from typing import Any, Dict, List, Optional

import httpx

from app.core.config import get_settings
from app.models.schemas import ProxmoxServerConfig, ServerScanStatus, VmRecord
from app.services.metadata import extract_duplicate_id


class ProxmoxClient:
    def __init__(self, server: ProxmoxServerConfig):
        self.server = server
        self.base_url = str(server.url).rstrip("/")
        self.errors: List[str] = []

    async def __aenter__(self) -> "ProxmoxClient":
        settings = get_settings()
        self.client = httpx.AsyncClient(
            base_url=f"{self.base_url}/api2/json",
            headers={
                "Authorization": (
                    f"PVEAPIToken={self.server.token_name}={self.server.token_value}"
                )
            },
            timeout=settings.PROXMOX_TIMEOUT,
            verify=settings.PROXMOX_VERIFY_SSL,
        )
        return self

    async def __aexit__(self, exc_type, exc, tb) -> None:
        await self.client.aclose()

    async def scan(self) -> tuple[ServerScanStatus, List[VmRecord]]:
        items = await self._scan_nodes()
        if not items:
            fallback_items = await self._scan_cluster_resources()
            items.extend(fallback_items)
            if not items and await self._has_no_effective_permissions():
                self.errors.append(
                    "permissions effectives vides pour ce token; Proxmox filtre probablement les VM/LXC"
                )

        status = ServerScanStatus(
            name=self.server.name,
            url=self.base_url,
            ok=not self.errors or bool(items),
            vm_count=len(items),
            errors=self.errors,
        )
        return status, items

    async def _has_no_effective_permissions(self) -> bool:
        permissions = await self._get_data("/access/permissions?path=/", optional=True)
        if not isinstance(permissions, dict):
            return False
        if not permissions:
            return True
        return all(not value for value in permissions.values())

    async def _get_data(self, path: str, *, optional: bool = False) -> Optional[Any]:
        try:
            response = await self.client.get(path)
            response.raise_for_status()
            payload = response.json()
        except httpx.HTTPStatusError as exc:
            message = self._format_http_error(path, exc)
            if optional and exc.response.status_code in {401, 403, 404}:
                return None
            self.errors.append(message)
            return None
        except httpx.HTTPError as exc:
            self.errors.append(f"{path}: {exc}")
            return None
        except ValueError:
            self.errors.append(f"{path}: réponse JSON invalide")
            return None

        return payload.get("data")

    def _format_http_error(self, path: str, exc: httpx.HTTPStatusError) -> str:
        detail = exc.response.text.strip()
        if len(detail) > 160:
            detail = f"{detail[:157]}..."
        return f"{path}: HTTP {exc.response.status_code} {detail}".strip()

    async def _scan_nodes(self) -> List[VmRecord]:
        nodes = await self._get_data("/nodes")
        if not isinstance(nodes, list):
            return []

        items: List[VmRecord] = []
        for node in nodes:
            node_name = node.get("node")
            if not node_name:
                continue
            items.extend(await self._scan_node_vms(node_name, "qemu"))
            items.extend(await self._scan_node_vms(node_name, "lxc"))
        return items

    async def _scan_node_vms(self, node: str, vm_type: str) -> List[VmRecord]:
        path = f"/nodes/{node}/{vm_type}"
        records = await self._get_data(path)
        if not isinstance(records, list):
            return []

        items = []
        for record in records:
            vmid = record.get("vmid")
            if vmid is None:
                continue
            config = await self._get_data(
                f"{path}/{vmid}/config",
                optional=True,
            )
            items.append(self._to_vm_record(node, vm_type, record, config))
        return items

    async def _scan_cluster_resources(self) -> List[VmRecord]:
        resources = await self._get_data("/cluster/resources?type=vm")
        if not isinstance(resources, list):
            return []

        items = []
        for resource in resources:
            vm_type = resource.get("type")
            if vm_type not in {"qemu", "lxc"}:
                continue
            node = resource.get("node") or "unknown"
            items.append(self._to_vm_record(node, vm_type, resource, None))
        return items

    def _to_vm_record(
        self,
        node: str,
        vm_type: str,
        record: Dict[str, Any],
        config: Optional[Dict[str, Any]],
    ) -> VmRecord:
        vmid = int(record["vmid"])
        description = None
        tags = record.get("tags")
        if isinstance(config, dict):
            description = config.get("description")
            tags = config.get("tags", tags)

        return VmRecord(
            id=f"{self.server.name}:{node}:{vm_type}:{vmid}",
            server=self.server.name,
            node=node,
            vmid=vmid,
            type=vm_type,
            name=record.get("name") or record.get("hostname") or f"{vm_type}-{vmid}",
            status=record.get("status"),
            cpu=record.get("cpu"),
            mem=record.get("mem"),
            maxmem=record.get("maxmem"),
            disk=record.get("disk"),
            maxdisk=record.get("maxdisk"),
            uptime=record.get("uptime"),
            tags=tags,
            duplicate_id=extract_duplicate_id(description),
            description_available=description is not None,
            raw=record,
        )