module.exports = (sequelize, DataTypes) => {
    const Zone = sequelize.define('Zone', {
        id: {
            type: DataTypes.UUID,
            defaultValue: DataTypes.UUIDV4,
            primaryKey: true
        },
        name: {
            type: DataTypes.STRING,
            allowNull: false
        },
        regionId: {
            type: DataTypes.UUID,
            allowNull: false,
            references: {
                model: 'regions',
                key: 'id'
            }
        },
        zonalManagerId: {
            type: DataTypes.UUID,
            allowNull: true,
            references: {
                model: 'users',
                key: 'id'
            }
        }
    }, {
        tableName: 'zones',
        timestamps: true,
        indexes: [
            { fields: ['regionId'] },
            { unique: true, fields: ['name', 'regionId'] }
        ]
    });

    Zone.associate = (models) => {
        Zone.belongsTo(models.Region, {
            foreignKey: 'regionId',
            as: 'region'
        });
        Zone.belongsTo(models.User, {
            foreignKey: 'zonalManagerId',
            as: 'zonalManager'
        });
    };

    return Zone;
};