<?php
// Single player: Hangman. Guess the word, 6 lives.
// State persisted in sp_games (game='hangman').
require_once __DIR__ . '/../lib/bootstrap.php';
$me = require_login();

const H_WORDS = ['python', 'bbs', 'telnet', 'wml', 'matrix', 'linux', 'mastermind', 'screens', 'forum', 'games'];
const H_MAX_LIVES = 6;

function h_load(int $uid): ?array {
    $s = db()->prepare("SELECT * FROM sp_games WHERE user_id=? AND game='hangman'
                        AND status='active' ORDER BY id DESC LIMIT 1");
    $s->execute([$uid]);
    return $s->fetch() ?: null;
}
function h_new(int $uid): array {
    $word = H_WORDS[array_rand(H_WORDS)];
    $st = json_encode(['word' => $word, 'used' => [], 'lives' => H_MAX_LIVES]);
    $now = time();
    db()->prepare("INSERT INTO sp_games (game,user_id,state,created_at,updated_at)
                   VALUES ('hangman',?,?,?,?)")->execute([$uid, $st, $now, $now]);
    return h_load($uid);
}

$msg = ''; $done = false;
$g = h_load((int)$me['id']);

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    require_csrf();
    $act = $_POST['act'] ?? '';
    if ($act === 'new') {
        if ($g) db()->prepare("UPDATE sp_games SET status='abandoned' WHERE id=?")->execute([$g['id']]);
        $g = h_new((int)$me['id']);
        $msg = 'New game! I have chosen a word. Guess letters one at a time.';
    } else {
        if (!$g) $g = h_new((int)$me['id']);
        $st = json_decode($g['state'], true);
        $letter = strtolower((string)($_POST['letter'] ?? ''));
        if (strlen($letter) !== 1 || !ctype_alpha($letter)) {
            $msg = 'Please enter a single letter a-z.';
        } elseif (in_array($letter, $st['used'], true)) {
            $msg = 'You have already used that letter.';
        } else {
            $st['used'][] = $letter;
            if (in_array($letter, str_split($st['word']), true)) {
                $msg = 'Good! ' . $letter . ' is in the word.';
            } else {
                $st['lives']--;
                $msg = $letter . ' is not in the word.';
            }
            // Check win/loss
            $word_letters = array_diff(str_split($st['word']), $st['used']);
            if (empty($word_letters)) {
                $score = max(1, 50 - (H_MAX_LIVES - $st['lives']) * 5);
                db()->prepare("UPDATE sp_games SET status='won', state=?, updated_at=? WHERE id=?")
                    ->execute([json_encode($st), time(), $g['id']]);
                db()->prepare("INSERT INTO scores (game,user_id,score,detail,created_at)
                               VALUES ('hangman',?,?,?,?)")
                    ->execute([$me['id'], $score, $st['lives'] . ' lives left', time()]);
                $msg = "Yay! You guessed the word {$st['word']}! Score: $score";
                $done = true; $g = null;
            } elseif ($st['lives'] <= 0) {
                db()->prepare("UPDATE sp_games SET status='lost', state=?, updated_at=? WHERE id=?")
                    ->execute([json_encode($st), time(), $g['id']]);
                $msg = "You died! The word was {$st['word']}.";
                $done = true; $g = null;
            } else {
                db()->prepare("UPDATE sp_games SET state=?, updated_at=? WHERE id=?")
                    ->execute([json_encode($st), time(), $g['id']]);
                $g['state'] = json_encode($st);
            }
        }
    }
}

page_start('Hangman', ['back' => '/games.php']);
if ($msg) p_para($msg);
if ($g) {
    $st = json_decode($g['state'], true);
    $display = '';
    foreach (str_split($st['word']) as $ch) {
        $display .= (in_array($ch, $st['used'], true) ? $ch : '-') . ' ';
    }
    p_para('Word: ' . trim($display));
    p_para('Lives left: ' . $st['lives']);
    if ($st['used']) p_para('Used: ' . implode(', ', $st['used']));
    p_form('/games/hangman.php', [
        ['name' => 'letter', 'label' => 'Guess a letter', 'maxlength' => 1,
         'format' => '*A'],
    ], 'Guess');
} else {
    if (!$done) p_para('Guess the word one letter at a time. You have 6 lives.');
}
p_form('/games/hangman.php', [
    ['name' => 'act', 'type' => 'hidden', 'value' => 'new'],
], $g ? 'Restart' : 'New game');
p_links([['/games/scores.php', 'High scores', ['g' => 'hangman']], ['/games.php', 'Games']]);
page_end();