from reportlab.platypus import Frame, NextPageTemplate, PageTemplate, BaseDocTemplate, Paragraph, Image, Spacer,Paragraph
from reportlab.lib.units import cm
from reportlab.lib.styles import ParagraphStyle, getSampleStyleSheet
from reportlab.lib.enums import TA_JUSTIFY
from reportlab.lib.pagesizes import letter
from reportlab.lib import colors
from datetime import datetime

def generate_pdf_report(disease_info, filename="report.pdf")->None:
    """Generates a scientific article-style PDF report with two-column layout and a logo."""

    # Custom styles
    styles = getSampleStyleSheet()

    # Add custom styles
    styles.add(ParagraphStyle(
        name='TitleStyle',
        parent=styles['Heading1'],
        fontSize=16,
        leading=20,
        alignment=1,  # Center
        spaceAfter=20,
        textColor=colors.darkblue
    ))

    styles.add(ParagraphStyle(
        name='AuthorStyle',
        parent=styles['Heading3'],
        fontSize=10,
        leading=12,
        alignment=1,
        spaceAfter=20,
        textColor=colors.darkgrey
    ))

    styles.add(ParagraphStyle(
        name='AbstractStyle',
        parent=styles['BodyText'],
        fontSize=10,
        leading=12,
        alignment=TA_JUSTIFY,
        backColor=colors.lightgrey,
        borderPadding=5,
        spaceAfter=20
    ))

    styles.add(ParagraphStyle(
        name='SectionHeader',
        parent=styles['Heading2'],
        fontSize=12,
        leading=14,
        spaceBefore=15,
        spaceAfter=10,
        textColor=colors.darkblue,
        underlineWidth=1,
        underlineColor=colors.darkblue,
        underlineOffset=-5
    ))

    styles.add(ParagraphStyle(
        name='LeftColumn',
        parent=styles['BodyText'],
        fontSize=10,
        leading=12,
        alignment=TA_JUSTIFY,
        leftIndent=0,
        rightIndent=5,
        spaceAfter=7
    ))

    styles.add(ParagraphStyle(
        name='RightColumn',
        parent=styles['BodyText'],
        fontSize=10,
        leading=12,
        alignment=TA_JUSTIFY,
        leftIndent=5,
        rightIndent=0,
        spaceAfter=7
    ))

    styles.add(ParagraphStyle(
        name='BulletPoint',
        parent=styles['BodyText'],
        fontSize=10,
        leading=12,
        leftIndent=15,
        bulletIndent=0,
        spaceAfter=3,
        bulletFontName='Symbol',
        bulletFontSize=8
    ))

    styles.add(ParagraphStyle(
        name='Reference',
        parent=styles['Italic'],
        fontSize=8,
        leading=10,
        textColor=colors.darkgrey,
        spaceBefore=15
    ))

    # Create document with two columns
    class TwoColumnDocTemplate(BaseDocTemplate):
        def __init__(self, filename, **kw):
            BaseDocTemplate.__init__(self, filename, **kw)
            # Calculate column widths
            page_width = self.pagesize[0] - 2*self.leftMargin
            col_width = (page_width - 1*cm) / 2  # 1cm gutter

            # First page template with title
            first_page = PageTemplate(id='FirstPage',
                frames=[
                    Frame(self.leftMargin, self.bottomMargin, 
                          col_width, self.height, 
                          id='leftCol'),
                    Frame(self.leftMargin + col_width + 1*cm, 
                          self.bottomMargin, 
                          col_width, self.height, 
                          id='rightCol')
                ])
            self.addPageTemplates(first_page)

            # Other pages template
            other_pages = PageTemplate(id='OtherPages',
                frames=[
                    Frame(self.leftMargin, self.bottomMargin, 
                          col_width, self.height, 
                          id='leftCol2'),
                    Frame(self.leftMargin + col_width + 1*cm, 
                          self.bottomMargin, 
                          col_width, self.height, 
                          id='rightCol2')
                ])
            self.addPageTemplates(other_pages)

    doc = TwoColumnDocTemplate(filename,
                             pagesize=letter,
                             leftMargin=2*cm,
                             rightMargin=2*cm,
                             topMargin=2*cm,
                             bottomMargin=2*cm)

    story = []

    # Add logo at the top (centered)
    try:
        logo = Image('app/data/logo_platform.jpg', width=6*cm, height=2*cm)
        logo.hAlign = 'CENTER'
        story.append(logo)
        story.append(Spacer(1, 0.3*cm))
    except Exception as e:
        pass  # If logo not found, skip

    # Title and authors
    title = Paragraph(disease_info.get('Title', 'Medical Condition Report'), styles['TitleStyle'])
    authors = Paragraph("Generated by AIHealthCheck AI Assistant", styles['AuthorStyle'])
    date = Paragraph(datetime.now().strftime("%B %d, %Y"), styles['AuthorStyle'])

    story.append(title)
    story.append(authors)
    story.append(date)
    story.append(NextPageTemplate('OtherPages'))  # Switch to two-column layout

    # Abstract
    abstract_text = f"<b>Abstract</b><br/><br/>{disease_info.get('Overview', 'No overview available.')}"
    abstract = Paragraph(abstract_text, styles['AbstractStyle'])
    story.append(abstract)

    # Function to format content

    def format_content(text, styles):
        if not text:
            return []

        # If it's a list, return each item as a bullet paragraph
        if isinstance(text, list):
            return [Paragraph(f"• {item}", styles) for item in text]

        # If it's a dict, render each key-value pair
        if isinstance(text, dict):
            items = []
            for key, value in text.items():
                if isinstance(value, list):
                    items.append(Paragraph(f"<b>{key}:</b>", styles))
                    items.extend([Paragraph(f"• {v}", styles) for v in value])
                else:
                    items.append(Paragraph(f"• <b>{key}:</b> {value}", styles))
            return items

        # Otherwise, treat it as a simple paragraph
        return [Paragraph(text, styles)]



    # Organize content into left and right columns
    left_column_content = [
        ('Symptoms', disease_info.get('Symptoms')),
        ('Causes', disease_info.get('Causes')),
        ('Risk Factors', disease_info.get('Risk factors')),
        ('Complications', disease_info.get('Complications'))
    ]

    right_column_content = [
        ('Diagnosis', disease_info.get('Diagnosis')),
        ('Treatment', disease_info.get('Treatment')),
        ('Prevention', disease_info.get('Prevention')),
        ('When to See a Doctor', disease_info.get('When to see a doctor')),
        ('Lifestyle and Home Remedies', disease_info.get('Lifestyle and home remedies'))
    ]

    # Add left column content
    for section, content in left_column_content:
        if content:
            story.append(Paragraph(section, styles['SectionHeader']))
            formatted = format_content(content, styles['LeftColumn'])
            if isinstance(formatted, list):
                story.extend(formatted)
            else:
                story.append(formatted)

    # Switch to right column
    story.append(NextPageTemplate('OtherPages'))

    # Add right column content
    for section, content in right_column_content:
        if content:
            story.append(Paragraph(section, styles['SectionHeader']))
            formatted = format_content(content, styles['RightColumn'])
            if isinstance(formatted, list):
                story.extend(formatted)
            else:
                story.append(formatted)

    # Add references
    story.append(Paragraph("Medical Recommendations", styles['SectionHeader']))
    story.append(Paragraph(disease_info.get('Medical Recommendation', 'No medical recommendations available.'), styles['LeftColumn']))
    story.append(Paragraph("References", styles['SectionHeader']))
    story.append(Paragraph("1. Mayo Clinic Medical References", styles['Reference']))

    # Build the PDF
    doc.build(story)