attack_type.hpp

Go to the documentation of this file.

/*
    Copyright (C) 2003 - 2025
    by David White <dave@whitevine.net>
    Part of the Battle for Wesnoth Project https://www.wesnoth.org/
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY.
 
    See the COPYING file for more details.
*/
 
#pragma once
 
#include "map/location.hpp"
#include "tstring.hpp"
#include "config.hpp"
#include <string>
#include <vector>
 
#include <boost/iterator/indirect_iterator.hpp>
#include <boost/dynamic_bitset_fwd.hpp>
 
#include "units/ptr.hpp" // for attack_ptr
#include "units/unit_alignments.hpp"
 
class unit_ability_list;
class unit_type;
namespace wfl {
    class map_formula_callable;
}
//the 'attack type' is the type of attack, how many times it strikes,
//and how much damage it does.
class attack_type : public std::enable_shared_from_this<attack_type>
{
public:
 
    explicit attack_type(const config& cfg);
    const t_string& name() const { return description_; }
    const std::string& id() const { return id_; }
    const std::string& type() const { return type_; }
    const std::string& icon() const { return icon_; }
    const std::string& range() const { return range_; }
    int min_range() const { return min_range_; }
    int max_range() const { return max_range_; }
    std::string accuracy_parry_description() const;
    std::string accuracy_parry_tooltip() const;
    int accuracy() const { return accuracy_; }
    int parry() const { return parry_; }
    int damage() const { return damage_; }
    int num_attacks() const { return num_attacks_; }
    double attack_weight() const { return attack_weight_; }
    double defense_weight() const { return defense_weight_; }
    const config &specials() const { return specials_; }
 
    void set_name(const t_string& value) { description_  = value; set_changed(true); }
    void set_id(const std::string& value) { id_ = value; set_changed(true); }
    void set_type(const std::string& value) { type_ = value; set_changed(true); }
    void set_icon(const std::string& value) { icon_ = value; set_changed(true); }
    void set_range(const std::string& value) { range_ = value; set_changed(true); }
    void set_min_range(int value) { min_range_ = value; set_changed(true); }
    void set_max_range(int value) { max_range_ = value; set_changed(true); }
    void set_attack_alignment(const std::string& value) { alignment_ = unit_alignments::get_enum(value); set_changed(true); }
    void set_accuracy(int value) { accuracy_ = value; set_changed(true); }
    void set_parry(int value) { parry_ = value; set_changed(true); }
    void set_damage(int value) { damage_ = value; set_changed(true); }
    void set_num_attacks(int value) { num_attacks_ = value; set_changed(true); }
    void set_attack_weight(double value) { attack_weight_ = value; set_changed(true); }
    void set_defense_weight(double value) { defense_weight_ = value; set_changed(true); }
    void set_specials(config value) { specials_ = value; set_changed(true); }
 
 
    // In unit_abilities.cpp:
 
    /**
     * @return True iff the special @a special is active.
     * @param special The special being checked.
     * @param simple_check If true, check whether the unit has the special. Else, check whether the special is currently active.
     */
    bool has_special(const std::string& special, bool simple_check = false) const;
    unit_ability_list get_specials(const std::string& special) const;
    std::vector<std::pair<t_string, t_string>> special_tooltips(boost::dynamic_bitset<>* active_list = nullptr) const;
    std::vector<std::pair<t_string, t_string>> abilities_special_tooltips(boost::dynamic_bitset<>* active_list) const;
    std::string weapon_specials() const;
    std::string weapon_specials_value(const std::set<std::string>& checking_tags) const;
 
    /** Returns alignment specified by alignment_ variable.
     */
    utils::optional<unit_alignments::type> alignment() const { return alignment_; }
    /** Returns alignment specified by alignment() for filtering when exist.
     */
    std::string alignment_str() const { return alignment_ ? unit_alignments::get_string(*alignment_) : ""; }
 
    /** Calculates the number of attacks this weapon has, considering specials. */
    void modified_attacks(unsigned & min_attacks,
                          unsigned & max_attacks) const;
 
    /** @return A type()/replacement_type and a list of alternative_types that should be displayed in the selected unit's report. */
    std::pair<std::string, std::set<std::string>> damage_types() const;
    /** @return The type of attack used and the resistance value that does the most damage. */
    std::pair<std::string, int> effective_damage_type() const;
 
    /** Returns the damage per attack of this weapon, considering specials. */
    double modified_damage() const;
    /** Return the defense value, considering specials.
     * @param cth The chance_to_hit value modified or not by function.
     * @param special_only Decide if get_specials() or get_specials_and_abilities()should be used.
     */
    int modified_chance_to_hit(int cth, bool special_only = false) const;
 
    /** Return the special weapon value, considering specials.
     * @param abil_list The list of special checked.
     * @param base_value The value modified or not by function.
     */
    int composite_value(const unit_ability_list& abil_list, int base_value) const;
    /** Returns list for weapon like abilities for each ability type. */
    unit_ability_list get_weapon_ability(const std::string& ability) const;
    /**
     * @param special the tag name to check for
     * @return list which contains get_weapon_ability and get_specials list for each ability type, with overwritten items removed
     */
    unit_ability_list get_specials_and_abilities(const std::string& special) const;
    /** used for abilities used like weapon and true specials
     * @return True if the ability @a special is active.
     * @param special The special being checked.
     */
    bool has_special_or_ability(const std::string& special) const;
    /** check if special matche
     * @return True if special matche with filter(if 'active' filter is true, check if special active).
     * @param simple_check If true, check whether the unit has the special. Else, check whether the special is currently active.
     * @param filter contain attributes to check(special_id, special_type etc...).
     */
    bool has_filter_special_or_ability(const config& filter, bool simple_check = false) const;
    /**
     * Returns true if this is a dummy attack_type, for example the placeholder that the unit_attack dialog
     * uses when a defender has no weapon for a given range.
     */
    bool attack_empty() const {return (id().empty() && name().empty() && type().empty() && range().empty());}
    /** remove special if matche condition
     * @param filter if special check with filter, it will be removed.
     */
    void remove_special_by_filter(const config& filter);
    /** check if special matche
     * @return True if special matche with filter(if 'active' filter is true, check if special active).
     * @param filter if special check with filter, return true.
     */
    bool has_special_or_ability_with_filter(const config & filter) const;
 
    // In unit_types.cpp:
 
    bool matches_filter(const config& filter, const std::string& check_if_recursion = "") const;
 
    /** Applies effect modifications described by @a cfg. */
    void apply_effect(const config& cfg);
 
    /**
     * Generates a description of the effect specified by @a cfg, if applicable.
     * This covers a subset of the effects which can be applied via @ref apply_effect.
     */
    static std::string describe_effect(const config& cfg);
 
    int movement_used() const { return movement_used_; }
    void set_movement_used(int value) { movement_used_ = value; }
    int attacks_used() const { return attacks_used_; }
    void set_attacks_used(int value) { attacks_used_ = value; }
 
    void write(config& cfg) const;
    inline config to_config() const { config c; write(c); return c; }
 
    void add_formula_context(wfl::map_formula_callable&) const;
 
    /**
     * Helper similar to std::unique_lock for detecting when calculations such as has_special
     * have entered infinite recursion.
     *
     * This assumes that there's only a single thread accessing the attack_type, it's a lightweight
     * increment/decrement counter rather than a mutex.
     */
    class recursion_guard {
        friend class attack_type;
        /**
         * Only expected to be called in update_variables_recursion(), which handles some of the checks.
         */
        explicit recursion_guard(const attack_type& weapon, const config& special);
    public:
        /**
         * Construct an empty instance, only useful for extending the lifetime of a
         * recursion_guard returned from weapon.update_variables_recursion() by
         * std::moving it to an instance declared in a larger scope.
         */
        explicit recursion_guard();
 
        /**
         * Returns true if a level of recursion was available at the time when update_variables_recursion()
         * created this object.
         */
        operator bool() const;
 
        recursion_guard(recursion_guard&& other) noexcept;
        recursion_guard(const recursion_guard& other) = delete;
        recursion_guard& operator=(recursion_guard&&) noexcept;
        recursion_guard& operator=(const recursion_guard&) = delete;
        ~recursion_guard();
    private:
        std::shared_ptr<const attack_type> parent;
    };
 
    /**
     * Tests which might otherwise cause infinite recursion should call this, check that the
     * returned object evaluates to true, and then keep the object returned as long as the
     * recursion might occur, similar to a reentrant mutex that's limited to a small number of
     * reentrances.
     *
     * This only expects to be called in a single thread, but the whole of attack_type makes
     * that assumption, for example its' mutable members are assumed to be set up by the current
     * caller (or caller's caller, probably several layers up).
     */
    recursion_guard update_variables_recursion(const config& special) const;
 
private:
    // In unit_abilities.cpp:
 
    // Configured as a bit field, in case that is useful.
    enum AFFECTS { AFFECT_SELF=1, AFFECT_OTHER=2, AFFECT_EITHER=3 };
    /**
     * Filter a list of abilities or weapon specials
     * @param cfg config of ability checked
     * @param tag_name le type of ability who is checked
     * @param filter config contain list of attribute who are researched in cfg
     *
     * @return true if all attribute with ability checked
     */
    bool special_matches_filter(const config & cfg, const std::string& tag_name, const config & filter) const;
    /**
     * Select best damage type based on frequency count for replacement_type.
     *
     * @param damage_type_list list of [damage_type] to check.
     */
    std::string select_replacement_type(const unit_ability_list& damage_type_list) const;
    /**
     * Select best damage type based on highest damage for alternative_type.
     *
     * @param damage_type_list list of [damage_type] to check.
     * @param resistance_list list of "resistance" abilities to check for each type of damage checked.
     */
    std::pair<std::string, int> select_alternative_type(const unit_ability_list& damage_type_list, const unit_ability_list& resistance_list) const;
    /**
     * Filter a list of abilities or weapon specials, removing any entries that don't own
     * the overwrite_specials attributes.
     *
     * @param overwriters list that may have overwrite_specials attributes.
     * @param tag_name type of abilitie/special checked.
     */
    unit_ability_list overwrite_special_overwriter(unit_ability_list overwriters, const std::string& tag_name) const;
    /**
     * Check whether @a cfg would be overwritten by any element of @a overwriters.
     *
     * @return True if element checked is overwritable.
     * @param overwriters list used for check if element is overwritable.
     * @param cfg element checked.
     * @param tag_name type of abilitie/special checked.
     */
    bool overwrite_special_checking(unit_ability_list& overwriters, const config& cfg, const std::string& tag_name) const;
 
    bool special_active(const config& special, AFFECTS whom, const std::string& tag_name,
                        bool in_abilities_tag = false) const;
 
    bool special_tooltip_active(const config& special, const std::string& tag_name) const;
/** weapon_specials_impl_self and weapon_specials_impl_adj : check if special name can be added.
     * @param[in,out] temp_string the string modified and returned
     * @param[in] self the unit checked.
     * @param[in] self_attack the attack used by unit checked in this function.
     * @param[in] other_attack the attack used by opponent to unit checked.
     * @param[in] self_loc location of the unit checked.
     * @param[in] whom determine if unit affected or not by special ability.
     * @param[in,out] checking_name the reference for checking if a name is already added
     * @param[in] checking_tags the reference for checking if special ability type can be used
     * @param[in] leader_bool If true, [leadership] abilities are checked.
     */
    static void weapon_specials_impl_self(
        std::string& temp_string,
        const unit_const_ptr& self,
        const const_attack_ptr& self_attack,
        const const_attack_ptr& other_attack,
        const map_location& self_loc,
        AFFECTS whom,
        std::set<std::string>& checking_name,
        const std::set<std::string>& checking_tags={},
        bool leader_bool=false
    );
 
    static void weapon_specials_impl_adj(
        std::string& temp_string,
        const unit_const_ptr& self,
        const const_attack_ptr& self_attack,
        const const_attack_ptr& other_attack,
        const map_location& self_loc,
        AFFECTS whom,
        std::set<std::string>& checking_name,
        const std::set<std::string>& checking_tags={},
        const std::string& affect_adjacents="",
        bool leader_bool=false
    );
    /** check_self_abilities_impl : return an boolean value for checking of activities of abilities used like weapon
     * @return True if the special @a tag_name is active.
     * @param self_attack the attack used by unit checked in this function.
     * @param other_attack the attack used by opponent to unit checked.
     * @param special the config to one special ability checked.
     * @param u the unit checked.
     * @param loc location of the unit checked.
     * @param whom determine if unit affected or not by special ability.
     * @param tag_name The special ability type who is being checked.
     * @param leader_bool If true, [leadership] abilities are checked.
     */
    static bool check_self_abilities_impl(
        const const_attack_ptr& self_attack,
        const const_attack_ptr& other_attack,
        const config& special,
        const unit_const_ptr& u,
        const map_location& loc,
        AFFECTS whom,
        const std::string& tag_name,
        bool leader_bool=false
    );
 
 
    /** check_adj_abilities_impl : return an boolean value for checking of activities of abilities used like weapon in unit adjacent to fighter
     * @return True if the special @a tag_name is active.
     * @param self_attack the attack used by unit who fight.
     * @param other_attack the attack used by opponent.
     * @param special the config to one special ability checked.
     * @param u the unit who is or not affected by an abilities owned by @a from.
     * @param from unit distant to @a u is checked.
     * @param dist distance between unit distant and @a u.
     * @param dir direction to research a unit distant to @a u.
     * @param loc location of the unit checked.
     * @param from_loc location of the unit distant to @a u.
     * @param whom determine if unit affected or not by special ability.
     * @param tag_name The special ability type who is being checked.
     * @param leader_bool If true, [leadership] abilities are checked.
     */
    static bool check_adj_abilities_impl(
        const const_attack_ptr& self_attack,
        const const_attack_ptr& other_attack,
        const config& special,
        const unit_const_ptr& u,
        const unit& from,
        std::size_t dist,
        int dir,
        const map_location& loc,
        const map_location& from_loc,
        AFFECTS whom,
        const std::string& tag_name,
        bool leader_bool = false
    );
 
    static bool special_active_impl(
        const const_attack_ptr& self_attack,
        const const_attack_ptr& other_attack,
        const config& special,
        AFFECTS whom,
        const std::string& tag_name,
        bool in_abilities_tag = false
    );
 
    /** has_ability_impl : return an boolean value for checking of activities of abilities used like weapon
     * @return True if  @a special is active.
     * @param self_attack the attack used by unit who fight.
     * @param other_attack the attack used by opponent.
     * @param self the unit who fight.
     * @param self_loc location of @a self.
     * @param whom determine if unit affected or not by special ability.
     * @param special The special ability type who is being checked.
     */
    static bool has_ability_impl(
        const const_attack_ptr& self_attack,
        const unit_const_ptr& self,
        const map_location& self_loc,
        const const_attack_ptr& other_attack,
        AFFECTS whom,
        const std::string& special);
 
    /** special_distant_filtering_impl : return an boolean value if special matche with filter
     * @return True if the @a special is active.
     * @param self_attack the attack used by unit who fight.
     * @param other_attack the attack used by opponent.
     * @param self the unit who fight.
     * @param self_loc location of @a self.
     * @param whom determine if unit affected or not by special ability.
     * @param filter if special check with filter, return true.
     * @param sub_filter if true, check the attributes of [filter_special], else, check special(_id/type)(_active).
     * @param leader_bool If true, [leadership] abilities are checked.
     */
    static bool special_distant_filtering_impl(
        const const_attack_ptr& self_attack,
        const unit_const_ptr& self,
        const map_location& self_loc,
        const const_attack_ptr& other_attack,
        AFFECTS whom,
        const config & filter,
        bool sub_filter,
        bool leader_bool=false);
 
    // Used via specials_context() to control which specials are
    // considered active.
    friend class specials_context_t;
    mutable map_location self_loc_, other_loc_;
    mutable unit_const_ptr self_;
    mutable unit_const_ptr other_;
    mutable bool is_attacker_;
    mutable const_attack_ptr other_attack_;
    mutable bool is_for_listing_ = false;
public:
    class specials_context_t {
        std::shared_ptr<const attack_type> parent;
        friend class attack_type;
        /** Initialize weapon specials context for listing */
        explicit specials_context_t(const attack_type& weapon, bool attacking);
        /** Initialize weapon specials context for a unit type */
        specials_context_t(const attack_type& weapon, const unit_type& self_type, const map_location& loc, bool attacking = true);
        /** Initialize weapon specials context for a single unit */
        specials_context_t(const attack_type& weapon, const_attack_ptr other_weapon,
            unit_const_ptr self, unit_const_ptr other,
            const map_location& self_loc, const map_location& other_loc,
            bool attacking);
        /** Initialize weapon specials context for a pair of units */
        specials_context_t(const attack_type& weapon, unit_const_ptr self, const map_location& loc, bool attacking);
        specials_context_t(const specials_context_t&) = delete;
        bool was_moved = false;
    public:
        // Destructor at least needs to be public for all this to work.
        ~specials_context_t();
        specials_context_t(specials_context_t&&);
    };
    // Set up a specials context.
    // Usage: auto ctx = weapon.specials_context(...);
    specials_context_t specials_context(unit_const_ptr self, unit_const_ptr other,
        const map_location& unit_loc, const map_location& other_loc,
        bool attacking, const_attack_ptr other_attack) const {
        return specials_context_t(*this, other_attack, self, other, unit_loc, other_loc, attacking);
    }
    specials_context_t specials_context(unit_const_ptr self, const map_location& loc, bool attacking = true) const {
        return specials_context_t(*this, self, loc, attacking);
    }
    specials_context_t specials_context(const unit_type& self_type, const map_location& loc, bool attacking = true) const {
        return specials_context_t(*this, self_type, loc, attacking);
    }
    specials_context_t specials_context_for_listing(bool attacking = true) const {
        return specials_context_t(*this, attacking);
    }
    void set_changed(bool value)
    {
        changed_ = value;
    }
    bool get_changed() const
    {
        return changed_;
    }
private:
 
    t_string description_;
    std::string id_;
    std::string type_;
    std::string icon_;
    std::string range_;
    int min_range_, max_range_;
    utils::optional<unit_alignments::type> alignment_;
    int damage_;
    int num_attacks_;
    double attack_weight_;
    double defense_weight_;
 
    int accuracy_;
    int movement_used_;
    int attacks_used_;
    int parry_;
    config specials_;
    bool changed_;
    /**
     * While processing a recursive match, all the filters that are currently being checked, oldest first.
     * Each will have an instance of recursion_guard that is currently allocated permission to recurse, and
     * which will pop the config off this stack when the recursion_guard is finalized.
     */
    mutable std::vector<const config*> open_queries_;
};
 
using attack_list = std::vector<attack_ptr>;
using attack_itors = boost::iterator_range<boost::indirect_iterator<attack_list::iterator>>;
using const_attack_itors = boost::iterator_range<boost::indirect_iterator<attack_list::const_iterator>>;
 
inline attack_itors make_attack_itors(attack_list& atks) {
    return boost::make_iterator_range(boost::make_indirect_iterator(atks.begin()), boost::make_indirect_iterator(atks.end()));
}
 
inline const_attack_itors make_attack_itors(const attack_list& atks) {
    return boost::make_iterator_range(boost::make_indirect_iterator(atks.begin()), boost::make_indirect_iterator(atks.end()));
}