<?php
/**
 * CompanySettingManager — per-company key/value configuration store.
 *
 * Table: company_setting (company_id, setting_key, value, log, updated_at)
 *
 * Current keys:
 *   default_stock_status  int  0 = draft (manual approve required)
 *                              1 = auto-approve on save
 *
 * Designed to accept new keys without schema changes.
 */
class CompanySettingManager
{
    private PDO $pdo;
    private int $companyId;

    // ── Known keys with their defaults ───────────────────────────────────────
    private const DEFAULTS = [
        'default_stock_status' => 1,   // auto-approve by default
    ];

    public function __construct(PDO $pdo, int $companyId)
    {
        $this->pdo       = $pdo;
        $this->companyId = $companyId;
    }

    // ─────────────────────────────────────────────────────────────
    // Public API
    // ─────────────────────────────────────────────────────────────

    /**
     * Return the value for a single key, or the default if not configured.
     *
     * @param string $key  Setting key.
     * @return mixed       Stored value cast to int, or the default.
     */
    public function get(string $key): mixed
    {
        $sth = $this->pdo->prepare(
            "SELECT value FROM company_setting
             WHERE company_id = :company_id AND setting_key = :setting_key
             LIMIT 1"
        );
        $sth->execute([':company_id' => $this->companyId, ':setting_key' => $key]);
        $row = $sth->fetch(PDO::FETCH_ASSOC);

        if ($row === false) {
            return self::DEFAULTS[$key] ?? null;
        }

        // Cast numeric-looking values to int for clean comparisons
        return is_numeric($row['value']) ? (int)$row['value'] : $row['value'];
    }

    /**
     * Return all settings for this company, merged with defaults.
     *
     * @return array  Associative array of key => value.
     */
    public function getAll(): array
    {
        $sth = $this->pdo->prepare(
            "SELECT setting_key, value FROM company_setting
             WHERE company_id = :company_id"
        );
        $sth->execute([':company_id' => $this->companyId]);
        $rows = $sth->fetchAll(PDO::FETCH_KEY_PAIR);

        // Merge stored values over defaults, cast numeric values
        $result = self::DEFAULTS;
        foreach ($rows as $k => $v) {
            $result[$k] = is_numeric($v) ? (int)$v : $v;
        }
        return $result;
    }

    /**
     * Upsert a single setting value.
     *
     * @param string $key
     * @param mixed  $value
     */
    public function set(string $key, mixed $value): void
    {
        // Fetch existing log to append to it
        $sth = $this->pdo->prepare(
            "SELECT log FROM company_setting
             WHERE company_id = :company_id AND setting_key = :setting_key
             LIMIT 1"
        );
        $sth->execute([':company_id' => $this->companyId, ':setting_key' => $key]);
        $existing_log   = json_decode($sth->fetchColumn() ?: '[]', true) ?: [];
        $existing_log[] = [
            'user_id' => $_SESSION['login_user_id'] ?? null,
            'dt'      => date('Y-m-d H:i:s'),
            'value'   => $value,
        ];

        $this->pdo->prepare(
            "INSERT INTO company_setting (company_id, setting_key, value, log, updated_at)
             VALUES (:company_id, :setting_key, :value, :log, NOW())
             ON DUPLICATE KEY UPDATE value = VALUES(value), log = VALUES(log), updated_at = NOW()"
        )->execute([
            ':company_id'  => $this->companyId,
            ':setting_key' => $key,
            ':value'       => $value,
            ':log'         => json_encode($existing_log),
        ]);
    }

    /**
     * HTTP handler — read or update settings via AJAX.
     *
     * action: 'read'   → return all settings
     * action: 'update' → upsert one or more keys from $data
     *
     * @param array $data  Request data array.
     */
    public function handle(array $data): void
    {
        $action = $data['action'] ?? '';

        if ($action === 'read') {
            echo json_encode(['success' => 1, 'output' => $this->getAll()]);
            exit;
        }

        if ($action === 'update') {
            $allowed = array_keys(self::DEFAULTS);
            foreach ($allowed as $key) {
                $this->set($key, $data[$key] ?? self::DEFAULTS[$key]);
            }
            echo json_encode(['success' => 1, 'message' => 'Settings saved.']);
            exit;
        }

        http_response_code(400);
        echo json_encode(['success' => 0, 'message' => 'Invalid action.']);
        exit;
    }
}