package validators

import (
	"fmt"
	"os"
	"os/exec"
	"strings"

	"jagacloud/node-agent/pkg/compute/libvirt"
	"jagacloud/node-agent/pkg/config"
	"jagacloud/node-agent/pkg/containers/lxc"
)

// CheckBridge returns nil if the bridge exists on the host.
func CheckBridge(name string) error {
	if name == "" {
		return fmt.Errorf("bridge name required")
	}
	if os.Getenv("JAGACLOUD_SKIP_BRIDGE_CHECK") == "1" {
		return nil
	}
	if err := exec.Command("bash", "-lc", fmt.Sprintf("ip link show %s", name)).Run(); err != nil {
		return fmt.Errorf("bridge %s not found", name)
	}
	return nil
}

// CheckBridgeSet validates all bridges in NIC specs.
func CheckBridgeSet(nics []libvirt.NICSpec) error {
	for _, nic := range nics {
		if err := CheckBridge(nic.Bridge); err != nil {
			return err
		}
	}
	return nil
}

// CheckBridgeSetCT validates bridges for LXC NICs.
func CheckBridgeSetCT(nics []lxc.NICSpec) error {
	for _, nic := range nics {
		if err := CheckBridge(nic.Bridge); err != nil {
			return err
		}
	}
	return nil
}

// CheckStoragePool is a stub; implement LVM/ZFS/dir verification as needed.
func CheckStoragePool(name string) error {
	if name == "" {
		return fmt.Errorf("storage pool name required")
	}
	// TODO: query configured pools
	return nil
}

// CheckStoragePoolsVM ensures all disks reference known pools from config.
func CheckStoragePoolsVM(disks []libvirt.DiskSpec, cfg config.Config) error {
	for _, d := range disks {
		if d.Pool == "" {
			continue
		}
		if !poolExists(cfg, d.Pool) {
			return fmt.Errorf("storage pool %s not configured", d.Pool)
		}
	}
	return nil
}

// CheckStoragePoolsCT ensures rootfs pool exists.
func CheckStoragePoolsCT(spec lxc.Spec, cfg config.Config) error {
	if spec.RootfsPool != "" && !poolExists(cfg, spec.RootfsPool) {
		return fmt.Errorf("storage pool %s not configured", spec.RootfsPool)
	}
	return nil
}

// CheckStoragePoolsRuntime queries libvirt to see if pool exists; fallback to config.
func CheckStoragePoolsRuntime(pools []string, cfg config.Config) error {
	if len(pools) == 0 {
		return nil
	}
	for _, p := range pools {
		if p == "" {
			continue
		}
		if poolExists(cfg, p) {
			continue
		}
		// Try libvirt
		cmd := exec.Command("bash", "-lc", "virsh -q pool-list --name")
		out, err := cmd.Output()
		if err != nil {
			return fmt.Errorf("pool %s not found and virsh failed: %v", p, err)
		}
		found := false
		for _, line := range strings.Split(string(out), "\n") {
			if strings.TrimSpace(line) == p {
				found = true
				break
			}
		}
		if !found {
			return fmt.Errorf("storage pool %s not found", p)
		}
	}
	return nil
}

func poolExists(cfg config.Config, name string) bool {
	for _, p := range cfg.StoragePools {
		if p.Name == name {
			return true
		}
	}
	return false
}