<?php

namespace App\Service;

use App\Sim\Levels;
use JumPHP\Kernel\Engine;

/** What the player did: the levels open, the best rescue of each (var/progress.json). */
final class Progress
{
    /** the level being played (the pause menu restarts it) */
    public int $current = 0;
    private ?array $data = null;

    private function data(Engine $engine): array
    {
        return $this->data ??= (array)$engine->storage->readJson('progress.json', []) + ['unlocked' => 1, 'best' => []];
    }

    public function unlocked(Engine $engine): int
    {
        return max(1, min(Levels::count(), (int)$this->data($engine)['unlocked']));
    }

    /** Best percentage saved on a level (0-based), null: never won. */
    public function best(Engine $engine, int $level): ?int
    {
        $best = $this->data($engine)['best'][(string)$level] ?? null;
        return $best === null ? null : (int)$best;
    }

    public function won(Engine $engine, int $level, int $percent): void
    {
        $data = $this->data($engine);
        $data['best'][(string)$level] = max((int)($data['best'][(string)$level] ?? 0), $percent);
        $data['unlocked'] = max((int)$data['unlocked'], min(Levels::count(), $level + 2));
        $this->data = $data;
        $engine->storage->writeJson('progress.json', $data);
    }

    /** 1 to 3 stars for a rescue percentage against what the level asked. */
    public static function stars(int $percent, int $needPercent): int
    {
        return $percent >= 100 ? 3 : ($percent >= ($needPercent + 100) / 2 ? 2 : 1);
    }
}