"""
PDF export utility for dashboard data
Generates PDF reports matching the Analytics Dashboard exactly
"""
import io
import os
from datetime import datetime
from reportlab.lib import colors
from reportlab.lib.pagesizes import letter
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.units import inch
from reportlab.platypus import SimpleDocTemplate, Table, TableStyle, Paragraph, Spacer, PageBreak, Image
from reportlab.lib.enums import TA_CENTER

# Set matplotlib config directory before import (prevent permission errors on HuggingFace)
os.environ.setdefault('MPLCONFIGDIR', '/tmp/matplotlib')
import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
try:
    import contextily as cx
    HAS_CONTEXTILY = True
except ImportError:
    HAS_CONTEXTILY = False


class DashboardPDFExporter:
    """Export dashboard data to PDF matching the Analytics Dashboard"""

    CATEGORY_COLORS = {
        'Vision': '#3b82f6', 'Problem': '#ef4444', 'Objectives': '#10b981',
        'Directives': '#f59e0b', 'Values': '#8b5cf6', 'Actions': '#ec4899'
    }

    def __init__(self, pagesize=letter):
        self.pagesize = pagesize
        self.styles = getSampleStyleSheet()
        self._setup_custom_styles()

    def _setup_custom_styles(self):
        self.styles.add(ParagraphStyle(
            name='CustomTitle', parent=self.styles['Heading1'], fontSize=20,
            textColor=colors.HexColor('#2c3e50'), spaceAfter=20, alignment=TA_CENTER
        ))
        self.styles.add(ParagraphStyle(
            name='SectionHeader', parent=self.styles['Heading2'], fontSize=14,
            textColor=colors.HexColor('#34495e'), spaceAfter=10, spaceBefore=15
        ))
        self.styles.add(ParagraphStyle(
            name='CategoryHeader', fontSize=12, textColor=colors.HexColor('#2c3e50'),
            spaceAfter=8, spaceBefore=10, fontName='Helvetica-Bold'
        ))
        self.styles.add(ParagraphStyle(
            name='SubmissionText', fontSize=10, textColor=colors.HexColor('#2c3e50'),
            spaceAfter=4, leftIndent=15
        ))
        self.styles.add(ParagraphStyle(
            name='SubmissionMeta', fontSize=8, textColor=colors.HexColor('#7f8c8d'),
            spaceAfter=2, leftIndent=15
        ))

    def generate_pdf(self, buffer, data):
        doc = SimpleDocTemplate(buffer, pagesize=self.pagesize,
                               rightMargin=50, leftMargin=50, topMargin=50, bottomMargin=30)
        story = []

        # Title
        story.append(Paragraph("Participatory Planning - Analytics Dashboard", self.styles['CustomTitle']))
        view_mode_label = "Sentence-Level Analysis" if data['view_mode'] == 'sentences' else "Submission-Level Analysis"
        story.append(Paragraph(
            f"<font size=9>Generated: {datetime.now().strftime('%B %d, %Y at %H:%M')}<br/>"
            f"Analysis Mode: <b>{view_mode_label}</b></font>", self.styles['Normal']
        ))
        story.append(Spacer(1, 20))

        # Charts
        story.append(Paragraph("Distribution Overview", self.styles['SectionHeader']))
        charts = self._create_charts_side_by_side(data)
        if charts:
            story.append(charts)
        story.append(Spacer(1, 15))

        # Map
        if data['geotagged_submissions']:
            story.append(Paragraph(f"Geographic Distribution ({len(data['geotagged_submissions'])} geotagged)", self.styles['SectionHeader']))
            map_image = self._create_map(data['geotagged_submissions'])
            if map_image:
                story.append(map_image)
            story.append(Spacer(1, 15))

        # Contributions list
        story.append(PageBreak())
        story.append(Paragraph("Contributions by Category", self.styles['SectionHeader']))
        story.extend(self._create_contributions_list(data))

        # Breakdown table
        story.append(PageBreak())
        story.append(Paragraph("Category Breakdown by Contributor Type", self.styles['SectionHeader']))
        story.append(self._create_breakdown_table(data['breakdown'], data['contributor_types']))

        doc.build(story)
        return buffer

    def _create_charts_side_by_side(self, data):
        try:
            fig, (ax1, ax2) = plt.subplots(1, 2, figsize=(10, 4))
            
            # Contributor pie
            contributor_labels = [ctype for ctype, _ in data['contributor_stats']]
            contributor_values = [count for _, count in data['contributor_stats']]
            colors1 = ['#3b82f6', '#10b981', '#f59e0b', '#ef4444', '#8b5cf6', '#ec4899']
            ax1.pie(contributor_values, labels=contributor_labels, autopct='%1.1f%%',
                   colors=colors1[:len(contributor_labels)], startangle=90)
            ax1.set_title('By Contributor Type', fontsize=11, fontweight='bold')

            # Category bar
            category_labels = [cat for cat, _ in data['category_stats']]
            category_values = [count for _, count in data['category_stats']]
            category_colors = [self.CATEGORY_COLORS.get(cat, '#95a5a6') for cat in category_labels]
            bars = ax2.bar(range(len(category_labels)), category_values, color=category_colors, edgecolor='#2c3e50')
            ax2.set_xticks(range(len(category_labels)))
            ax2.set_xticklabels(category_labels, rotation=45, ha='right', fontsize=9)
            ax2.set_ylabel('Count', fontsize=10)
            ax2.set_title('By Category', fontsize=11, fontweight='bold')
            ax2.grid(axis='y', alpha=0.3)
            for bar in bars:
                height = bar.get_height()
                ax2.text(bar.get_x() + bar.get_width()/2., height, f'{int(height)}', ha='center', va='bottom', fontsize=9)

            plt.tight_layout()
            img_buffer = io.BytesIO()
            plt.savefig(img_buffer, format='png', dpi=150, bbox_inches='tight')
            plt.close(fig)
            img_buffer.seek(0)
            return Image(img_buffer, width=7*inch, height=2.8*inch)
        except Exception as e:
            print(f"Error creating charts: {e}")
            return None

    def _create_contributions_list(self, data):
        elements = []
        submissions_by_category = {}
        for sub in data['submissions']:
            cat = sub.category
            if cat not in submissions_by_category:
                submissions_by_category[cat] = []
            submissions_by_category[cat].append(sub)

        for category in data['categories']:
            if category not in submissions_by_category:
                continue
            category_subs = submissions_by_category[category]
            if not category_subs:
                continue

            color = self.CATEGORY_COLORS.get(category, '#95a5a6')
            count_text = f"({len(category_subs)} contribution{'s' if len(category_subs) != 1 else ''})"
            header_text = f'<font color="{color}"><b>{category}</b></font> <font size=9 color="#7f8c8d">{count_text}</font>'
            elements.append(Paragraph(header_text, self.styles['CategoryHeader']))
            elements.append(Spacer(1, 5))

            for sub in category_subs:
                meta_text = f'<font color="#7f8c8d"><i>{sub.contributor_type.title()}</i></font>'
                if sub.timestamp:
                    meta_text += f' <font color="#95a5a6">• {sub.timestamp.strftime("%Y-%m-%d")}</font>'
                elements.append(Paragraph(meta_text, self.styles['SubmissionMeta']))
                
                text = sub.message.replace('<', '&lt;').replace('>', '&gt;').replace('&', '&amp;')
                elements.append(Paragraph(text, self.styles['SubmissionText']))
                
                if sub.latitude and sub.longitude:
                    loc_text = f'<font color="#95a5a6" size=8>📍 {sub.latitude:.4f}, {sub.longitude:.4f}</font>'
                    elements.append(Paragraph(loc_text, self.styles['SubmissionMeta']))
                elements.append(Spacer(1, 8))
            elements.append(Spacer(1, 10))
        return elements

    def _create_breakdown_table(self, breakdown, contributor_types):
        headers = ['Category'] + [ct['label'] for ct in contributor_types]
        data = [headers]
        for category, counts in breakdown.items():
            row = [category]
            for ct in contributor_types:
                count = counts.get(ct['value'], 0)
                row.append(str(count) if count > 0 else '-')
            data.append(row)

        num_cols = len(headers)
        col_width = 7 * inch / num_cols
        table = Table(data, colWidths=[col_width] * num_cols)
        table.setStyle(TableStyle([
            ('BACKGROUND', (0, 0), (-1, 0), colors.HexColor('#3498db')),
            ('TEXTCOLOR', (0, 0), (-1, 0), colors.whitesmoke),
            ('ALIGN', (0, 0), (-1, -1), 'CENTER'),
            ('FONTNAME', (0, 0), (-1, 0), 'Helvetica-Bold'),
            ('FONTSIZE', (0, 0), (-1, -1), 9),
            ('BOTTOMPADDING', (0, 0), (-1, 0), 10),
            ('TOPPADDING', (0, 0), (-1, 0), 10),
            ('GRID', (0, 0), (-1, -1), 0.5, colors.grey),
            ('ROWBACKGROUNDS', (0, 1), (-1, -1), [colors.white, colors.HexColor('#f8f9fa')])
        ]))
        return table

    def _create_map(self, geotagged_submissions):
        if not geotagged_submissions:
            return None
        try:
            lats = [s.latitude for s in geotagged_submissions]
            lons = [s.longitude for s in geotagged_submissions]
            cats = [s.category for s in geotagged_submissions]

            fig, ax = plt.subplots(figsize=(10, 6))
            for category in set(cats):
                cat_lats = [lat for lat, cat in zip(lats, cats) if cat == category]
                cat_lons = [lon for lon, cat in zip(lons, cats) if cat == category]
                color = self.CATEGORY_COLORS.get(category, '#95a5a6')
                ax.scatter(cat_lons, cat_lats, c=color, label=category,
                          s=150, alpha=0.8, edgecolors='white', linewidths=2.5, zorder=5)

            if HAS_CONTEXTILY:
                try:
                    cx.add_basemap(ax, crs='EPSG:4326', source=cx.providers.OpenStreetMap.Mapnik,
                                  attribution=False, alpha=0.8, zoom='auto')
                except Exception as e:
                    print(f"Could not add basemap: {e}")
                    ax.grid(True, alpha=0.3, linestyle='--')
            else:
                ax.grid(True, alpha=0.3, linestyle='--')

            ax.set_xlabel('Longitude', fontsize=11, fontweight='bold')
            ax.set_ylabel('Latitude', fontsize=11, fontweight='bold')
            ax.legend(loc='upper left', bbox_to_anchor=(1.02, 1), fontsize=9,
                     frameon=True, fancybox=True, shadow=True)

            if HAS_CONTEXTILY:
                fig.text(0.99, 0.01, '© OpenStreetMap contributors',
                        ha='right', va='bottom', fontsize=7, style='italic', alpha=0.7)

            img_buffer = io.BytesIO()
            plt.tight_layout()
            plt.savefig(img_buffer, format='png', dpi=200, bbox_inches='tight')
            plt.close(fig)
            img_buffer.seek(0)
            return Image(img_buffer, width=7*inch, height=4.5*inch)
        except Exception as e:
            print(f"Error creating map: {e}")
            import traceback
            traceback.print_exc()
            return None