basic: GoString [WIP]

Signed-off-by: Alejandro Mery <amery@jpi.io>

basic/basic.go

@@ -1,2 +1,24 @@
 // Package basic provides a basic representation of dosini-style documents
 package basic
+
+// Document represents an INI-style document
+type Document struct {
+	Global []Field
+
+	Sections []Section
+}
+
+// Section represents an INI-style section with optional GIT-style IDs
+type Section struct {
+	Key     string
+	ID      string
+	EmptyID bool
+
+	Fields []Field
+}
+
+// Field represents a key = value entry in an INI-style document
+type Field struct {
+	Key   string
+	Value string
+}

basic/token.go

@@ -50,15 +50,17 @@ func (dec *decoder) execute(typ parser.TokenType) {
 	}
 }
 
-func (dec *decoder) addSection(name, key string, hadKey bool) {
+func (dec *decoder) addSection(key, id string, allowEmptyID bool) {
+	emptyID := allowEmptyID && id == ""
+
 	// index for dec.current
 	n := len(dec.out.Sections)
 
 	// new section
 	dec.out.Sections = append(dec.out.Sections, Section{
-		Name:   name,
+		Key:     key,
-		Key:    key,
+		ID:      id,
-		HadKey: hadKey,
+		EmptyID: emptyID,
 	})
 
 	// pointer to the latest section

basic/types.go

@@ -1,23 +0,0 @@
-package basic
-
-// Document ...
-type Document struct {
-	Global []Field
-
-	Sections []Section
-}
-
-// Section ...
-type Section struct {
-	Name   string
-	Key    string
-	HadKey bool
-
-	Fields []Field
-}
-
-// Field ...
-type Field struct {
-	Key   string
-	Value string
-}

basic/write.go

@@ -0,0 +1,94 @@
+package basic
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+
+	"asciigoat.org/ini/parser"
+)
+
+// WriteNewLine is the new line representation used by [doc.WriteTo]
+const WriteNewLine = "\n"
+
+// AsBuffer returns a INI representation of the document on
+// a memory buffer
+func (doc *Document) AsBuffer(nl string) *bytes.Buffer {
+	var buf bytes.Buffer
+
+	if len(doc.Global) > 0 {
+		_, _ = writeFieldsTo(&buf, doc.Global, nl)
+	}
+
+	for _, sec := range doc.Sections {
+		if buf.Len() > 0 {
+			_, _ = buf.WriteString(nl)
+		}
+
+		_ = writeSectionToBuffer(&buf, &sec, nl)
+	}
+
+	return &buf
+}
+
+func writeFieldsTo(w io.Writer, fields []Field, nl string) (int64, error) {
+	var written int
+	for _, field := range fields {
+		n, err := fmt.Fprintf(w, "%s = %q%s", field.Key, field.Value, nl)
+		switch {
+		case err != nil:
+			return int64(written), err
+		case n > 0:
+			written += n
+		}
+	}
+	return int64(written), nil
+}
+
+func writeSectionToBuffer(w *bytes.Buffer, sec *Section, nl string) int {
+	var written, n int
+
+	_, _ = w.WriteRune(parser.RuneSectionStart)
+	written++
+
+	n, _ = w.WriteString(sec.Key)
+	written += n
+
+	switch {
+	case sec.EmptyID:
+		n, _ = w.WriteString(" \"\"")
+		written += n
+	case sec.ID != "":
+		_, _ = w.WriteRune(' ')
+		n, _ = fmt.Fprintf(w, "%q", sec.ID)
+		written += n + 1
+	}
+
+	_, _ = w.WriteRune(parser.RuneSectionEnd)
+	written++
+
+	n, _ = w.WriteString(nl)
+	written += n
+
+	n64, _ := writeFieldsTo(w, sec.Fields, nl)
+	return written + int(n64)
+}
+
+// WriteTo writes a INI representation of the document
+// onto the provided writer.
+func (doc *Document) WriteTo(w io.Writer) (int64, error) {
+	buf := doc.AsBuffer(WriteNewLine)
+	return buf.WriteTo(w)
+}
+
+// GoString generates a string output for "%s"
+func (doc *Document) String() string {
+	buf := doc.AsBuffer(WriteNewLine)
+	return buf.String()
+}
+
+// GoString generates a string output for "%#v"
+func (Document) GoString() string {
+	var buf bytes.Buffer
+	return buf.String()
+}