package main

import (
	"os"
	"testing"

	"tangled.org/evan.jarrett.net/aoc2025/internal"
)

const testInput = `11-22,95-115,998-1012,1188511880-1188511890,222220-222224,1698522-1698528,446443-446449,38593856-38593862,565653-565659,824824821-824824827,2121212118-2121212124`

func TestPart1(t *testing.T) {
	d := &DayTwo{}
	if err := d.ParseInput(testInput); err != nil {
		t.Fatalf("ParseInput failed: %v", err)
	}

	got, err := d.Part1()
	if err != nil {
		t.Fatalf("Part1 failed: %v", err)
	}

	want := 1227775554
	if got != want {
		t.Errorf("Part1() = %d, want %d", got, want)
	}
}

func TestPart2(t *testing.T) {
	d := &DayTwo{}
	if err := d.ParseInput(testInput); err != nil {
		t.Fatalf("ParseInput failed: %v", err)
	}

	got, err := d.Part2()
	if err != nil {
		t.Fatalf("Part2 failed: %v", err)
	}

	want := 4174379265
	if got != want {
		t.Errorf("Part2() = %d, want %d", got, want)
	}
}

// getRealInput loads the real puzzle input, caching it to a file to avoid
// repeated network calls during benchmarks.
func getRealInput(b *testing.B) string {
	b.Helper()
	const cacheFile = "testdata/input.txt"

	// Try to read from cache first
	if data, err := os.ReadFile(cacheFile); err == nil {
		return string(data)
	}

	// Fetch from AOC and cache it
	input, err := internal.GetInput(2)
	if err != nil {
		b.Skipf("Could not fetch real input: %v", err)
	}

	// Cache for future runs
	_ = os.MkdirAll("testdata", 0755)
	_ = os.WriteFile(cacheFile, []byte(input), 0644)

	return input
}

func BenchmarkPart1(b *testing.B) {
	input := getRealInput(b)

	d := &DayTwo{}
	if err := d.ParseInput(input); err != nil {
		b.Fatalf("ParseInput failed: %v", err)
	}

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		d.Part1()
	}
}

func BenchmarkPart2(b *testing.B) {
	input := getRealInput(b)

	d := &DayTwo{}
	if err := d.ParseInput(input); err != nil {
		b.Fatalf("ParseInput failed: %v", err)
	}

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		d.Part2()
	}
}