"""
FORENSIQ — Export Module
Generates professional forensic reports in PDF, DOCX, TXT, MD formats.
Uses Qwen2.5-72B-Instruct (text model) for polished formatting when available.
"""

import os
import io
import re
import json
import tempfile
import datetime
from typing import Optional


# ─── LLM Formatter ──────────────────────────────────────────────────

def _format_with_llm(raw_report: str, format_type: str) -> Optional[str]:
    """Skip LLM formatting — export instantly with raw data.
    The reports from explanation.py are already professionally formatted."""
    return None


# ─── Strip Markdown Helper ──────────────────────────────────────────

def _strip_md(text: str) -> str:
    """Convert markdown to plain text."""
    text = re.sub(r'#{1,6}\s*', '', text)  # Headers
    text = re.sub(r'\*\*([^*]+)\*\*', r'\1', text)  # Bold
    text = re.sub(r'\*([^*]+)\*', r'\1', text)  # Italic
    text = re.sub(r'`([^`]+)`', r'\1', text)  # Inline code
    text = re.sub(r'```[^`]*```', '', text, flags=re.DOTALL)  # Code blocks
    text = re.sub(r'\|[^\n]+\|', lambda m: m.group().replace('|', '  '), text)  # Tables
    text = re.sub(r'---+', '=' * 60, text)  # Horizontal rules
    text = re.sub(r'[🔬🔴🟢🟡🟠⚪✅⚖️📊📋🌳🔍📐]', '', text)  # Emojis
    text = re.sub(r'\n{3,}', '\n\n', text)  # Multiple newlines
    return text.strip()


# ─── PDF Export ──────────────────────────────────────────────────────

def export_pdf(report_md: str, court_brief_md: str, reasoning_tree_md: str) -> str:
    """Generate a professional PDF forensic report."""
    from fpdf import FPDF
    
    # Try LLM formatting first
    formatted = _format_with_llm(report_md, "PDF document")
    content = _strip_md(formatted if formatted else report_md)
    court_content = _strip_md(court_brief_md) if court_brief_md else ""
    tree_content = _strip_md(reasoning_tree_md) if reasoning_tree_md else ""
    
    pdf = FPDF()
    pdf.set_auto_page_break(auto=True, margin=15)
    pdf.set_left_margin(15)
    pdf.set_right_margin(15)
    
    # ── Cover Page ────────────────────────────────────────────────
    pdf.add_page()
    pdf.set_font("Helvetica", "B", 28)
    pdf.cell(0, 60, "", ln=True)
    pdf.cell(0, 15, "FORENSIQ", ln=True, align="C")
    pdf.set_font("Helvetica", "", 14)
    pdf.cell(0, 10, "Forensic Analysis Report", ln=True, align="C")
    pdf.set_font("Helvetica", "", 10)
    pdf.cell(0, 8, "", ln=True)
    pdf.cell(0, 8, f"Generated: {datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S UTC')}", ln=True, align="C")
    pdf.cell(0, 8, "Physics-Based Multi-Agent Forensic Framework", ln=True, align="C")
    pdf.cell(0, 8, "for Explainable Deepfake Detection", ln=True, align="C")
    
    # ── Main Report ───────────────────────────────────────────────
    pdf.add_page()
    pdf.set_font("Helvetica", "B", 16)
    pdf.cell(0, 12, "FORENSIC ANALYSIS REPORT", ln=True)
    pdf.line(10, pdf.get_y(), 200, pdf.get_y())
    pdf.cell(0, 5, "", ln=True)
    
    pdf.set_font("Helvetica", "", 9)
    for line in content.split('\n'):
        line = line.strip()
        if not line:
            pdf.cell(0, 4, "", ln=True)
            continue
        # Detect section headers
        if line.startswith('Overall Verdict') or line.startswith('Key Evidence') or \
           line.startswith('Agent-by-Agent') or line.startswith('Bayesian') or \
           line.startswith('Methodology') or line.startswith('I.') or line.startswith('II.') or \
           line.startswith('III.') or line.startswith('IV.') or line.startswith('V.') or \
           line.startswith('VI.'):
            pdf.set_font("Helvetica", "B", 11)
            pdf.cell(0, 8, "", ln=True)
            safe = line[:85].encode('latin-1', 'replace').decode('latin-1')
            pdf.cell(0, 8, safe, ln=True)
            pdf.set_font("Helvetica", "", 9)
        else:
            safe_line = line.encode('latin-1', 'replace').decode('latin-1')
            # Truncate very long lines to fit page width
            try:
                pdf.multi_cell(0, 5, safe_line[:180])
            except Exception:
                pdf.cell(0, 5, safe_line[:80], ln=True)
    
    # ── Court Brief ───────────────────────────────────────────────
    if court_content:
        pdf.add_page()
        pdf.set_font("Helvetica", "B", 16)
        pdf.cell(0, 12, "EXPERT FORENSIC ANALYSIS BRIEF", ln=True)
        pdf.line(10, pdf.get_y(), 200, pdf.get_y())
        pdf.cell(0, 5, "", ln=True)
        pdf.set_font("Helvetica", "", 9)
        for line in court_content.split('\n'):
            line = line.strip()
            if not line:
                pdf.cell(0, 4, "", ln=True)
            else:
                safe_line = line.encode('latin-1', 'replace').decode('latin-1')
                try:
                    pdf.multi_cell(0, 5, safe_line[:180])
                except Exception:
                    pdf.cell(0, 5, safe_line[:80], ln=True)
    
    # ── Reasoning Tree ────────────────────────────────────────────
    if tree_content:
        pdf.add_page()
        pdf.set_font("Helvetica", "B", 16)
        pdf.cell(0, 12, "REASONING TREE", ln=True)
        pdf.line(10, pdf.get_y(), 200, pdf.get_y())
        pdf.cell(0, 5, "", ln=True)
        pdf.set_font("Courier", "", 8)
        for line in tree_content.split('\n'):
            safe_line = line.encode('latin-1', 'replace').decode('latin-1')
            try:
                pdf.multi_cell(0, 4, safe_line[:120])
            except Exception:
                pdf.cell(0, 4, safe_line[:60], ln=True)
    
    # Save
    path = tempfile.mktemp(suffix=".pdf", prefix="FORENSIQ_Report_")
    pdf.output(path)
    return path


# ─── DOCX Export ─────────────────────────────────────────────────────

def export_docx(report_md: str, court_brief_md: str, reasoning_tree_md: str) -> str:
    """Generate a professional DOCX forensic report."""
    from docx import Document
    from docx.shared import Inches, Pt, RGBColor
    from docx.enum.text import WD_ALIGN_PARAGRAPH
    
    # Try LLM formatting
    formatted = _format_with_llm(report_md, "Word document")
    content = formatted if formatted else report_md
    
    doc = Document()
    
    # ── Title ─────────────────────────────────────────────────────
    title = doc.add_heading('FORENSIQ', level=0)
    title.alignment = WD_ALIGN_PARAGRAPH.CENTER
    
    subtitle = doc.add_paragraph()
    subtitle.alignment = WD_ALIGN_PARAGRAPH.CENTER
    run = subtitle.add_run('Forensic Analysis Report')
    run.font.size = Pt(14)
    run.font.color.rgb = RGBColor(100, 100, 100)
    
    date_para = doc.add_paragraph()
    date_para.alignment = WD_ALIGN_PARAGRAPH.CENTER
    run = date_para.add_run(f'Generated: {datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S UTC")}')
    run.font.size = Pt(10)
    run.font.color.rgb = RGBColor(150, 150, 150)
    
    doc.add_page_break()
    
    # ── Parse and add content ─────────────────────────────────────
    def add_md_content(md_text, doc):
        for line in md_text.split('\n'):
            stripped = line.strip()
            if not stripped:
                continue
            
            # Headings
            if stripped.startswith('# '):
                doc.add_heading(re.sub(r'[🔬🔴🟢🟡🟠⚪✅⚖️📊📋🌳🔍📐]', '', stripped[2:]).strip(), level=1)
            elif stripped.startswith('## '):
                doc.add_heading(re.sub(r'[🔬🔴🟢🟡🟠⚪✅⚖️📊📋🌳🔍📐]', '', stripped[3:]).strip(), level=2)
            elif stripped.startswith('### '):
                doc.add_heading(re.sub(r'[🔬🔴🟢🟡🟠⚪✅⚖️📊📋🌳🔍📐]', '', stripped[4:]).strip(), level=3)
            elif stripped.startswith('---'):
                doc.add_paragraph('_' * 50)
            elif stripped.startswith('- ') or stripped.startswith('* '):
                doc.add_paragraph(stripped[2:], style='List Bullet')
            elif stripped.startswith('|') and '|' in stripped[1:]:
                # Table row — just add as plain text
                cells = [c.strip() for c in stripped.split('|') if c.strip() and c.strip() != '---']
                if cells:
                    doc.add_paragraph('  |  '.join(cells))
            else:
                # Regular paragraph
                p = doc.add_paragraph()
                # Handle bold
                parts = re.split(r'\*\*([^*]+)\*\*', stripped)
                for i, part in enumerate(parts):
                    if not part:
                        continue
                    run = p.add_run(part)
                    if i % 2 == 1:
                        run.bold = True
                    run.font.size = Pt(10)
    
    doc.add_heading('Forensic Analysis Report', level=1)
    add_md_content(content, doc)
    
    if court_brief_md:
        doc.add_page_break()
        doc.add_heading('Expert Forensic Analysis Brief', level=1)
        add_md_content(court_brief_md, doc)
    
    if reasoning_tree_md:
        doc.add_page_break()
        doc.add_heading('Reasoning Tree', level=1)
        add_md_content(reasoning_tree_md, doc)
    
    path = tempfile.mktemp(suffix=".docx", prefix="FORENSIQ_Report_")
    doc.save(path)
    return path


# ─── TXT Export ──────────────────────────────────────────────────────

def export_txt(report_md: str, court_brief_md: str, reasoning_tree_md: str) -> str:
    """Generate a plain text forensic report."""
    # Try LLM formatting
    formatted = _format_with_llm(report_md, "plain text document")
    content = _strip_md(formatted if formatted else report_md)
    
    full = "=" * 60 + "\n"
    full += "  FORENSIQ — FORENSIC ANALYSIS REPORT\n"
    full += f"  Generated: {datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S UTC')}\n"
    full += "=" * 60 + "\n\n"
    full += content
    
    if court_brief_md:
        full += "\n\n" + "=" * 60 + "\n"
        full += "  EXPERT FORENSIC ANALYSIS BRIEF (FRE 702)\n"
        full += "=" * 60 + "\n\n"
        full += _strip_md(court_brief_md)
    
    if reasoning_tree_md:
        full += "\n\n" + "=" * 60 + "\n"
        full += "  REASONING TREE\n"
        full += "=" * 60 + "\n\n"
        full += _strip_md(reasoning_tree_md)
    
    path = tempfile.mktemp(suffix=".txt", prefix="FORENSIQ_Report_")
    with open(path, 'w', encoding='utf-8') as f:
        f.write(full)
    return path


# ─── MD Export ───────────────────────────────────────────────────────

def export_md(report_md: str, court_brief_md: str, reasoning_tree_md: str) -> str:
    """Export as Markdown file."""
    full = report_md or ""
    if court_brief_md:
        full += "\n\n---\n\n" + court_brief_md
    if reasoning_tree_md:
        full += "\n\n---\n\n" + reasoning_tree_md
    
    path = tempfile.mktemp(suffix=".md", prefix="FORENSIQ_Report_")
    with open(path, 'w', encoding='utf-8') as f:
        f.write(full)
    return path