refactor: massive refactor to have only one binary to call

internal/2020/DayFour/code.go

@@ -0,0 +1,154 @@
+package dayfour
+
+import (
+	"advent-of-code/internal/registry"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func init() {
+	registry.Register("2020D4", ParseInput, PartOne, PartTwo)
+}
+
+func ParseInput(filepath string) []string {
+	content, _ := os.ReadFile(filepath)
+
+	text := string(content)
+	passports := strings.Split(text, "\n\n")
+
+	result := make([]string, 0, len(passports))
+	for _, passport := range passports {
+		passport = strings.TrimSpace(passport)
+		if passport == "" {
+			continue
+		}
+		passport = strings.ReplaceAll(passport, "\n", " ")
+		passport = strings.Join(strings.Fields(passport), " ")
+		result = append(result, passport)
+	}
+	return result
+}
+
+func PartOne(data []string) int {
+	count := 0
+	required := []string{"byr", "iyr", "eyr", "hgt", "hcl", "ecl", "pid"}
+	for _, passport := range data {
+		fields := strings.Fields(passport)
+		present := make(map[string]bool)
+		for _, field := range fields {
+			if idx := strings.Index(field, ":"); idx != -1 {
+				present[field[:idx]] = true
+			}
+		}
+		missing := false
+		for _, field := range required {
+			if !present[field] {
+				missing = true
+				break
+			}
+		}
+		if !missing {
+			count++
+		}
+	}
+	return count
+}
+
+func PartTwo(data []string) int {
+	isNumberInRange := func(value string, min, max int, digits int) bool {
+		if len(value) != digits {
+			return false
+		}
+		n, err := strconv.Atoi(value)
+		if err != nil {
+			return false
+		}
+		return n >= min && n <= max
+	}
+
+	isValidHeight := func(value string) bool {
+		if len(value) < 3 {
+			return false
+		}
+		unit := value[len(value)-2:]
+		number := value[:len(value)-2]
+		n, err := strconv.Atoi(number)
+		if err != nil {
+			return false
+		}
+		if unit == "cm" {
+			return n >= 150 && n <= 193
+		}
+		if unit == "in" {
+			return n >= 59 && n <= 76
+		}
+		return false
+	}
+
+	isValidHairColor := func(value string) bool {
+		if len(value) != 7 || value[0] != '#' {
+			return false
+		}
+		for _, c := range value[1:] {
+			if !((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f')) {
+				return false
+			}
+		}
+		return true
+	}
+
+	isValidPID := func(value string) bool {
+		if len(value) != 9 {
+			return false
+		}
+		for _, c := range value {
+			if c < '0' || c > '9' {
+				return false
+			}
+		}
+		return true
+	}
+
+	validECL := map[string]bool{
+		"amb": true, "blu": true, "brn": true, "gry": true,
+		"grn": true, "hzl": true, "oth": true,
+	}
+
+	required := []string{"byr", "iyr", "eyr", "hgt", "hcl", "ecl", "pid"}
+	count := 0
+
+	for _, passport := range data {
+		fields := map[string]string{}
+		for field := range strings.FieldsSeq(passport) {
+			parts := strings.SplitN(field, ":", 2)
+			if len(parts) == 2 {
+				fields[parts[0]] = parts[1]
+			}
+		}
+
+		passportValidators := map[string]func(string) bool{
+			"byr": func(v string) bool { return isNumberInRange(v, 1920, 2002, 4) },
+			"iyr": func(v string) bool { return isNumberInRange(v, 2010, 2020, 4) },
+			"eyr": func(v string) bool { return isNumberInRange(v, 2020, 2030, 4) },
+			"hgt": isValidHeight,
+			"hcl": isValidHairColor,
+			"ecl": func(v string) bool { return validECL[v] },
+			"pid": isValidPID,
+		}
+
+		valid := true
+		for _, key := range required {
+			value, ok := fields[key]
+			if !ok || !passportValidators[key](value) {
+				valid = false
+				break
+			}
+		}
+		if valid {
+			count++
+		}
+	}
+	return count
+}
+

internal/2020/DayFour/code_test.go

@@ -0,0 +1,27 @@
+package dayfour
+
+import "testing"
+
+var testInput = []string{
+	"ecl:gry pid:860033327 eyr:2020 hcl:#fffffd byr:1937 iyr:2017 cid:147 hgt:183cm",
+	"iyr:2013 ecl:amb cid:350 eyr:2023 pid:028048884 hcl:#cfa07d byr:1929",
+	"hcl:#ae17e1 iyr:2013 eyr:2024 ecl:brn pid:760753108 byr:1931 hgt:179cm",
+	"hcl:#cfa07d eyr:2025 pid:166559648 iyr:2011 ecl:brn hgt:59in",
+}
+
+func TestPartOne(t *testing.T) {
+	expected := 2
+	got := PartOne(testInput)
+	if got != expected {
+		t.Errorf("PartOne() = %d, want %d", got, expected)
+	}
+}
+
+func TestPartTwo(t *testing.T) {
+	expected := 2
+	got := PartTwo(testInput)
+	if got != expected {
+		t.Errorf("PartTwo() = %d, want %d", got, expected)
+	}
+}
+