package app

import (
	"net/http"
)

func handleTransportClientLifecycleAction(w http.ResponseWriter, r *http.Request, id, action string) {
	if r.Method != http.MethodPost {
		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
		return
	}

	lockIDs, ok := resolveTransportLifecycleLockIDs(id, action)
	if !ok {
		writeJSON(w, http.StatusNotFound, TransportClientLifecycleResponse{
			OK:      false,
			Message: "not found",
			Code:    "TRANSPORT_CLIENT_NOT_FOUND",
		})
		return
	}

	status := http.StatusOK
	resp := TransportClientLifecycleResponse{}
	withTransportIfaceLocks(lockIDs, func() {
		status, resp = executeTransportLifecycleActionWithPreflightLocked(id, action)
	})
	writeJSON(w, status, resp)
}

func executeTransportLifecycleActionWithPreflightLocked(id, action string) (int, TransportClientLifecycleResponse) {
	if preStatus, preResp, handled := runTransportLifecyclePreflight(id, action); handled {
		return preStatus, preResp
	}
	return executeTransportLifecycleActionLocked(id, action)
}

func resolveTransportLifecycleLockIDsForSnapshot(items []TransportClient, ifaces transportInterfacesState, id, action string) ([]string, bool) {
	idx := findTransportClientIndex(items, id)
	if idx < 0 {
		return nil, false
	}
	targetBinding := resolveTransportIfaceBinding(items[idx], ifaces)
	lockIDs := []string{targetBinding.IfaceID}
	if action == "start" || action == "restart" {
		_, peers := matchTransportSingBoxPeersInSameNetnsForLock(items, idx, ifaces)
		for _, peer := range peers {
			lockIDs = append(lockIDs, peer.Binding.IfaceID)
		}
	}
	return lockIDs, true
}

func resolveTransportLifecycleLockIDs(id, action string) ([]string, bool) {
	transportMu.Lock()
	clientsState := loadTransportClientsState()
	idx := findTransportClientIndex(clientsState.Items, id)
	if idx < 0 {
		transportMu.Unlock()
		return nil, false
	}
	ifacesState := loadTransportInterfacesState()
	ifacesSnapshot := captureTransportInterfacesStateSnapshot(clientsState, ifacesState)
	transportMu.Unlock()

	normIfaces, changed := normalizeTransportInterfacesState(ifacesState, clientsState.Items)
	if changed {
		_ = saveTransportInterfacesIfSnapshotCurrent(ifacesSnapshot, normIfaces)
	}

	return resolveTransportLifecycleLockIDsForSnapshot(clientsState.Items, normIfaces, id, action)
}