"""
Node router — handles /health, /api/v1/verify/{cid}, and /api/v1/node/info endpoints.
"""

import hashlib
import json
from datetime import datetime

import httpx
from fastapi import APIRouter

from dependencies import ipfs_cat
from config import IPFS_API_URL

router = APIRouter()


@router.get("/health")
async def health_check():
    """Health Check für DSMS Gateway"""
    try:
        async with httpx.AsyncClient(timeout=5.0) as client:
            response = await client.post(f"{IPFS_API_URL}/api/v0/id")
            ipfs_status = response.status_code == 200
    except Exception:
        ipfs_status = False

    return {
        "status": "healthy" if ipfs_status else "degraded",
        "ipfs_connected": ipfs_status,
        "timestamp": datetime.utcnow().isoformat()
    }


@router.get("/api/v1/verify/{cid}")
async def verify_document(cid: str):
    """
    Verifiziert die Integrität eines Dokuments.
    Öffentlich zugänglich für Audit-Zwecke.

    - **cid**: Content Identifier (IPFS Hash)
    """
    try:
        content = await ipfs_cat(cid)
        package = json.loads(content)

        # Checksum verifizieren
        stored_checksum = package.get("metadata", {}).get("checksum")

        if "content_base64" in package:
            original_content = bytes.fromhex(package["content_base64"])
            calculated_checksum = hashlib.sha256(original_content).hexdigest()
        elif "content" in package:
            calculated_checksum = hashlib.sha256(
                package["content"].encode('utf-8')
            ).hexdigest()
        else:
            calculated_checksum = None

        integrity_valid = (
            stored_checksum == calculated_checksum
            if stored_checksum and calculated_checksum
            else None
        )

        return {
            "cid": cid,
            "exists": True,
            "integrity_valid": integrity_valid,
            "metadata": package.get("metadata", {}),
            "stored_checksum": stored_checksum,
            "calculated_checksum": calculated_checksum,
            "verified_at": datetime.utcnow().isoformat()
        }
    except Exception as e:
        return {
            "cid": cid,
            "exists": False,
            "error": str(e),
            "verified_at": datetime.utcnow().isoformat()
        }


@router.get("/api/v1/node/info")
async def get_node_info():
    """
    Gibt Informationen über den DSMS Node zurück.
    """
    try:
        async with httpx.AsyncClient(timeout=10.0) as client:
            # Node ID
            id_response = await client.post(f"{IPFS_API_URL}/api/v0/id")
            node_info = id_response.json() if id_response.status_code == 200 else {}

            # Repo Stats
            stat_response = await client.post(f"{IPFS_API_URL}/api/v0/repo/stat")
            repo_stats = stat_response.json() if stat_response.status_code == 200 else {}

            return {
                "node_id": node_info.get("ID"),
                "protocol_version": node_info.get("ProtocolVersion"),
                "agent_version": node_info.get("AgentVersion"),
                "repo_size": repo_stats.get("RepoSize"),
                "storage_max": repo_stats.get("StorageMax"),
                "num_objects": repo_stats.get("NumObjects"),
                "addresses": node_info.get("Addresses", [])[:5]  # Erste 5
            }
    except Exception as e:
        return {"error": str(e)}