# IfcOpenShell - IFC toolkit and geometry engine
# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
#
# This file is part of IfcOpenShell.
#
# IfcOpenShell is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# IfcOpenShell 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 Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.

from typing import Any, Union

import ifcopenshell.util.cost
import ifcopenshell.util.date
import ifcopenshell.util.element

PRODUCTIVITY_PSET_DATA = Union[dict[str, Any], None]
# https://ifc43-docs.standards.buildingsmart.org/IFC/RELEASE/IFC4x3/HTML/lexical/IfcConstructionResource.htm#Table-7.3.3.7.1.3.H
RESOURCES_TO_QUANTITIES: dict[str, tuple[str, ...]] = {
    "IfcCrewResource": ("IfcQuantityTime",),
    "IfcLaborResource": ("IfcQuantityTime",),
    "IfcSubContractResource": ("IfcQuantityTime",),
    "IfcConstructionEquipmentResource": ("IfcQuantityTime",),
    "IfcConstructionMaterialResource": (
        "IfcQuantityVolume",
        "IfcQuantityArea",
        "IfcQuantityLength",
        "IfcQuantityWeight",
    ),
    "IfcConstructionProductResource": ("IfcQuantityCount",),
}


def get_productivity(resource: ifcopenshell.entity_instance, should_inherit: bool = True) -> PRODUCTIVITY_PSET_DATA:
    productivity = ifcopenshell.util.element.get_psets(resource).get("EPset_Productivity", None)
    if should_inherit and not productivity:
        # Note: This is not part of the Schema - but it makes sense to inherit from parent
        productivity = get_parent_productivity(resource)
    return productivity


def get_parent_productivity(resource: ifcopenshell.entity_instance) -> PRODUCTIVITY_PSET_DATA:
    if not resource.Nests:
        return
    else:
        parent_resource = resource.Nests[0].RelatingObject
        productivity = ifcopenshell.util.element.get_psets(parent_resource).get("EPset_Productivity", None)
        return productivity


def get_unit_consumed(productivity: PRODUCTIVITY_PSET_DATA) -> Union[Any, None]:
    duration = productivity.get("BaseQuantityConsumed", None)
    if not duration:
        return
    return ifcopenshell.util.date.ifc2datetime(duration)


def get_quantity_produced(productivity: PRODUCTIVITY_PSET_DATA) -> float:
    if not productivity:
        return 0.0
    return productivity.get("BaseQuantityProducedValue", 0.0)


def get_quantity_produced_name(productivity: PRODUCTIVITY_PSET_DATA):
    if not productivity:
        return ""
    return productivity.get("BaseQuantityProducedName", "")


def get_total_quantity_produced(resource: ifcopenshell.entity_instance, quantity_name_in_process: str) -> float:
    def get_product_quantity(product: ifcopenshell.entity_instance, quantity_name: str):
        psets = ifcopenshell.util.element.get_psets(product)
        for pset in psets.values():
            for name, value in pset.items():
                if name == quantity_name:
                    return float(value)

    total = 0.0
    products = get_parametric_resource_products(resource)
    if quantity_name_in_process == "Count":
        total = len(products)
    else:
        for product in products:
            total += get_product_quantity(product, quantity_name_in_process) or 0
    return total


def get_parametric_resource_products(resource: ifcopenshell.entity_instance) -> list[ifcopenshell.entity_instance]:
    products = []
    for rel in resource.HasAssignments or []:
        if not rel.is_a("IfcRelAssignsToProcess"):
            continue
        for rel2 in rel.RelatingProcess.HasAssignments or []:
            if not rel2.is_a("IfcRelAssignsToProduct"):
                continue
            products.append(rel2.RelatingProduct)
    return products


def get_task_assignments(resource: ifcopenshell.entity_instance) -> Union[ifcopenshell.entity_instance, None]:
    for rel in resource.HasAssignments or []:
        if not rel.is_a("IfcRelAssignsToProcess"):
            continue
        return rel.RelatingProcess


def get_resource_required_work(resource: ifcopenshell.entity_instance) -> Union[str, None]:
    productivity = get_productivity(resource)
    if productivity:
        quantity_produced = get_quantity_produced(productivity)
        time_consumed = get_unit_consumed(productivity)
        quantity_name_in_process = get_quantity_produced_name(productivity)
        total_quantity_to_produce = get_total_quantity_produced(resource, quantity_name_in_process)
        if not time_consumed or not quantity_produced or not total_quantity_to_produce:
            return
        iso_string = ""
        if "T" in productivity.get("BaseQuantityConsumed", ""):
            seconds = (time_consumed.days * 24 * 60 * 60) + time_consumed.seconds
            productivity_ratio = seconds / quantity_produced
            required_work = total_quantity_to_produce * productivity_ratio
            iso_string = f"PT{required_work / 60 / 60}H"
        else:
            days = time_consumed.days + (time_consumed.seconds / (24 * 60 * 60))
            productivity_ratio = days / quantity_produced
            required_work = total_quantity_to_produce * productivity_ratio
            iso_string = f"P{required_work}D"
        return iso_string


def get_nested_resources(resource: ifcopenshell.entity_instance) -> list[ifcopenshell.entity_instance]:
    return [object for rel in resource.IsNestedBy or [] for object in rel.RelatedObjects]


def get_cost(resource: ifcopenshell.entity_instance) -> tuple[Union[float, None], Union[str, None]]:
    """Get cost data for IfcConstructionResource.

    :return: a tuple of cost and unit.
    """
    cost, unit = None, None
    if base_costs := resource.BaseCosts:
        costs = [ifcopenshell.util.cost.calculate_applied_value(resource, cost_value) for cost_value in base_costs]
        cost = sum(costs)
        unit_basis = next((unit_basis for cost_value in base_costs if (unit_basis := cost_value.UnitBasis)), None)
        if unit_basis and (unit_component := unit_basis.UnitComponent).is_a("IfcConversionBasedUnit"):
            unit = unit_component.Name
    return cost, unit


def get_quantity(resource: ifcopenshell.entity_instance) -> float:
    if resource.Usage and resource.Usage.ScheduleWork:
        duration = ifcopenshell.util.date.ifc2datetime(resource.Usage.ScheduleWork)
        return duration.total_seconds() / 3600
    # TODO: is it safe to assume None quantity should be treated as 1.0? See #910 in ifc4x3dev.
    quantity = resource.BaseQuantity
    return 1.0 if quantity is None else quantity[3]


def get_parent_cost(resource: ifcopenshell.entity_instance) -> Union[tuple[Union[float, None], Union[str, None]], None]:
    if not (nests := resource.Nests):
        return
    else:
        cost = get_cost(nests[0].RelatingObject)
        return cost