reencode: Factor into separate modules

1 files changed, 52 insertions, 0 deletions

diff --git a/reencode_write.go b/reencode_write.go
new file mode 100644
index 0000000..dffbb21
--- /dev/null
+++ b/reencode_write.go
@@ -0,0 +1,52 @@
+// Copyright (C) 2022-2023  Luke Shumaker <lukeshu@lukeshu.com>
+//
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+package lowmemjson
+
+import (
+	"git.lukeshu.com/go/lowmemjson/internal/fastio"
+	"git.lukeshu.com/go/lowmemjson/internal/jsonparse"
+	"git.lukeshu.com/go/lowmemjson/internal/jsonstring"
+)
+
+type reEncodeWrite struct {
+	out fastio.AllWriter
+
+	// state
+	last       jsonparse.RuneType
+	lastNonEOF jsonparse.RuneType
+	wasNumber  bool
+}
+
+var _ reEncoderModule = (*reEncodeWrite)(nil)
+
+func (enc *reEncodeWrite) PopWriteBarrier() {
+	enc.last = enc.lastNonEOF
+}
+
+func (enc *reEncodeWrite) HandleRune(c rune, t jsonparse.RuneType, escape BackslashEscapeMode, _ int) error {
+	// emit newlines between top-level values, if nescessary
+	if enc.last == jsonparse.RuneTypeEOF && enc.wasNumber && t.IsNumber() {
+		if _, err := enc.out.WriteRune('\n'); err != nil {
+			return err
+		}
+	}
+	if t == jsonparse.RuneTypeEOF {
+		enc.wasNumber = enc.last.IsNumber()
+	} else {
+		enc.lastNonEOF = t
+	}
+	enc.last = t
+
+	// emit the rune
+	switch t {
+	case jsonparse.RuneTypeEOF:
+		return nil
+	case jsonparse.RuneTypeStringChar:
+		return jsonstring.WriteStringChar(enc.out, c, escape)
+	default:
+		_, err := enc.out.WriteRune(c)
+		return err
+	}
+}