decoder [WIP]

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

decoder.go

@@ -0,0 +1,74 @@
+package ini
+
+import (
+	"bytes"
+	"io"
+	"strings"
+
+	"asciigoat.org/core"
+	"asciigoat.org/core/reflection"
+	"asciigoat.org/ini/parser"
+)
+
+// Decoder ...
+type Decoder[T any] struct {
+	io.Closer
+
+	out *reflection.Reflection[T]
+	p   *parser.Parser
+}
+
+// Decode ...
+func (dec *Decoder[T]) Decode(v *T) error {
+	defer dec.Close()
+
+	r, err := reflection.New(v)
+	switch e := err.(type) {
+	case *reflection.InvalidUnmarshalError:
+		// customize error
+		e.Prefix = "ini"
+		e.Method = "Decode"
+		return e
+	case nil:
+		// good reflection. Go!
+		dec.out = r
+		return dec.p.Run()
+	default:
+		// other errors
+		panic("unreachable")
+	}
+
+}
+
+// NewDecoder creates a Decoder using the provided [io.Reader]
+// as source
+func NewDecoder[T any](r io.Reader) *Decoder[T] {
+	rc := core.NewReadCloser(r)
+	switch {
+	case rc == nil:
+		return nil
+	default:
+		dec := &Decoder[T]{
+			p:      parser.NewParser(rc),
+			Closer: rc,
+		}
+		dec.init()
+		return dec
+	}
+}
+
+func (dec *Decoder[T]) init() {
+	dec.p.OnToken = dec.parserOnToken
+	dec.p.OnError = dec.parserOnError
+}
+
+// NewDecoderBytes creates a Decoder using the provided bytes array
+// as source
+func NewDecoderBytes[T any](b []byte) *Decoder[T] {
+	return NewDecoder[T](bytes.NewReader(b))
+}
+
+// NewDecoderString creates a Decoder over a provided string of data
+func NewDecoderString[T any](s string) *Decoder[T] {
+	return NewDecoder[T](strings.NewReader(s))
+}

decoder_error.go

@@ -0,0 +1,18 @@
+package ini
+
+import (
+	"log"
+
+	"asciigoat.org/core/lexer"
+)
+
+func (*Decoder[T]) parserOnError(pos lexer.Position, content string, err error) error {
+	log.Printf("%s: %s %s: %q: %v", "ini", pos, "error:", content, err)
+
+	return &lexer.Error{
+		Line:    pos.Line,
+		Column:  pos.Column,
+		Content: content,
+		Err:     err,
+	}
+}

decoder_token.go

@@ -0,0 +1,14 @@
+package ini
+
+import (
+	"log"
+
+	"asciigoat.org/core/lexer"
+	"asciigoat.org/ini/parser"
+)
+
+func (*Decoder[T]) parserOnToken(pos lexer.Position, typ parser.TokenType, value string) error {
+	log.Printf("%s: %s %s %q", "ini", pos, typ, value)
+
+	return nil
+}