data/material_library.py

"""
Material Library for HVAC Load Calculator
Updated 2025-05-16: Removed mass_per_meter, added thermal_mass method, updated CSV handling.
Updated 2025-05-16: Fixed U-value calculation in Material.get_u_value.
Updated 2025-05-16: Updated MaterialCategory to Finishing Materials, Structural Materials, Sub-Structural Materials, Insulation.
Updated 2025-05-16: Fixed Construction.get_thermal_mass to use avg_specific_heat.

Developed by: Dr Majed Abuseif, Deakin University
© 2025
"""

from typing import Dict, List, Optional, Tuple
from enum import Enum
import pandas as pd
import streamlit as st
import uuid
import csv
import io

class MaterialCategory(Enum):
    FINISHING_MATERIALS = "Finishing Materials"
    STRUCTURAL_MATERIALS = "Structural Materials"
    SUB_STRUCTURAL_MATERIALS = "Sub-Structural Materials"
    INSULATION = "Insulation"

class ThermalMass(Enum):
    HIGH = "High"
    MEDIUM = "Medium"
    LOW = "Low"
    NO_MASS = "No Mass"

class Material:
    def __init__(self, name: str, category: MaterialCategory, conductivity: float, density: float,
                 specific_heat: float, default_thickness: float, embodied_carbon: float,
                 solar_absorption: float, price: float, is_library: bool = True):
        self.name = name
        self.category = category
        self.conductivity = max(0.01, conductivity)  # W/m·K
        self.density = max(1.0, density)  # kg/m³
        self.specific_heat = max(100.0, specific_heat)  # J/kg·K
        self.default_thickness = max(0.01, default_thickness)  # m
        self.embodied_carbon = max(0.0, embodied_carbon)  # kgCO₂e/kg
        self.solar_absorption = min(max(0.0, solar_absorption), 1.0)
        self.price = max(0.0, price)  # USD/m²
        self.is_library = is_library

    def get_thermal_mass(self) -> ThermalMass:
        if self.density < 100.0 or self.specific_heat < 800.0:
            return ThermalMass.NO_MASS
        elif self.density > 2000.0 and self.specific_heat > 800.0:
            return ThermalMass.HIGH
        elif 1000.0 <= self.density <= 2000.0 and 800.0 <= self.specific_heat <= 1200.0:
            return ThermalMass.MEDIUM
        else:
            return ThermalMass.LOW

    def get_u_value(self) -> float:
        return self.conductivity / self.default_thickness if self.default_thickness > 0 else 0.1

class Construction:
    def __init__(self, name: str, component_type: str, layers: List[Dict], is_library: bool = True):
        self.name = name
        self.component_type = component_type
        self.layers = layers or []
        self.is_library = is_library
        self.u_value = self.calculate_u_value()
        self.total_thickness = sum(layer["thickness"] for layer in self.layers)
        self.embodied_carbon = sum(layer["material"].embodied_carbon * layer["material"].density * layer["thickness"]
                                  for layer in self.layers)
        self.solar_absorption = max(layer["material"].solar_absorption for layer in self.layers) if self.layers else 0.6
        self.price = sum(layer["material"].price * layer["thickness"] / layer["material"].default_thickness
                         for layer in self.layers)

    def calculate_u_value(self) -> float:
        if not self.layers:
            return 0.1
        r_total = sum(layer["thickness"] / layer["material"].conductivity for layer in self.layers)
        return 1 / r_total if r_total > 0 else 0.1

    def get_thermal_mass(self) -> ThermalMass:
        if not self.layers:
            return ThermalMass.NO_MASS
        total_thickness = self.total_thickness
        if total_thickness == 0:
            return ThermalMass.NO_MASS
        avg_density = sum(layer["material"].density * layer["thickness"] for layer in self.layers) / total_thickness
        avg_specific_heat = sum(layer["material"].specific_heat * layer["thickness"] for layer in self.layers) / total_thickness
        if avg_density < 100.0 or avg_specific_heat < 800.0:
            return ThermalMass.NO_MASS
        elif avg_density > 2000.0 and avg_specific_heat > 800.0:
            return ThermalMass.HIGH
        elif 1000.0 <= avg_density <= 2000.0 and 800.0 <= avg_specific_heat <= 1200.0:
            return ThermalMass.MEDIUM
        else:
            return ThermalMass.LOW

class MaterialLibrary:
    def __init__(self):
        self.library_materials = self.initialize_materials()
        self.library_constructions = self.initialize_constructions()

    def initialize_materials(self) -> Dict[str, Material]:
        materials = [
            Material("Fiberglass Insulation", MaterialCategory.INSULATION, 0.04, 12.0, 840.0, 0.1, 0.5, 0.6, 5.0),
            Material("Concrete", MaterialCategory.STRUCTURAL_MATERIALS, 1.4, 2400.0, 900.0, 0.2, 1.5, 0.65, 20.0),
            Material("Steel", MaterialCategory.SUB_STRUCTURAL_MATERIALS, 50.0, 7800.0, 500.0, 0.003, 2.0, 0.7, 100.0),
            Material("Oak Wood", MaterialCategory.SUB_STRUCTURAL_MATERIALS, 0.15, 700.0, 2400.0, 0.05, 0.7, 0.5, 30.0),
            Material("Float Glass", MaterialCategory.INSULATION, 0.96, 2500.0, 840.0, 0.006, 1.0, 0.8, 50.0),
            Material("Clay Brick", MaterialCategory.STRUCTURAL_MATERIALS, 0.72, 1900.0, 900.0, 0.115, 1.2, 0.7, 15.0),
            Material("Gypsum Plaster", MaterialCategory.FINISHING_MATERIALS, 0.22, 1200.0, 1000.0, 0.013, 0.6, 0.4, 10.0),
            Material("Asphalt Shingle", MaterialCategory.FINISHING_MATERIALS, 0.16, 1100.0, 1000.0, 0.003, 0.8, 0.9, 8.0)
        ]
        return {mat.name: mat for mat in materials}

    def initialize_constructions(self) -> Dict[str, Construction]:
        constructions = [
            Construction("Exterior Wall", "Wall", [
                {"material": self.library_materials["Clay Brick"], "thickness": 0.115},
                {"material": self.library_materials["Fiberglass Insulation"], "thickness": 0.1},
                {"material": self.library_materials["Gypsum Plaster"], "thickness": 0.013}
            ]),
            Construction("Flat Roof", "Roof", [
                {"material": self.library_materials["Asphalt Shingle"], "thickness": 0.003},
                {"material": self.library_materials["Fiberglass Insulation"], "thickness": 0.15},
                {"material": self.library_materials["Concrete"], "thickness": 0.1}
            ]),
            Construction("Slab Floor", "Floor", [
                {"material": self.library_materials["Concrete"], "thickness": 0.1},
                {"material": self.library_materials["Fiberglass Insulation"], "thickness": 0.05}
            ])
        ]
        return {cons.name: cons for cons in constructions}

    def get_all_materials(self, project_materials: Optional[Dict[str, Material]] = None) -> List[Material]:
        materials = list(self.library_materials.values())
        if project_materials:
            materials.extend(list(project_materials.values()))
        return materials

    def add_project_material(self, material: Material, project_materials: Dict[str, Material]) -> Tuple[bool, str]:
        if len(project_materials) >= 20:
            return False, "Maximum 20 project materials allowed."
        if material.name in project_materials or material.name in self.library_materials:
            return False, f"Material name '{material.name}' already exists."
        project_materials[material.name] = material
        return True, f"Material '{material.name}' added to project materials."

    def edit_project_material(self, old_name: str, new_material: Material, project_materials: Dict[str, Material],
                             components: Dict[str, List]) -> Tuple[bool, str]:
        if old_name not in project_materials:
            return False, f"Material '{old_name}' not found in project materials."
        if new_material.name != old_name and (new_material.name in project_materials or new_material.name in self.library_materials):
            return False, f"Material name '{new_material.name}' already exists."
        for comp_list in components.values():
            for comp in comp_list:
                if comp.construction and any(layer["material"].name == old_name for layer in comp.layers):
                    comp.layers = [{"material": new_material if layer["material"].name == old_name else layer["material"],
                                    "thickness": layer["thickness"]} for layer in comp.layers]
                    comp.construction = Construction(
                        name=comp.construction.name,
                        component_type=comp.construction.component_type,
                        layers=comp.layers,
                        is_library=comp.construction.is_library
                    )
        project_materials.pop(old_name)
        project_materials[new_material.name] = new_material
        return True, f"Material '{old_name}' updated to '{new_material.name}'."

    def delete_project_material(self, name: str, project_materials: Dict[str, Material], components: Dict[str, List[Dict]]) -> Tuple[bool, str]:
        if name not in project_materials:
            return False, f"Material '{name}' not found in project materials."
        
        # Check if material is used in any project constructions
        for cons in self.project_constructions.values():
            if any(layer["material"].name == name for layer in cons.layers):
                return False, f"Cannot delete '{name}' as it is used in construction '{cons.name}'."
        
        # Check if material is used in any library constructions
        for cons in self.library_constructions.values():
            if any(layer["material"].name == name for layer in cons.layers):
                return False, f"Cannot delete '{name}' as it is used in library construction '{cons.name}'."
        
        # Check if material is used in any components
        for comp_type, comp_list in components.items():
            for comp in comp_list:
                if 'layers' in comp and any(layer["material"].name == name for layer in comp["layers"]):
                    return False, f"Cannot delete '{name}' as it is used in component '{comp['name']}' ({comp_type})."
        
        del project_materials[name]
        return True, f"Material '{name}' deleted successfully."

    def add_project_construction(self, construction: Construction, project_constructions: Dict[str, Construction]) -> Tuple[bool, str]:
        if len(project_constructions) >= 20:
            return False, "Maximum 20 project constructions allowed."
        if construction.name in project_constructions or construction.name in self.library_constructions:
            return False, f"Construction name '{construction.name}' already exists."
        project_constructions[construction.name] = construction
        return True, f"Construction '{construction.name}' added to project constructions."

    def edit_project_construction(self, old_name: str, new_construction: Construction,
                                 project_constructions: Dict[str, Construction],
                                 components: Dict[str, List]) -> Tuple[bool, str]:
        if old_name not in project_constructions:
            return False, f"Construction '{old_name}' not found in project constructions."
        if new_construction.name != old_name and (new_construction.name in project_constructions or new_construction.name in self.library_constructions):
            return False, f"Construction name '{new_construction.name}' already exists."
        for comp_list in components.values():
            for comp in comp_list:
                if comp.construction and comp.construction.name == old_name:
                    comp.construction = new_construction
                    comp.layers = new_construction.layers
                    comp.u_value = new_construction.u_value
        project_constructions.pop(old_name)
        project_constructions[new_construction.name] = new_construction
        return True, f"Construction '{old_name}' updated to '{new_construction.name}'."

    def delete_project_construction(self, name: str, project_constructions: Dict[str, Construction],
                                   components: Dict[str, List]) -> Tuple[bool, str]:
        if name not in project_constructions:
            return False, f"Construction '{name}' not found in project constructions."
        for comp_list in components.values():
            for comp in comp_list:
                if comp.construction and comp.construction.name == name:
                    return False, f"Construction '{name}' is used in component '{comp.name}'."
        project_constructions.pop(name)
        return True, f"Construction '{name}' deleted."

    def to_dataframe(self, data_type: str, project_materials: Optional[Dict[str, Material]] = None,
                     project_constructions: Optional[Dict[str, Construction]] = None,
                     only_project: bool = False) -> pd.DataFrame:
        if data_type == "materials":
            data = []
            materials = project_materials.values() if only_project else self.get_all_materials(project_materials)
            for mat in materials:
                data.append({
                    "Name": mat.name,
                    "Category": mat.category.value,
                    "Conductivity (W/m·K)": mat.conductivity,
                    "Density (kg/m³)": mat.density,
                    "Specific Heat (J/kg·K)": mat.specific_heat,
                    "Default Thickness (m)": mat.default_thickness,
                    "Embodied Carbon (kgCO₂e/kg)": mat.embodied_carbon,
                    "Solar Absorption": mat.solar_absorption,
                    "Price (USD/m²)": mat.price,
                    "Source": "Project" if not mat.is_library else "Library"
                })
            return pd.DataFrame(data)
        elif data_type == "constructions":
            data = []
            constructions = project_constructions.values() if only_project else list(self.library_constructions.values())
            if not only_project and project_constructions:
                constructions.extend(list(project_constructions.values()))
            for cons in constructions:
                layers_str = "; ".join(f"{layer['material'].name} ({layer['thickness']}m)" for layer in cons.layers)
                data.append({
                    "Name": cons.name,
                    "Component Type": cons.component_type,
                    "U-Value (W/m²·K)": cons.u_value,
                    "Total Thickness (m)": cons.total_thickness,
                    "Embodied Carbon (kgCO₂e/m²)": cons.embodied_carbon,
                    "Solar Absorption": cons.solar_absorption,
                    "Price (USD/m²)": cons.price,
                    "Layers": layers_str,
                    "Source": "Project" if not cons.is_library else "Library"
                })
            return pd.DataFrame(data)
        return pd.DataFrame()

def display_material_library_ui(self):
    """
    Display the Material Library UI.
    This function was moved from main.py to reduce code size.
    """
    import uuid
    
    st.title("Material Library")
    st.write("Manage materials and constructions based on ASHRAE 2005 Handbook of Fundamentals.")
    
    # CSS for box heights, scrolling, and visual appeal
    st.markdown("""
    <style>
    .box-container {
        border: 1px solid #e0e0e0;
        border-radius: 8px;
        padding: 10px;
        background-color: #f9f9f9;
        box-shadow: 0 2px 4px rgba(0,0,0,0.1);
        overflow-y: auto;
        scrollbar-width: thin;
    }
    .library-box {
        max-height: 250px;
    }
    .project-box {
        max-height: 250px;
    }
    .editor-box {
        min-height: 540px;
    }
    .stButton>button {
        width: 100%;
        font-size: 12px;
        padding: 5px;
    }
    </style>
    """, unsafe_allow_html=True)
    
    # Check for rerun trigger
    if st.session_state.get("rerun_pending", False):
        st.session_state.rerun_pending = False
        st.rerun()
    
    use_library_only = st.checkbox(
        "Use Library Materials and Constructions Only",
        value=st.session_state.use_library_only,
        help="Use predefined materials/constructions only."
    )
    st.session_state.use_library_only = use_library_only
    
    if not use_library_only and (st.session_state.project_materials or st.session_state.project_constructions):
        if st.button("Reset Project Materials and Constructions"):
            if st.checkbox("Confirm reset (deletes all project materials/constructions)"):
                st.session_state.project_materials = {}
                st.session_state.project_constructions = {}
                st.success("Project materials and constructions reset!")
                st.session_state.rerun_pending = True
    
    # CSV Import
    uploaded_file = st.file_uploader("Upload Materials and Constructions (CSV)", type=["csv"])
    if uploaded_file:
        try:
            content = uploaded_file.read().decode('utf-8')
            csv_reader = csv.DictReader(io.StringIO(content))
            materials_to_add = []
            constructions_to_add = []
            current_section = None
            for row in csv_reader:
                if row.get('Section') == 'Materials':
                    current_section = 'Materials'
                    materials_to_add.append(row)
                elif row.get('Section') == 'Constructions':
                    current_section = 'Constructions'
                    constructions_to_add.append(row)
                elif current_section == 'Materials':
                    materials_to_add.append(row)
                elif current_section == 'Constructions':
                    constructions_to_add.append(row)
    
            # Handle Materials
            for mat_data in materials_to_add:
                name = mat_data.get('Name', '').strip()
                if not name:
                    st.warning("Skipping material with empty name.")
                    continue
                if name in st.session_state.project_materials or name in self.material_library.library_materials:
                    st.warning(f"Material '{name}' already exists.")
                    action = st.radio(f"Action for '{name}'", ["Overwrite", "Ignore"], key=f"mat_action_{name}")
                    if action == "Ignore":
                        continue
                try:
                    category = mat_data.get('Category', 'Insulation').strip()
                    if not category or category not in [c.value for c in MaterialCategory]:
                        category = 'Insulation'
                        st.warning(f"Invalid or empty category for '{name}', defaulting to Insulation.")
                    conductivity = float(mat_data.get('Conductivity', '0.1') or '0.1')
                    density = float(mat_data.get('Density', '1000.0') or '1000.0')
                    specific_heat = float(mat_data.get('Specific Heat', '1000.0') or '1000.0')
                    default_thickness = float(mat_data.get('Default Thickness', '0.1') or '0.1')
                    embodied_carbon = float(mat_data.get('Embodied Carbon', '0.5') or '0.5')
                    solar_absorption = float(mat_data.get('Solar Absorption', '0.6') or '0.6')
                    price = float(mat_data.get('Price', '50.0') or '50.0')
                    material = Material(
                        name=name,
                        category=MaterialCategory(category),
                        conductivity=conductivity,
                        density=density,
                        specific_heat=specific_heat,
                        default_thickness=default_thickness,
                        embodied_carbon=embodied_carbon,
                        solar_absorption=solar_absorption,
                        price=price,
                        is_library=False
                    )
                    success, message = self.material_library.add_project_material(material, st.session_state.project_materials)
                    if not success:
                        st.error(message)
                except (ValueError, TypeError) as e:
                    st.error(f"Invalid data for material '{name}': {str(e)}")
    
            # Handle Constructions
            for cons_data in constructions_to_add:
                name = cons_data.get('Name', '').strip()
                if not name:
                    st.warning("Skipping construction with empty name.")
                    continue
                if name in st.session_state.project_constructions or name in self.material_library.library_constructions:
                    st.warning(f"Construction '{name}' already exists.")
                    action = st.radio(f"Action for '{name}'", ["Overwrite", "Ignore"], key=f"cons_action_{name}")
                    if action == "Ignore":
                        continue
                try:
                    layers = []
                    layer_data = cons_data.get('Layers', '').strip()
                    if layer_data:
                        for layer in layer_data.split(';'):
                            layer = layer.strip()
                            if not layer:
                                continue
                            try:
                                mat_name, thickness = layer.split(':')
                                mat_name = mat_name.strip()
                                thickness = float(thickness.strip())
                                material = (st.session_state.project_materials.get(mat_name) or
                                           self.material_library.library_materials.get(mat_name))
                                if not material:
                                    st.error(f"Material '{mat_name}' not found for construction '{name}'.")
                                    continue
                                layers.append({"material": material, "thickness": thickness})
                            except (ValueError, TypeError):
                                st.error(f"Invalid layer format in construction '{name}': {layer}")
                                continue
                    component_type = cons_data.get('Component Type', 'Wall').strip() or 'Wall'
                    construction = Construction(
                        name=name,
                        component_type=component_type,
                        layers=layers,
                        is_library=False
                    )
                    success, message = self.material_library.add_project_construction(construction, st.session_state.project_constructions)
                    if not success:
                        st.error(message)
                except (ValueError, TypeError) as e:
                    st.error(f"Invalid data for construction '{name}': {str(e)}")
            st.success("CSV import completed!")
            st.session_state.rerun_pending = True
        except Exception as e:
            st.error(f"Error importing CSV: {str(e)}")
    
    # CSV Export: Include all materials used in project constructions
    if not use_library_only and (st.session_state.project_materials or st.session_state.project_constructions):
        csv_buffer = io.StringIO()
        writer = csv.writer(csv_buffer)
        writer.writerow(['Section', 'Name', 'Category', 'Conductivity', 'Density', 'Specific Heat', 'Default Thickness',
                         'Embodied Carbon', 'Solar Absorption', 'Price', 'Is Library'])
        # Collect all materials used in project constructions
        used_materials = {}
        for cons in st.session_state.project_constructions.values():
            for layer in cons.layers:
                mat = layer["material"]
                used_materials[mat.name] = mat
        # Write project materials
        for mat in st.session_state.project_materials.values():
            used_materials[mat.name] = mat
        # Write all used materials to CSV
        for mat in used_materials.values():
            writer.writerow([
                'Materials',
                mat.name,
                mat.category.value if mat.category else '',
                mat.conductivity,
                mat.density,
                mat.specific_heat,
                mat.default_thickness,
                mat.embodied_carbon,
                mat.solar_absorption,
                mat.price,
                'True' if mat.is_library else 'False'
            ])
        writer.writerow(['Section', 'Name', 'Component Type', 'Layers'])
        for cons in st.session_state.project_constructions.values():
            layers_str = ';'.join(f"{layer['material'].name}:{layer['thickness']}" for layer in cons.layers)
            writer.writerow(['Constructions', cons.name, cons.component_type, layers_str])
        st.download_button(
            label="Download Materials and Constructions (CSV)",
            data=csv_buffer.getvalue(),
            file_name="project_materials_constructions.csv",
            mime="text/csv"
        )
    
    # Initialize session state
    if 'active_tab' not in st.session_state:
        st.session_state.active_tab = "Materials"
    if 'material_action' not in st.session_state:
        st.session_state.material_action = {"action": None, "id": None}
    if 'construction_action' not in st.session_state:
        st.session_state.construction_action = {"action": None, "id": None}
    if 'rerun_pending' not in st.session_state:
        st.session_state.rerun_pending = False
    if 'material_form_state' not in st.session_state:
        st.session_state.material_form_state = {}
    if 'construction_form_state' not in st.session_state:
        st.session_state.construction_form_state = {}
    
    # Create tabs and set active tab
    tab1, tab2 = st.tabs(["Materials", "Constructions"])
    active_tab = "Materials" if st.session_state.active_tab == "Materials" else "Constructions"
    with tab1:
        if active_tab == "Materials":
            st.session_state.active_tab = "Materials"
    with tab2:
        if active_tab == "Constructions":
            st.session_state.active_tab = "Constructions"
    
    with tab1:
        st.subheader("Materials")
        col1, col2 = st.columns([3, 2])
        with col1:
            # Category filter
            filter_options = ["All", "None"] + [c.value for c in MaterialCategory]
            category = st.selectbox("Filter by Category", filter_options, key="material_filter")
    
            st.subheader("Library Materials")
            with st.container():
                library_materials = list(self.material_library.library_materials.values())
                if category == "None":
                    library_materials = []
                elif category != "All":
                    library_materials = [m for m in library_materials if m.category.value == category]
                cols = st.columns([2, 1, 1, 1, 1])
                cols[0].write("**Name**")
                cols[1].write("**Thermal Mass**")
                cols[2].write("**U-Value (W/m²·K)**")
                cols[3].write("**Preview**")
                cols[4].write("**Copy**")
                for material in library_materials:
                    cols = st.columns([2, 1, 1, 1, 1])
                    cols[0].write(material.name)
                    cols[1].write(material.get_thermal_mass().value)
                    cols[2].write(f"{material.get_u_value():.3f}")
                    if cols[3].button("Preview", key=f"preview_lib_mat_{material.name}"):
                        if st.session_state.get("rerun_trigger") != f"preview_mat_{material.name}":
                            st.session_state.rerun_trigger = f"preview_mat_{material.name}"
                            st.session_state.material_editor = {
                                "name": material.name,
                                "category": material.category.value,
                                "conductivity": material.conductivity,
                                "density": material.density,
                                "specific_heat": material.specific_heat,
                                "default_thickness": material.default_thickness,
                                "embodied_carbon": material.embodied_carbon,
                                "solar_absorption": material.solar_absorption,
                                "price": material.price,
                                "is_edit": False
                            }
                            st.session_state.material_form_state = {
                                "name": material.name,
                                "category": material.category.value,
                                "conductivity": material.conductivity,
                                "density": material.density,
                                "specific_heat": material.specific_heat,
                                "default_thickness": material.default_thickness,
                                "embodied_carbon": material.embodied_carbon,
                                "solar_absorption": material.solar_absorption,
                                "price": material.price
                            }
                            st.session_state.active_tab = "Materials"
                    if not use_library_only and cols[4].button("Copy", key=f"copy_lib_mat_{material.name}"):
                        new_name = f"{material.name}_Project"
                        counter = 1
                        while new_name in st.session_state.project_materials or new_name in self.material_library.library_materials:
                            new_name = f"{material.name}_Project_{counter}"
                            counter += 1
                        new_material = Material(
                            name=new_name,
                            category=material.category,
                            conductivity=material.conductivity,
                            density=material.density,
                            specific_heat=material.specific_heat,
                            default_thickness=material.default_thickness,
                            embodied_carbon=material.embodied_carbon,
                            solar_absorption=material.solar_absorption,
                            price=material.price,
                            is_library=False
                        )
                        try:
                            success, message = self.material_library.add_project_material(new_material, st.session_state.project_materials)
                            if success:
                                st.success(message)
                                st.session_state.rerun_pending = True
                            else:
                                st.error(message)
                        except Exception as e:
                            st.error(f"Error copying material: {str(e)}")
    
            st.subheader("Project Materials")
            with st.container():
                if not use_library_only and st.session_state.project_materials:
                    cols = st.columns([2, 1, 1, 1, 1])
                    cols[0].write("**Name**")
                    cols[1].write("**Thermal Mass**")
                    cols[2].write("**U-Value (W/m²·K)**")
                    cols[3].write("**Edit**")
                    cols[4].write("**Delete**")
                    for material in st.session_state.project_materials.values():
                        cols = st.columns([2, 1, 1, 1, 1])
                        cols[0].write(material.name)
                        cols[1].write(material.get_thermal_mass().value)
                        cols[2].write(f"{material.get_u_value():.3f}")
                        if cols[3].button("Edit", key=f"edit_proj_mat_{material.name}"):
                            if st.session_state.get("rerun_trigger") != f"edit_mat_{material.name}":
                                st.session_state.rerun_trigger = f"edit_mat_{material.name}"
                                st.session_state.material_editor = {
                                    "name": material.name,
                                    "category": material.category.value,
                                    "conductivity": material.conductivity,
                                    "density": material.density,
                                    "specific_heat": material.specific_heat,
                                    "default_thickness": material.default_thickness,
                                    "embodied_carbon": material.embodied_carbon,
                                    "solar_absorption": material.solar_absorption,
                                    "price": material.price,
                                    "is_edit": True,
                                    "original_name": material.name
                                }
                                st.session_state.material_form_state = {
                                    "name": material.name,
                                    "category": material.category.value,
                                    "conductivity": material.conductivity,
                                    "density": material.density,
                                    "specific_heat": material.specific_heat,
                                    "default_thickness": material.default_thickness,
                                    "embodied_carbon": material.embodied_carbon,
                                    "solar_absorption": material.solar_absorption,
                                    "price": material.price
                                }
                                st.session_state.active_tab = "Materials"
                        if cols[4].button("Delete", key=f"delete_proj_mat_{material.name}"):
                            success, message = self.material_library.delete_project_material(
                                material.name, st.session_state.project_materials, st.session_state.components
                            )
                            if success:
                                st.success(message)
                                st.session_state.rerun_pending = True
                            else:
                                st.error(message)
                else:
                    st.write("No project materials added.")
    
        with col2:
            st.subheader("Material Editor/Creator")
            with st.container():
                with st.form("material_editor_form", clear_on_submit=False):
                    editor_state = st.session_state.get("material_editor", {})
                    form_state = st.session_state.get("material_form_state", {
                        "name": "",
                        "category": "Insulation",
                        "conductivity": 0.1,
                        "density": 1000.0,
                        "specific_heat": 1000.0,
                        "default_thickness": 0.1,
                        "embodied_carbon": 0.5,
                        "solar_absorption": 0.6,
                        "price": 50.0
                    })
                    is_edit = editor_state.get("is_edit", False)
                    original_name = editor_state.get("original_name", "")
                    name = st.text_input(
                        "Material Name",
                        value=form_state.get("name", editor_state.get("name", "")),
                        help="Unique material identifier",
                        key="material_name_input"
                    )
                    filter_category = st.session_state.get("material_filter", "All")
                    default_category = (filter_category if filter_category in [c.value for c in MaterialCategory]
                                      else editor_state.get("category", "Insulation"))
                    category_index = ([c.value for c in MaterialCategory].index(default_category)
                                     if default_category in [c.value for c in MaterialCategory] else 0)
                    category = st.selectbox(
                        "Category",
                        [c.value for c in MaterialCategory],
                        index=category_index,
                        help="Material type classification",
                        key="material_category_input"
                    )
                    conductivity = st.number_input(
                        "Thermal Conductivity (W/m·K)",
                        min_value=0.01,
                        value=form_state.get("conductivity", editor_state.get("conductivity", 0.1)),
                        help="Heat flow ease",
                        key="material_conductivity_input"
                    )
                    density = st.number_input(
                        "Density (kg/m³)",
                        min_value=1.0,
                        value=form_state.get("density", editor_state.get("density", 1000.0)),
                        help="Mass per volume",
                        key="material_density_input"
                    )
                    specific_heat = st.number_input(
                        "Specific Heat (J/kg·K)",
                        min_value=100.0,
                        value=form_state.get("specific_heat", editor_state.get("specific_heat", 1000.0)),
                        help="Energy to raise temperature",
                        key="material_specific_heat_input"
                    )
                    default_thickness = st.number_input(
                        "Default Thickness (m)",
                        min_value=0.01,
                        value=form_state.get("default_thickness", editor_state.get("default_thickness", 0.1)),
                        help="Standard material thickness",
                        key="material_default_thickness_input"
                    )
                    embodied_carbon = st.number_input(
                        "Embodied Carbon (kgCO₂e/kg)",
                        min_value=0.0,
                        value=form_state.get("embodied_carbon", editor_state.get("embodied_carbon", 0.5)),
                        help="Carbon footprint",
                        key="material_embodied_carbon_input"
                    )
                    solar_absorption = st.number_input(
                        "Solar Absorption",
                        min_value=0.0,
                        max_value=1.0,
                        value=form_state.get("solar_absorption", editor_state.get("solar_absorption", 0.6)),
                        help="Solar energy absorbed (0-1)",
                        key="material_solar_absorption_input"
                    )
                    price = st.number_input(
                        "Price (USD/m²)",
                        min_value=0.0,
                        value=form_state.get("price", editor_state.get("price", 50.0)),
                        help="Cost per area",
                        key="material_price_input"
                    )
    
                    # Save Material button inside form
                    if st.form_submit_button("Save Material"):
                        action_id = str(uuid.uuid4())
                        if st.session_state.material_action.get("id") != action_id:
                            st.session_state.material_action = {"action": "save", "id": action_id}
                            # Update form state
                            st.session_state.material_form_state = {
                                "name": name,
                                "category": category,
                                "conductivity": conductivity,
                                "density": density,
                                "specific_heat": specific_heat,
                                "default_thickness": default_thickness,
                                "embodied_carbon": embodied_carbon,
                                "solar_absorption": solar_absorption,
                                "price": price
                            }
                            if use_library_only:
                                st.error("Cannot add/edit materials in library-only mode.")
                            else:
                                if not name or not name.strip():
                                    st.error("Material name cannot be empty.")
                                elif (name in st.session_state.project_materials or name in self.material_library.library_materials) and (not is_edit or name != original_name):
                                    st.error(f"Material '{name}' already exists.")
                                else:
                                    try:
                                        # If editing and name changed, treat as new material
                                        save_as_new = is_edit and name != original_name
                                        new_material = Material(
                                            name=name,
                                            category=MaterialCategory(category),
                                            conductivity=conductivity,
                                            density=density,
                                            specific_heat=specific_heat,
                                            default_thickness=default_thickness,
                                            embodied_carbon=embodied_carbon,
                                            solar_absorption=solar_absorption,
                                            price=price,
                                            is_library=False
                                        )
                                        if is_edit and not save_as_new:
                                            success, message = self.material_library.edit_project_material(
                                                original_name, new_material, st.session_state.project_materials, st.session_state.components
                                            )
                                        else:
                                            success, message = self.material_library.add_project_material(new_material, st.session_state.project_materials)
                                        if success:
                                            st.success(message)
                                            st.session_state.material_editor = {}
                                            st.session_state.material_form_state = {
                                                "name": "",
                                                "category": "Insulation",
                                                "conductivity": 0.1,
                                                "density": 1000.0,
                                                "specific_heat": 1000.0,
                                                "default_thickness": 0.1,
                                                "embodied_carbon": 0.5,
                                                "solar_absorption": 0.6,
                                                "price": 50.0
                                            }
                                            st.session_state.material_action = {"action": None, "id": None}
                                            st.session_state.rerun_trigger = None
                                            st.session_state.rerun_pending = True
                                        else:
                                            st.error(f"Failed to save material: {message}")
                                    except Exception as e:
                                        st.error(f"Error saving material: {str(e)}")
    
        if not use_library_only:
            st.subheader("Project Materials")
            material_df = self.material_library.to_dataframe("materials",
                                                           project_materials=st.session_state.project_materials,
                                                           only_project=True)
            if not material_df.empty:
                st.dataframe(material_df, use_container_width=True)
            else:
                st.write("No project materials to display.")
    
    with tab2:
        st.subheader("Constructions")
        col1, col2 = st.columns([3, 2])
        with col1:
            filter_options = ["All", "Wall", "Roof", "Floor"]
            construction_filter = st.selectbox("Filter by Component Type", filter_options, key="construction_filter")
    
            st.subheader("Library Constructions")
            with st.container():
                library_constructions = list(self.material_library.library_constructions.values())
                if construction_filter != "All":
                    library_constructions = [c for c in library_constructions if c.component_type == construction_filter]
                cols = st.columns([2, 1, 1, 1, 1])
                cols[0].write("**Name**")
                cols[1].write("**Thermal Mass**")
                cols[2].write("**U-Value (W/m²·K)**")
                cols[3].write("**Preview**")
                cols[4].write("**Copy**")
                for construction in library_constructions:
                    cols = st.columns([2, 1, 1, 1, 1])
                    cols[0].write(construction.name)
                    cols[1].write(construction.get_thermal_mass().value)
                    cols[2].write(f"{construction.u_value:.3f}")
                    if cols[3].button("Preview", key=f"preview_lib_cons_{construction.name}"):
                        if st.session_state.get("rerun_trigger") != f"preview_cons_{construction.name}":
                            st.session_state.rerun_trigger = f"preview_cons_{construction.name}"
                            st.session_state.construction_editor = {
                                "name": construction.name,
                                "component_type": construction.component_type,
                                "layers": [{"material_name": layer["material"].name, "thickness": layer["thickness"]}
                                           for layer in construction.layers],
                                "is_edit": False
                            }
                            st.session_state.construction_form_state = {
                                "name": construction.name,
                                "component_type": construction.component_type,
                                "num_layers": len(construction.layers),
                                "layers": [{"material_name": layer["material"].name, "thickness": layer["thickness"]}
                                           for layer in construction.layers]
                            }
                            st.session_state.active_tab = "Constructions"
                    if not use_library_only and cols[4].button("Copy", key=f"copy_lib_cons_{construction.name}"):
                        new_name = f"{construction.name}_Project"
                        counter = 1
                        while new_name in st.session_state.project_constructions or new_name in self.material_library.library_constructions:
                            new_name = f"{construction.name}_Project_{counter}"
                            counter += 1
                        # Copy materials to project materials if they are library materials
                        new_layers = []
                        for layer in construction.layers:
                            material = layer["material"]
                            if material.is_library:
                                mat_name = f"{material.name}_Project"
                                counter = 1
                                while mat_name in st.session_state.project_materials or mat_name in self.material_library.library_materials:
                                    mat_name = f"{material.name}_Project_{counter}"
                                    counter += 1
                                new_material = Material(
                                    name=mat_name,
                                    category=material.category,
                                    conductivity=material.conductivity,
                                    density=material.density,
                                    specific_heat=material.specific_heat,
                                    default_thickness=material.default_thickness,
                                    embodied_carbon=material.embodied_carbon,
                                    solar_absorption=material.solar_absorption,
                                    price=material.price,
                                    is_library=False
                                )
                                success, message = self.material_library.add_project_material(new_material, st.session_state.project_materials)
                                if not success:
                                    st.error(f"Failed to copy material '{material.name}': {message}")
                                    break
                                material = new_material
                            new_layers.append({"material": material, "thickness": layer["thickness"]})
                        else:
                            new_construction = Construction(
                                name=new_name,
                                component_type=construction.component_type,
                                layers=new_layers,
                                is_library=False
                            )
                            success, message = self.material_library.add_project_construction(new_construction, st.session_state.project_constructions)
                            if success:
                                st.success(message)
                                st.session_state.rerun_pending = True
                            else:
                                st.error(message)
    
            st.subheader("Project Constructions")
            with st.container():
                if not use_library_only and st.session_state.project_constructions:
                    project_constructions = list(st.session_state.project_constructions.values())
                    if construction_filter != "All":
                        project_constructions = [c for c in project_constructions if c.component_type == construction_filter]
                    cols = st.columns([2, 1, 1, 1, 1])
                    cols[0].write("**Name**")
                    cols[1].write("**Thermal Mass**")
                    cols[2].write("**U-Value (W/m²·K)**")
                    cols[3].write("**Edit**")
                    cols[4].write("**Delete**")
                    for construction in project_constructions:
                        cols = st.columns([2, 1, 1, 1, 1])
                        cols[0].write(construction.name)
                        cols[1].write(construction.get_thermal_mass().value)
                        cols[2].write(f"{construction.u_value:.3f}")
                        if cols[3].button("Edit", key=f"edit_proj_cons_{construction.name}"):
                            if st.session_state.get("rerun_trigger") != f"edit_cons_{construction.name}":
                                st.session_state.rerun_trigger = f"edit_cons_{construction.name}"
                                st.session_state.construction_editor = {
                                    "name": construction.name,
                                    "component_type": construction.component_type,
                                    "layers": [{"material_name": layer["material"].name, "thickness": layer["thickness"]}
                                               for layer in construction.layers],
                                    "is_edit": True,
                                    "original_name": construction.name
                                }
                                st.session_state.construction_form_state = {
                                    "name": construction.name,
                                    "component_type": construction.component_type,
                                    "num_layers": len(construction.layers),
                                    "layers": [{"material_name": layer["material"].name, "thickness": layer["thickness"]}
                                               for layer in construction.layers]
                                }
                                st.session_state.active_tab = "Constructions"
                        if cols[4].button("Delete", key=f"delete_proj_cons_{construction.name}"):
                            success, message = self.material_library.delete_project_construction(
                                construction.name, st.session_state.project_constructions, st.session_state.components
                            )
                            if success:
                                st.success(message)
                                st.session_state.rerun_pending = True
                            else:
                                st.error(message)
                else:
                    st.write("No project constructions added.")
    
        with col2:
            st.subheader("Construction Editor/Creator")
            with st.container():
                # Check for available materials
                is_preview = st.session_state.get("rerun_trigger", "") and st.session_state.get("rerun_trigger", "").startswith("preview_cons_")
                materials = (list(self.material_library.library_materials.values()) if is_preview
                             else list(st.session_state.project_materials.values()))
                if not use_library_only:
                    materials.extend(list(self.material_library.library_materials.values()))
                
                if not materials and not is_preview:
                    st.warning("No materials available. Please add materials first.")
                else:
                    with st.form("construction_editor_form", clear_on_submit=False):
                        editor_state = st.session_state.get("construction_editor", {})
                        form_state = st.session_state.get("construction_form_state", {
                            "name": "",
                            "component_type": "Wall",
                            "num_layers": 1,
                            "layers": [{"material_name": "", "thickness": 0.1}]
                        })
                        is_edit = editor_state.get("is_edit", False)
                        original_name = editor_state.get("original_name", "")
                        name = st.text_input(
                            "Construction Name",
                            value=form_state.get("name", editor_state.get("name", "")),
                            help="Unique construction identifier",
                            key="construction_name_input"
                        )
                        filter_component = st.session_state.get("construction_filter", "All")
                        default_component = (filter_component if filter_component in ["Wall", "Roof", "Floor"]
                                           else editor_state.get("component_type", "Wall"))
                        component_type = st.selectbox(
                            "Component Type",
                            ["Wall", "Roof", "Floor"],
                            index=["Wall", "Roof", "Floor"].index(default_component),
                            help="Building element type",
                            key="construction_component_type_input"
                        )
                        
                        # Number of layers
                        num_layers = st.number_input(
                            "Number of Layers",
                            min_value=1,
                            max_value=10,
                            value=form_state.get("num_layers", len(editor_state.get("layers", [{"material_name": "", "thickness": 0.1}]))),
                            help="Number of material layers",
                            key="construction_num_layers_input"
                        )
                        
                        # Adjust layers list if number changed
                        layers = form_state.get("layers", editor_state.get("layers", [{"material_name": "", "thickness": 0.1}]))
                        if len(layers) < num_layers:
                            layers.extend([{"material_name": "", "thickness": 0.1}] * (num_layers - len(layers)))
                        elif len(layers) > num_layers:
                            layers = layers[:num_layers]
                        
                        # Layer inputs
                        st.write("Layers (from outside to inside):")
                        for i in range(num_layers):
                            col1, col2 = st.columns([3, 1])
                            with col1:
                                material_names = [m.name for m in materials]
                                default_index = 0
                                if layers[i]["material_name"] in material_names:
                                    default_index = material_names.index(layers[i]["material_name"])
                                layers[i]["material_name"] = st.selectbox(
                                    f"Layer {i+1} Material",
                                    material_names,
                                    index=default_index,
                                    key=f"construction_layer_{i}_material"
                                )
                            with col2:
                                layers[i]["thickness"] = st.number_input(
                                    f"Layer {i+1} Thickness (m)",
                                    min_value=0.001,
                                    value=float(layers[i].get("thickness", 0.1)),
                                    key=f"construction_layer_{i}_thickness"
                                )
                        
                        # Update form state with current layers
                        st.session_state.construction_form_state = {
                            "name": name,
                            "component_type": component_type,
                            "num_layers": num_layers,
                            "layers": layers
                        }
                        
                        # Save Construction button inside form
                        if st.form_submit_button("Save Construction"):
                            action_id = str(uuid.uuid4())
                            if st.session_state.construction_action.get("id") != action_id:
                                st.session_state.construction_action = {"action": "save", "id": action_id}
                                if use_library_only:
                                    st.error("Cannot add/edit constructions in library-only mode.")
                                else:
                                    if not name or not name.strip():
                                        st.error("Construction name cannot be empty.")
                                    elif (name in st.session_state.project_constructions or name in self.material_library.library_constructions) and (not is_edit or name != original_name):
                                        st.error(f"Construction '{name}' already exists.")
                                    else:
                                        try:
                                            # Convert layer material names to material objects
                                            construction_layers = []
                                            for layer in layers:
                                                material_name = layer["material_name"]
                                                thickness = layer["thickness"]
                                                material = (st.session_state.project_materials.get(material_name) or
                                                           self.material_library.library_materials.get(material_name))
                                                if not material:
                                                    st.error(f"Material '{material_name}' not found.")
                                                    break
                                                construction_layers.append({"material": material, "thickness": thickness})
                                            else:
                                                # If editing and name changed, treat as new construction
                                                save_as_new = is_edit and name != original_name
                                                new_construction = Construction(
                                                    name=name,
                                                    component_type=component_type,
                                                    layers=construction_layers,
                                                    is_library=False
                                                )
                                                if is_edit and not save_as_new:
                                                    success, message = self.material_library.edit_project_construction(
                                                        original_name, new_construction, st.session_state.project_constructions, st.session_state.components
                                                    )
                                                else:
                                                    success, message = self.material_library.add_project_construction(new_construction, st.session_state.project_constructions)
                                                if success:
                                                    st.success(message)
                                                    st.session_state.construction_editor = {}
                                                    st.session_state.construction_form_state = {
                                                        "name": "",
                                                        "component_type": "Wall",
                                                        "num_layers": 1,
                                                        "layers": [{"material_name": "", "thickness": 0.1}]
                                                    }
                                                    st.session_state.construction_action = {"action": None, "id": None}
                                                    st.session_state.rerun_trigger = None
                                                    st.session_state.rerun_pending = True
                                                else:
                                                    st.error(f"Failed to save construction: {message}")
                                        except Exception as e:
                                            st.error(f"Error saving construction: {str(e)}")
    
        if not use_library_only:
            st.subheader("Project Constructions")
            construction_df = self.material_library.to_dataframe("constructions",
                                                               project_constructions=st.session_state.project_constructions,
                                                               only_project=True)
            if not construction_df.empty:
                st.dataframe(construction_df, use_container_width=True)
            else:
                st.write("No project constructions to display.")
    
    # Brief help instructions
    with st.expander("Help"):
        st.markdown("""
        ### Material Library Help
        
        This section allows you to manage materials and constructions for your building components.
        
        **Materials:**
        - **Library Materials**: Pre-defined materials based on ASHRAE standards
        - **Project Materials**: Custom materials you create for your project
        - **Material Editor**: Create new materials or edit existing ones
        
        **Constructions:**
        - **Library Constructions**: Pre-defined construction assemblies
        - **Project Constructions**: Custom constructions you create
        - **Construction Editor**: Create multi-layer constructions from materials
        
        **Tips:**
        - Use the filter options to find materials by category
        - Click "Preview" to view material properties without editing
        - Click "Copy" to create a project copy of a library material/construction
        - Materials must be created before they can be used in constructions
        - Constructions must be created before they can be assigned to building components
        """)
    
    col1, col2 = st.columns(2)
    with col1:
        st.button("Back to Climate Data and Design Requirements", key="material_library_back_to_climate",
                  on_click=lambda: setattr(st.session_state, "page", "Climate Data and Design Requirements"))
    with col2:
        st.button("Continue to Building Components", key="material_library_to_building_components",
                  on_click=lambda: setattr(st.session_state, "page", "Building Components"))