<?php
declare(strict_types=1);

class ConversationContext
{
    public static function getOrCreate(int $companyId, string $phoneNumber, string $botType = 'normal'): array
    {
        $stmt = db()->prepare("SELECT * FROM bot_context WHERE company_id = ? AND phone_number = ? LIMIT 1");
        $stmt->execute([$companyId, $phoneNumber]);
        $ctx = $stmt->fetch();

        if ($ctx) {
            return $ctx;
        }

        $stmt = db()->prepare("INSERT INTO bot_context (company_id, phone_number, bot_type, ai_history, metadata) VALUES (?, ?, ?, '[]', '{}')");
        $stmt->execute([$companyId, $phoneNumber, $botType]);

        return [
            'id'           => (int)db()->lastInsertId(),
            'company_id'   => $companyId,
            'phone_number' => $phoneNumber,
            'bot_type'     => $botType,
            'current_node' => null,
            'ai_history'   => '[]',
            'metadata'     => '{}',
        ];
    }

    public static function updateNode(int $id, ?string $node): void
    {
        $stmt = db()->prepare("UPDATE bot_context SET current_node = ?, updated_at = NOW() WHERE id = ?");
        $stmt->execute([$node, $id]);
    }

    public static function addAiMessage(int $id, array $message): void
    {
        $stmt = db()->prepare("SELECT ai_history FROM bot_context WHERE id = ? LIMIT 1");
        $stmt->execute([$id]);
        $row = $stmt->fetch();

        $history = $row ? json_decode($row['ai_history'], true) : [];

        $history[] = $message;

        if (count($history) > 50) {
            array_shift($history);
        }

        $stmt = db()->prepare("UPDATE bot_context SET ai_history = ?, updated_at = NOW() WHERE id = ?");
        $stmt->execute([json_encode($history), $id]);
    }

    public static function getAiHistory(int $id): array
    {
        $stmt = db()->prepare("SELECT ai_history FROM bot_context WHERE id = ? LIMIT 1");
        $stmt->execute([$id]);
        $row = $stmt->fetch();
        return $row ? json_decode($row['ai_history'], true) ?? [] : [];
    }

    public static function updateMetadata(int $id, array $metadata): void
    {
        $stmt = db()->prepare("UPDATE bot_context SET metadata = ?, updated_at = NOW() WHERE id = ?");
        $stmt->execute([json_encode($metadata), $id]);
    }

    public static function getMetadata(int $id): array
    {
        $stmt = db()->prepare("SELECT metadata FROM bot_context WHERE id = ? LIMIT 1");
        $stmt->execute([$id]);
        $row = $stmt->fetch();
        return $row ? json_decode($row['metadata'], true) ?? [] : [];
    }

    public static function reset(int $id): void
    {
        $stmt = db()->prepare("UPDATE bot_context SET current_node = NULL, ai_history = '[]', metadata = '{}', updated_at = NOW() WHERE id = ?");
        $stmt->execute([$id]);
    }
}