/*
 * Author: Glowbal, Ruthberg
 *
 * Handles advanced ballistics for (BulletBase) projectiles. Called from the unified fired EH only for players.
 *
 * Arguments:
 * None. Parameters inherited from EFUNC(common,firedEH)
 *
 * Return Value:
 * None
 *
 * Example:
 * [] call ace_advanced_ballistics_fnc_handleFired
 *
 * Public: No
 */
#include "script_component.hpp"

//IGNORE_PRIVATE_WARNING ["_unit", "_weapon", "_muzzle", "_mode", "_ammo", "_magazine", "_projectile", "_vehicle", "_gunner", "_turret"];
TRACE_10("firedEH:",_unit, _weapon, _muzzle, _mode, _ammo, _magazine, _projectile, _vehicle, _gunner, _turret);

if (!(_ammo isKindOf "BulletBase")) exitWith {};
if (!alive _projectile) exitWith {};
if (_unit distance ACE_player > GVAR(simulationRadius)) exitWith {};
if (underwater _unit) exitWith {};

private _abort = GVAR(disabledInFullAutoMode) && {getNumber(configFile >> "CfgWeapons" >> _weapon >> _mode >> "autoFire") == 1};
if (!local _unit && {!_abort && !GVAR(simulateForEveryone)}) then {
    // The shooter is non local -> abort unless we match an exception rule        
    _abort = !GVAR(simulateForGroupMembers) || {group ACE_player != group _unit};
    if (_abort && GVAR(simulateForSnipers)) then {
        if (currentWeapon _unit == primaryWeapon _unit && count primaryWeaponItems _unit > 2) then {
            private _opticsName = (primaryWeaponItems _unit) select 2;
            private _opticType = getNumber(configFile >> "CfgWeapons" >> _opticsName >> "ItemInfo" >> "opticType");
            _abort = _opticType != 2; // We only abort if the non local shooter is not a sniper
        };
    };
};
//if (!GVAR(vehicleGunnerEnabled) && !(_unit isKindOf "Man")) then { _abort = true; }; // We currently do not have firedEHs on vehicles

// Get Weapon and Ammo Configurations
private _AmmoCacheEntry = uiNamespace getVariable format[QGVAR(%1), _ammo];
if (isNil "_AmmoCacheEntry") then {
     _AmmoCacheEntry = _ammo call FUNC(readAmmoDataFromConfig);
};
private _WeaponCacheEntry = uiNamespace getVariable format[QGVAR(%1), _weapon];
if (isNil "_WeaponCacheEntry") then {
     _WeaponCacheEntry = _weapon call FUNC(readWeaponDataFromConfig);
};

_AmmoCacheEntry params ["_airFriction", "_caliber", "_bulletLength", "_bulletMass", "_transonicStabilityCoef", "_dragModel", "_ballisticCoefficients", "_velocityBoundaries", "_atmosphereModel", "_ammoTempMuzzleVelocityShifts", "_muzzleVelocityTable", "_barrelLengthTable", "_muzzleVelocityVariationSD"];
_WeaponCacheEntry params ["_barrelTwist", "_twistDirection", "_barrelLength"];

private _temperature = nil; // We need the variable in this scope. So we need to init it here.

private _ammoCount = _unit ammo _muzzle;

private _bulletVelocity = velocity _projectile;
private _muzzleVelocity = vectorMagnitude _bulletVelocity;

if (GVAR(barrelLengthInfluenceEnabled)) then {
    _muzzleVelocity = _muzzleVelocity + ([_barrelLength, _muzzleVelocityTable, _barrelLengthTable, _muzzleVelocity] call FUNC(calculateBarrelLengthVelocityShift));
};
if (GVAR(ammoTemperatureEnabled)) then {
    _temperature = ((getPosASL _unit) select 2) call EFUNC(weather,calculateTemperatureAtHeight);
    _muzzleVelocity = _muzzleVelocity + ([_ammoTempMuzzleVelocityShifts, _temperature] call FUNC(calculateAmmoTemperatureVelocityShift));
};
if (GVAR(muzzleVelocityVariationEnabled)) then {
    private _time = round (CBA_missionTime / 2);
    // Generate seed from publicly known values (via Cantor pairing function)
    private _seed = 0.5 * (_time + _ammoCount) * (_time + _ammoCount + 1) + _ammoCount;
    // Generate normally distributed random number (via Box–Muller transform)
    private _z = sqrt(-2.0 * log(0.00000001 max (-_seed random 1))) * cos(_seed random 360);
    
    _muzzleVelocity = _muzzleVelocity * (_z * _muzzleVelocityVariationSD + 1);
};

_bulletVelocity = (vectorNormalized _bulletVelocity) vectorMultiply _muzzleVelocity;
_projectile setVelocity _bulletVelocity;

if (_abort) exitWith {
    if (missionNamespace getVariable [QEGVAR(windDeflection,enabled), false]) then {
        EGVAR(windDeflection,trackedBullets) pushBack [_projectile, getNumber(configFile >> "CfgAmmo" >> _ammo >> "airFriction")];
    };
};

private _bulletTraceVisible = false;
if (GVAR(bulletTraceEnabled) && cameraView == "GUNNER") then {
    if (currentWeapon ACE_player == binocular ACE_player) then {
        _bulletTraceVisible = true;
    } else {
        if (currentWeapon ACE_player == primaryWeapon ACE_player && count primaryWeaponItems ACE_player > 2) then {
            private _opticsName = (primaryWeaponItems ACE_player) select 2;
            private _opticType = getNumber(configFile >> "CfgWeapons" >> _opticsName >> "ItemInfo" >> "opticType");
            _bulletTraceVisible = _opticType == 2;
        };
    };
};

private _stabilityFactor = 1.5;
if (_caliber * _bulletLength * _bulletMass * _barrelTwist > 0) then {
    if (isNil "_temperature") then {
        _temperature = ((getPosASL _unit) select 2) call EFUNC(weather,calculateTemperatureAtHeight);
    };
    private _barometricPressure = ((getPosASL _projectile) select 2) call EFUNC(weather,calculateBarometricPressure);
    _stabilityFactor = [_caliber, _bulletLength, _bulletMass, _barrelTwist, _muzzleVelocity, _temperature, _barometricPressure] call FUNC(calculateStabilityFactor);
};

GVAR(currentbulletID) = (GVAR(currentbulletID) + 1) % 10000;

"ace_advanced_ballistics" callExtension format["new:%1:%2:%3:%4:%5:%6:%7:%8:%9:%10:%11:%12:%13:%14:%15:%16:%17:%18", GVAR(currentbulletID), _ammoCount, _airFriction, _ballisticCoefficients, _velocityBoundaries, _atmosphereModel, _dragModel, _stabilityFactor, _twistDirection, _transonicStabilityCoef, getPosASL _projectile, _bulletVelocity, EGVAR(common,mapLatitude), EGVAR(weather,currentTemperature), EGVAR(common,mapAltitude), EGVAR(weather,currentHumidity), EGVAR(weather,currentOvercast), CBA_missionTime toFixed 6];

GVAR(allBullets) pushBack [_projectile, _caliber, _bulletTraceVisible, GVAR(currentbulletID)];

if (isNil QGVAR(BulletPFH)) then {
    GVAR(BulletPFH) = [FUNC(handleFirePFH), GVAR(simulationInterval), []] call CBA_fnc_addPerFrameHandler;
};