'''
    This file is part of PM4Py (More Info: https://pm4py.fit.fraunhofer.de).

    PM4Py is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    PM4Py is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with PM4Py.  If not, see <https://www.gnu.org/licenses/>.
'''

from enum import Enum
from typing import Optional, Dict, Any
from pm4py.util import exec_utils


class Parameters(Enum):
    INCLUDE_HEADER = "include_header"


def get_model_description():
    description = """
The Log Skeleton process model contains the following declarative constraints:
- Equivalence (if the first activity occurs, then it has the same occurrences as the second one)
- Always Before (if the first activity occur, then the second activity should have been executed previously)
- Always After (if the first activity occur, then the second activity is executed in one of the following events)
- Never Together (the two activities cannot co-exist inside the same case)
- Activity Occurrences (bounds the number of occurrences for an activity in a case)
- Directly-Follows Constraints (if the first activity occurs, then the second activity shall occur immediately after)
    """
    return description


def get_model_implementation():
    implementation = "The Log Skeleton is expressed as a Python dictionary containing the keys: 'equivalence', 'always_before', 'always_after', 'never_together', 'activ_freq', 'directly_follows'.\n"
    implementation += "The values associated to 'equivalence', 'always_before', 'always_after', 'never_together', 'directly_follows' are sets containing the couples of activities satisfying the constraints.\n"
    implementation += "The value associated to 'activ_freq' is a dictionary whose keys are the activities, and the values are the allowed number of occurrences for the given activity. For example, {'A': {0, 1}, 'B': {1, 2}} tells that A could occur 0 or 1 time inside a case, while B could occur 1 or 2 times.\n"

    return implementation


def apply(lsk: Dict[str, Any], parameters: Optional[Dict[Any, Any]] = None) -> str:
    if parameters is None:
        parameters = {}

    include_header = exec_utils.get_param_value(Parameters.INCLUDE_HEADER, parameters, True)

    ret = ["\n"]

    if include_header:
        ret.append(get_model_description())
        ret.append("\n\n")
        ret.append("I have a Log Skeleton process model containing the following declarative constraints:\n\n")

    # equivalence
    ret.append("Equivalence: ")
    for constr in lsk["equivalence"]:
        ret.append(" " + str(constr))
    ret.append("\n\n")

    # always before
    ret.append("Always Before: ")
    for constr in lsk["always_before"]:
        ret.append(" " + str(constr))
    ret.append("\n\n")

    # always after
    ret.append("Always After: ")
    for constr in lsk["always_after"]:
        ret.append(" " + str(constr))
    ret.append("\n\n")

    # never together
    ret.append("Never Together: ")
    for constr in lsk["never_together"]:
        ret.append(" " + str(constr))
    ret.append("\n\n")

    # activity occurrences
    ret.append("Activity Occurrences: ")
    for constr, occs in lsk["activ_freq"].items():
        ret.append(" " + str(constr) + ": " + ", ".join(sorted([str(x) for x in occs])) + ";")
    ret.append("\n\n")

    # directly-follows
    ret.append("Directly-Follows Constraints: ")
    for constr in lsk["directly_follows"]:
        ret.append(" "+str(constr))
    ret.append("\n\n")

    return "".join(ret)