# utils/pdf_generator.py pdf generator module
from fpdf import FPDF
from datetime import datetime
import os
import json
import re


class PDFGenerator:
    def __init__(self):
        # No initialization needed for this class
        pass
    def clean_text(self, text: str) -> str:
        replacements = {
            "→": "->",
            "–": "-",
            "—": "-",
            "…": "...",
        }
        for old, new in replacements.items():
            text = text.replace(old, new)
        return re.sub(r'[^\x00-\x7F]+', '', str(text))
    # At the top of utils/pdf_generator.py
    def safe_load(self, data):
        """Convert JSON string to dict if needed."""
        if isinstance(data, str):
            try:
                return json.loads(data)
            except json.JSONDecodeError:
                return {}
        return data

    def generate_pdf(self,idea: str, structured: dict, scores: dict, suggestions: dict, feedback: dict,chats: list, user_id: str) -> str:
        # Convert inputs
        structured = self.safe_load(structured)
        scores = self.safe_load(scores)
        suggestions = self.safe_load(suggestions)
        feedback = self.safe_load(feedback)

        pdf = FPDF()
        pdf.set_auto_page_break(auto=True, margin=15)
        pdf.add_page()
        pdf.set_font("Arial", 'B', 20)
        pdf.cell(0, 100, "Startup Idea Evaluation Report", ln=True, align='C')
        pdf.set_font("Arial", '', 14)
        pdf.cell(0, 10, f"Idea Name: {idea}", ln=True, align='C')
        pdf.ln(10)
        pdf.set_font("Arial", 'I', 12)
        pdf.cell(0, 10, f"Generated on {datetime.now().strftime('%Y-%m-%d')}", ln=True, align='C')
        pdf.add_page()  # then continue with details


        # Structured Format
        pdf.set_font("Arial", 'B', 12)
        pdf.cell(0, 10, "Structured Format:", ln=True)
        pdf.set_font("Arial", '', 11)
        for key, value in structured.items():
            pdf.multi_cell(0, 8, f"- {key.capitalize()}: {self.clean_text(value)}")
        pdf.ln(5)

        # Scores
        pdf.set_font("Arial", 'B', 12)
        pdf.cell(0, 10, "Scores:", ln=True)
        pdf.set_font("Arial", '', 11)
        for key, value in scores.items():
            pdf.multi_cell(0, 8, f"- {key}: {value}")
        pdf.ln(5)

        # Suggestions
        pdf.set_font("Arial", 'B', 12)
        pdf.cell(0, 10, "Suggestions:", ln=True)
        pdf.set_font("Arial", '', 11)
        for i, suggestion in enumerate(suggestions.get("improvements", []), start=1):
            pdf.multi_cell(0, 8, f"{i}. {self.clean_text(suggestion)}")
        pdf.ln(2)
        pdf.set_font("Arial", 'I', 10)
        for i, rationale in enumerate(suggestions.get("rationale", []), start=1):
            pdf.multi_cell(0, 7, f"   Rationale {i}: {self.clean_text(rationale)}")
        pdf.ln(5)

        # Feedback
        pdf.set_font("Arial", 'B', 12)
        pdf.cell(0, 10, "Feedback:", ln=True)
        pdf.set_font("Arial", '', 11)
        for i, fb in enumerate(feedback.get("feedbacks", []), start=1):
            pdf.multi_cell(0, 8, f"{i}. {self.clean_text(fb)}")
            pdf.ln(2)
        
        pdf.add_page()
        pdf.set_font("Arial", 'B', 16)
        pdf.cell(0, 10, "Expert Chats", ln=True, align='C')
        pdf.ln(5)

        if chats and len(chats) > 0:
            for expert in chats:
                pdf.set_font("Arial", 'B', 13)
                pdf.cell(0, 8, f"Expert: {expert.get('name', '')} ({expert.get('expertise', '')})", ln=True)
                pdf.set_font("Arial", 'I', 11)
                pdf.multi_cell(0, 6, f"Bio: {self.clean_text(expert.get('bio', ''))}")
                pdf.multi_cell(0, 6, f"Email: {expert.get('email', '')}")
                pdf.ln(3)

                chat = expert.get("chat", {})
                chathistory = chat.get("chathistory", [])

                if chathistory:
                    pdf.set_font("Arial", '', 11)
                    for msg in chathistory:
                        timestamp = datetime.fromisoformat(msg["timestamp"].replace("Z", "+00:00")).strftime("%Y-%m-%d %H:%M")
                        sender = msg.get("sender", "unknown").capitalize()
                        message = self.clean_text(msg.get("message", ""))
                        pdf.multi_cell(0, 8, f"[{timestamp}] {sender}: {message}")
                    pdf.ln(6)
                else:
                    pdf.set_font("Arial", 'I', 11)
                    pdf.cell(0, 8, "No messages found.", ln=True)
                    pdf.ln(5)
        else:
            pdf.set_font("Arial", 'I', 12)
            pdf.cell(0, 10, "No expert chats available.", ln=True, align='C')

        # Footer
        pdf.set_y(-30)
        pdf.set_font("Arial", 'I', 8)
        pdf.cell(0, 10, f"Generated by SIV | Version: {4.0} | Date: {datetime.now().strftime('%Y-%m-%d %H:%M:%S')}", align='C')

        # Save file
        output_dir = "/mnt/data"
        os.makedirs(output_dir, exist_ok=True)
        output_path = os.path.join(output_dir, f"{user_id}_startup_report.pdf")
        pdf.output(output_path)

        return output_path