#!/usr/bin/env python3
"""
RCA (Root Cause Analysis) template generator for Ezra.
Creates structured RCA documents from incident parameters.

Epic: EZRA-SELF-001 / Phase 4 - Self-Monitoring & RCA
Author: Ezra (self-improvement)
"""

import json
from datetime import datetime
from pathlib import Path
from typing import Optional


class RCAGenerator:
    """Generate structured RCA documents."""

    SEVERITY_LEVELS = {
        "P0": "Critical - Service down, data loss risk",
        "P1": "High - Major feature broken, workaround exists",
        "P2": "Medium - Feature degraded, minor impact",
        "P3": "Low - Cosmetic, minor inconvenience",
    }

    TEMPLATE = """# RCA-{number}: {title}

## Summary
| Field | Value |
|-------|-------|
| **Date** | {date} |
| **Severity** | {severity} - {severity_desc} |
| **Duration** | {duration} |
| **Affected** | {affected} |
| **Status** | {status} |

## Timeline
{timeline}

## Root Cause
{root_cause}

## Impact
{impact}

## Resolution
{resolution}

## 5-Whys Analysis
{five_whys}

## Action Items
{action_items}

## Lessons Learned
{lessons}

## Prevention
{prevention}

---
Generated by: Ezra RCA Generator
Date: {generated}
"""

    def __init__(self, rca_dir: str = None):
        self.rca_dir = Path(rca_dir or "/root/wizards/ezra/reports/rca")
        self.rca_dir.mkdir(parents=True, exist_ok=True)

    def _next_number(self) -> int:
        """Get next RCA number."""
        existing = list(self.rca_dir.glob("RCA-*.md"))
        if not existing:
            return 1
        numbers = []
        for f in existing:
            try:
                num = int(f.stem.split("-")[1])
                numbers.append(num)
            except (IndexError, ValueError):
                pass
        return max(numbers, default=0) + 1

    def generate(
        self,
        title: str,
        severity: str = "P2",
        duration: str = "Unknown",
        affected: str = "Ezra wizard house",
        root_cause: str = "Under investigation",
        impact: str = "TBD",
        resolution: str = "TBD",
        timeline: list[dict] = None,
        five_whys: list[str] = None,
        action_items: list[dict] = None,
        lessons: list[str] = None,
        prevention: list[str] = None,
        status: str = "Open",
        number: int = None,
    ) -> tuple[str, Path]:
        """Generate an RCA document. Returns (content, file_path)."""

        if number is None:
            number = self._next_number()

        # Format timeline
        if timeline:
            timeline_str = "\n".join(
                f"- **{t.get('time', '??:??')}** - {t.get('event', 'Unknown event')}"
                for t in timeline
            )
        else:
            timeline_str = "- TBD - Add timeline entries"

        # Format 5-whys
        if five_whys:
            five_whys_str = "\n".join(
                f"{i+1}. **Why?** {why}" for i, why in enumerate(five_whys)
            )
        else:
            five_whys_str = "1. **Why?** TBD\n2. **Why?** TBD\n3. **Why?** TBD"

        # Format action items
        if action_items:
            action_items_str = "\n".join(
                f"- [ ] **[{a.get('priority', 'P2')}]** {a.get('action', 'TBD')} "
                f"(Owner: {a.get('owner', 'Ezra')})"
                for a in action_items
            )
        else:
            action_items_str = "- [ ] **[P2]** Add action items (Owner: Ezra)"

        # Format lessons
        lessons_str = "\n".join(f"- {l}" for l in (lessons or ["TBD"]))
        prevention_str = "\n".join(f"- {p}" for p in (prevention or ["TBD"]))

        content = self.TEMPLATE.format(
            number=number,
            title=title,
            date=datetime.now().strftime("%Y-%m-%d"),
            severity=severity,
            severity_desc=self.SEVERITY_LEVELS.get(severity, "Unknown"),
            duration=duration,
            affected=affected,
            status=status,
            root_cause=root_cause,
            impact=impact,
            resolution=resolution,
            timeline=timeline_str,
            five_whys=five_whys_str,
            action_items=action_items_str,
            lessons=lessons_str,
            prevention=prevention_str,
            generated=datetime.now().isoformat(),
        )

        import re as _re
        safe_title = _re.sub(r'[^a-z0-9-]', '', title.lower().replace(' ', '-'))[:40]
        file_path = self.rca_dir / f"RCA-{number}-{safe_title}.md"
        file_path.write_text(content)

        return content, file_path

    def list_rcas(self) -> list[dict]:
        """List existing RCAs."""
        rcas = []
        for f in sorted(self.rca_dir.glob("RCA-*.md")):
            first_line = f.read_text().splitlines()[0] if f.stat().st_size > 0 else ""
            rcas.append({
                "file": f.name,
                "title": first_line.replace("# ", ""),
                "size": f.stat().st_size,
                "modified": datetime.fromtimestamp(f.stat().st_mtime).isoformat(),
            })
        return rcas


if __name__ == "__main__":
    gen = RCAGenerator()
    content, path = gen.generate(
        title="Example RCA",
        severity="P2",
        duration="30 minutes",
        root_cause="Example root cause for testing",
        timeline=[
            {"time": "10:00", "event": "Issue detected"},
            {"time": "10:15", "event": "Investigation started"},
            {"time": "10:30", "event": "Root cause identified and fixed"},
        ],
        five_whys=[
            "The API returned 401",
            "Token was expired",
            "No token refresh automation existed",
        ],
        action_items=[
            {"priority": "P1", "action": "Implement token auto-refresh", "owner": "Ezra"},
        ],
        status="Resolved",
    )
    print(f"Generated: {path}")
    print(content)