test: add unit test for part one

internal/2015/DayFourteen/code.go

@@ -0,0 +1,63 @@
+package dayfourteen
+
+import (
+	"advent-of-code/internal/registry"
+	"os"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+func init() {
+	registry.Register("2015D14", ParseInput, PartOne, PartTwo)
+}
+
+type Reindeer struct {
+	Speed     int
+	FlyTime   int
+	RestTime  int
+	CycleTime int
+}
+
+func ParseInput(filepath string) []string {
+	content, _ := os.ReadFile(filepath)
+	return strings.Split(string(content), "\n")
+}
+
+func calculateMaxDistance(data []string, time int) int {
+	maxDistance := 0
+	pattern := regexp.MustCompile(`\w+ can fly (\d+) km/s for (\d+) seconds, but then must rest for (\d+) seconds\.`)
+
+	for _, line := range data {
+		matches := pattern.FindStringSubmatch(line)
+		var reindeer Reindeer
+		reindeer.Speed, _ = strconv.Atoi(matches[1])
+		reindeer.FlyTime, _ = strconv.Atoi(matches[2])
+		reindeer.RestTime, _ = strconv.Atoi(matches[3])
+		reindeer.CycleTime = reindeer.FlyTime + reindeer.RestTime
+
+		fullCycles := time / reindeer.CycleTime
+		distance := fullCycles * reindeer.Speed * reindeer.FlyTime
+
+		remainingTime := time % reindeer.CycleTime
+		if remainingTime > reindeer.FlyTime {
+			distance += reindeer.Speed * reindeer.FlyTime
+		} else {
+			distance += reindeer.Speed * remainingTime
+		}
+
+		if distance > maxDistance {
+			maxDistance = distance
+		}
+	}
+
+	return maxDistance
+}
+
+func PartOne(data []string) int {
+	return calculateMaxDistance(data, 2503)
+}
+
+func PartTwo(data []string) int {
+	return 0
+}

internal/2015/DayFourteen/code_test.go

@@ -0,0 +1,16 @@
+package dayfourteen
+
+import "testing"
+
+var testInput = []string{
+	"Comet can fly 14 km/s for 10 seconds, but then must rest for 127 seconds.",
+	"Dancer can fly 16 km/s for 11 seconds, but then must rest for 162 seconds.",
+}
+
+func TestPartOne(t *testing.T) {
+	expected := 1120
+	got := calculateMaxDistance(testInput, 1000)
+	if got != expected {
+		t.Errorf("calculateMaxDistance(testInput, 1000) = %d, want %d", got, expected)
+	}
+}