checkpoint 2

internal/parser/parser.go

@@ -0,0 +1,65 @@
+package parser
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/tormoder/fit"
+	"github.com/sstent/garminsync-go/internal/models"
+)
+
+// Parser handles FIT file parsing
+type Parser struct{}
+
+func NewParser() *Parser {
+	return &Parser{}
+}
+
+func (p *Parser) ParseFile(filename string) (*models.ActivityMetrics, error) {
+	file, err := os.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	data, err := os.ReadFile(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	return p.ParseData(data)
+}
+
+func (p *Parser) ParseData(data []byte) (*models.ActivityMetrics, error) {
+	fitFile, err := fit.Decode(bytes.NewReader(data))
+	if err != nil {
+		return nil, fmt.Errorf("failed to decode FIT file: %w", err)
+	}
+
+	activity, err := fitFile.Activity()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get activity from FIT: %w", err)
+	}
+
+	if len(activity.Sessions) == 0 {
+		return nil, fmt.Errorf("no sessions found in FIT file")
+	}
+
+	session := activity.Sessions[0]
+	metrics := &models.ActivityMetrics{
+		StartTime:     session.StartTime,
+		Duration:      time.Duration(session.TotalTimerTime) * time.Second,
+		Distance:      float64(session.TotalDistance),
+		AvgHeartRate:  int(session.AvgHeartRate),
+		MaxHeartRate:  int(session.MaxHeartRate),
+		AvgPower:      int(session.AvgPower),
+		Calories:      int(session.TotalCalories),
+		ElevationGain: float64(session.TotalAscent),
+		ElevationLoss: float64(session.TotalDescent),
+		Steps:         0, // FIT sessions don't include steps
+	}
+
+	return metrics, nil
+}