// See the file "COPYING" in the main distribution directory for copyright.

#pragma once

#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <sys/types.h>

#include "zeek/Type.h"
#include "zeek/net_util.h"

namespace zeek::detail {
class SerializationFormat;
}

namespace zeek::threading {

/**
 * Definition of a log file, i.e., one column of a log stream.
 */
struct Field {
    const char* name = nullptr; //! Name of the field.
    //! Needed by input framework. Port fields have two names (one for the
    //! port, one for the type), and this specifies the secondary name.
    const char* secondary_name = nullptr;
    TypeTag type = TYPE_ERROR;    //! Type of the field.
    TypeTag subtype = TYPE_ERROR; //! Inner type for sets and vectors.
    bool optional = false;        //! True if field is optional.


    /**
     * Constructor.
     *
     * For Read() usage. Initializes with TYPE_ERROR.
     */
    Field() = default;

    /**
     * Constructor.
     */
    Field(const char* name, const char* secondary_name, TypeTag type, TypeTag subtype, bool optional)
        : name(util::copy_string(name)),
          secondary_name(util::copy_string(secondary_name)),
          type(type),
          subtype(subtype),
          optional(optional) {}

    /**
     * Copy constructor.
     */
    Field(const Field& other)
        : name(util::copy_string(other.name)),
          secondary_name(util::copy_string(other.secondary_name)),
          type(other.type),
          subtype(other.subtype),
          optional(other.optional) {}

    /**
     * Move constructor.
     */
    Field(Field&& other) noexcept {
        name = other.name;
        secondary_name = other.secondary_name;
        type = other.type;
        subtype = other.subtype;
        optional = other.optional;

        other.name = nullptr;
        other.secondary_name = nullptr;
        other.type = TYPE_ERROR;
        other.subtype = TYPE_ERROR;
        other.optional = false;
    }

    ~Field() {
        delete[] name;
        delete[] secondary_name;
    }

    Field& operator=(const Field& other) {
        if ( this != &other ) {
            delete[] name;
            delete[] secondary_name;
            name = util::copy_string(other.name);
            secondary_name = util::copy_string(other.secondary_name);
            type = other.type;
            subtype = other.subtype;
            optional = other.optional;
        }

        return *this;
    }

    /**
     * Unserializes a field.
     *
     * @param fmt The serialization format to use. The format handles
     * low-level I/O.
     *
     * @return False if an error occurred.
     */
    bool Read(zeek::detail::SerializationFormat* fmt);

    /**
     * Serializes a field.
     *
     * @param fmt The serialization format to use. The format handles
     * low-level I/O.
     *
     * @return False if an error occurred.
     */
    bool Write(zeek::detail::SerializationFormat* fmt) const;

    /**
     * Returns a textual description of the field's type. This method is
     * thread-safe.
     */
    std::string TypeName() const;
};

/**
 * Definition of a log value, i.e., a entry logged by a stream.
 *
 * This struct essentially represents a serialization of a Val instance (for
 * those Vals supported).
 */
struct Value {
    TypeTag type;    //! The type of the value.
    TypeTag subtype; //! Inner type for sets and vectors.

    struct set_t {
        zeek_int_t size;
        Value** vals;
    };
    using vec_t = set_t;
    struct port_t {
        zeek_uint_t port;
        TransportProto proto;
        constexpr size_t size() { return sizeof(port) + sizeof(proto); }
    };

    struct addr_t {
        IPFamily family;
        union {
            struct in_addr in4;
            struct in6_addr in6;
        } in;

        constexpr size_t size() { return sizeof(in) + sizeof(IPFamily); }
    };

    // A small note for handling subnet values: Subnet values emitted from
    // the logging framework will always have a length that is based on the
    // internal IPv6 representation (so you have to subtract 96 from it to
    // get the correct value for IPv4).
    // However, the Input framework expects the "normal" length for an IPv4
    // address (so do not add 96 to it), because the underlying constructors
    // for the SubNet type want it like this.
    struct subnet_t {
        addr_t prefix;
        uint8_t length;
        constexpr size_t size() { return prefix.size() + sizeof(length); }
    };

    /**
     * This union is a subset of the "underlying" values in Val subclasses,
     * including only the types we can log directly. See IsCompatibleType().
     */
    union _val {
        zeek_int_t int_val;
        zeek_uint_t uint_val;
        port_t port_val;
        double double_val;
        set_t set_val;
        vec_t vector_val;
        addr_t addr_val;
        subnet_t subnet_val;
        const char* pattern_text_val;

        struct {
            char* data;
            int length;
        } string_val;

        _val() { memset(this, 0, sizeof(_val)); }
    } val;

    bool present = false; //! False for optional record fields that are not set.

    /**
     * Constructor.
     *
     * arg_type: The type of the value.
     *
     * arg_present: False if the value represents an optional record field
     * that is not set.
     */
    Value(TypeTag arg_type = TYPE_ERROR, bool arg_present = true)
        : type(arg_type), subtype(TYPE_VOID), present(arg_present) {}

    /**
     * Constructor.
     *
     * arg_type: The type of the value.
     *
     * arg_type: The subtype of the value for sets and vectors.
     *
     * arg_present: False if the value represents an optional record field
     * that is not set.
     */
    Value(TypeTag arg_type, TypeTag arg_subtype, bool arg_present = true)
        : type(arg_type), subtype(arg_subtype), present(arg_present) {}

    /**
     * Copy constructor.
     */
    Value(const Value& other);

    /**
     * Move constructor.
     */
    Value(Value&& other) noexcept;

    /**
     * Destructor.
     */
    ~Value();

    /**
     * Unserializes a value.
     *
     * @param fmt The serialization format to use. The format handles low-level I/O.
     *
     * @return False if an error occurred.
     */
    bool Read(zeek::detail::SerializationFormat* fmt);

    /**
     * Serializes a value.
     *
     * @param fmt The serialization format to use. The format handles
     * low-level I/O.
     *
     * @return False if an error occurred.
     */
    bool Write(zeek::detail::SerializationFormat* fmt) const;

    /**
     * Returns true if the type can be represented by a Value. If
     * `atomic_only` is true, will not permit composite types. This
     * method is thread-safe. */
    static bool IsCompatibleType(Type* t, bool atomic_only = false);

    /**
     * Convenience function to delete an array of value pointers.
     * @param vals Array of values
     * @param num_fields Number of members
     */
    static void delete_value_ptr_array(Value** vals, int num_fields);

    /**
     * Convert threading::Value to an internal Zeek type, just using the information given in the
     * threading::Value.
     *
     * @param source Name of the source of this threading value. This is used for warnings that are
     * raised in case an error occurs.
     * @param val Threading Value to convert to a Zeek Val.
     * @param have_error Reference to a boolean. This should be set to false when passed in and is
     * set to true in case an error occurs. If this is set to false when the function is called, the
     * function immediately aborts.
     * @return Val representation of the threading::Value. nullptr on error.
     */
    static Val* ValueToVal(const std::string& source, const threading::Value* val, bool& have_error);

    void SetFileLineNumber(int line) { line_number = line; }
    int GetFileLineNumber() const { return line_number; }

private:
    friend class IPAddr;

    // For values read by the input framework, this can represent the line number
    // containing this value. Used by the Ascii reader primarily.
    int line_number = -1;
};

} // namespace zeek::threading
