import io
import re
import os
import glob
import asyncio
import hashlib
import unicodedata
import streamlit as st
from PIL import Image
import fitz
import edge_tts
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
from datetime import datetime
import pytz

st.set_page_config(layout="wide", initial_sidebar_state="collapsed")

def get_timestamp_prefix():
    central = pytz.timezone("US/Central")
    now = datetime.now(central)
    # Format: three-letter day, MMDD, HHmm + AM/PM (all uppercase)
    return now.strftime("%a %m%d %I%M%p").upper()

async def generate_audio(text, voice, filename):
    communicate = edge_tts.Communicate(text, voice)
    await communicate.save(filename)
    return filename

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]+)"
    )
    def replace_emoji(match):
        emoji = match.group(1)
        emoji = unicodedata.normalize('NFC', emoji)
        return f'<font face="{emoji_font}">{emoji}</font>'
    segments = []
    last_pos = 0
    for match in emoji_pattern.finditer(text):
        start, end = match.span()
        if last_pos < start:
            segments.append(f'<font face="DejaVuSans">{text[last_pos:start]}</font>')
        segments.append(replace_emoji(match))
        last_pos = end
    if last_pos < len(text):
        segments.append(f'<font face="DejaVuSans">{text[last_pos:]}</font>')
    return ''.join(segments)

def markdown_to_pdf_content(markdown_text, render_with_bold, auto_bold_numbers):
    lines = markdown_text.strip().split('\n')
    pdf_content = []
    number_pattern = re.compile(r'^\d+\.\s')
    for line in lines:
        line = line.strip()
        if not line or line.startswith('# '):
            continue
        if render_with_bold:
            line = re.sub(r'\*\*(.*?)\*\*', r'<b>\1</b>', line)
        if auto_bold_numbers and number_pattern.match(line):
            if not (line.startswith("<b>") and line.endswith("</b>")):
                line = f"<b>{line}</b>"
        pdf_content.append(line)
    total_lines = len(pdf_content)
    return pdf_content, total_lines

def create_pdf(markdown_text, base_font_size, render_with_bold, auto_bold_numbers, enlarge_numbered, num_columns):
    buffer = io.BytesIO()
    page_width = A4[0] * 2
    page_height = A4[1]
    doc = SimpleDocTemplate(buffer, pagesize=(page_width, page_height), leftMargin=36, rightMargin=36, topMargin=36, bottomMargin=36)
    styles = getSampleStyleSheet()
    spacer_height = 10
    pdf_content, total_lines = markdown_to_pdf_content(markdown_text, render_with_bold, auto_bold_numbers)
    item_style = ParagraphStyle(
        'ItemStyle', parent=styles['Normal'], fontName="DejaVuSans",
        fontSize=base_font_size, leading=base_font_size * 1.15, spaceAfter=1
    )
    bold_style = ParagraphStyle(
        'BoldStyle', parent=styles['Normal'], fontName="NotoEmoji-Bold",
        fontSize=base_font_size, leading=base_font_size * 1.15, spaceAfter=1
    )
    numbered_bold_style = ParagraphStyle(
        'NumberedBoldStyle', parent=styles['Normal'], fontName="NotoEmoji-Bold",
        fontSize=base_font_size + 1 if enlarge_numbered else base_font_size,
        leading=(base_font_size + 1) * 1.15 if enlarge_numbered else base_font_size * 1.15, spaceAfter=1
    )
    section_style = ParagraphStyle(
        'SectionStyle', parent=styles['Heading2'], fontName="DejaVuSans",
        textColor=colors.darkblue, fontSize=base_font_size * 1.1, leading=base_font_size * 1.32, spaceAfter=2
    )
    try:
        available_font_files = glob.glob("*.ttf")
        if not available_font_files:
            st.error("No .ttf font files found in the current directory.")
            return
        selected_font_path = None
        for f in available_font_files:
            if "NotoEmoji-Bold" in f:
                selected_font_path = f
                break
        if selected_font_path:
            pdfmetrics.registerFont(TTFont("NotoEmoji-Bold", selected_font_path))
        pdfmetrics.registerFont(TTFont("DejaVuSans", "DejaVuSans.ttf"))
    except Exception as e:
        st.error(f"Font registration error: {e}")
        return
    columns = [[] for _ in range(num_columns)]
    lines_per_column = total_lines / num_columns if num_columns > 0 else total_lines
    current_line_count = 0
    current_column = 0
    number_pattern = re.compile(r'^\d+\.\s')
    for item in pdf_content:
        if current_line_count >= lines_per_column and current_column < num_columns - 1:
            current_column += 1
            current_line_count = 0
        columns[current_column].append(item)
        current_line_count += 1
    column_cells = [[] for _ in range(num_columns)]
    for col_idx, column in enumerate(columns):
        for item in column:
            if isinstance(item, str) and item.startswith("<b>") and item.endswith("</b>"):
                content = item[3:-4].strip()
                if number_pattern.match(content):
                    column_cells[col_idx].append(Paragraph(apply_emoji_font(content, "NotoEmoji-Bold"), numbered_bold_style))
                else:
                    column_cells[col_idx].append(Paragraph(apply_emoji_font(content, "NotoEmoji-Bold"), section_style))
            else:
                column_cells[col_idx].append(Paragraph(apply_emoji_font(item, "DejaVuSans"), item_style))
    max_cells = max(len(cells) for cells in column_cells) if column_cells else 0
    for cells in column_cells:
        cells.extend([Paragraph("", item_style)] * (max_cells - len(cells)))
    col_width = (page_width - 72) / num_columns if num_columns > 0 else page_width - 72
    table_data = list(zip(*column_cells)) if column_cells else [[]]
    table = Table(table_data, colWidths=[col_width] * num_columns, 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), (num_columns-1, -1), 0.5, colors.grey),
        ('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 = [Spacer(1, spacer_height), table]
    doc.build(story)
    buffer.seek(0)
    return buffer.getvalue()

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

# -- Markdown File Selection --
md_files = [f for f in glob.glob("*.md") if os.path.basename(f) != "README.md"]
md_options = [os.path.splitext(os.path.basename(f))[0] for f in md_files]

with st.sidebar:
    st.markdown("### PDF Options")
    if md_options:
        selected_md = st.selectbox("Select Markdown File", options=md_options, index=0)
        with open(f"{selected_md}.md", "r", encoding="utf-8") as f:
            st.session_state.markdown_content = f.read()
    else:
        st.warning("No markdown file found. Please add one to your folder.")
        selected_md = None
        st.session_state.markdown_content = ""

    available_font_files = {os.path.splitext(os.path.basename(f))[0]: f for f in glob.glob("*.ttf")}
    selected_font_name = st.selectbox("Select Emoji Font", options=list(available_font_files.keys()), 
                                      index=list(available_font_files.keys()).index("NotoEmoji-Bold") if "NotoEmoji-Bold" in available_font_files else 0)
    base_font_size = st.slider("Font Size (points)", min_value=6, max_value=16, value=8, step=1)
    render_with_bold = st.checkbox("Render with Bold Formatting (remove ** markers)", value=True, key="render_with_bold")
    auto_bold_numbers = st.checkbox("Auto Bold Numbered Lines", value=True, key="auto_bold_numbers")
    enlarge_numbered = st.checkbox("Enlarge Font Size for Numbered Lines", value=True, key="enlarge_numbered")
    num_columns = st.selectbox("Number of Columns", options=[1, 2, 3, 4, 5, 6], index=3)

    # Use the file's content for editing
    edited_markdown = st.text_area("Modify the markdown content below:", value=st.session_state.markdown_content, height=300, key=f"markdown_{selected_md}_{selected_font_name}_{num_columns}")
    if st.button("Update PDF"):
        st.session_state.markdown_content = edited_markdown
        if selected_md:
            with open(f"{selected_md}.md", "w", encoding="utf-8") as f:
                f.write(edited_markdown)
        st.experimental_rerun()

    # Create a timestamp prefix for file naming
    prefix = get_timestamp_prefix()

    # Download button for Markdown with new naming convention
    st.download_button(
        label="Save Markdown",
        data=st.session_state.markdown_content,
        file_name=f"{prefix} {selected_md}.md" if selected_md else f"{prefix} default.md",
        mime="text/markdown"
    )

    st.markdown("### Text-to-Speech")
    VOICES = ["en-US-AriaNeural", "en-US-JennyNeural", "en-GB-SoniaNeural", "en-US-GuyNeural", "en-US-AnaNeural"]
    selected_voice = st.selectbox("Select Voice for TTS", options=VOICES, index=0)
    if st.button("Generate Audio"):
        # Create a filename for the audio file using the timestamp, markdown name, and selected voice
        audio_filename = f"{prefix} {selected_md} {selected_voice}.mp3" if selected_md else f"{prefix} default {selected_voice}.mp3"
        audio_file = asyncio.run(generate_audio(st.session_state.markdown_content, selected_voice, audio_filename))
        st.audio(audio_file)
        with open(audio_file, "rb") as f:
            audio_bytes = f.read()
        st.download_button("Download Audio", data=audio_bytes, file_name=audio_filename, mime="audio/mpeg")

with st.spinner("Generating PDF..."):
    pdf_bytes = create_pdf(st.session_state.markdown_content, base_font_size, render_with_bold, auto_bold_numbers, enlarge_numbered, num_columns)

with st.container():
    pdf_images = pdf_to_image(pdf_bytes)
    if pdf_images:
        for img in pdf_images:
            st.image(img, use_container_width=True)
    else:
        st.info("Download the PDF to view it locally.")

# Download button for PDF with new naming convention
with st.sidebar:
    st.download_button(
        label="Download PDF",
        data=pdf_bytes,
        file_name=f"{prefix} {selected_md}.pdf" if selected_md else f"{prefix} output.pdf",
        mime="application/pdf"
    )