Add daemon client protocol frames

internal/protocol/frame.go

@@ -0,0 +1,164 @@
+// Package protocol defines the daemon/client control frames shared by
+// transports. It intentionally contains data shapes only; app behavior stays
+// in internal/app until the headless daemon split is complete.
+package protocol
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+)
+
+// FrameType identifies one protocol message kind.
+type FrameType string
+
+const (
+	FrameHello          FrameType = "hello"
+	FrameAuthChallenge  FrameType = "auth_challenge"
+	FrameAuthOK         FrameType = "auth_ok"
+	FrameAttach         FrameType = "attach"
+	FrameDetach         FrameType = "detach"
+	FrameProjectList    FrameType = "project_list"
+	FrameChrome         FrameType = "chrome"
+	FramePaneSnapshot   FrameType = "pane_snapshot"
+	FramePaneChunk      FrameType = "pane_chunk"
+	FrameLifecycle      FrameType = "lifecycle"
+	FrameAttention      FrameType = "attention"
+	FrameTrustPrompt    FrameType = "trust_prompt"
+	FrameInput          FrameType = "input"
+	FrameFocus          FrameType = "focus"
+	FrameSwitchProject  FrameType = "switch_project"
+	FrameOpenProject    FrameType = "open_project"
+	FramePaletteCommand FrameType = "palette_command"
+	FrameTrustResponse  FrameType = "trust_response"
+	FrameResize         FrameType = "resize"
+)
+
+// Frame is the transport envelope. Payload is deliberately raw JSON so
+// network transports can frame without knowing every message type; loopback
+// transports may pass the same bytes without JSON re-encoding.
+type Frame struct {
+	Type      FrameType       `json:"type"`
+	RequestID string          `json:"request_id,omitempty"`
+	Payload   json.RawMessage `json:"payload,omitempty"`
+}
+
+// NewFrame marshals payload into a protocol frame.
+func NewFrame[T any](typ FrameType, payload T) (Frame, error) {
+	b, err := json.Marshal(payload)
+	if err != nil {
+		return Frame{}, fmt.Errorf("protocol: marshal %s: %w", typ, err)
+	}
+	return Frame{Type: typ, Payload: b}, nil
+}
+
+// Decode unmarshals f.Payload into v.
+func Decode[T any](f Frame) (T, error) {
+	var v T
+	if len(f.Payload) == 0 {
+		return v, nil
+	}
+	if err := json.Unmarshal(f.Payload, &v); err != nil {
+		return v, fmt.Errorf("protocol: decode %s: %w", f.Type, err)
+	}
+	return v, nil
+}
+
+type Hello struct {
+	Version    int    `json:"version"`
+	DaemonID   string `json:"daemon_id,omitempty"`
+	ClientID   string `json:"client_id,omitempty"`
+	ProjectKey string `json:"project_key,omitempty"`
+}
+
+type Attach struct {
+	Token      string `json:"token,omitempty"`
+	ProjectKey string `json:"project_key,omitempty"`
+	TermSize   Size   `json:"term_size"`
+}
+
+type Detach struct {
+	ClientID string `json:"client_id,omitempty"`
+}
+
+type Size struct {
+	Cols uint16 `json:"cols"`
+	Rows uint16 `json:"rows"`
+}
+
+type Project struct {
+	Key        string    `json:"key"`
+	Path       string    `json:"path"`
+	Name       string    `json:"name"`
+	LastActive time.Time `json:"last_active,omitempty"`
+	TabCount   int       `json:"tab_count"`
+}
+
+type ProjectList struct {
+	Projects []Project `json:"projects"`
+}
+
+type Chrome struct {
+	ProjectKey string          `json:"project_key"`
+	Model      json.RawMessage `json:"model"`
+}
+
+type PaneSnapshot struct {
+	PaneID string `json:"pane_id"`
+	Bytes  []byte `json:"bytes"`
+}
+
+type PaneChunk struct {
+	PaneID string `json:"pane_id"`
+	Bytes  []byte `json:"bytes"`
+}
+
+type LifecycleKind string
+
+const (
+	LifecycleSpawned      LifecycleKind = "spawned"
+	LifecycleExited       LifecycleKind = "exited"
+	LifecycleClosed       LifecycleKind = "closed"
+	LifecycleStateChanged LifecycleKind = "state_changed"
+)
+
+type Lifecycle struct {
+	Kind       LifecycleKind   `json:"kind"`
+	ProjectKey string          `json:"project_key,omitempty"`
+	ChildID    string          `json:"child_id,omitempty"`
+	Child      json.RawMessage `json:"child,omitempty"`
+	State      string          `json:"state,omitempty"`
+}
+
+type Input struct {
+	PaneID string `json:"pane_id"`
+	Bytes  []byte `json:"bytes"`
+}
+
+type Focus struct {
+	PaneID string `json:"pane_id,omitempty"`
+	Pad    string `json:"pad,omitempty"`
+}
+
+type SwitchProject struct {
+	Key string `json:"key"`
+}
+
+type OpenProject struct {
+	Path string `json:"path"`
+}
+
+type PaletteCommand struct {
+	Kind string          `json:"kind"`
+	Data json.RawMessage `json:"data,omitempty"`
+}
+
+type TrustResponse struct {
+	ProcessID string `json:"process_id"`
+	Preset    string `json:"preset"`
+	Allow     bool   `json:"allow"`
+}
+
+type Resize struct {
+	Size Size `json:"size"`
+}