add countdown -> and API for phone accessing

main.go

@@ -1,3 +1,4 @@
+// main.go
 package main
 
 import (
@@ -7,7 +8,9 @@ import (
 	"log"
 	"net/http"
 	"os"
+	"path"
 	"strconv"
+	"strings"
 	"time"
 
 	_ "github.com/mattn/go-sqlite3"
@@ -19,6 +22,8 @@ var (
 	listenAddr = ":8080"
 )
 
+// --- Types ---
+
 // A single set row for display
 type SetRow struct {
 	ID        int
@@ -51,6 +56,25 @@ type Workout struct {
 	Template  string
 }
 
+// DTOs for API
+type WorkoutDTO struct {
+	ID        int       `json:"id"`
+	StartedAt time.Time `json:"started_at"`
+	EndedAt   *time.Time `json:"ended_at,omitempty"`
+	Template  string    `json:"template"`
+	SetCount  int       `json:"set_count"`
+	Volume    float64   `json:"volume"`
+}
+
+type SetDTO struct {
+	ID        int       `json:"id"`
+	WorkoutID int       `json:"workout_id"`
+	Exercise  string    `json:"exercise"`
+	Reps      int       `json:"reps"`
+	Weight    float64   `json:"weight"`
+	StartedAt time.Time `json:"started_at"`
+}
+
 func main() {
 	var err error
 
@@ -61,6 +85,13 @@ func main() {
 	}
 	log.Printf("Using database file: %s", dbPath)
 
+	// Ensure directory exists if path includes folder
+	if dir := path.Dir(dbPath); dir != "." {
+		if err := os.MkdirAll(dir, 0755); err != nil {
+			log.Fatalf("failed to create db directory %s: %v", dir, err)
+		}
+	}
+
 	// Open SQLite DB
 	db, err = sql.Open("sqlite3", dbPath)
 	if err != nil {
@@ -78,17 +109,22 @@ func main() {
 		"eq":  func(a, b interface{}) bool { return a == b },
 	}).Parse(indexHTML))
 
-	// Routes
+	// Routes (HTML)
 	http.HandleFunc("/", handleIndex)
 	http.HandleFunc("/start", handleStartWorkout)
 	http.HandleFunc("/finish", handleFinishWorkout)
 	http.HandleFunc("/add-set", handleAddSet)
 
-	// APIs
+	// Existing APIs
 	http.HandleFunc("/api/rest-times", handleRestTimes)
 	http.HandleFunc("/api/volume", handleVolumeStats)
 	http.HandleFunc("/api/last-set", handleLastSet)
 
+	// New JSON APIs for mobile app
+	http.HandleFunc("/api/workouts", handleAPIWorkouts)
+	http.HandleFunc("/api/workouts/", handleAPIWorkoutDetail) // /api/workouts/{id}
+	http.HandleFunc("/api/sets", handleAPIAddSetJSON)
+
 	log.Printf("Listening on %s ...", listenAddr)
 	if err := http.ListenAndServe(listenAddr, nil); err != nil {
 		log.Fatal(err)
@@ -124,7 +160,7 @@ CREATE TABLE IF NOT EXISTS sets (
 	return nil
 }
 
-// --- Handlers ---
+// --- HTML Handlers ---
 
 func handleIndex(w http.ResponseWriter, r *http.Request) {
 	// Current / latest workout
@@ -458,7 +494,25 @@ func handleVolumeStats(w http.ResponseWriter, r *http.Request) {
 	_ = json.NewEncoder(w).Encode(resp)
 }
 
-// --- API: last set for exercise (for autofill) ---
+func queryVolume(start, end time.Time) (float64, error) {
+	// Sum of (reps * weight) for sets whose started_at is in [start, end)
+	startStr := start.UTC().Format(time.RFC3339)
+	endStr := end.UTC().Format(time.RFC3339)
+
+	row := db.QueryRow(`
+		SELECT COALESCE(SUM(reps * weight), 0)
+		FROM sets
+		WHERE started_at >= ? AND started_at < ?
+	`, startStr, endStr)
+
+	var vol float64
+	if err := row.Scan(&vol); err != nil {
+		return 0, err
+	}
+	return vol, nil
+}
+
+// --- API: last set for exercise (autofill) ---
 
 func handleLastSet(w http.ResponseWriter, r *http.Request) {
 	ex := r.URL.Query().Get("exercise")
@@ -497,22 +551,201 @@ func handleLastSet(w http.ResponseWriter, r *http.Request) {
 	_ = json.NewEncoder(w).Encode(resp)
 }
 
-func queryVolume(start, end time.Time) (float64, error) {
+// --- JSON APIs for mobile app ---
-	// Sum of (reps * weight) for sets whose started_at is in [start, end)
-	startStr := start.UTC().Format(time.RFC3339)
-	endStr := end.UTC().Format(time.RFC3339)
 
-	row := db.QueryRow(`
+// /api/workouts
-		SELECT COALESCE(SUM(reps * weight), 0)
+// GET  -> list latest workouts
-		FROM sets
+// POST -> start new workout { "template": "A" }
-		WHERE started_at >= ? AND started_at < ?
+func handleAPIWorkouts(w http.ResponseWriter, r *http.Request) {
-	`, startStr, endStr)
+	switch r.Method {
-
+	case http.MethodGet:
-	var vol float64
+		workouts, err := getWorkoutSummaries(nil, nil)
-	if err := row.Scan(&vol); err != nil {
+		if err != nil {
-		return 0, err
+			http.Error(w, "db error", http.StatusInternalServerError)
+			return
 		}
-	return vol, nil
+		// convert to DTOs
+		var out []WorkoutDTO
+		for _, wsum := range workouts {
+			out = append(out, WorkoutDTO{
+				ID:        wsum.ID,
+				StartedAt: wsum.StartedAt,
+				EndedAt:   wsum.EndedAt,
+				Template:  wsum.Template,
+				SetCount:  wsum.SetCount,
+				Volume:    wsum.Volume,
+			})
+		}
+		w.Header().Set("Content-Type", "application/json")
+		_ = json.NewEncoder(w).Encode(out)
+	case http.MethodPost:
+		var req struct {
+			Template string `json:"template"`
+		}
+		if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+			http.Error(w, "invalid json", http.StatusBadRequest)
+			return
+		}
+		now := time.Now().UTC().Format(time.RFC3339)
+		res, err := db.Exec(`INSERT INTO workouts (started_at, template) VALUES (?, ?)`, now, req.Template)
+		if err != nil {
+			http.Error(w, "db error", http.StatusInternalServerError)
+			return
+		}
+		id64, _ := res.LastInsertId()
+		w.Header().Set("Content-Type", "application/json")
+		_ = json.NewEncoder(w).Encode(struct {
+			ID int64 `json:"id"`
+		}{ID: id64})
+	default:
+		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+	}
+}
+
+// /api/workouts/{id}
+func handleAPIWorkoutDetail(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodGet {
+		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+	// path: /api/workouts/{id}
+	parts := strings.Split(strings.Trim(r.URL.Path, "/"), "/")
+	if len(parts) != 3 {
+		http.Error(w, "not found", http.StatusNotFound)
+		return
+	}
+	idStr := parts[2]
+	id, err := strconv.Atoi(idStr)
+	if err != nil {
+		http.Error(w, "invalid id", http.StatusBadRequest)
+		return
+	}
+
+	// get workout
+	row := db.QueryRow(`SELECT id, started_at, ended_at, template FROM workouts WHERE id = ?`, id)
+	var wid int
+	var startedStr string
+	var endedStr sql.NullString
+	var templateStr sql.NullString
+	if err := row.Scan(&wid, &startedStr, &endedStr, &templateStr); err != nil {
+		if err == sql.ErrNoRows {
+			http.Error(w, "not found", http.StatusNotFound)
+			return
+		}
+		http.Error(w, "db error", http.StatusInternalServerError)
+		return
+	}
+	started, err := time.Parse(time.RFC3339, startedStr)
+	if err != nil {
+		http.Error(w, "time parse error", http.StatusInternalServerError)
+		return
+	}
+	var ended *time.Time
+	if endedStr.Valid && endedStr.String != "" {
+		t, err := time.Parse(time.RFC3339, endedStr.String)
+		if err == nil {
+			ended = &t
+		}
+	}
+	tmpl := ""
+	if templateStr.Valid {
+		tmpl = templateStr.String
+	}
+
+	// sets
+	setsRows, err := getSetsForWorkout(id)
+	if err != nil {
+		http.Error(w, "db error", http.StatusInternalServerError)
+		return
+	}
+	var sets []SetDTO
+	for _, s := range setsRows {
+		sets = append(sets, SetDTO{
+			ID:        s.ID,
+			WorkoutID: id,
+			Exercise:  s.Exercise,
+			Reps:      s.Reps,
+			Weight:    s.Weight,
+			StartedAt: s.StartedAt,
+		})
+	}
+
+	// volume
+	var volume float64
+	for _, s := range setsRows {
+		volume += float64(s.Reps) * s.Weight
+	}
+
+	resp := struct {
+		Workout WorkoutDTO `json:"workout"`
+		Sets    []SetDTO   `json:"sets"`
+	}{
+		Workout: WorkoutDTO{
+			ID:        wid,
+			StartedAt: started,
+			EndedAt:   ended,
+			Template:  tmpl,
+			SetCount:  len(setsRows),
+			Volume:    volume,
+		},
+		Sets: sets,
+	}
+
+	w.Header().Set("Content-Type", "application/json")
+	_ = json.NewEncoder(w).Encode(resp)
+}
+
+// /api/sets (POST JSON) -> create set
+func handleAPIAddSetJSON(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+	var req struct {
+		WorkoutID int     `json:"workout_id"`
+		Exercise  string  `json:"exercise"`
+		Reps      int     `json:"reps"`
+		Weight    float64 `json:"weight"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		http.Error(w, "invalid json", http.StatusBadRequest)
+		return
+	}
+
+	// choose workout id: if 0 -> latest
+	var workoutID int
+	if req.WorkoutID == 0 {
+		latest, err := getLatestWorkout()
+		if err != nil || latest == nil {
+			http.Error(w, "no active workout", http.StatusBadRequest)
+			return
+		}
+		workoutID = latest.ID
+	} else {
+		workoutID = req.WorkoutID
+	}
+
+	if req.Exercise == "" || req.Reps <= 0 || req.Weight < 0 {
+		http.Error(w, "invalid payload", http.StatusBadRequest)
+		return
+	}
+
+	now := time.Now().UTC().Format(time.RFC3339)
+	res, err := db.Exec(
+		`INSERT INTO sets (workout_id, exercise, reps, weight, started_at)
+		 VALUES (?, ?, ?, ?, ?)`,
+		workoutID, req.Exercise, req.Reps, req.Weight, now,
+	)
+	if err != nil {
+		http.Error(w, "db error", http.StatusInternalServerError)
+		return
+	}
+	id64, _ := res.LastInsertId()
+
+	w.Header().Set("Content-Type", "application/json")
+	_ = json.NewEncoder(w).Encode(struct {
+		ID int64 `json:"id"`
+	}{ID: id64})
 }
 
 // --- Helpers & summaries ---
@@ -720,7 +953,7 @@ func formatDuration(d time.Duration) string {
 	return strconv.Itoa(s) + "s"
 }
 
-// --- HTML template (single page) ---
+// --- HTML template (includes rest timer card) ---
 
 const indexHTML = `
 <!DOCTYPE html>
@@ -831,11 +1064,16 @@ const indexHTML = `
 		.tag:hover {
 			background:#374151;
 		}
+		.timer-display {
+			font-size: 1.5rem;
+			font-weight: 600;
+			margin-top: 0.5rem;
+		}
 	</style>
 </head>
 <body>
 	<h1>Minimal Fitness Tracker</h1>
-	<p style="color:#9ca3af;">Self-hosted 5×5 log – A/B templates, volume, rest, and history.</p>
+	<p style="color:#9ca3af;">Self-hosted 5×5 log – A/B templates, volume, rest, history & basic API.</p>
 
 	<div class="row">
 		<div>
@@ -932,7 +1170,7 @@ const indexHTML = `
 							<input type="number" id="weightInput" name="weight" step="0.5" min="0" required>
 						</label>
 						<button type="submit">Save set (end set)</button>
-						<p class="small">Tip: the time you press “Save set” is used as the set time. Rest between sets is calculated automatically.</p>
+						<p class="small">Time you press “Save set” = set timestamp. Rest between sets is automatic.</p>
 					</form>
 				{{else}}
 					<p style="color:#fbbf24;">Start a workout first.</p>
@@ -988,6 +1226,17 @@ const indexHTML = `
 				<canvas id="volumeChart" height="120" style="margin-top:0.5rem;"></canvas>
 				<p id="volumeInfo" style="font-size:0.85rem; color:#9ca3af; margin-top:0.3rem;"></p>
 			</div>
+
+			<div class="card">
+				<h2>Rest timer (with notification)</h2>
+				<label>
+					Rest seconds
+					<input type="number" id="restSeconds" min="10" step="5" value="90">
+				</label>
+				<button type="button" onclick="startRestTimer()">Start rest</button>
+				<div id="restCountdown" class="timer-display"></div>
+				<p class="small">When the timer ends, you’ll get a browser notification (if allowed).</p>
+			</div>
 		</div>
 	</div>
 
@@ -1053,6 +1302,8 @@ const indexHTML = `
 	<script>
 		let restChartInstance = null;
 		let volumeChartInstance = null;
+		let restTimerInterval = null;
+		let restTimerEnd = null;
 
 		function toggleCustomExercise() {
 			const select = document.getElementById('exercise_select');
@@ -1220,6 +1471,55 @@ const indexHTML = `
 				});
 		}
 
+		// --- Rest timer with notification ---
+
+		function startRestTimer() {
+			const input = document.getElementById('restSeconds');
+			const display = document.getElementById('restCountdown');
+			let sec = parseInt(input.value, 10);
+			if (isNaN(sec) || sec <= 0) {
+				sec = 90;
+				input.value = 90;
+			}
+
+			// Ask for notification permission once
+			if ('Notification' in window && Notification.permission === 'default') {
+				Notification.requestPermission();
+			}
+
+			restTimerEnd = Date.now() + sec * 1000;
+			updateRestCountdown(); // immediate
+
+			if (restTimerInterval) {
+				clearInterval(restTimerInterval);
+			}
+			restTimerInterval = setInterval(updateRestCountdown, 250);
+		}
+
+		function updateRestCountdown() {
+			const display = document.getElementById('restCountdown');
+			if (!restTimerEnd) {
+				display.textContent = '';
+				return;
+			}
+			const now = Date.now();
+			const remainingMs = restTimerEnd - now;
+			if (remainingMs <= 0) {
+				display.textContent = "0s";
+				clearInterval(restTimerInterval);
+				restTimerInterval = null;
+				restTimerEnd = null;
+
+				// Fire notification if allowed
+				if ('Notification' in window && Notification.permission === 'granted') {
+					new Notification("Rest done – time to lift! 💪");
+				}
+				return;
+			}
+			const sec = Math.round(remainingMs / 1000);
+			display.textContent = sec + "s";
+		}
+
 		document.addEventListener('DOMContentLoaded', () => {
 			toggleCustomExercise();
 			onExerciseChange();