feat: add config package with types and JSON serialization

Types: - TownConfig: main town configuration (config/town.json) - RigsConfig: rigs registry with BeadsConfig per rig - AgentState: agent state with role, session, extras Features: - Load/Save functions for all types - Version compatibility checks - Required field validation - Creates parent directories on save Closes gt-f9x.1 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
2025-12-16 13:24:28 -08:00
parent a4677191d1
commit e16931b304
3 changed files with 365 additions and 0 deletions
--- a/internal/config/loader.go
+++ b/internal/config/loader.go
@@ -0,0 +1,188 @@
+package config
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+var (
+	// ErrNotFound indicates the config file does not exist.
+	ErrNotFound = errors.New("config file not found")
+
+	// ErrInvalidVersion indicates an unsupported schema version.
+	ErrInvalidVersion = errors.New("unsupported config version")
+
+	// ErrInvalidType indicates an unexpected config type.
+	ErrInvalidType = errors.New("invalid config type")
+
+	// ErrMissingField indicates a required field is missing.
+	ErrMissingField = errors.New("missing required field")
+)
+
+// LoadTownConfig loads and validates a town configuration file.
+func LoadTownConfig(path string) (*TownConfig, error) {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, fmt.Errorf("%w: %s", ErrNotFound, path)
+		}
+		return nil, fmt.Errorf("reading config: %w", err)
+	}
+
+	var config TownConfig
+	if err := json.Unmarshal(data, &config); err != nil {
+		return nil, fmt.Errorf("parsing config: %w", err)
+	}
+
+	if err := validateTownConfig(&config); err != nil {
+		return nil, err
+	}
+
+	return &config, nil
+}
+
+// SaveTownConfig saves a town configuration to a file.
+func SaveTownConfig(path string, config *TownConfig) error {
+	if err := validateTownConfig(config); err != nil {
+		return err
+	}
+
+	if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil {
+		return fmt.Errorf("creating directory: %w", err)
+	}
+
+	data, err := json.MarshalIndent(config, "", "  ")
+	if err != nil {
+		return fmt.Errorf("encoding config: %w", err)
+	}
+
+	if err := os.WriteFile(path, data, 0644); err != nil {
+		return fmt.Errorf("writing config: %w", err)
+	}
+
+	return nil
+}
+
+// LoadRigsConfig loads and validates a rigs registry file.
+func LoadRigsConfig(path string) (*RigsConfig, error) {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, fmt.Errorf("%w: %s", ErrNotFound, path)
+		}
+		return nil, fmt.Errorf("reading config: %w", err)
+	}
+
+	var config RigsConfig
+	if err := json.Unmarshal(data, &config); err != nil {
+		return nil, fmt.Errorf("parsing config: %w", err)
+	}
+
+	if err := validateRigsConfig(&config); err != nil {
+		return nil, err
+	}
+
+	return &config, nil
+}
+
+// SaveRigsConfig saves a rigs registry to a file.
+func SaveRigsConfig(path string, config *RigsConfig) error {
+	if err := validateRigsConfig(config); err != nil {
+		return err
+	}
+
+	if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil {
+		return fmt.Errorf("creating directory: %w", err)
+	}
+
+	data, err := json.MarshalIndent(config, "", "  ")
+	if err != nil {
+		return fmt.Errorf("encoding config: %w", err)
+	}
+
+	if err := os.WriteFile(path, data, 0644); err != nil {
+		return fmt.Errorf("writing config: %w", err)
+	}
+
+	return nil
+}
+
+// LoadAgentState loads an agent state file.
+func LoadAgentState(path string) (*AgentState, error) {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, fmt.Errorf("%w: %s", ErrNotFound, path)
+		}
+		return nil, fmt.Errorf("reading state: %w", err)
+	}
+
+	var state AgentState
+	if err := json.Unmarshal(data, &state); err != nil {
+		return nil, fmt.Errorf("parsing state: %w", err)
+	}
+
+	if err := validateAgentState(&state); err != nil {
+		return nil, err
+	}
+
+	return &state, nil
+}
+
+// SaveAgentState saves an agent state to a file.
+func SaveAgentState(path string, state *AgentState) error {
+	if err := validateAgentState(state); err != nil {
+		return err
+	}
+
+	if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil {
+		return fmt.Errorf("creating directory: %w", err)
+	}
+
+	data, err := json.MarshalIndent(state, "", "  ")
+	if err != nil {
+		return fmt.Errorf("encoding state: %w", err)
+	}
+
+	if err := os.WriteFile(path, data, 0644); err != nil {
+		return fmt.Errorf("writing state: %w", err)
+	}
+
+	return nil
+}
+
+// validateTownConfig validates a TownConfig.
+func validateTownConfig(c *TownConfig) error {
+	if c.Type != "town" && c.Type != "" {
+		return fmt.Errorf("%w: expected type 'town', got '%s'", ErrInvalidType, c.Type)
+	}
+	if c.Version > CurrentTownVersion {
+		return fmt.Errorf("%w: got %d, max supported %d", ErrInvalidVersion, c.Version, CurrentTownVersion)
+	}
+	if c.Name == "" {
+		return fmt.Errorf("%w: name", ErrMissingField)
+	}
+	return nil
+}
+
+// validateRigsConfig validates a RigsConfig.
+func validateRigsConfig(c *RigsConfig) error {
+	if c.Version > CurrentRigsVersion {
+		return fmt.Errorf("%w: got %d, max supported %d", ErrInvalidVersion, c.Version, CurrentRigsVersion)
+	}
+	if c.Rigs == nil {
+		c.Rigs = make(map[string]RigEntry)
+	}
+	return nil
+}
+
+// validateAgentState validates an AgentState.
+func validateAgentState(s *AgentState) error {
+	if s.Role == "" {
+		return fmt.Errorf("%w: role", ErrMissingField)
+	}
+	return nil
+}
--- a/internal/config/loader_test.go
+++ b/internal/config/loader_test.go
@@ -0,0 +1,132 @@
+package config
+
+import (
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+func TestTownConfigRoundTrip(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config", "town.json")
+
+	original := &TownConfig{
+		Type:      "town",
+		Version:   1,
+		Name:      "test-town",
+		CreatedAt: time.Now().Truncate(time.Second),
+	}
+
+	if err := SaveTownConfig(path, original); err != nil {
+		t.Fatalf("SaveTownConfig: %v", err)
+	}
+
+	loaded, err := LoadTownConfig(path)
+	if err != nil {
+		t.Fatalf("LoadTownConfig: %v", err)
+	}
+
+	if loaded.Name != original.Name {
+		t.Errorf("Name = %q, want %q", loaded.Name, original.Name)
+	}
+	if loaded.Type != original.Type {
+		t.Errorf("Type = %q, want %q", loaded.Type, original.Type)
+	}
+}
+
+func TestRigsConfigRoundTrip(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config", "rigs.json")
+
+	original := &RigsConfig{
+		Version: 1,
+		Rigs: map[string]RigEntry{
+			"gastown": {
+				GitURL:  "git@github.com:steveyegge/gastown.git",
+				AddedAt: time.Now().Truncate(time.Second),
+				BeadsConfig: &BeadsConfig{
+					Repo:   "local",
+					Prefix: "gt-",
+				},
+			},
+		},
+	}
+
+	if err := SaveRigsConfig(path, original); err != nil {
+		t.Fatalf("SaveRigsConfig: %v", err)
+	}
+
+	loaded, err := LoadRigsConfig(path)
+	if err != nil {
+		t.Fatalf("LoadRigsConfig: %v", err)
+	}
+
+	if len(loaded.Rigs) != 1 {
+		t.Errorf("Rigs count = %d, want 1", len(loaded.Rigs))
+	}
+
+	rig, ok := loaded.Rigs["gastown"]
+	if !ok {
+		t.Fatal("missing 'gastown' rig")
+	}
+	if rig.BeadsConfig == nil || rig.BeadsConfig.Prefix != "gt-" {
+		t.Errorf("BeadsConfig.Prefix = %v, want 'gt-'", rig.BeadsConfig)
+	}
+}
+
+func TestAgentStateRoundTrip(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "state.json")
+
+	original := &AgentState{
+		Role:       "mayor",
+		LastActive: time.Now().Truncate(time.Second),
+		Session:    "abc123",
+		Extra: map[string]any{
+			"custom": "value",
+		},
+	}
+
+	if err := SaveAgentState(path, original); err != nil {
+		t.Fatalf("SaveAgentState: %v", err)
+	}
+
+	loaded, err := LoadAgentState(path)
+	if err != nil {
+		t.Fatalf("LoadAgentState: %v", err)
+	}
+
+	if loaded.Role != original.Role {
+		t.Errorf("Role = %q, want %q", loaded.Role, original.Role)
+	}
+	if loaded.Session != original.Session {
+		t.Errorf("Session = %q, want %q", loaded.Session, original.Session)
+	}
+}
+
+func TestLoadTownConfigNotFound(t *testing.T) {
+	_, err := LoadTownConfig("/nonexistent/path.json")
+	if err == nil {
+		t.Fatal("expected error for nonexistent file")
+	}
+}
+
+func TestValidationErrors(t *testing.T) {
+	// Missing name
+	tc := &TownConfig{Type: "town", Version: 1}
+	if err := validateTownConfig(tc); err == nil {
+		t.Error("expected error for missing name")
+	}
+
+	// Wrong type
+	tc = &TownConfig{Type: "wrong", Version: 1, Name: "test"}
+	if err := validateTownConfig(tc); err == nil {
+		t.Error("expected error for wrong type")
+	}
+
+	// Missing role
+	as := &AgentState{}
+	if err := validateAgentState(as); err == nil {
+		t.Error("expected error for missing role")
+	}
+}
--- a/internal/config/types.go
+++ b/internal/config/types.go
@@ -0,0 +1,45 @@
+// Package config provides configuration types and serialization for Gas Town.
+package config
+
+import "time"
+
+// TownConfig represents the main town configuration (config/town.json).
+type TownConfig struct {
+	Type      string    `json:"type"`       // "town"
+	Version   int       `json:"version"`    // schema version
+	Name      string    `json:"name"`       // town identifier
+	CreatedAt time.Time `json:"created_at"`
+}
+
+// RigsConfig represents the rigs registry (config/rigs.json).
+type RigsConfig struct {
+	Version int                 `json:"version"`
+	Rigs    map[string]RigEntry `json:"rigs"`
+}
+
+// RigEntry represents a single rig in the registry.
+type RigEntry struct {
+	GitURL      string       `json:"git_url"`
+	AddedAt     time.Time    `json:"added_at"`
+	BeadsConfig *BeadsConfig `json:"beads,omitempty"`
+}
+
+// BeadsConfig represents beads configuration for a rig.
+type BeadsConfig struct {
+	Repo   string `json:"repo"`   // "local" | path | git-url
+	Prefix string `json:"prefix"` // issue prefix
+}
+
+// AgentState represents an agent's current state (*/state.json).
+type AgentState struct {
+	Role       string         `json:"role"`              // "mayor", "witness", etc.
+	LastActive time.Time      `json:"last_active"`
+	Session    string         `json:"session,omitempty"`
+	Extra      map[string]any `json:"extra,omitempty"`
+}
+
+// CurrentTownVersion is the current schema version for TownConfig.
+const CurrentTownVersion = 1
+
+// CurrentRigsVersion is the current schema version for RigsConfig.
+const CurrentRigsVersion = 1