package unpack

import (
	"fmt"

	"edge-infra.dev/pkg/f8n/warehouse/cluster"
	"edge-infra.dev/pkg/f8n/warehouse/oci/layer"
)

// Option is a functional option for unpacking pallets.
type Option func(*options)

func makeOptions(opts ...Option) (*options, error) {
	o := &options{}
	for _, opt := range opts {
		opt(o)
	}

	if len(o.keys) > 0 && len(o.types) > 0 {
		return nil, fmt.Errorf("options ForLayerKeys and ForLayerTypes are mutually " +
			"exclusive")
	}

	if o.infraNamespace != "" && !o.hasInfra() {
		return nil, fmt.Errorf("if WithInfraNamespace is provided, unpacking the " +
			"infrastructure layer must be enabled via ForLayerTypes or ForLayerKeys")
	}

	return o, nil
}

type options struct {
	infraNamespace string
	keys           []string
	types          []layer.Type
	provider       cluster.Provider
	render         bool
	parameters     []map[string]string
}

func (o *options) hasInfra() bool {
	for _, k := range o.keys {
		if k == layer.Infra.String() {
			return true
		}
	}
	for _, t := range o.types {
		if t == layer.Infra {
			return true
		}
	}
	return false
}

// WithInfraNamespace sets metadata.namespace field for all infrastructure
// objects.
func WithInfraNamespace(ns string) Option {
	return func(o *options) {
		o.infraNamespace = ns
	}
}

// ForProvider sets the cluster provider to unpack manifests for. This option
// must be provided if the artifact passed to Unpack isn't already a v1.Image or
// unwrap into one.
func ForProvider(p cluster.Provider) Option {
	return func(o *options) {
		o.provider = p
	}
}

// RenderWith merges the provided parameters with the already set parameters,
// last-in wins for duplicated keys. If this option is provided for unpacking a
// Pallet that isn't renderable, no action is taken.
func RenderWith(parameters ...map[string]string) Option {
	return func(o *options) {
		o.render = true
		o.parameters = parameters
	}
}

// ForLayerTypes returns the layers associated with the input layer types.
func ForLayerTypes(t ...layer.Type) Option {
	return func(o *options) {
		o.types = t
	}
}

// ForLayerKeys returns the layers with matching keys. See layer.Key().
func ForLayerKeys(s ...string) Option {
	return func(o *options) {
		o.keys = s
	}
}