refactor: restructure codebase to internal/ directory with modular architecture

- Move all source files to internal/{app,backend,config,executor,logger,parser,utils}
- Integrate third-party libraries: zerolog, goccy/go-json, gopsutil, cobra/viper
- Add comprehensive unit tests for utils package (94.3% coverage)
- Add performance benchmarks for string operations
- Fix error display: cleanup warnings no longer pollute Recent Errors
- Add GitHub Actions CI workflow
- Add Makefile for build automation
- Add README documentation

Generated with SWE-Agent.ai

Co-Authored-By: SWE-Agent.ai <noreply@swe-agent.ai>

codeagent-wrapper/internal/parser/event.go

@@ -0,0 +1,74 @@
+package parser
+
+import "github.com/goccy/go-json"
+
+// JSONEvent represents a Codex JSON output event.
+type JSONEvent struct {
+	Type     string     `json:"type"`
+	ThreadID string     `json:"thread_id,omitempty"`
+	Item     *EventItem `json:"item,omitempty"`
+}
+
+// EventItem represents the item field in a JSON event.
+type EventItem struct {
+	Type string      `json:"type"`
+	Text interface{} `json:"text"`
+}
+
+// ClaudeEvent for Claude stream-json format.
+type ClaudeEvent struct {
+	Type      string `json:"type"`
+	Subtype   string `json:"subtype,omitempty"`
+	SessionID string `json:"session_id,omitempty"`
+	Result    string `json:"result,omitempty"`
+}
+
+// GeminiEvent for Gemini stream-json format.
+type GeminiEvent struct {
+	Type      string `json:"type"`
+	SessionID string `json:"session_id,omitempty"`
+	Role      string `json:"role,omitempty"`
+	Content   string `json:"content,omitempty"`
+	Delta     bool   `json:"delta,omitempty"`
+	Status    string `json:"status,omitempty"`
+}
+
+// UnifiedEvent combines all backend event formats into a single structure
+// to avoid multiple JSON unmarshal operations per event.
+type UnifiedEvent struct {
+	// Common fields
+	Type string `json:"type"`
+
+	// Codex-specific fields
+	ThreadID string          `json:"thread_id,omitempty"`
+	Item     json.RawMessage `json:"item,omitempty"` // Lazy parse
+
+	// Claude-specific fields
+	Subtype   string `json:"subtype,omitempty"`
+	SessionID string `json:"session_id,omitempty"`
+	Result    string `json:"result,omitempty"`
+
+	// Gemini-specific fields
+	Role    string `json:"role,omitempty"`
+	Content string `json:"content,omitempty"`
+	Delta   *bool  `json:"delta,omitempty"`
+	Status  string `json:"status,omitempty"`
+
+	// Opencode-specific fields (camelCase sessionID)
+	OpencodeSessionID string          `json:"sessionID,omitempty"`
+	Part              json.RawMessage `json:"part,omitempty"`
+}
+
+// OpencodePart represents the part field in opencode events.
+type OpencodePart struct {
+	Type      string `json:"type"`
+	Text      string `json:"text,omitempty"`
+	Reason    string `json:"reason,omitempty"`
+	SessionID string `json:"sessionID,omitempty"`
+}
+
+// ItemContent represents the parsed item.text field for Codex events.
+type ItemContent struct {
+	Type string      `json:"type"`
+	Text interface{} `json:"text"`
+}

codeagent-wrapper/internal/parser/parser.go

@@ -0,0 +1,436 @@
+package parser
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"strings"
+	"sync"
+
+	"github.com/goccy/go-json"
+)
+
+const (
+	jsonLineReaderSize   = 64 * 1024
+	jsonLineMaxBytes     = 10 * 1024 * 1024
+	jsonLinePreviewBytes = 256
+)
+
+type lineScratch struct {
+	buf     []byte
+	preview []byte
+}
+
+const maxPooledLineScratchCap = 1 << 20 // 1 MiB
+
+var lineScratchPool = sync.Pool{
+	New: func() any {
+		return &lineScratch{
+			buf:     make([]byte, 0, jsonLineReaderSize),
+			preview: make([]byte, 0, jsonLinePreviewBytes),
+		}
+	},
+}
+
+func ParseJSONStreamInternal(r io.Reader, warnFn func(string), infoFn func(string), onMessage func(), onComplete func()) (message, threadID string) {
+	reader := bufio.NewReaderSize(r, jsonLineReaderSize)
+	scratch := lineScratchPool.Get().(*lineScratch)
+	if scratch.buf == nil {
+		scratch.buf = make([]byte, 0, jsonLineReaderSize)
+	} else {
+		scratch.buf = scratch.buf[:0]
+	}
+	if scratch.preview == nil {
+		scratch.preview = make([]byte, 0, jsonLinePreviewBytes)
+	} else {
+		scratch.preview = scratch.preview[:0]
+	}
+	defer func() {
+		if cap(scratch.buf) > maxPooledLineScratchCap {
+			scratch.buf = nil
+		} else if scratch.buf != nil {
+			scratch.buf = scratch.buf[:0]
+		}
+		if cap(scratch.preview) > jsonLinePreviewBytes*4 {
+			scratch.preview = nil
+		} else if scratch.preview != nil {
+			scratch.preview = scratch.preview[:0]
+		}
+		lineScratchPool.Put(scratch)
+	}()
+
+	if warnFn == nil {
+		warnFn = func(string) {}
+	}
+	if infoFn == nil {
+		infoFn = func(string) {}
+	}
+
+	notifyMessage := func() {
+		if onMessage != nil {
+			onMessage()
+		}
+	}
+
+	notifyComplete := func() {
+		if onComplete != nil {
+			onComplete()
+		}
+	}
+
+	totalEvents := 0
+
+	var (
+		codexMessage    string
+		claudeMessage   string
+		geminiBuffer    strings.Builder
+		opencodeMessage strings.Builder
+	)
+
+	for {
+		line, tooLong, err := readLineWithLimit(reader, jsonLineMaxBytes, jsonLinePreviewBytes, scratch)
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				break
+			}
+			warnFn("Read stdout error: " + err.Error())
+			break
+		}
+
+		line = bytes.TrimSpace(line)
+		if len(line) == 0 {
+			continue
+		}
+		totalEvents++
+
+		if tooLong {
+			warnFn(fmt.Sprintf("Skipped overlong JSON line (> %d bytes): %s", jsonLineMaxBytes, TruncateBytes(line, 100)))
+			continue
+		}
+
+		// Single unmarshal for all backend types
+		var event UnifiedEvent
+		if err := json.Unmarshal(line, &event); err != nil {
+			warnFn(fmt.Sprintf("Failed to parse event: %s", TruncateBytes(line, 100)))
+			continue
+		}
+
+		// Detect backend type by field presence
+		isCodex := event.ThreadID != ""
+		if !isCodex && len(event.Item) > 0 {
+			var itemHeader struct {
+				Type string `json:"type"`
+			}
+			if json.Unmarshal(event.Item, &itemHeader) == nil && itemHeader.Type != "" {
+				isCodex = true
+			}
+		}
+		// Codex-specific event types without thread_id or item
+		if !isCodex && (event.Type == "turn.started" || event.Type == "turn.completed") {
+			isCodex = true
+		}
+		isClaude := event.Subtype != "" || event.Result != ""
+		if !isClaude && event.Type == "result" && event.SessionID != "" && event.Status == "" {
+			isClaude = true
+		}
+		isGemini := (event.Type == "init" && event.SessionID != "") || event.Role != "" || event.Delta != nil || event.Status != ""
+		isOpencode := event.OpencodeSessionID != "" && len(event.Part) > 0
+
+		// Handle Opencode events first (most specific detection)
+		if isOpencode {
+			if threadID == "" {
+				threadID = event.OpencodeSessionID
+			}
+
+			var part OpencodePart
+			if err := json.Unmarshal(event.Part, &part); err != nil {
+				warnFn(fmt.Sprintf("Failed to parse opencode part: %s", err.Error()))
+				continue
+			}
+
+			// Extract sessionID from part if available
+			if part.SessionID != "" && threadID == "" {
+				threadID = part.SessionID
+			}
+
+			infoFn(fmt.Sprintf("Parsed Opencode event #%d type=%s part_type=%s", totalEvents, event.Type, part.Type))
+
+			if event.Type == "text" && part.Text != "" {
+				opencodeMessage.WriteString(part.Text)
+				notifyMessage()
+			}
+
+			if part.Type == "step-finish" && part.Reason == "stop" {
+				notifyComplete()
+			}
+			continue
+		}
+
+		// Handle Codex events
+		if isCodex {
+			var details []string
+			if event.ThreadID != "" {
+				details = append(details, fmt.Sprintf("thread_id=%s", event.ThreadID))
+			}
+
+			if len(details) > 0 {
+				infoFn(fmt.Sprintf("Parsed event #%d type=%s (%s)", totalEvents, event.Type, strings.Join(details, ", ")))
+			} else {
+				infoFn(fmt.Sprintf("Parsed event #%d type=%s", totalEvents, event.Type))
+			}
+
+			switch event.Type {
+			case "thread.started":
+				threadID = event.ThreadID
+				infoFn(fmt.Sprintf("thread.started event thread_id=%s", threadID))
+
+			case "thread.completed":
+				if event.ThreadID != "" && threadID == "" {
+					threadID = event.ThreadID
+				}
+				infoFn(fmt.Sprintf("thread.completed event thread_id=%s", event.ThreadID))
+				notifyComplete()
+
+			case "turn.completed":
+				infoFn("turn.completed event")
+				notifyComplete()
+
+			case "item.completed":
+				var itemType string
+				if len(event.Item) > 0 {
+					var itemHeader struct {
+						Type string `json:"type"`
+					}
+					if err := json.Unmarshal(event.Item, &itemHeader); err == nil {
+						itemType = itemHeader.Type
+					}
+				}
+
+				if itemType == "agent_message" && len(event.Item) > 0 {
+					// Lazy parse: only parse item content when needed
+					var item ItemContent
+					if err := json.Unmarshal(event.Item, &item); err == nil {
+						normalized := NormalizeText(item.Text)
+						infoFn(fmt.Sprintf("item.completed event item_type=%s message_len=%d", itemType, len(normalized)))
+						if normalized != "" {
+							codexMessage = normalized
+							notifyMessage()
+						}
+					} else {
+						warnFn(fmt.Sprintf("Failed to parse item content: %s", err.Error()))
+					}
+				} else {
+					infoFn(fmt.Sprintf("item.completed event item_type=%s", itemType))
+				}
+			}
+			continue
+		}
+
+		// Handle Claude events
+		if isClaude {
+			if event.SessionID != "" && threadID == "" {
+				threadID = event.SessionID
+			}
+
+			infoFn(fmt.Sprintf("Parsed Claude event #%d type=%s subtype=%s result_len=%d", totalEvents, event.Type, event.Subtype, len(event.Result)))
+
+			if event.Result != "" {
+				claudeMessage = event.Result
+				notifyMessage()
+			}
+
+			if event.Type == "result" {
+				notifyComplete()
+			}
+			continue
+		}
+
+		// Handle Gemini events
+		if isGemini {
+			if event.SessionID != "" && threadID == "" {
+				threadID = event.SessionID
+			}
+
+			if event.Content != "" {
+				geminiBuffer.WriteString(event.Content)
+			}
+
+			if event.Status != "" {
+				notifyMessage()
+
+				if event.Type == "result" && (event.Status == "success" || event.Status == "error" || event.Status == "complete" || event.Status == "failed") {
+					notifyComplete()
+				}
+			}
+
+			delta := false
+			if event.Delta != nil {
+				delta = *event.Delta
+			}
+
+			infoFn(fmt.Sprintf("Parsed Gemini event #%d type=%s role=%s delta=%t status=%s content_len=%d", totalEvents, event.Type, event.Role, delta, event.Status, len(event.Content)))
+			continue
+		}
+
+		// Unknown event format from other backends (turn.started/assistant/user); ignore.
+		continue
+	}
+
+	switch {
+	case opencodeMessage.Len() > 0:
+		message = opencodeMessage.String()
+	case geminiBuffer.Len() > 0:
+		message = geminiBuffer.String()
+	case claudeMessage != "":
+		message = claudeMessage
+	default:
+		message = codexMessage
+	}
+
+	infoFn(fmt.Sprintf("parseJSONStream completed: events=%d, message_len=%d, thread_id_found=%t", totalEvents, len(message), threadID != ""))
+	return message, threadID
+}
+
+func HasKey(m map[string]json.RawMessage, key string) bool {
+	_, ok := m[key]
+	return ok
+}
+
+func DiscardInvalidJSON(decoder *json.Decoder, reader *bufio.Reader) (*bufio.Reader, error) {
+	var buffered bytes.Buffer
+
+	if decoder != nil {
+		if buf := decoder.Buffered(); buf != nil {
+			_, _ = buffered.ReadFrom(buf)
+		}
+	}
+
+	line, err := reader.ReadBytes('\n')
+	buffered.Write(line)
+
+	data := buffered.Bytes()
+	newline := bytes.IndexByte(data, '\n')
+	if newline == -1 {
+		return reader, err
+	}
+
+	remaining := data[newline+1:]
+	if len(remaining) == 0 {
+		return reader, err
+	}
+
+	return bufio.NewReader(io.MultiReader(bytes.NewReader(remaining), reader)), err
+}
+
+func readLineWithLimit(r *bufio.Reader, maxBytes int, previewBytes int, scratch *lineScratch) (line []byte, tooLong bool, err error) {
+	if r == nil {
+		return nil, false, errors.New("reader is nil")
+	}
+	if maxBytes <= 0 {
+		return nil, false, errors.New("maxBytes must be > 0")
+	}
+	if previewBytes < 0 {
+		previewBytes = 0
+	}
+
+	part, isPrefix, err := r.ReadLine()
+	if err != nil {
+		return nil, false, err
+	}
+
+	if !isPrefix {
+		if len(part) > maxBytes {
+			return part[:min(len(part), previewBytes)], true, nil
+		}
+		return part, false, nil
+	}
+
+	if scratch == nil {
+		scratch = &lineScratch{}
+	}
+	if scratch.preview == nil {
+		scratch.preview = make([]byte, 0, min(previewBytes, len(part)))
+	}
+	if scratch.buf == nil {
+		scratch.buf = make([]byte, 0, min(maxBytes, len(part)*2))
+	}
+
+	preview := scratch.preview[:0]
+	if previewBytes > 0 {
+		preview = append(preview, part[:min(previewBytes, len(part))]...)
+	}
+
+	buf := scratch.buf[:0]
+	total := 0
+	if len(part) > maxBytes {
+		tooLong = true
+	} else {
+		buf = append(buf, part...)
+		total = len(part)
+	}
+
+	for isPrefix {
+		part, isPrefix, err = r.ReadLine()
+		if err != nil {
+			return nil, tooLong, err
+		}
+
+		if previewBytes > 0 && len(preview) < previewBytes {
+			preview = append(preview, part[:min(previewBytes-len(preview), len(part))]...)
+		}
+
+		if !tooLong {
+			if total+len(part) > maxBytes {
+				tooLong = true
+				continue
+			}
+			buf = append(buf, part...)
+			total += len(part)
+		}
+	}
+
+	if tooLong {
+		scratch.preview = preview
+		scratch.buf = buf
+		return preview, true, nil
+	}
+	scratch.preview = preview
+	scratch.buf = buf
+	return buf, false, nil
+}
+
+func TruncateBytes(b []byte, maxLen int) string {
+	if len(b) <= maxLen {
+		return string(b)
+	}
+	if maxLen < 0 {
+		return ""
+	}
+	return string(b[:maxLen]) + "..."
+}
+
+func NormalizeText(text interface{}) string {
+	switch v := text.(type) {
+	case string:
+		return v
+	case []interface{}:
+		var sb strings.Builder
+		for _, item := range v {
+			if s, ok := item.(string); ok {
+				sb.WriteString(s)
+			}
+		}
+		return sb.String()
+	default:
+		return ""
+	}
+}
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}

codeagent-wrapper/internal/parser/parser_opencode_test.go

@@ -0,0 +1,50 @@
+package parser
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestParseJSONStream_Opencode(t *testing.T) {
+	input := `{"type":"step_start","timestamp":1768187730683,"sessionID":"ses_44fced3c7ffe83sZpzY1rlQka3","part":{"id":"prt_bb0339afa001NTqoJ2NS8x91zP","sessionID":"ses_44fced3c7ffe83sZpzY1rlQka3","messageID":"msg_bb033866f0011oZxTqvfy0TKtS","type":"step-start","snapshot":"904f0fd58c125b79e60f0993e38f9d9f6200bf47"}}
+{"type":"text","timestamp":1768187744432,"sessionID":"ses_44fced3c7ffe83sZpzY1rlQka3","part":{"id":"prt_bb0339cb5001QDd0Lh0PzFZpa3","sessionID":"ses_44fced3c7ffe83sZpzY1rlQka3","messageID":"msg_bb033866f0011oZxTqvfy0TKtS","type":"text","text":"Hello from opencode"}}
+{"type":"step_finish","timestamp":1768187744471,"sessionID":"ses_44fced3c7ffe83sZpzY1rlQka3","part":{"id":"prt_bb033d0af0019VRZzpO2OVW1na","sessionID":"ses_44fced3c7ffe83sZpzY1rlQka3","messageID":"msg_bb033866f0011oZxTqvfy0TKtS","type":"step-finish","reason":"stop","snapshot":"904f0fd58c125b79e60f0993e38f9d9f6200bf47","cost":0}}`
+
+	message, threadID := ParseJSONStreamInternal(strings.NewReader(input), nil, nil, nil, nil)
+
+	if threadID != "ses_44fced3c7ffe83sZpzY1rlQka3" {
+		t.Errorf("threadID = %q, want %q", threadID, "ses_44fced3c7ffe83sZpzY1rlQka3")
+	}
+	if message != "Hello from opencode" {
+		t.Errorf("message = %q, want %q", message, "Hello from opencode")
+	}
+}
+
+func TestParseJSONStream_Opencode_MultipleTextEvents(t *testing.T) {
+	input := `{"type":"text","sessionID":"ses_123","part":{"type":"text","text":"Part 1"}}
+{"type":"text","sessionID":"ses_123","part":{"type":"text","text":" Part 2"}}
+{"type":"step_finish","sessionID":"ses_123","part":{"type":"step-finish","reason":"stop"}}`
+
+	message, threadID := ParseJSONStreamInternal(strings.NewReader(input), nil, nil, nil, nil)
+
+	if threadID != "ses_123" {
+		t.Errorf("threadID = %q, want %q", threadID, "ses_123")
+	}
+	if message != "Part 1 Part 2" {
+		t.Errorf("message = %q, want %q", message, "Part 1 Part 2")
+	}
+}
+
+func TestParseJSONStream_Opencode_NoStopReason(t *testing.T) {
+	input := `{"type":"text","sessionID":"ses_456","part":{"type":"text","text":"Content"}}
+{"type":"step_finish","sessionID":"ses_456","part":{"type":"step-finish","reason":"tool-calls"}}`
+
+	message, threadID := ParseJSONStreamInternal(strings.NewReader(input), nil, nil, nil, nil)
+
+	if threadID != "ses_456" {
+		t.Errorf("threadID = %q, want %q", threadID, "ses_456")
+	}
+	if message != "Content" {
+		t.Errorf("message = %q, want %q", message, "Content")
+	}
+}

codeagent-wrapper/internal/parser/parser_token_too_long_test.go

@@ -0,0 +1,31 @@
+package parser
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestParseJSONStream_SkipsOverlongLineAndContinues(t *testing.T) {
+	// Exceed the 10MB bufio.Scanner limit in parseJSONStreamInternal.
+	tooLong := strings.Repeat("a", 11*1024*1024)
+
+	input := strings.Join([]string{
+		`{"type":"item.completed","item":{"type":"other_type","text":"` + tooLong + `"}}`,
+		`{"type":"thread.started","thread_id":"t-1"}`,
+		`{"type":"item.completed","item":{"type":"agent_message","text":"ok"}}`,
+	}, "\n")
+
+	var warns []string
+	warnFn := func(msg string) { warns = append(warns, msg) }
+
+	gotMessage, gotThreadID := ParseJSONStreamInternal(strings.NewReader(input), warnFn, nil, nil, nil)
+	if gotMessage != "ok" {
+		t.Fatalf("message=%q, want %q (warns=%v)", gotMessage, "ok", warns)
+	}
+	if gotThreadID != "t-1" {
+		t.Fatalf("threadID=%q, want %q (warns=%v)", gotThreadID, "t-1", warns)
+	}
+	if len(warns) == 0 || !strings.Contains(warns[0], "Skipped overlong JSON line") {
+		t.Fatalf("expected warning about overlong JSON line, got %v", warns)
+	}
+}

codeagent-wrapper/internal/parser/parser_unknown_event_test.go

@@ -0,0 +1,32 @@
+package parser
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestBackendParseJSONStream_UnknownEventsAreSilent(t *testing.T) {
+	input := strings.Join([]string{
+		`{"type":"turn.started"}`,
+		`{"type":"assistant","text":"hi"}`,
+		`{"type":"user","text":"yo"}`,
+		`{"type":"item.completed","item":{"type":"agent_message","text":"ok"}}`,
+	}, "\n")
+
+	var infos []string
+	infoFn := func(msg string) { infos = append(infos, msg) }
+
+	message, threadID := ParseJSONStreamInternal(strings.NewReader(input), nil, infoFn, nil, nil)
+	if message != "ok" {
+		t.Fatalf("message=%q, want %q (infos=%v)", message, "ok", infos)
+	}
+	if threadID != "" {
+		t.Fatalf("threadID=%q, want empty (infos=%v)", threadID, infos)
+	}
+
+	for _, msg := range infos {
+		if strings.Contains(msg, "Agent event:") {
+			t.Fatalf("unexpected log for unknown event: %q", msg)
+		}
+	}
+}

codeagent-wrapper/internal/parser/truncate_bytes_test.go

@@ -0,0 +1,15 @@
+package parser
+
+import "testing"
+
+func TestTruncateBytes(t *testing.T) {
+	if got := TruncateBytes([]byte("abc"), 3); got != "abc" {
+		t.Fatalf("TruncateBytes() = %q, want %q", got, "abc")
+	}
+	if got := TruncateBytes([]byte("abcd"), 3); got != "abc..." {
+		t.Fatalf("TruncateBytes() = %q, want %q", got, "abc...")
+	}
+	if got := TruncateBytes([]byte("abcd"), -1); got != "" {
+		t.Fatalf("TruncateBytes() = %q, want empty string", got)
+	}
+}