file iterators refactored

builtin-os-file-iter-line.go

@@ -5,9 +5,6 @@
 package expr
 
 import (
-	"fmt"
-	"slices"
-
 	"git.portale-stac.it/go-pkg/expr/file"
 	"git.portale-stac.it/go-pkg/expr/kern"
 )
@@ -15,15 +12,15 @@ import (
 const fileLineIteratorType = "fileLineIterator"
 
 type fileFileLineIterator struct {
-	reader    *file.Reader
-	index     int64
-	count     int64
-	line      string
-	autoClose bool
+	fileIterBase
+	line string
 }
 
 func newFileLineIterator(r *file.Reader, autoClose bool) *fileFileLineIterator {
-	return &fileFileLineIterator{reader: r, index: -1, autoClose: autoClose}
+	return &fileFileLineIterator{
+		fileIterBase: fileIterBase{reader: r, index: -1, count: 0, autoClose: autoClose},
+		line:         "",
+	}
 }
 
 func (it *fileFileLineIterator) TypeName() string {
@@ -31,20 +28,12 @@ func (it *fileFileLineIterator) TypeName() string {
 }
 
 func (it *fileFileLineIterator) String() string {
-	if it.reader != nil && it.reader.GetFile() != nil {
-		return fmt.Sprintf("$(%s@%q)", fileLineIteratorType, it.reader.GetName())
-	}
-	return fmt.Sprintf("$(%s@<nil>)", fileLineIteratorType)
-}
-
-func (it *fileFileLineIterator) Count() int64 {
-	return it.count
+	return it.repr(fileLineIteratorType)
 }
 
 func (it *fileFileLineIterator) Next() (item any, err error) { // must return io.EOF after the last item
 	if it.line, err = it.reader.ReadString('\n'); err == nil {
-		it.index++
-		it.count++
+		it.increment()
 		item = it.line[0 : len(it.line)-1]
 	} else if it.autoClose {
 		it.Clean()
@@ -59,30 +48,23 @@ func (it *fileFileLineIterator) Current() (item any, err error) {
 	return
 }
 
-func (it *fileFileLineIterator) Index() int64 {
-	return it.index
-}
-
 func (it *fileFileLineIterator) Reset() (err error) {
 	if err = it.reader.Reset(); err == nil {
-		it.index = -1
-		it.count = 0
+		it.reset()
 		it.line = ""
 	}
 	return
 }
 
-func (it *fileFileLineIterator) HasOperation(name string) bool {
-	return slices.Contains([]string{kern.NextName, kern.ResetName, kern.IndexName, kern.CountName, kern.CurrentName, kern.CleanName}, name)
-}
-
 func (it *fileFileLineIterator) Clean() (err error) {
 	if it.reader != nil {
 		if err = it.reader.Close(); err == nil {
 			it.reader = nil
 		}
 	}
-	return nil
+	it.reset()
+	it.line = ""
+	return
 }
 
 func (it *fileFileLineIterator) CallOperation(name string, args map[string]any) (v any, err error) {
@@ -110,26 +92,6 @@ func fileLineIteratorFunc(ctx kern.ExprContext, name string, args map[string]any
 	var invalidFileHandle any
 	var autoClose bool
 
-	result = nil
-	// if handle, ok = args[paramHandleOrPath].(*osReader); !ok {
-	// 	if fileName, ok := args[paramHandleOrPath].(string); ok && len(fileName) > 0 {
-	// 		var handleAny any
-	// 		if handleAny, err = openFileFunc(ctx, name, map[string]any{kern.ParamFilepath: fileName}); err != nil {
-	// 			return
-	// 		}
-	// 		if handleAny != nil {
-	// 			handle = handleAny.(*osReader)
-	// 			autoClose = true
-	// 		}
-	// 	} else {
-	// 		invalidFileHandle = args[paramHandleOrPath]
-	// 	}
-	// }
-
-	// if handle != nil {
-	// 	result = newFileLineIterator(handle, autoClose)
-	// }
-
 	if handle, invalidFileHandle, autoClose, err = initFileHandle(ctx, name, args); err == nil {
 		if handle != nil {
 			result = newFileLineIterator(handle, autoClose)