feat: add local skill store and targets

internal/targets/targets.go

@@ -0,0 +1,117 @@
+package targets
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"sgg-ai-skill-manager/internal/domain"
+)
+
+type Target struct {
+	ID        string
+	Name      string
+	SkillsDir string
+}
+
+type Manager struct {
+	Targets map[string]Target
+}
+
+func New(targets map[string]Target) *Manager {
+	return &Manager{Targets: targets}
+}
+
+func DefaultTargets(home string) map[string]Target {
+	return map[string]Target{
+		"codex": {
+			ID:        "codex",
+			Name:      "Codex",
+			SkillsDir: filepath.Join(home, ".codex", "skills"),
+		},
+		"claude": {
+			ID:        "claude",
+			Name:      "Claude",
+			SkillsDir: filepath.Join(home, ".claude", "skills"),
+		},
+	}
+}
+
+func (m *Manager) Install(skill domain.SkillState, targetID string) (domain.SkillState, error) {
+	target, ok := m.Targets[targetID]
+	if !ok {
+		return skill, fmt.Errorf("unknown target %s", targetID)
+	}
+	if _, err := os.Stat(skill.LocalPath); err != nil {
+		return skill, fmt.Errorf("local skill path is not accessible: %w", err)
+	}
+	if skill.InstalledTargets == nil {
+		skill.InstalledTargets = map[string]domain.InstalledTarget{}
+	}
+	if err := os.MkdirAll(target.SkillsDir, 0o755); err != nil {
+		return skill, err
+	}
+	linkPath := filepath.Join(target.SkillsDir, skill.Repo)
+	if _, err := os.Lstat(linkPath); err == nil {
+		actual, readErr := ReadJunctionTarget(linkPath)
+		if readErr == nil && samePath(actual, skill.LocalPath) {
+			skill.InstalledTargets[targetID] = installedTarget(linkPath, skill.LocalPath)
+			return skill, nil
+		}
+		return skill, fmt.Errorf("target path conflict: %s", linkPath)
+	} else if !errors.Is(err, os.ErrNotExist) {
+		return skill, err
+	}
+	if err := CreateJunction(linkPath, skill.LocalPath); err != nil {
+		return skill, err
+	}
+	skill.InstalledTargets[targetID] = installedTarget(linkPath, skill.LocalPath)
+	return skill, nil
+}
+
+func (m *Manager) Uninstall(skill domain.SkillState, targetID string) (domain.SkillState, error) {
+	record, ok := skill.InstalledTargets[targetID]
+	if !ok {
+		return skill, nil
+	}
+	actual, err := ReadJunctionTarget(record.Path)
+	if err != nil {
+		return skill, fmt.Errorf("cannot verify junction target: %w", err)
+	}
+	if !samePath(actual, record.TargetPath) || !samePath(actual, skill.LocalPath) {
+		return skill, fmt.Errorf("junction target mismatch: %s", record.Path)
+	}
+	if err := RemoveJunction(record.Path); err != nil {
+		return skill, err
+	}
+	delete(skill.InstalledTargets, targetID)
+	return skill, nil
+}
+
+func (m *Manager) Status(skill domain.SkillState, targetID string) string {
+	target, ok := m.Targets[targetID]
+	if !ok {
+		return "unknown"
+	}
+	linkPath := filepath.Join(target.SkillsDir, skill.Repo)
+	actual, err := ReadJunctionTarget(linkPath)
+	if errors.Is(err, os.ErrNotExist) {
+		return "not_installed"
+	}
+	if err != nil {
+		return "conflict"
+	}
+	if samePath(actual, skill.LocalPath) {
+		return "installed"
+	}
+	return "conflict"
+}
+
+func installedTarget(linkPath, targetPath string) domain.InstalledTarget {
+	return domain.InstalledTarget{
+		Path:       linkPath,
+		LinkType:   "junction",
+		TargetPath: targetPath,
+	}
+}