import ifcopenshell
from ifcopenshell.util import cost as cst
import bonsai.tool as tool
import pandas as pd

def get_task_details(cost_item):
    """
    Checks if a cost item has a task relation and retrieves task details.
    
    Parameters:
        cost_item: The cost item to check.
    
    Returns:
        tuple: Task name, start date, and end date as strings, or empty strings if no task relation exists.
    """
    taskname = ""
    taskstart = ""
    taskend = ""
    
    if cost_item.Controls and cost_item.Controls[0].RelatedObjects:
        related_object = cost_item.Controls[0].RelatedObjects[0]
        if related_object.is_a("IfcTask"):
            taskname = related_object.Name
            taskstart = related_object.TaskTime.ScheduleStart[:10] if related_object.TaskTime and related_object.TaskTime.ScheduleStart else ""
            taskend = related_object.TaskTime.ScheduleFinish[:10] if related_object.TaskTime and related_object.TaskTime.ScheduleFinish else ""
    
    return taskname, taskstart, taskend

def calculate_total_value(cost_item):
    """
    Calculates the total value of a cost item by summing up all its CostValues.
    
    Parameters:
        cost_item: The cost item to process.
    
    Returns:
        float: The total value of the cost item rounded to two decimal places.
    """
    total_quantity = cst.get_total_quantity(cost_item)
    # Check for NaN or None
    if not total_quantity: # Filters out Nan and falsy values
        return ""
    
    total_value = 0.0
    if hasattr(cost_item, "CostValues") and cost_item.CostValues:
        for value in cost_item.CostValues:
            total_value += cst.calculate_applied_value(cost_item, value)
    return round(total_value, 2)

def calculate_quantity(cost_item):
    """
    Returns the quantity value of a cost item if present
    """
    total_quantity = cst.get_total_quantity(cost_item)
    if not total_quantity:
        return ""
    else:
        return total_quantity
    
def calculate_summary(cost_item):
    """
    Returns the summary of children cost items' value if present
    else the product of quantity x value
    """
    total_summary = cst.sum_child_root_elements(cost_item)
    if total_summary != 0:
        return round(total_summary,2)
    else:
        return multiply_cost_quantity(cost_item)
    
def multiply_cost_quantity(cost_item):
     """
    Returns the product of quantity x value
    """
    if calculate_total_value(cost_item) and calculate_quantity(cost_item):
        item_product = float(calculate_total_value(cost_item)) * float(calculate_quantity(cost_item))
        return item_product
    else:
        return ""

# Main script
model = tool.Ifc.get()

schedule_lst = model.by_type("IfcCostSchedule")

myschedule = schedule_lst[0]

# List all cost items in the schedule
costitems_lst = list(cst.get_schedule_cost_items(myschedule))

# Create an empty list for data
data = []

# Loop through all cost items
for c in costitems_lst:
    taskname, taskstart, taskend = get_task_details(c)
    total_value = calculate_total_value(c)
    total_quantity = calculate_quantity(c)
    total_summary = calculate_summary(c)
    
    item_data = {
        "ID": c.Identification if hasattr(c, 'Identification') else None,
        "Name": c.Name if hasattr(c, 'Name') else None,
        "TaskName": taskname,
        "Start": taskstart,
        "End": taskend,
        "TotalQty": total_quantity,
        "TotalValue": total_value,
        "TotalAmount": total_summary,
    }
    data.append(item_data)

# Create DataFrame
df = pd.DataFrame(data)
print(df.head(50))

# Export to CSV
#output_file = r"C:\Users\path\cost_items_schedule.csv"
#df.to_csv(output_file, index=False)
#print(f"Data exported to {output_file}")