Refactor: Add cache key constants and configurable template path

Code quality improvements:
- Define CacheKey* constants in store package for type safety
- Add TemplateDir to config (default: web/templates, env: TEMPLATE_DIR)
- Update handlers to use store.CacheKey* instead of hardcoded strings
- Update NewTabsHandler to accept templateDir parameter
- Use filepath.Join for cross-platform template path construction

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

6 files changed, 27 insertions, 15 deletions

diff --git a/cmd/dashboard/main.go b/cmd/dashboard/main.go
index 30b90ab..e52aeb0 100644
--- a/cmd/dashboard/main.go
+++ b/cmd/dashboard/main.go
@@ -52,7 +52,7 @@ func main() {
 
 	// Initialize handlers
 	h := handlers.New(db, todoistClient, trelloClient, obsidianClient, planToEatClient, cfg)
-	tabsHandler := handlers.NewTabsHandler(db)
+	tabsHandler := handlers.NewTabsHandler(db, cfg.TemplateDir)
 
 	// Set up router
 	r := chi.NewRouter()
diff --git a/internal/config/config.go b/internal/config/config.go
index dc7d1c3..93f57cc 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -17,6 +17,7 @@ type Config struct {
 	// Paths
 	ObsidianVaultPath string
 	DatabasePath      string
+	TemplateDir       string
 
 	// Server
 	Port            string
@@ -36,6 +37,7 @@ func Load() (*Config, error) {
 		// Paths
 		ObsidianVaultPath: os.Getenv("OBSIDIAN_VAULT_PATH"),
 		DatabasePath:      getEnvWithDefault("DATABASE_PATH", "./dashboard.db"),
+		TemplateDir:       getEnvWithDefault("TEMPLATE_DIR", "web/templates"),
 
 		// Server
 		Port:            getEnvWithDefault("PORT", "8080"),
diff --git a/internal/handlers/handlers.go b/internal/handlers/handlers.go
index 20095fe..0af2bba 100644
--- a/internal/handlers/handlers.go
+++ b/internal/handlers/handlers.go
@@ -7,6 +7,7 @@ import (
 	"html/template"
 	"log"
 	"net/http"
+	"path/filepath"
 	"sort"
 	"strings"
 	"sync"
@@ -30,21 +31,21 @@ type Handler struct {
 }
 
 // New creates a new Handler instance
-func New(store *store.Store, todoist api.TodoistAPI, trello api.TrelloAPI, obsidian api.ObsidianAPI, planToEat api.PlanToEatAPI, cfg *config.Config) *Handler {
+func New(s *store.Store, todoist api.TodoistAPI, trello api.TrelloAPI, obsidian api.ObsidianAPI, planToEat api.PlanToEatAPI, cfg *config.Config) *Handler {
 	// Parse templates including partials
-	tmpl, err := template.ParseGlob("web/templates/*.html")
+	tmpl, err := template.ParseGlob(filepath.Join(cfg.TemplateDir, "*.html"))
 	if err != nil {
 		log.Printf("Warning: failed to parse templates: %v", err)
 	}
 
 	// Also parse partials
-	tmpl, err = tmpl.ParseGlob("web/templates/partials/*.html")
+	tmpl, err = tmpl.ParseGlob(filepath.Join(cfg.TemplateDir, "partials", "*.html"))
 	if err != nil {
 		log.Printf("Warning: failed to parse partial templates: %v", err)
 	}
 
 	return &Handler{
-		store:           store,
+		store:           s,
 		todoistClient:   todoist,
 		trelloClient:    trello,
 		obsidianClient:  obsidian,
@@ -351,7 +352,7 @@ func (h *Handler) aggregateData(ctx context.Context, forceRefresh bool) (*models
 
 // fetchTasks fetches tasks from cache or API
 func (h *Handler) fetchTasks(ctx context.Context, forceRefresh bool) ([]models.Task, error) {
-	cacheKey := "todoist_tasks"
+	cacheKey := store.CacheKeyTodoistTasks
 
 	// Check cache validity
 	if !forceRefresh {
@@ -387,7 +388,7 @@ func (h *Handler) fetchTasks(ctx context.Context, forceRefresh bool) ([]models.T
 
 // fetchNotes fetches notes from cache or filesystem
 func (h *Handler) fetchNotes(ctx context.Context, forceRefresh bool) ([]models.Note, error) {
-	cacheKey := "obsidian_notes"
+	cacheKey := store.CacheKeyObsidianNotes
 
 	// Check cache validity
 	if !forceRefresh {
@@ -423,7 +424,7 @@ func (h *Handler) fetchNotes(ctx context.Context, forceRefresh bool) ([]models.N
 
 // fetchMeals fetches meals from cache or API
 func (h *Handler) fetchMeals(ctx context.Context, forceRefresh bool) ([]models.Meal, error) {
-	cacheKey := "plantoeat_meals"
+	cacheKey := store.CacheKeyPlanToEatMeals
 
 	// Check cache validity
 	if !forceRefresh {
@@ -463,7 +464,7 @@ func (h *Handler) fetchMeals(ctx context.Context, forceRefresh bool) ([]models.M
 
 // fetchBoards fetches Trello boards from cache or API
 func (h *Handler) fetchBoards(ctx context.Context, forceRefresh bool) ([]models.Board, error) {
-	cacheKey := "trello_boards"
+	cacheKey := store.CacheKeyTrelloBoards
 
 	// Check cache validity
 	if !forceRefresh {
@@ -765,7 +766,7 @@ func (h *Handler) HandleUnifiedAdd(w http.ResponseWriter, r *http.Request) {
 			return
 		}
 		// Invalidate cache so fresh data is fetched
-		h.store.InvalidateCache("todoist_tasks")
+		h.store.InvalidateCache(store.CacheKeyTodoistTasks)
 
 	case "trello":
 		listID := r.FormValue("list_id")
@@ -780,7 +781,7 @@ func (h *Handler) HandleUnifiedAdd(w http.ResponseWriter, r *http.Request) {
 			return
 		}
 		// Invalidate cache so fresh data is fetched
-		h.store.InvalidateCache("trello_boards")
+		h.store.InvalidateCache(store.CacheKeyTrelloBoards)
 
 	default:
 		http.Error(w, "Invalid source", http.StatusBadRequest)
diff --git a/internal/handlers/heuristic_test.go b/internal/handlers/heuristic_test.go
index f76fdc0..dc8620a 100644
--- a/internal/handlers/heuristic_test.go
+++ b/internal/handlers/heuristic_test.go
@@ -63,7 +63,7 @@ func TestHandleTasks_Heuristic(t *testing.T) {
 	}
 
 	// Create Handler
-	h := NewTabsHandler(db)
+	h := NewTabsHandler(db, "../../web/templates")
 
 	// Skip if templates are not loaded
 	if h.templates == nil {
diff --git a/internal/handlers/tabs.go b/internal/handlers/tabs.go
index 74dfbe8..ffdabb0 100644
--- a/internal/handlers/tabs.go
+++ b/internal/handlers/tabs.go
@@ -4,6 +4,7 @@ import (
 	"html/template"
 	"log"
 	"net/http"
+	"path/filepath"
 	"sort"
 	"strings"
 	"time"
@@ -31,15 +32,15 @@ type TabsHandler struct {
 }
 
 // NewTabsHandler creates a new TabsHandler instance
-func NewTabsHandler(store *store.Store) *TabsHandler {
+func NewTabsHandler(store *store.Store, templateDir string) *TabsHandler {
 	// Parse templates including partials
-	tmpl, err := template.ParseGlob("web/templates/*.html")
+	tmpl, err := template.ParseGlob(filepath.Join(templateDir, "*.html"))
 	if err != nil {
 		log.Printf("Warning: failed to parse templates: %v", err)
 	}
 
 	// Also parse partials
-	tmpl, err = tmpl.ParseGlob("web/templates/partials/*.html")
+	tmpl, err = tmpl.ParseGlob(filepath.Join(templateDir, "partials", "*.html"))
 	if err != nil {
 		log.Printf("Warning: failed to parse partial templates: %v", err)
 	}
diff --git a/internal/store/sqlite.go b/internal/store/sqlite.go
index 259bd0f..5f58fd4 100644
--- a/internal/store/sqlite.go
+++ b/internal/store/sqlite.go
@@ -13,6 +13,14 @@ import (
 	"task-dashboard/internal/models"
 )
 
+// Cache key constants
+const (
+	CacheKeyTodoistTasks  = "todoist_tasks"
+	CacheKeyTrelloBoards  = "trello_boards"
+	CacheKeyObsidianNotes = "obsidian_notes"
+	CacheKeyPlanToEatMeals = "plantoeat_meals"
+)
+
 type Store struct {
 	db *sql.DB
 }