Nexus/server/api/servers.py

"""Nexus — Servers API Routes (CRUD + heartbeat + health check + push)
Presentation layer — receives HTTP requests, delegates to ServerService/SyncService.

Live server status comes from Redis (real-time), base info from MySQL.
"""

import json
import logging
from typing import Optional, List

from fastapi import APIRouter, Depends, HTTPException, Query

from server.api.dependencies import get_server_service, get_sync_service, get_db
from server.api.auth_jwt import get_current_admin
from server.api.schemas import ServerCreate, ServerUpdate, ServerPush, ServerCheck
from server.application.services.server_service import ServerService
from server.application.services.sync_service import SyncService
from server.domain.models import Server, SyncLog, Admin
from server.infrastructure.redis.client import get_redis

from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

logger = logging.getLogger("nexus.servers")

router = APIRouter(prefix="/api/servers", tags=["servers"])

REDIS_KEY_PREFIX = "heartbeat:"


# ── CRUD ──

@router.get("/", response_model=dict)
async def list_servers(
    category: Optional[str] = Query(None, description="Filter by category"),
    page: int = Query(1, ge=1, description="Page number"),
    per_page: int = Query(50, ge=1, le=200, description="Items per page"),
    service: ServerService = Depends(get_server_service),
):
    """List servers with live status from Redis (paginated)

    Base info (name/IP/category) from MySQL, real-time status from Redis.
    If Redis heartbeat key exists, override is_online/system_info/last_heartbeat.
    """
    servers = await service.list_servers(category)
    redis = get_redis()

    total = len(servers)
    start = (page - 1) * per_page
    end = start + per_page
    page_servers = servers[start:end]

    result = []
    for server in page_servers:
        server_data = _server_to_dict(server)

        # Overlay Redis heartbeat data (real-time)
        try:
            heartbeat = await redis.hgetall(f"{REDIS_KEY_PREFIX}{server.id}")
            if heartbeat:
                server_data["is_online"] = heartbeat.get("is_online") == "True"
                if heartbeat.get("system_info"):
                    try:
                        server_data["system_info"] = json.loads(heartbeat.get("system_info", "{}"))
                    except (json.JSONDecodeError, TypeError):
                        pass  # Keep MySQL value
                server_data["last_heartbeat"] = heartbeat.get("last_heartbeat", server_data.get("last_heartbeat"))
                server_data["agent_version"] = heartbeat.get("agent_version", server_data.get("agent_version", ""))
                server_data["_source"] = "redis"
        except Exception as e:
            logger.warning(f"Redis read failed for server {server.id}: {e}")

        result.append(server_data)

    return {
        "items": result,
        "total": total,
        "page": page,
        "per_page": per_page,
        "pages": (total + per_page - 1) // per_page,
    }


# ── Dashboard Stats (must be before /{id} to avoid path collision) ──

@router.get("/stats", response_model=dict)
async def server_stats(
    service: ServerService = Depends(get_server_service),
):
    """Aggregated server stats for dashboard — efficient single query"""
    servers = await service.list_servers()
    redis = get_redis()

    total = len(servers)
    online = 0
    offline = 0
    alerts = 0

    for server in servers:
        try:
            heartbeat = await redis.hgetall(f"{REDIS_KEY_PREFIX}{server.id}")
            is_online = heartbeat.get("is_online") == "True" if heartbeat else server.is_online
            if await redis.exists(f"alerts:{server.id}"):
                alerts += 1
        except Exception:
            is_online = server.is_online
        if is_online:
            online += 1
        else:
            offline += 1

    categories = {}
    for server in servers:
        cat = server.category or "uncategorized"
        categories[cat] = categories.get(cat, 0) + 1

    return {
        "total": total,
        "online": online,
        "offline": offline,
        "alerts": alerts,
        "categories": categories,
    }


@router.get("/{id}", response_model=dict)
async def get_server(
    id: int,
    service: ServerService = Depends(get_server_service),
):
    """Get a single server by ID with live status from Redis"""
    server = await service.get_server(id)
    if not server:
        raise HTTPException(status_code=404, detail="Server not found")

    server_data = _server_to_dict(server)

    # Overlay Redis heartbeat data
    redis = get_redis()
    try:
        heartbeat = await redis.hgetall(f"{REDIS_KEY_PREFIX}{id}")
        if heartbeat:
            server_data["is_online"] = heartbeat.get("is_online") == "True"
            if heartbeat.get("system_info"):
                try:
                    server_data["system_info"] = json.loads(heartbeat.get("system_info", "{}"))
                except (json.JSONDecodeError, TypeError):
                    pass
            server_data["last_heartbeat"] = heartbeat.get("last_heartbeat", server_data.get("last_heartbeat"))
            server_data["agent_version"] = heartbeat.get("agent_version", server_data.get("agent_version", ""))
            server_data["_source"] = "redis"
    except Exception as e:
        logger.warning(f"Redis read failed for server {id}: {e}")

    return server_data


@router.post("/", response_model=dict, status_code=201)
async def create_server(
    payload: ServerCreate,
    service: ServerService = Depends(get_server_service),
):
    """Create a new server"""
    server = Server(**payload.model_dump(exclude_none=True))
    created = await service.create_server(server)
    return _server_to_dict(created)


@router.put("/{id}", response_model=dict)
async def update_server(
    id: int,
    payload: ServerUpdate,
    service: ServerService = Depends(get_server_service),
):
    """Update an existing server"""
    server = await service.get_server(id)
    if not server:
        raise HTTPException(status_code=404, detail="Server not found")
    for key, value in payload.model_dump(exclude_unset=True).items():
        if hasattr(server, key) and key != "id":
            setattr(server, key, value)
    updated = await service.update_server(server)
    return _server_to_dict(updated)


@router.delete("/{id}", status_code=204)
async def delete_server(
    id: int,
    service: ServerService = Depends(get_server_service),
):
    """Delete a server"""
    result = await service.delete_server(id)
    if not result:
        raise HTTPException(status_code=404, detail="Server not found")


# ── Health Check ──

@router.post("/check", response_model=dict)
async def check_servers(
    payload: ServerCheck,
    service: ServerService = Depends(get_server_service),
):
    """Check health status of specified servers (Agent-based, no SSH)"""
    return await service.check_all_servers(payload.server_ids)


# ── Push ──

@router.post("/push", response_model=dict)
async def push_to_servers(
    payload: ServerPush,
    admin: Admin = Depends(get_current_admin),
    sync_service: SyncService = Depends(get_sync_service),
):
    """Push files to multiple servers (batch mode with concurrency control)"""
    results = await sync_service.batch_push(
        server_ids=payload.server_ids,
        source_path=payload.source_path,
        sync_mode=payload.sync_mode,
        operator=admin.username,
        batch_size=payload.batch_size,
        concurrency=payload.concurrency,
    )
    return {sid: _sync_log_to_dict(log) for sid, log in results.items()}


# ── Sync Logs ──

@router.get("/logs", response_model=list)
async def get_all_sync_logs(
    limit: int = Query(100, ge=1, le=500),
    db: AsyncSession = Depends(get_db),
):
    """Get recent sync logs across all servers (for dashboard charts)"""
    result = await db.execute(
        select(SyncLog).order_by(SyncLog.started_at.desc()).limit(limit)
    )
    logs = result.scalars().all()
    return [_sync_log_to_dict(log) for log in logs]


@router.get("/{id}/logs", response_model=list)
async def get_server_logs(
    id: int,
    limit: int = Query(50, ge=1, le=200),
    sync_service: SyncService = Depends(get_sync_service),
):
    """Get sync logs for a specific server"""
    logs = await sync_service.get_sync_logs(id, limit)
    return [_sync_log_to_dict(log) for log in logs]


# ── Helper functions ──

def _server_to_dict(server: Server) -> dict:
    """Convert Server model to API response dict (hide sensitive fields)"""
    return {
        "id": server.id,
        "name": server.name,
        "domain": server.domain,
        "port": server.port,
        "username": server.username,
        "auth_method": server.auth_method,
        "agent_port": server.agent_port,
        "description": server.description,
        "target_path": server.target_path,
        "category": server.category,
        "platform_id": server.platform_id,
        "node_id": server.node_id,
        "protocols": server.protocols,
        "extra_attrs": server.extra_attrs,
        "connectivity": server.connectivity,
        "ssh_key_configured": server.ssh_key_configured,
        "is_online": server.is_online,
        "last_heartbeat": str(server.last_heartbeat) if server.last_heartbeat else None,
        "system_info": server.system_info,
        "agent_version": server.agent_version,
        "created_at": str(server.created_at) if server.created_at else None,
        "updated_at": str(server.updated_at) if server.updated_at else None,
    }


def _sync_log_to_dict(log) -> dict:
    """Convert SyncLog model to API response dict"""
    return {
        "id": log.id,
        "server_id": log.server_id,
        "source_path": log.source_path,
        "target_path": log.target_path,
        "trigger_type": log.trigger_type,
        "operator": log.operator,
        "status": log.status,
        "sync_mode": log.sync_mode,
        "files_total": log.files_total,
        "files_transferred": log.files_transferred,
        "duration_seconds": log.duration_seconds,
        "error_message": log.error_message,
        "started_at": str(log.started_at) if log.started_at else None,
        "finished_at": str(log.finished_at) if log.finished_at else None,
    }