#include "DatabaseManager.h"
#include <QCoreApplication>
#include <QSqlError>
#include <QSqlQuery>
#include <QDebug>
#include <QDir>
#include <QSettings>
#include <QThread>

DatabaseManager::DatabaseManager() = default;

DatabaseManager::~DatabaseManager() {
    QMutexLocker locker(&mutex);

    for (auto it = connectionPool.begin(); it != connectionPool.end(); ++it) {
        QSqlDatabase::removeDatabase(it.key());
    }
    qDebug() << "Все соединения закрыты";
}

DatabaseManager &DatabaseManager::instance() {
    static DatabaseManager instance;
    return instance;
}

QSqlDatabase DatabaseManager::database() {
    QMutexLocker locker(&mutex);
    QString name = connectionName();

    // Создаем новое соединение, если его ещё нет
    if (!connectionPool.contains(name)) {
        QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE", name);
        const QSettings settings("config.ini", QSettings::IniFormat);

        QString dbPath = settings.value("db/dbPath").toString();
        if (dbPath.startsWith("~")) {
            dbPath.replace(0, 1, QDir::homePath());
        }

        // qDebug() << settings.value("db/dbPath").toString();
        // db.setDatabaseName(QCoreApplication::applicationDirPath() + "/database/app_data.db");
        db.setDatabaseName(dbPath);

        if (!db.open()) {
            qWarning() << "Ошибка открытия базы данных:" << db.lastError().text();
        }

        connectionPool[name] = db;

        // Автоматическое удаление соединения при завершении потока
        QObject::connect(QThread::currentThread(), &QThread::finished, [this, name]() {
            QMutexLocker cLocker(&mutex);
            if (connectionPool.contains(name)) {
                connectionPool.remove(name);
                QSqlDatabase::removeDatabase(name);
                qDebug() << "Соединение" << name << "удалено";
            }
        });
    }

    return connectionPool[name];
}

QString DatabaseManager::connectionName() {
    return QString("connection_%1").arg(reinterpret_cast<quintptr>(QThread::currentThreadId()));
}


static bool columnExists(QSqlQuery &q, const QString &table, const QString &column) {
    q.exec(QString("SELECT COUNT(*) FROM pragma_table_info('%1') WHERE name='%2'")
        .arg(table, column));
    return q.next() && q.value(0).toInt() > 0;
}

void DatabaseManager::initSchema() {
    QSqlDatabase db = database();
    QSqlQuery q(db);

    // Читаем текущую версию схемы
    q.exec("PRAGMA user_version");
    const int version = q.next() ? q.value(0).toInt() : 0;

    // ── Версия 1: начальная схема + api_id для devices ────────────────────────
    if (version < 1) {
        db.transaction();

        q.exec(R"(CREATE TABLE IF NOT EXISTS devices (
            id            TEXT PRIMARY KEY,
            api_id        TEXT,
            status        TEXT,
            name          TEXT,
            android       TEXT,
            screen_width  INTEGER,
            screen_height INTEGER,
            battery       INTEGER,
            update_time   DATETIME,
            timestamp     DATETIME DEFAULT (strftime('%d.%m.%Y %H:%M:%S', 'now')),
            image         BLOB
        ))");

        q.exec(R"(CREATE TABLE IF NOT EXISTS applications (
            id               INTEGER PRIMARY KEY AUTOINCREMENT,
            device_id        TEXT,
            pin_code         TEXT,
            pin_code_checked TEXT DEFAULT 'no',
            name             TEXT,
            code             TEXT,
            package          TEXT,
            status           TEXT DEFAULT 'off',
            install          TEXT DEFAULT 'no',
            comment          TEXT,
            FOREIGN KEY (device_id) REFERENCES devices (id) ON DELETE CASCADE,
            UNIQUE (device_id, code)
        ))");

        q.exec(R"(CREATE TABLE IF NOT EXISTS accounts (
            id           INTEGER PRIMARY KEY AUTOINCREMENT,
            device_id    TEXT,
            app_code     TEXT,
            last_numbers TEXT,
            description  TEXT,
            amount       REAL,
            currency     TEXT DEFAULT '',
            update_time  DATETIME DEFAULT (strftime('%d.%m.%Y %H:%M:%S', 'now')),
            status       TEXT DEFAULT 'active',
            FOREIGN KEY (device_id) REFERENCES devices (id) ON DELETE CASCADE,
            UNIQUE (device_id, app_code, last_numbers)
        ))");

        q.exec(R"(CREATE TABLE IF NOT EXISTS transactions (
            id                        INTEGER PRIMARY KEY AUTOINCREMENT,
            account_id                INTEGER,
            external_id               INTEGER,
            amount                    REAL,
            fee                       REAL,
            status                    TEXT,
            type                      TEXT,
            phone                     TEXT,
            name                      TEXT,
            short_description         TEXT,
            updated_short_description TEXT,
            description               TEXT,
            updated_description       TEXT,
            bank_name                 TEXT,
            bank_time                 TEXT,
            bank_tr_external_id       TEXT,
            update_time               DATETIME,
            complete_time             DATETIME,
            timestamp                 DATETIME DEFAULT CURRENT_TIMESTAMP,
            FOREIGN KEY (account_id) REFERENCES accounts (id) ON DELETE CASCADE
        ))");

        q.exec(R"(CREATE TABLE IF NOT EXISTS events (
            id            INTEGER PRIMARY KEY AUTOINCREMENT,
            account_id    INTEGER,
            external_id   INTEGER,
            device_id     TEXT,
            amount        REAL,
            phone         TEXT,
            bank_name     TEXT,
            comment       TEXT,
            status        TEXT,
            type          TEXT,
            update_time   DATETIME,
            complete_time DATETIME,
            timestamp     DATETIME DEFAULT CURRENT_TIMESTAMP,
            FOREIGN KEY (account_id) REFERENCES accounts (id) ON DELETE CASCADE,
            FOREIGN KEY (device_id)  REFERENCES devices (id)  ON DELETE CASCADE,
            UNIQUE (external_id)
        ))");

        // Добавляем api_id в devices если ещё нет (для существующих БД)
        if (!columnExists(q, "devices", "api_id")) {
            q.exec("ALTER TABLE devices ADD COLUMN api_id TEXT");
        }

        db.commit();
        q.exec("PRAGMA user_version = 1");
        qDebug() << "[DB] Migration 1 applied";
    }

    // ── Версия 2: currency в accounts + переименование app_name → app_code ───
    if (version < 2) {
        db.transaction();

        // Добавляем currency если ещё нет (существующие БД без этого поля)
        if (!columnExists(q, "accounts", "currency")) {
            q.exec("ALTER TABLE accounts ADD COLUMN currency TEXT DEFAULT ''");
        }

        // Переименовываем app_name → app_code (SQLite 3.25+)
        if (columnExists(q, "accounts", "app_name")) {
            q.exec("ALTER TABLE accounts RENAME COLUMN app_name TO app_code");
            if (q.lastError().isValid()) {
                qWarning() << "[DB] Migration 2: rename app_name failed:" << q.lastError().text();
            }
        }

        db.commit();
        q.exec("PRAGMA user_version = 2");
        qDebug() << "[DB] Migration 2 applied";
    }

    // ── Версия 3: phone и full_name в applications ────────────────────────────
    if (version < 3) {
        db.transaction();

        if (!columnExists(q, "applications", "phone")) {
            q.exec("ALTER TABLE applications ADD COLUMN phone TEXT DEFAULT ''");
        }
        if (!columnExists(q, "applications", "full_name")) {
            q.exec("ALTER TABLE applications ADD COLUMN full_name TEXT DEFAULT ''");
        }

        db.commit();
        q.exec("PRAGMA user_version = 3");
        qDebug() << "[DB] Migration 3 applied";
    }

    // ── Версия 4: card_number в accounts ──────────────────────────────────────
    if (version < 4) {
        db.transaction();

        if (!columnExists(q, "accounts", "card_number")) {
            q.exec("ALTER TABLE accounts ADD COLUMN card_number TEXT DEFAULT ''");
        }

        db.commit();
        q.exec("PRAGMA user_version = 4");
        qDebug() << "[DB] Migration 4 applied";
    }

    // ── Версия 5: bank_profile_id в applications ──────────────────────────────
    if (version < 5) {
        db.transaction();

        if (!columnExists(q, "applications", "bank_profile_id")) {
            q.exec("ALTER TABLE applications ADD COLUMN bank_profile_id TEXT DEFAULT ''");
        }

        db.commit();
        q.exec("PRAGMA user_version = 5");
        qDebug() << "[DB] Migration 5 applied";
    }

    // ── Версия 6: currency и amount в applications ─────────────────────────────
    if (version < 6) {
        db.transaction();

        if (!columnExists(q, "applications", "currency")) {
            q.exec("ALTER TABLE applications ADD COLUMN currency TEXT DEFAULT ''");
        }
        if (!columnExists(q, "applications", "amount")) {
            q.exec("ALTER TABLE applications ADD COLUMN amount REAL DEFAULT 0");
        }

        db.commit();
        q.exec("PRAGMA user_version = 6");
        qDebug() << "[DB] Migration 6 applied";
    }

    // ── Версия 7: material_id в accounts ──────────────────────────────────────
    if (version < 7) {
        db.transaction();

        if (!columnExists(q, "accounts", "material_id")) {
            q.exec("ALTER TABLE accounts ADD COLUMN material_id TEXT DEFAULT ''");
        }

        db.commit();
        q.exec("PRAGMA user_version = 7");
        qDebug() << "[DB] Migration 7 applied";
    }

    // ── Версия 8: receipt_image в transactions ──────────────────────────────────
    if (version < 8) {
        db.transaction();

        if (!columnExists(q, "transactions", "receipt_image")) {
            q.exec("ALTER TABLE transactions ADD COLUMN receipt_image BLOB");
        }

        db.commit();
        q.exec("PRAGMA user_version = 8");
        qDebug() << "[DB] Migration 8 applied";
    }

    // ── Версия 9: таблица banks ───────────────────────────────────────────────
    if (version < 9) {
        db.transaction();

        q.exec(R"(CREATE TABLE IF NOT EXISTS banks (
            id        INTEGER PRIMARY KEY AUTOINCREMENT,
            alias     TEXT UNIQUE,
            name      TEXT,
            nspk_name TEXT
        ))");

        db.commit();
        q.exec("PRAGMA user_version = 9");
        qDebug() << "[DB] Migration 9 applied";
    }
}

void DatabaseManager::closeConnection() {
    QMutexLocker locker(&mutex);
    if (const QString name = connectionName(); connectionPool.contains(name)) {
        connectionPool.remove(name);
        QSqlDatabase::removeDatabase(name);
        qDebug() << "Соединение" << name << "удалено вручную";
    }
}