chore: refactor plugin structure (#18335)

plugin/map.go

@@ -0,0 +1,77 @@
+package plugin
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/evcc-io/evcc/util"
+)
+
+type mapPlugin struct {
+	ctx      context.Context
+	values   map[int64]int64
+	get, set Config
+}
+
+func init() {
+	registry.AddCtx("map", NewMapFromConfig)
+}
+
+// NewMapFromConfig creates type conversion provider
+func NewMapFromConfig(ctx context.Context, other map[string]interface{}) (Plugin, error) {
+	var cc struct {
+		Values   map[int64]int64
+		Get, Set Config
+	}
+
+	if err := util.DecodeOther(other, &cc); err != nil {
+		return nil, err
+	}
+
+	if len(cc.Values) == 0 {
+		return nil, fmt.Errorf("missing values")
+	}
+
+	o := &mapPlugin{
+		ctx:    ctx,
+		get:    cc.Get,
+		set:    cc.Set,
+		values: cc.Values,
+	}
+
+	return o, nil
+}
+
+var _ IntGetter = (*mapPlugin)(nil)
+
+func (o *mapPlugin) IntGetter() (func() (int64, error), error) {
+	get, err := o.get.IntGetter(o.ctx)
+
+	return func() (int64, error) {
+		val, err := get()
+		if err != nil {
+			return 0, err
+		}
+
+		res, ok := o.values[val]
+		if !ok {
+			return 0, fmt.Errorf("map: value not found: %d", val)
+		}
+
+		return res, nil
+	}, err
+}
+
+var _ IntSetter = (*mapPlugin)(nil)
+
+func (o *mapPlugin) IntSetter(param string) (func(int64) error, error) {
+	set, err := o.set.IntSetter(o.ctx, param)
+
+	return func(val int64) error {
+		m, ok := o.values[val]
+		if !ok {
+			return fmt.Errorf("map: value not found: %d", val)
+		}
+		return set(m)
+	}, err
+}