toString",
        ),
        (
            "varianceCol",
            "column name for the biased sample variance of prediction.",
            None,
            "TypeConverters.toString",
        ),
        (
            "aggregationDepth",
            "suggested depth for treeAggregate (>= 2).",
            "2",
            "TypeConverters.toInt",
        ),
        (
            "parallelism",
            "the number of threads to use when running parallel algorithms (>= 1).",
            "1",
            "TypeConverters.toInt",
        ),
        (
            "collectSubModels",
            "Param for whether to collect a list of sub-models trained during "
            + "tuning. If set to false, then only the single best sub-model will be available "
            + "after fitting. If set to true, then all sub-models will be available. Warning: "
            + "For large models, collecting all sub-models can cause OOMs on the Spark driver.",
            "False",
            "TypeConverters.toBoolean",
        ),
        (
            "loss",
            "the loss function to be optimized.",
            None,
            "TypeConverters.toString",
        ),
        (
            "distanceMeasure",
            "the distance measure. Supported options: 'euclidean' and 'cosine'.",
            '"euclidean"',
            "TypeConverters.toString",
        ),
        (
            "validationIndicatorCol",
            "name of the column that indicates whether each row is for "
            + "training or for validation. False indicates training; true indicates validation.",
            None,
            "TypeConverters.toString",
        ),
        (
            "blockSize",
            "block size for stacking input data in matrices. Data is stacked within "
            "partitions. If block size is more than remaining data in a partition then it is "
            "adjusted to the size of this data.",
            None,
            "TypeConverters.toInt",
        ),
        (
            "maxBlockSizeInMB",
            "maximum memory in MB for stacking input data into blocks. Data is "
            + "stacked within partitions. If more than remaining data size in a partition then it "
            + "is adjusted to the data size. Default 0.0 represents choosing optimal value, "
            + "depends on specific algorithm. Must be >= 0.",
            "0.0",
            "TypeConverters.toFloat",
        ),
    ]

    code = []
    for name, doc, defaultValueStr, typeConverter in shared:
        paramType = _type_for_type_converter.get(typeConverter, "None")

        param_code = _gen_param_header(name, doc, defaultValueStr, typeConverter, paramType)
        code.append(param_code + "\n" + _gen_param_code(name, paramType))

    print("\n\n\n".join(code))
