app.py

import os
import io
import re
import streamlit as st

# Must be the very first Streamlit command.
st.set_page_config(layout="wide", initial_sidebar_state="collapsed")

from PIL import Image
import fitz  # PyMuPDF

from reportlab.lib.pagesizes import A4
from reportlab.platypus import SimpleDocTemplate, Paragraph, Spacer, Table, TableStyle
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib import colors
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.ttfonts import TTFont

# ---------------------------------------------------------------
# Define available NotoEmoji fonts (assumed in the base directory)
available_fonts = {
    "NotoEmoji Variable": "NotoEmoji-VariableFont_wght.ttf",
    "NotoEmoji Bold": "NotoEmoji-Bold.ttf",
    "NotoEmoji Light": "NotoEmoji-Light.ttf",
    "NotoEmoji Medium": "NotoEmoji-Medium.ttf",
    "NotoEmoji Regular": "NotoEmoji-Regular.ttf",
    "NotoEmoji SemiBold": "NotoEmoji-SemiBold.ttf"
}

# Sidebar: Font selection and size adjustment.
with st.sidebar:
    selected_font_name = st.selectbox(
        "Select NotoEmoji Font",
        options=list(available_fonts.keys())
    )
    selected_font_path = available_fonts[selected_font_name]
    
    auto_size = st.checkbox("Auto-size text", value=True)
    base_font_size = st.slider("Base Font Size (points)", min_value=6, max_value=16, value=10, step=1)
    if auto_size:
        st.info("Font size will adjust between 6-16 points based on content length, starting from your base size.")

# Register the chosen emoji font with ReportLab.
pdfmetrics.registerFont(TTFont(selected_font_name, selected_font_path))

# ---------------------------------------------------------------
# Helper function to wrap emoji characters with a font tag.
def apply_emoji_font(text, emoji_font):
    emoji_pattern = re.compile(
        r"([\U0001F300-\U0001F5FF"
        r"\U0001F600-\U0001F64F"
        r"\U0001F680-\U0001F6FF"
        r"\U0001F700-\U0001F77F"
        r"\U0001F780-\U0001F7FF"
        r"\U0001F800-\U0001F8FF"
        r"\U0001F900-\U0001F9FF"
        r"\U0001FA00-\U0001FA6F"
        r"\U0001FA70-\U0001FAFF"
        r"\u2600-\u26FF"
        r"\u2700-\u27BF]+)"
    )
    return emoji_pattern.sub(r'<font face="{}">\1</font>'.format(emoji_font), text)

# ---------------------------------------------------------------
# Default markdown content with your Deities Guide.
default_markdown = """# 🌟 Deities Guide: Mythology and Moral Lessons 🌟

## 1. 📜 Introduction
1. Purpose: Explore deities, spirits, saints, and beings with their stories and morals.  
2. Usage: Guide for learning and storytelling across traditions.  
3. Themes: Justice, faith, hubris, redemption, cosmic order.

## 2. 🛠️ Core Concepts of Divinity
1. Powers: Creation, omniscience, shapeshifting across entities.  
2. Life Cycle: Mortality, immortality, transitions (e.g., saints, avatars).  
3. Communication: Omens, visions, miracles from gods and spirits.

### 2.1. ⚡ Standard Abilities
1. Creation: Gods and spirits shape worlds (e.g., Allah, Vishnu).  
2. Influence: Saints, prophets intercede (e.g., Muhammad, Paul).  
3. Transformation: Angels, avatars shift forms (e.g., Gabriel, Krishna).  
4. Knowledge: Foresight or revelation (e.g., Holy Spirit, Brahma).  
5. Judgment: Divine authority (e.g., Yahweh, Yama).

### 2.2. ⏳ Mortality and Immortality
1. Gods: Eternal (e.g., Allah, Shiva).  
2. Spirits: Realm-bound (e.g., jinn, devas).  
3. Saints/Prophets: Mortal to divine (e.g., Moses, Rama).  
4. Beings: Limbo states (e.g., cherubim, rakshasas).  
5. Lessons: Faith, duty define transitions.

### 2.3. 🌠 Ascension and Signs
1. Paths: Birth, deeds, revelation (e.g., Jesus, Arjuna).  
2. Signs: Miracles, prophecies (e.g., Quran, Gita).  
3. Morals: Obedience, devotion shape destiny.

## 3. 🎲 Storytelling and Games
1. Portrayal: Gods, spirits, saints in narratives or RPGs.  
2. Dynamics: Clerics, imams, sadhus serve higher powers.  
3. Balance: Power vs. personality for depth.

### 3.1. 🎮 Dungeon Mastering Beings
1. Gods: Epic scope (e.g., Allah, Vishnu).  
2. Spirits: Local influence (e.g., jinn, apsaras).  
3. Saints: Moral anchors (e.g., St. Francis, Ali).

### 3.2. 🙏 Devotee Relationships
1. Clerics: Serve gods (e.g., Krishna’s priests).  
2. Mediums: Channel spirits (e.g., jinn whisperers).  
3. Faithful: Venerate saints/prophets (e.g., Fatima’s followers).

## 4. 🌐 Traditions and Legends
*(Top three figures—gods, spirits, saints, beings—with relationships and morals)*  
1. **American Indian** 🦅  
   1. Coyote, Raven, White Buffalo Woman: Trickster kin and wise mother.  
   2. Relation: Siblings and guide teach balance.  
   3. Lesson: Chaos breeds wisdom.  
2. **Arthurian** ⚔️  
   1. Merlin, Morgan le Fay, Arthur: Mentor, rival, son.  
   2. Relation: Family tests loyalty.  
   3. Lesson: Honor vs. betrayal.  
3. **Babylonian** 🏛️  
   1. Marduk, Tiamat, Ishtar: Son, mother, lover.  
   2. Relation: Kinship drives order.  
   3. Lesson: Power reshapes chaos.  
4. **Christian: Trinity** ✝️  
   1. God (Yahweh), Jesus, Holy Spirit: Father, Son, Spirit.  
   2. Relation: Divine family redeems.  
   3. Lesson: Faith restores grace.  
5. **Christian: Saints & Angels** 😇  
   1. St. Michael, Gabriel, Mary: Warrior, messenger, mother.  
   2. Relation: Heavenly kin serve God.  
   3. Lesson: Duty upholds divine will.  
6. **Celtic** 🍀  
   1. Lugh, Morrigan, Cernunnos: Son, mother, father.  
   2. Relation: Family governs cycles.  
   3. Lesson: Courage in fate.  
7. **Central American** 🌄  
   1. Quetzalcoatl, Tezcatlipoca, Huitzilopochtli: Brothers and war son.  
   2. Relation: Sibling rivalry creates.  
   3. Lesson: Sacrifice builds worlds.  
8. **Chinese** 🐉  
   1. Jade Emperor, Nuwa, Sun Wukong: Father, mother, rebel son.  
   2. Relation: Family enforces harmony.  
   3. Lesson: Duty curbs chaos.  
9. **Cthulhu** 🐙  
   1. Cthulhu, Nyarlathotep, Yog-Sothoth: Elder kin.  
   2. Relation: Cosmic trio overwhelms.  
   3. Lesson: Insignificance humbles.  
10. **Egyptian** ☥  
    1. Ra, Osiris, Isis: Father, son, mother.  
    2. Relation: Family ensures renewal.  
    3. Lesson: Justice prevails.  
11. **Finnish** ❄️  
    1. Väinämöinen, Louhi, Ukko: Son, mother, father.  
    2. Relation: Kinship tests wisdom.  
    3. Lesson: Perseverance wins.  
12. **Greek** 🏛️  
    1. Zeus, Hera, Athena: Father, mother, daughter.  
    2. Relation: Family rules with tension.  
    3. Lesson: Hubris meets wisdom.  
13. **Hindu: Trimurti** 🕉️  
    1. Brahma, Vishnu, Shiva: Creator, preserver, destroyer.  
    2. Relation: Divine trio cycles existence.  
    3. Lesson: Balance sustains life.  
14. **Hindu: Avatars & Devis** 🌺  
    1. Krishna, Rama, Durga: Sons and fierce mother.  
    2. Relation: Avatars and goddess protect dharma.  
    3. Lesson: Duty defeats evil.  
15. **Japanese** 🌸  
    1. Amaterasu, Susanoo, Tsukuyomi: Sister, brothers.  
    2. Relation: Siblings balance cosmos.  
    3. Lesson: Harmony vs. chaos.  
16. **Melnibonean** 🗡️  
    1. Arioch, Xiombarg, Elric: Lords and mortal son.  
    2. Relation: Pact binds chaos.  
    3. Lesson: Power corrupts.  
17. **Muslim: Divine & Messengers** ☪️  
    1. Allah, Muhammad, Gabriel: God, prophet, angel.  
    2. Relation: Messenger reveals divine will.  
    3. Lesson: Submission brings peace.  
18. **Muslim: Spirits & Kin** 👻  
    1. Jinn, Iblis, Khidr: Spirits and guide defy or aid.  
    2. Relation: Supernatural kin test faith.  
    3. Lesson: Obedience vs. rebellion.  
19. **Nehwon** 🏰  
    1. Death, Ningauble, Sheelba: Fateful trio.  
    2. Relation: Guides shape destiny.  
    3. Lesson: Cunning defies fate.  
20. **Nonhumans’** 🧝  
    1. Corellon, Moradin, Gruumsh: Elf, dwarf, orc fathers.  
    2. Relation: Rivals define purpose.  
    3. Lesson: Community endures.  
21. **Norse** ᚱ  
    1. Odin, Frigg, Loki: Father, mother, trickster son.  
    2. Relation: Family faces doom.  
    3. Lesson: Sacrifice costs.  
22. **Sumerian** 🗿  
    1. Enki, Inanna, Anu: Son, daughter, father.  
    2. Relation: Kin wield knowledge.  
    3. Lesson: Ambition shapes.

## 5. 📚 Appendices
1. Planes: Realms of gods, spirits, saints (e.g., Paradise, Svarga).  
2. Symbols: Rituals and artifacts of faith.  
3. Charts: Domains and duties for devotees.

### 5.1. 🌌 Planes of Existence
1. Heaven/Paradise: Christian/Muslim abode.  
2. Svarga: Hindu divine realm.  
3. Underworld: Spirits linger (e.g., Sheol, Naraka).

### 5.2. 🕍 Temple Trappings
1. Cross/Crescent: Christian/Muslim faith.  
2. Mandalas: Hindu devotion.  
3. Relics: Saints’ and prophets’ legacy.

### 5.3. 📊 Clerical Chart
1. Gods: Domains (e.g., creation, mercy).  
2. Spirits: Influence (e.g., guidance, mischief).  
3. Saints/Prophets: Virtues (e.g., justice, prophecy).
"""

# ---------------------------------------------------------------
# Process markdown into a two-column layout for a double-page spread.
def markdown_to_pdf_content(markdown_text):
    lines = markdown_text.strip().split('\n')
    pdf_content = []
    in_list_item = False
    current_item = None
    sub_items = []
    
    for line in lines:
        line = line.strip()
        if not line:
            continue
            
        if line.startswith('# '):
            # Skip the main title for now, added separately.
            pass
        elif line.startswith('## '):
            if current_item and sub_items:
                pdf_content.append([current_item, sub_items])
                sub_items = []
                current_item = None
            section = line.replace('## ', '').strip()
            pdf_content.append(f"<b>{section}</b>")
            in_list_item = False
        elif re.match(r'^\d+\.', line):
            if current_item and sub_items:
                pdf_content.append([current_item, sub_items])
                sub_items = []
            current_item = line.strip()
            in_list_item = True
        elif line.startswith('- ') and in_list_item:
            sub_items.append(line.strip())
        elif re.match(r'^\d+\.\d+\.', line):
            if current_item and sub_items:
                pdf_content.append([current_item, sub_items])
                sub_items = []
            current_item = line.strip()
            in_list_item = True
        else:
            if not in_list_item:
                pdf_content.append(line.strip())
    
    if current_item and sub_items:
        pdf_content.append([current_item, sub_items])
    
    # Split into two columns (left and right) based on line count.
    total_lines = sum(1 + len(subs) if isinstance(item, list) else 1 for item in pdf_content)
    target_lines = total_lines // 2
    left_column = []
    right_column = []
    current_lines = 0
    
    for item in pdf_content:
        line_count = 1 + (len(item[1]) if isinstance(item, list) else 0)
        if current_lines < target_lines or len(left_column) == 0:
            left_column.append(item)
            current_lines += line_count
        else:
            right_column.append(item)
    
    return left_column, right_column

# ---------------------------------------------------------------
# Create the PDF as a double-page spread.
def create_main_pdf(markdown_text, base_font_size=10, auto_size=False):
    buffer = io.BytesIO()
    # Double-page spread: Two A4 pages side-by-side (landscape).
    doc = SimpleDocTemplate(
        buffer, 
        pagesize=(A4[1] * 2, A4[0]),  # Width = 2 * A4 width, Height = A4 height
        leftMargin=36,
        rightMargin=36,
        topMargin=36,
        bottomMargin=36
    )
    
    styles = getSampleStyleSheet()
    story = []
    spacer_height = 10
    left_column, right_column = markdown_to_pdf_content(markdown_text)
    
    total_items = sum(1 + len(subs) if isinstance(item, list) else 1 for item in left_column + right_column)
    if auto_size:
        base_font_size = max(6, min(16, base_font_size * 200 / total_items))  # Scale based on user’s base size.
    
    item_font_size = base_font_size
    subitem_font_size = base_font_size * 0.9
    section_font_size = base_font_size * 1.2
    title_font_size = min(20, base_font_size * 1.5)
    
    # Define ParagraphStyles using Helvetica for normal text.
    title_style = ParagraphStyle(
        'Heading1',
        parent=styles['Heading1'],
        fontName="Helvetica-Bold",
        textColor=colors.darkblue,
        alignment=1,
        fontSize=title_font_size
    )
    
    section_style = ParagraphStyle(
        'SectionStyle',
        parent=styles['Heading2'],
        fontName="Helvetica-Bold",
        textColor=colors.darkblue,
        fontSize=section_font_size,
        leading=section_font_size * 1.2,
        spaceAfter=2
    )
    
    item_style = ParagraphStyle(
        'ItemStyle',
        parent=styles['Normal'],
        fontName="Helvetica",
        fontSize=item_font_size,
        leading=item_font_size * 1.2,
        spaceAfter=1
    )
    
    subitem_style = ParagraphStyle(
        'SubItemStyle',
        parent=styles['Normal'],
        fontName="Helvetica",
        fontSize=subitem_font_size,
        leading=subitem_font_size * 1.2,
        leftIndent=10,
        spaceAfter=1
    )
    
    # Title spanning both columns.
    story.append(Paragraph(apply_emoji_font("Deities Guide: Mythology and Moral Lessons", selected_font_name), title_style))
    story.append(Spacer(1, spacer_height))
    
    # Prepare two-column layout.
    left_cells = []
    for item in left_column:
        if isinstance(item, str) and item.startswith('<b>'):
            text = item.replace('<b>', '').replace('</b>', '')
            left_cells.append(Paragraph(apply_emoji_font(text, selected_font_name), section_style))
        elif isinstance(item, list):
            main_item, sub_items = item
            left_cells.append(Paragraph(apply_emoji_font(main_item, selected_font_name), item_style))
            for sub_item in sub_items:
                left_cells.append(Paragraph(apply_emoji_font(sub_item, selected_font_name), subitem_style))
        else:
            left_cells.append(Paragraph(apply_emoji_font(item, selected_font_name), item_style))
    
    right_cells = []
    for item in right_column:
        if isinstance(item, str) and item.startswith('<b>'):
            text = item.replace('<b>', '').replace('</b>', '')
            right_cells.append(Paragraph(apply_emoji_font(text, selected_font_name), section_style))
        elif isinstance(item, list):
            main_item, sub_items = item
            right_cells.append(Paragraph(apply_emoji_font(main_item, selected_font_name), item_style))
            for sub_item in sub_items:
                right_cells.append(Paragraph(apply_emoji_font(sub_item, selected_font_name), subitem_style))
        else:
            right_cells.append(Paragraph(apply_emoji_font(item, selected_font_name), item_style))
    
    # Balance the columns by padding with empty strings.
    max_cells = max(len(left_cells), len(right_cells))
    left_cells.extend([""] * (max_cells - len(left_cells)))
    right_cells.extend([""] * (max_cells - len(right_cells)))
    
    # Create a table for the double-page spread.
    table_data = list(zip(left_cells, right_cells))
    col_width = (A4[1] - 36)  # Half the spread width minus margins.
    table = Table(table_data, colWidths=[col_width, col_width], hAlign='CENTER')
    table.setStyle(TableStyle([
        ('VALIGN', (0, 0), (-1, -1), 'TOP'),
        ('ALIGN', (0, 0), (-1, -1), 'LEFT'),
        ('BACKGROUND', (0, 0), (-1, -1), colors.white),
        ('GRID', (0, 0), (-1, -1), 0, colors.white),
        ('LINEAFTER', (0, 0), (0, -1), 0.5, colors.grey),  # Divider between columns.
        ('LEFTPADDING', (0, 0), (-1, -1), 2),
        ('RIGHTPADDING', (0, 0), (-1, -1), 2),
        ('TOPPADDING', (0, 0), (-1, -1), 1),
        ('BOTTOMPADDING', (0, 0), (-1, -1), 1),
    ]))
    
    story.append(table)
    doc.build(story)
    buffer.seek(0)
    return buffer.getvalue()

# ---------------------------------------------------------------
# Convert PDF bytes to an image for preview using PyMuPDF.
def pdf_to_image(pdf_bytes):
    try:
        doc = fitz.open(stream=pdf_bytes, filetype="pdf")
        images = []
        for page in doc:
            pix = page.get_pixmap(matrix=fitz.Matrix(2.0, 2.0))
            img = Image.frombytes("RGB", [pix.width, pix.height], pix.samples)
            images.append(img)
        doc.close()
        return images
    except Exception as e:
        st.error(f"Failed to render PDF preview: {e}")
        return None

# ---------------------------------------------------------------
# Persist markdown content in session state.
if 'markdown_content' not in st.session_state:
    st.session_state.markdown_content = default_markdown

# ---------------------------------------------------------------
# Generate the PDF.
with st.spinner("Generating PDF..."):
    pdf_bytes = create_main_pdf(st.session_state.markdown_content, base_font_size, auto_size)

# Display PDF preview.
with st.container():
    pdf_images = pdf_to_image(pdf_bytes)
    if pdf_images:
        for i, img in enumerate(pdf_images):
            st.image(img, caption=f"Double-Page Spread", use_container_width=True)
    else:
        st.info("Download the PDF to view it locally.")

# PDF Download button.
st.download_button(
    label="Download PDF",
    data=pdf_bytes,
    file_name="deities_guide_double_page.pdf",
    mime="application/pdf"
)

# Markdown editor.
edited_markdown = st.text_area(
    "Modify the markdown content below:",
    value=st.session_state.markdown_content,
    height=300
)

# Update PDF on button click.
if st.button("Update PDF"):
    st.session_state.markdown_content = edited_markdown
    st.rerun()

# Markdown Download button.
st.download_button(
    label="Save Markdown",
    data=st.session_state.markdown_content,
    file_name="deities_guide.md",
    mime="text/markdown"
)