"""Generate the downloadable Word report."""
import io, tempfile
from docx import Document
from docx.shared import Inches
import streamlit as st
from config import FREQUENCIES
from helpers import calc_abs_area

def generate_docx() -> bytes:
    doc = Document()
    doc.add_heading("Room Acoustics Analysis Report", 0)

    # 1 ─ Input data
    doc.add_heading("1  Input Data", 1)
    doc.add_paragraph(f"Room volume: {st.session_state.room_volume:.2f} m³")

    if st.session_state.df_current_rt is not None:
        doc.add_heading("Current Reverberation Time", 2)
        doc.add_paragraph(st.session_state.df_current_rt.to_string(index=False))

    if st.session_state.df_existing_mat is not None:
        doc.add_heading("Existing Materials – Coefficients & Areas", 2)
        doc.add_paragraph(st.session_state.df_existing_mat.to_string(index=False))

    if not st.session_state.df_background_noise.empty:
        doc.add_heading("Background-Noise Measurements", 2)
        doc.add_paragraph(st.session_state.df_background_noise.to_string(index=False))

    if st.session_state.df_spl is not None:
        doc.add_heading("Sound-Pressure Levels (SPL)", 2)
        doc.add_paragraph(st.session_state.df_spl.to_string())

    # 2 ─ Speech-intelligibility (Dots & AI)
    doc.add_heading("2  Speech-Intelligibility (Dots & AI)", 1)

    if st.session_state.dots_init_dict:
        doc.add_heading("Initial Compliance Check", 2)
        for loc, dots in st.session_state.dots_init_dict.items():
            ai, interp = st.session_state.ai_init_dict.get(loc, (None, ""))
            line = f"{loc}: Dots = {dots}"
            if ai is not None:
                line += f"  →  AI = {ai:.2f} ({interp})"
            doc.add_paragraph(line)

    if st.session_state.dots_final_dict:
        doc.add_heading("Final Compliance Check", 2)
        for loc, dots in st.session_state.dots_final_dict.items():
            ai, interp = st.session_state.ai_final_dict.get(loc, (None, ""))
            line = f"{loc}: Dots = {dots}"
            if ai is not None:
                line += f"  →  AI = {ai:.2f} ({interp})"
            doc.add_paragraph(line)

    # 3 ─ Figures
    doc.add_heading("3  Figures", 1)

    def _add(fig, caption):
        if fig is None: return
        with tempfile.NamedTemporaryFile(suffix=".png", delete=False) as tmp:
            fig.write_image(tmp.name, scale=4)
            doc.add_picture(tmp.name, width=Inches(6))
            doc.paragraphs[-1].alignment = 1
            doc.add_paragraph(caption, style="Caption")

    _add(st.session_state.fig_rt_initial, "Fig 1  Initial RT60 vs Standard Range")
    _add(st.session_state.fig_bn_initial, "Fig 2  Initial Background-Noise vs Standard Range")
    _add(st.session_state.fig_rt_final,   "Fig 3  Final RT60 vs Standard Range")
    _add(st.session_state.fig_bn_final,   "Fig 4  Final Background-Noise vs Standard Range")

    buf = io.BytesIO()
    doc.save(buf)
    return buf.getvalue()