updates?

models/src/bundle/armour.rs

@@ -0,0 +1,200 @@
+use bevy_ecs::{component::Component, entity::Entity};
+use rand::distr::Distribution;
+use strum::Display;
+
+use crate::{bundle::player::BodyPart, dto::armour::CoverageDto};
+
+#[derive(Clone, Copy, Debug, Display, Component)]
+#[cfg_attr(feature = "json", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "json", serde(rename_all = "snake_case"))]
+pub enum Immunity {
+    Radiation,
+    NerveGas,
+    TearGas,
+    PepperSpray,
+    FlashGrenade,
+    ConcussionGrenade,
+    Insanity,
+}
+
+#[derive(Component, Default)]
+pub struct Immunities(pub Vec<Immunity>);
+
+#[derive(Component, Default)]
+pub struct Armour;
+
+#[derive(Component, Default)]
+pub struct ArmourCoverage(pub ArmourVec<f32>);
+
+impl From<CoverageDto> for ArmourCoverage {
+    fn from(value: CoverageDto) -> Self {
+        let mut result = Self::default();
+
+        result.0[ArmourBodyPartSlot::Heart] = value.heart;
+        result.0[ArmourBodyPartSlot::Stomach] = value.stomach;
+        result.0[ArmourBodyPartSlot::Chest] = value.chest;
+        result.0[ArmourBodyPartSlot::Arms] = value.arm;
+        result.0[ArmourBodyPartSlot::Groin] = value.groin;
+        result.0[ArmourBodyPartSlot::Legs] = value.leg;
+        result.0[ArmourBodyPartSlot::Throat] = value.throat;
+        result.0[ArmourBodyPartSlot::Hands] = value.hand;
+        result.0[ArmourBodyPartSlot::Feet] = value.foot;
+        result.0[ArmourBodyPartSlot::Head] = value.head;
+
+        result
+    }
+}
+
+#[derive(Component, Default)]
+pub struct ArmourValue(pub f32);
+
+enum ArmourIterState {
+    Head,
+    Body,
+    Legs,
+    Feet,
+    Hands,
+}
+
+#[derive(Debug, Clone, Component)]
+pub struct PlayerArmour {
+    pub head: Option<Entity>,
+    pub torso: Option<Entity>,
+    pub legs: Option<Entity>,
+    pub feet: Option<Entity>,
+    pub hands: Option<Entity>,
+}
+
+#[derive(Debug)]
+pub struct BodyPartCoverage {
+    pub armour: Entity,
+    pub coverage: f32,
+    pub armour_value: f32,
+}
+
+#[derive(Component, Default, Debug)]
+pub struct ArmourBodyPart {
+    pub armour_pieces: Vec<BodyPartCoverage>,
+}
+
+#[derive(Component, Debug)]
+pub struct ArmourBodyParts(pub ArmourVec<Entity>);
+
+pub struct ArmourIter<'a> {
+    state: Option<ArmourIterState>,
+    equipped_armour: &'a PlayerArmour,
+}
+
+impl<'a> Iterator for ArmourIter<'a> {
+    type Item = Entity;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        loop {
+            let (next, piece) = match self.state {
+                None => (ArmourIterState::Head, self.equipped_armour.head),
+                Some(ArmourIterState::Head) => (ArmourIterState::Body, self.equipped_armour.torso),
+                Some(ArmourIterState::Body) => (ArmourIterState::Legs, self.equipped_armour.legs),
+                Some(ArmourIterState::Legs) => (ArmourIterState::Feet, self.equipped_armour.feet),
+                Some(ArmourIterState::Feet) => (ArmourIterState::Hands, self.equipped_armour.hands),
+                Some(ArmourIterState::Hands) => return None,
+            };
+
+            self.state = Some(next);
+            if piece.is_some() {
+                return piece;
+            }
+        }
+    }
+}
+
+impl<'a> IntoIterator for &'a PlayerArmour {
+    type Item = Entity;
+
+    type IntoIter = ArmourIter<'a>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        ArmourIter {
+            state: None,
+            equipped_armour: self,
+        }
+    }
+}
+
+#[repr(usize)]
+#[derive(Clone, Copy, strum::EnumIter)]
+pub enum ArmourBodyPartSlot {
+    Arms,
+    Stomach,
+    Heart,
+    Chest,
+    Throat,
+    Hands,
+    Groin,
+    Legs,
+    Head,
+    Feet,
+}
+
+impl From<BodyPart> for ArmourBodyPartSlot {
+    fn from(value: BodyPart) -> Self {
+        match value {
+            BodyPart::LeftArm | BodyPart::RightArm => Self::Arms,
+            BodyPart::Stomach => Self::Stomach,
+            BodyPart::Heart => Self::Heart,
+            BodyPart::Chest => Self::Chest,
+            BodyPart::Throat => Self::Throat,
+            BodyPart::LeftHand | BodyPart::RightHand => Self::Hands,
+            BodyPart::Groin => Self::Groin,
+            BodyPart::LeftLeg | BodyPart::RightLeg => Self::Legs,
+            BodyPart::Head => Self::Head,
+            BodyPart::LeftFoot | BodyPart::RightFoot => Self::Feet,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, Default)]
+pub struct ArmourVec<T>(pub [T; 10]);
+
+impl<T> std::ops::Index<ArmourBodyPartSlot> for ArmourVec<T> {
+    type Output = T;
+
+    fn index(&self, index: ArmourBodyPartSlot) -> &Self::Output {
+        &self.0[index as usize]
+    }
+}
+
+impl<T> std::ops::IndexMut<ArmourBodyPartSlot> for ArmourVec<T> {
+    fn index_mut(&mut self, index: ArmourBodyPartSlot) -> &mut Self::Output {
+        &mut self.0[index as usize]
+    }
+}
+
+impl<T> IntoIterator for ArmourVec<T> {
+    type Item = T;
+
+    type IntoIter = std::array::IntoIter<T, 10>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.0.into_iter()
+    }
+}
+
+impl<'a> Distribution<Option<&'a BodyPartCoverage>> for &'a ArmourBodyPart {
+    fn sample<R: rand::prelude::Rng + ?Sized>(&self, rng: &mut R) -> Option<&'a BodyPartCoverage> {
+        let mut current = None;
+        for piece in &self.armour_pieces {
+            // NOTE: This is not strictly speaking correct, but the edge cases where this applies
+            // should be very rare, and it should be a decent enough heuristic to barely make a
+            // difference from the actual pixel comparisons that torn seems to be using for this.
+            if current
+                .map(|c: &BodyPartCoverage| c.armour_value)
+                .unwrap_or_default()
+                < piece.armour_value
+                && rng.random_bool(piece.coverage as f64)
+            {
+                current = Some(piece);
+            }
+        }
+        current
+    }
+}

models/src/bundle/bonus.rs

@@ -0,0 +1,199 @@
+use bevy_ecs::{bundle::Bundle, component::Component};
+use strum::Display;
+
+use crate::bundle::player::BodyPart;
+
+#[derive(Component, Debug, Clone, Copy)]
+#[cfg_attr(feature = "json", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "json", serde(rename_all = "snake_case"))]
+pub enum WeaponBonusType {
+    // Weapon passives
+    Berserk,
+    Conserve,
+    Expose,
+    Grace,
+    Powerful,
+    Specialist,
+
+    // Turn triggered passives
+    Empower,
+    Quicken,
+
+    // First turn effects
+    Assassinate,
+
+    // Additive status effects triggered by damaging hits
+    Cripple,
+    Demoralise,
+    Freeze,
+    Motivate,
+    Slow,
+    Toxin,
+    Weaken,
+    Wither,
+
+    // DOT status effects
+    Bleed,
+    Burning,
+    Lacerate,
+    Poison,
+    SevereBurning,
+
+    // Other status effects
+    Eviscerate,
+    Paralyse,
+    Schock,
+    Stun,
+
+    // Multi attack bonuses
+    Blindfire,
+    Fury,
+    DoubleTap,
+    Rage,
+
+    // Body part multipliers
+    Achilles,
+    Crusher,
+    Cupid,
+    Deadeye,
+    Roshambo,
+    Throttle,
+
+    // Attack nullification types
+    Homerun,
+    Parry,
+}
+
+#[derive(Component)]
+pub struct BonusValue(pub f32);
+
+#[derive(Bundle)]
+pub struct WeaponBonusBundle {
+    pub bonus: WeaponBonusType,
+    pub value: BonusValue,
+}
+
+impl WeaponBonusBundle {
+    pub fn new(bonus: WeaponBonusType, value: f32) -> Self {
+        Self {
+            bonus,
+            value: BonusValue(value),
+        }
+    }
+}
+
+#[derive(Clone, Copy)]
+pub enum TurnTriggeredBonus {
+    Empower,
+    Quicken,
+}
+
+#[derive(Clone, Copy)]
+pub enum FirstTurnBonus {
+    Assassinate,
+}
+
+#[derive(Clone, Copy)]
+pub enum MultiTurnBonus {
+    Blindfire,
+    Fury,
+    DoubleTap,
+    Rage,
+}
+
+impl MultiTurnBonus {
+    #[inline(always)]
+    pub fn counter_label(self) -> &'static str {
+        match self {
+            Self::Blindfire => "proc_blindfire",
+            Self::Fury => "proc_fury",
+            Self::DoubleTap => "proc_double_tap",
+            Self::Rage => "proc_rage",
+        }
+    }
+}
+
+#[derive(Clone, Copy)]
+pub enum OpponentStatusEffect {
+    Cripple,
+    // TODO: implement for group fights
+    Demoralise,
+    Freeze,
+    Slow,
+    Toxin,
+    Weaken,
+    Wither,
+}
+
+#[derive(Clone, Copy)]
+pub enum SelfStatusEffect {
+    Motivate,
+}
+
+#[derive(Clone, Copy)]
+pub enum BonusPartDamageBonus {
+    Achilles,
+    Crusher,
+    Cupid,
+    Deadeye,
+    Roshambo,
+    Throttle,
+}
+
+impl BonusPartDamageBonus {
+    pub fn dmg_bonus(self, part: BodyPart, value: f32) -> Option<f32> {
+        match self {
+            Self::Achilles => match part {
+                BodyPart::LeftFoot | BodyPart::RightFoot => Some(value),
+                _ => None,
+            },
+            Self::Crusher => {
+                if part == BodyPart::Head {
+                    Some(value)
+                } else {
+                    None
+                }
+            }
+            Self::Cupid => {
+                if part == BodyPart::Heart {
+                    Some(value)
+                } else {
+                    None
+                }
+            }
+            Self::Deadeye => match part {
+                BodyPart::Head | BodyPart::Heart | BodyPart::Throat => Some(value),
+                _ => None,
+            },
+            Self::Roshambo => {
+                if part == BodyPart::Groin {
+                    Some(value)
+                } else {
+                    None
+                }
+            }
+            Self::Throttle => {
+                if part == BodyPart::Throat {
+                    Some(value)
+                } else {
+                    None
+                }
+            }
+        }
+    }
+}
+
+#[derive(Clone, Copy, Debug, Display)]
+#[cfg_attr(feature = "json", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "json", serde(rename_all = "snake_case"))]
+pub enum ArmourBonusType {
+    Impregnable,
+    Impenetrable,
+    Insurmountable,
+    Invulnerable,
+    Imperviable,
+    Immmutable,
+    Irrepressible,
+    Kinetokinesis,
+    Impassable,
+}

models/src/bundle/mod.rs

@@ -0,0 +1,14 @@
+use bevy_ecs::component::Component;
+
+pub mod armour;
+pub mod bonus;
+pub mod passive;
+pub mod player;
+pub mod stat;
+pub mod weapon;
+
+#[derive(Component, Debug, Default)]
+pub struct Name(pub String);
+
+#[derive(Component, Debug, Default, Clone, Copy)]
+pub struct Id(pub usize);

models/src/bundle/passive.rs

@@ -0,0 +1,207 @@
+use bevy_ecs::{bundle::Bundle, component::Component};
+
+use crate::bundle::player::BodyPart;
+
+#[derive(Component, Default)]
+#[cfg_attr(feature = "json", derive(serde::Deserialize))]
+pub struct Merits {
+    pub life: u16,
+    pub crits: u16,
+
+    pub brawn: u16,
+    pub protection: u16,
+    pub sharpness: u16,
+    pub evasion: u16,
+
+    pub heavy_artillery_mastery: u16,
+    pub machine_gun_mastery: u16,
+    pub rifle_mastery: u16,
+    pub smg_mastery: u16,
+    pub shotgun_mastery: u16,
+    pub pistol_mastery: u16,
+    pub club_mastery: u16,
+    pub piercing_mastery: u16,
+    pub slashing_mastery: u16,
+    pub mechanical_mastery: u16,
+    pub temporary_mastery: u16,
+}
+
+#[derive(Component)]
+#[cfg_attr(feature = "json", derive(serde::Deserialize))]
+pub struct Education {
+    /// Gain a 1% damage bonus to all weapons
+    pub bio2350: bool,
+    /// Gain a 10% damage increase when hitting an opponent's throat
+    pub bio2380: bool,
+    /// Gain a 3% chance increase of achieving a critical hit
+    pub bio2410: bool,
+
+    /// Gain a 1% passive bonus to speed
+    pub cbt2790: bool,
+    /// Gain a +1.00 accuracy increase with Machine Guns
+    pub cbt2820: bool,
+    /// Gain a +1.00 accuracy increase with Submachine guns
+    pub cbt2830: bool,
+    /// Gain a +1.00 accuracy increase with Pistols
+    pub cbt2840: bool,
+    /// Gain a +1.00 accuracy increase with Rifles
+    pub cbt2850: bool,
+    /// Gain a +1.00 accuracy increase with Heavy Artillery
+    pub cbt2860: bool,
+    /// Gain a +1.00 accuracy increase with Shotguns
+    pub cbt2125: bool,
+
+    /// Gain a +1.00 accuracy increase with Temporary weapons
+    pub gen2116: bool,
+    /// Gain a 5% damage increase with Temporary weapons
+    pub gen2119: bool,
+
+    /// Gain a 1% passive bonus to dexterity
+    pub haf2104: bool,
+    /// Gain a 1% passive bonus to speed
+    pub haf2105: bool,
+    /// Gain a 1% passive bonus to strength
+    pub haf2106: bool,
+    /// Gain a 2% passive bonus to strength
+    pub haf2107: bool,
+    /// Gain a 1% passive bonus to dexterity
+    pub haf2108: bool,
+    /// Gain a 3% passive bonus to speed
+    pub haf2109: bool,
+
+    /// Gain a 10% damage increase with Japanese blade weapons
+    pub his2160: bool,
+    /// Gain a 2% bonus to all melee damage
+    pub his2170: bool,
+
+    /// Gain a 1% passive bonus to speed
+    pub mth2240: bool,
+    /// Gain a 1% passive bonus to speed
+    pub mth2250: bool,
+    /// Gain a 1% passive bonus to defense
+    pub mth2260: bool,
+    /// Gain a 2% passive bonus to defense
+    pub mth2320: bool,
+
+    /// Gain a 5% bonus to ammo conservation
+    pub mth2310: bool,
+    /// Gain a 20% bonus to ammo conservation
+    pub mth3330: bool,
+
+    /// Gain a 1% passive bonus to dexterity
+    pub psy2640: bool,
+    /// Gain a 2% passive bonus to dexterity
+    pub psy2650: bool,
+    /// Gain a 4% passive bonus to dexterity
+    pub psy2660: bool,
+    /// Gain an 8% passive bonus to dexterity
+    pub psy2670: bool,
+
+    /// Gain a 1% passive bonus to defense
+    pub def2710: bool,
+    /// Gain a 2% passive bonus to defense
+    pub def2730: bool,
+    /// Gain a 3% passive bonus to defense
+    pub def2740: bool,
+    /// Gain a 2% passive bonus to speed
+    pub def2750: bool,
+    /// Gain a 3% passive bonus to speed
+    pub def2760: bool,
+    /// Gain a 100% increase in damage dealt when using fists alone
+    pub def3770: bool,
+
+    /// Gain a 10% increase in steroid effectiveness
+    // NOTE: this effect is additive with the strip club perks
+    pub spt2480: bool,
+    /// Gain a 2% passive bonus to speed and strength
+    pub spt2490: bool,
+    /// Gain a 2% passive bonus to defense and dexterity
+    pub spt2500: bool,
+}
+
+impl Default for Education {
+    fn default() -> Self {
+        Self {
+            bio2350: true,
+            bio2380: true,
+            bio2410: true,
+            cbt2790: true,
+            cbt2820: true,
+            cbt2830: true,
+            cbt2840: true,
+            cbt2850: true,
+            cbt2860: true,
+            cbt2125: true,
+            gen2116: true,
+            gen2119: true,
+            haf2104: true,
+            haf2105: true,
+            haf2106: true,
+            haf2107: true,
+            haf2108: true,
+            haf2109: true,
+            his2160: true,
+            his2170: true,
+            mth2240: true,
+            mth2250: true,
+            mth2260: true,
+            mth2320: true,
+            mth2310: true,
+            mth3330: true,
+            psy2640: true,
+            psy2650: true,
+            psy2660: true,
+            psy2670: true,
+            def2710: true,
+            def2730: true,
+            def2740: true,
+            def2750: true,
+            def2760: true,
+            def3770: true,
+            spt2480: true,
+            spt2490: true,
+            spt2500: true,
+        }
+    }
+}
+
+#[derive(Component, Default)]
+#[cfg_attr(feature = "json", derive(serde::Deserialize))]
+pub struct FactionUpgrades {
+    pub str: u16,
+    pub spd: u16,
+    pub def: u16,
+    pub dex: u16,
+    pub life: u16,
+    pub acc: u16,
+    pub dmg: u16,
+    pub side_effects: u16,
+}
+
+#[derive(Component)]
+#[cfg_attr(feature = "json", derive(serde::Deserialize))]
+pub enum DrugCooldown {
+    Xanax,
+    Vicodin,
+}
+
+#[derive(Clone, Copy)]
+pub enum EducationPartDamageBonus {
+    Bio2380,
+}
+
+impl EducationPartDamageBonus {
+    pub fn dmg_bonus(self, part: BodyPart) -> Option<f32> {
+        match part {
+            BodyPart::Throat => Some(0.10),
+            _ => None,
+        }
+    }
+}
+
+#[derive(Bundle, Default)]
+pub(crate) struct PassiveBundle {
+    pub merits: Merits,
+    pub education: Education,
+    pub faction: FactionUpgrades,
+}

models/src/bundle/player.rs

@@ -0,0 +1,184 @@
+use bevy_ecs::{bundle::Bundle, component::Component, entity::Entity, message::Message};
+use strum::Display;
+
+use crate::bundle::{
+    Name,
+    bonus::BonusPartDamageBonus,
+    passive::EducationPartDamageBonus,
+    stat::{CritRate, DamageBonus, SimpleStatBundle, WeaponAccuracy},
+    weapon::WeaponSlot,
+};
+
+#[derive(Component)]
+pub struct Attacker;
+
+#[derive(Component)]
+pub struct Defender;
+
+#[derive(Component)]
+pub struct Defeated;
+
+#[derive(Component)]
+pub struct Current;
+
+#[derive(Component)]
+pub struct CurrentTarget;
+
+#[derive(Component, Default)]
+pub struct Player;
+
+#[derive(Component)]
+pub struct Level(pub u16);
+
+impl Default for Level {
+    fn default() -> Self {
+        Self(1)
+    }
+}
+
+#[derive(Component, Debug)]
+pub struct MaxHealth(pub u16);
+
+impl Default for MaxHealth {
+    fn default() -> Self {
+        Self(100)
+    }
+}
+
+#[derive(Component, Debug, Default)]
+pub struct CombatTurns(pub u16);
+
+#[derive(Component, Debug)]
+pub struct Weapons {
+    pub primary: Option<Entity>,
+    pub secondary: Option<Entity>,
+    pub melee: Option<Entity>,
+    pub temporary: Option<Entity>,
+    pub fists: Entity,
+    pub kick: Entity,
+}
+
+#[derive(Component, Debug)]
+#[cfg_attr(feature = "json", derive(serde::Deserialize))]
+#[cfg_attr(feature = "json", serde(tag = "type", rename_all = "snake_case"))]
+pub enum PlayerStrategy {
+    AlwaysFists,
+    AlwaysKicks,
+    PrimaryMelee {
+        reload: bool,
+    },
+    InOrder {
+        order: Vec<WeaponSlot>,
+        reload: bool,
+    },
+}
+
+impl Default for PlayerStrategy {
+    fn default() -> Self {
+        Self::AlwaysFists
+    }
+}
+
+#[derive(Message)]
+pub struct ChooseWeapon(pub Entity);
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum BodyPart {
+    LeftHand,
+    RightHand,
+    LeftArm,
+    RightArm,
+    LeftFoot,
+    RightFoot,
+    LeftLeg,
+    RightLeg,
+    Stomach,
+    Chest,
+    Groin,
+    Head,
+    Throat,
+    Heart,
+}
+
+impl std::fmt::Display for BodyPart {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Self::LeftHand => write!(f, "Left hand"),
+            Self::RightHand => write!(f, "Right hand"),
+            Self::LeftArm => write!(f, "Left arm"),
+            Self::RightArm => write!(f, "Right arm"),
+            Self::LeftFoot => write!(f, "Left foot"),
+            Self::RightFoot => write!(f, "Right foot"),
+            Self::LeftLeg => write!(f, "Left leg"),
+            Self::RightLeg => write!(f, "Right leg"),
+            Self::Stomach => write!(f, "Stomach"),
+            Self::Chest => write!(f, "Chest"),
+            Self::Groin => write!(f, "Groin"),
+            Self::Head => write!(f, "Head"),
+            Self::Throat => write!(f, "Throat"),
+            Self::Heart => write!(f, "Heart"),
+        }
+    }
+}
+
+#[derive(Clone, Copy, PartialEq, Eq, Display)]
+pub enum FightEndType {
+    Victory,
+    Stalemate,
+    Loss,
+}
+
+#[derive(Component)]
+pub enum PartDamageBonus {
+    Education(EducationPartDamageBonus),
+    WeaponBonus {
+        value: f32,
+        bonus: BonusPartDamageBonus,
+    },
+}
+
+#[derive(Message)]
+pub enum HealthRestore {
+    Cauterise,
+    Serotonin { extra_effectiveness: f32 },
+    Bloodlust { dmg: u32, value: f32 },
+}
+
+impl PartDamageBonus {
+    pub fn dmg_bonus(&self, part: BodyPart) -> Option<f32> {
+        match self {
+            Self::Education(edu) => edu.dmg_bonus(part),
+            Self::WeaponBonus { value, bonus } => bonus.dmg_bonus(part, *value),
+        }
+    }
+}
+
+#[derive(Bundle)]
+pub struct PlayerBundle {
+    pub name: Name,
+    pub player: Player,
+    pub level: Level,
+    pub crit_rate: SimpleStatBundle<CritRate>,
+    // TODO: since these two need to be tracked here anyways it might be preferable to shift all
+    // player specific passives here instead of tracking them on the weapons
+    pub acc_bonus: SimpleStatBundle<WeaponAccuracy>,
+    pub dmg_bonus: SimpleStatBundle<DamageBonus>,
+
+    pub strategy: PlayerStrategy,
+    pub combat_turns: CombatTurns,
+}
+
+impl PlayerBundle {
+    pub fn new(name: impl ToString, level: u16, strategy: PlayerStrategy) -> Self {
+        Self {
+            name: Name(name.to_string()),
+            player: Player,
+            level: Level(level),
+            crit_rate: SimpleStatBundle::new(24),
+            acc_bonus: SimpleStatBundle::new(0.0),
+            dmg_bonus: SimpleStatBundle::new(0.0),
+            strategy,
+            combat_turns: Default::default(),
+        }
+    }
+}

models/src/bundle/stat.rs

@@ -0,0 +1,408 @@
+use std::marker::PhantomData;
+
+use bevy_ecs::{bundle::Bundle, component::Component};
+
+use crate::bundle::player::BodyPart;
+
+pub trait SimpleStatMarker: Send + Sync + 'static {
+    type ValueType: Send + Sync + Copy + std::fmt::Display + 'static;
+    type BonusType: Send + Sync + Copy + 'static;
+
+    fn apply_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType;
+    fn revert_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType;
+    fn denormalise_value(value: Self::ValueType) -> Self::ValueType {
+        value
+    }
+    fn denormalise_bonus(value: Self::BonusType) -> Self::BonusType {
+        value
+    }
+}
+
+#[derive(Component)]
+pub struct SimpleStatBaseline<Stat: SimpleStatMarker> {
+    pub value: Stat::ValueType,
+    marker: PhantomData<Stat>,
+}
+
+#[derive(Component)]
+pub struct SimpleStatEffective<Stat: SimpleStatMarker> {
+    pub value: Stat::ValueType,
+    marker: PhantomData<Stat>,
+}
+
+#[derive(Component)]
+pub struct SimpleStatBonus<Stat: SimpleStatMarker> {
+    pub label: &'static str,
+    pub value: Stat::BonusType,
+    marker: PhantomData<Stat>,
+}
+
+impl<Stat: SimpleStatMarker> SimpleStatBonus<Stat> {
+    pub fn new(label: &'static str, value: Stat::BonusType) -> Self {
+        Self {
+            label,
+            value,
+            marker: PhantomData,
+        }
+    }
+}
+
+#[derive(Component)]
+pub struct SimpleStatSnapshot<Stat: SimpleStatMarker> {
+    pub value: Stat::ValueType,
+    pub marker: PhantomData<Stat>,
+}
+
+#[derive(Bundle)]
+pub struct SimpleStatBundle<Stat: SimpleStatMarker> {
+    pub baseline: SimpleStatBaseline<Stat>,
+    pub effective: SimpleStatEffective<Stat>,
+}
+
+impl<Stat: SimpleStatMarker> SimpleStatBundle<Stat> {
+    pub fn new(value: Stat::ValueType) -> Self {
+        Self {
+            baseline: SimpleStatBaseline {
+                value,
+                marker: PhantomData,
+            },
+            effective: SimpleStatEffective {
+                value,
+                marker: PhantomData,
+            },
+        }
+    }
+}
+
+impl<Stat: SimpleStatMarker> Clone for SimpleStatEffective<Stat> {
+    fn clone(&self) -> Self {
+        *self
+    }
+}
+
+impl<Stat: SimpleStatMarker> Copy for SimpleStatEffective<Stat> where Stat::ValueType: Copy {}
+
+#[derive(Default)]
+pub struct CritRate;
+
+impl SimpleStatMarker for CritRate {
+    type ValueType = u16;
+    type BonusType = u16;
+    fn apply_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        value + bonus
+    }
+    fn revert_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        value - bonus
+    }
+}
+
+impl rand::distr::Distribution<BodyPart> for SimpleStatEffective<CritRate> {
+    fn sample<R: rand::prelude::Rng + ?Sized>(&self, rng: &mut R) -> BodyPart {
+        if rng.random_ratio((self.value) as u32, 200) {
+            match rng.random_range(1..=10) {
+                1 => BodyPart::Heart,
+                2 => BodyPart::Throat,
+                _ => BodyPart::Heart,
+            }
+        } else {
+            match rng.random_range(1..=20) {
+                1 => BodyPart::LeftHand,
+                2 => BodyPart::RightHand,
+                3 => BodyPart::LeftArm,
+                4 => BodyPart::RightArm,
+                5 => BodyPart::LeftFoot,
+                6 => BodyPart::RightFoot,
+                7 | 8 => BodyPart::RightLeg,
+                9 | 10 => BodyPart::LeftLeg,
+                11..=15 => BodyPart::Chest,
+                16 => BodyPart::Groin,
+                _ => BodyPart::Stomach,
+            }
+        }
+    }
+}
+
+impl<Stat> std::ops::Add<&SimpleStatEffective<Stat>> for &SimpleStatEffective<Stat>
+where
+    Stat: SimpleStatMarker,
+    Stat::ValueType: std::ops::Add<Stat::ValueType, Output = Stat::ValueType>,
+{
+    type Output = SimpleStatEffective<Stat>;
+
+    fn add(self, rhs: &SimpleStatEffective<Stat>) -> Self::Output {
+        SimpleStatEffective {
+            value: self.value + rhs.value,
+            marker: PhantomData,
+        }
+    }
+}
+
+#[derive(Default)]
+pub struct AmmoControl;
+
+impl SimpleStatMarker for AmmoControl {
+    type ValueType = f32;
+    type BonusType = f32;
+    fn apply_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        value + bonus
+    }
+    fn revert_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        value - bonus
+    }
+    fn denormalise_value(value: Self::ValueType) -> Self::ValueType {
+        value * 100.0
+    }
+    fn denormalise_bonus(value: Self::BonusType) -> Self::BonusType {
+        value * 100.0
+    }
+}
+
+#[derive(Default)]
+pub struct DamageBonus;
+
+impl SimpleStatMarker for DamageBonus {
+    type ValueType = f32;
+    type BonusType = f32;
+    fn apply_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        value + bonus
+    }
+    fn revert_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        value - bonus
+    }
+    fn denormalise_value(value: Self::ValueType) -> Self::ValueType {
+        value * 100.0
+    }
+    fn denormalise_bonus(value: Self::BonusType) -> Self::BonusType {
+        value * 100.0
+    }
+}
+
+#[derive(Default)]
+pub struct WeaponAccuracy;
+
+impl SimpleStatMarker for WeaponAccuracy {
+    type ValueType = f32;
+    type BonusType = f32;
+    fn apply_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        value + bonus
+    }
+    fn revert_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        value - bonus
+    }
+    fn denormalise_value(value: Self::ValueType) -> Self::ValueType {
+        value * 50.0 + 50.0
+    }
+    fn denormalise_bonus(value: Self::BonusType) -> Self::BonusType {
+        value * 50.0
+    }
+}
+
+#[derive(Default)]
+pub struct ClipSize;
+
+impl SimpleStatMarker for ClipSize {
+    type ValueType = u16;
+    type BonusType = f32;
+    fn apply_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        ((value as f32) * bonus).round() as u16
+    }
+    fn revert_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        ((value as f32) / bonus).round() as u16
+    }
+}
+
+#[derive(Default)]
+pub struct Clips;
+
+impl SimpleStatMarker for Clips {
+    type ValueType = u16;
+    type BonusType = i16;
+    fn apply_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        ((value as i16) + bonus) as u16
+    }
+    fn revert_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        ((value as i16) - bonus) as u16
+    }
+}
+
+#[derive(Default)]
+pub struct Health;
+
+impl SimpleStatMarker for Health {
+    type ValueType = u16;
+    type BonusType = u16;
+    fn apply_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        value + bonus
+    }
+    fn revert_bonus(value: Self::ValueType, bonus: Self::BonusType) -> Self::ValueType {
+        value - bonus
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub enum StatType {
+    Str,
+    Def,
+    Spd,
+    Dex,
+}
+
+pub trait StatMarker: Send + Sync + 'static {
+    fn stat_type() -> StatType;
+}
+
+#[derive(Debug, Default)]
+pub struct Strength;
+impl StatMarker for Strength {
+    fn stat_type() -> StatType {
+        StatType::Str
+    }
+}
+
+#[derive(Debug, Default)]
+pub struct Defence;
+impl StatMarker for Defence {
+    fn stat_type() -> StatType {
+        StatType::Def
+    }
+}
+
+#[derive(Debug, Default)]
+pub struct Speed;
+impl StatMarker for Speed {
+    fn stat_type() -> StatType {
+        StatType::Spd
+    }
+}
+
+#[derive(Debug, Default)]
+pub struct Dexterity;
+impl StatMarker for Dexterity {
+    fn stat_type() -> StatType {
+        StatType::Dex
+    }
+}
+
+#[derive(Component)]
+pub struct BaselineStat<Stat: StatMarker> {
+    pub value: f32,
+    pub marker: PhantomData<Stat>,
+}
+
+impl<Stat: StatMarker> Default for BaselineStat<Stat> {
+    fn default() -> Self {
+        Self {
+            value: 10.0,
+            marker: PhantomData,
+        }
+    }
+}
+
+#[derive(Component, Default)]
+pub struct EffectiveStat<Stat: StatMarker> {
+    pub value: f32,
+    pub marker: PhantomData<Stat>,
+}
+
+#[derive(Component)]
+pub struct AdditiveBonuses<Stat: StatMarker> {
+    pub factor: f32,
+    pub marker: PhantomData<Stat>,
+}
+
+impl<Stat: StatMarker> Default for AdditiveBonuses<Stat> {
+    fn default() -> Self {
+        Self {
+            factor: 1.0,
+            marker: PhantomData,
+        }
+    }
+}
+
+#[derive(Component)]
+pub struct MultiplicativeBonuses<Stat: StatMarker> {
+    pub factor: f32,
+    pub marker: PhantomData<Stat>,
+}
+
+impl<Stat: StatMarker> Default for MultiplicativeBonuses<Stat> {
+    fn default() -> Self {
+        Self {
+            factor: 1.0,
+            marker: PhantomData,
+        }
+    }
+}
+
+#[derive(Bundle, Default)]
+pub struct StatBundle<Stat: StatMarker> {
+    pub baseline: BaselineStat<Stat>,
+    pub additive: AdditiveBonuses<Stat>,
+    pub multiplicative: MultiplicativeBonuses<Stat>,
+    pub effective: EffectiveStat<Stat>,
+}
+
+#[derive(Component)]
+pub struct StatSnapshot<Stat: StatMarker> {
+    pub additive_bonuses: f32,
+    pub multiplicative_bonuses: f32,
+    pub effective: f32,
+    pub marker: PhantomData<Stat>,
+}
+
+impl<Stat: StatMarker> StatBundle<Stat> {
+    pub fn new(baseline: f32) -> Self {
+        Self {
+            baseline: BaselineStat {
+                value: baseline,
+                marker: PhantomData,
+            },
+            effective: EffectiveStat {
+                value: baseline,
+                marker: PhantomData,
+            },
+            additive: AdditiveBonuses {
+                factor: 1.0,
+                marker: PhantomData,
+            },
+            multiplicative: MultiplicativeBonuses {
+                factor: 1.0,
+                marker: PhantomData,
+            },
+        }
+    }
+}
+
+#[derive(Component)]
+pub struct AdditiveBonus<Stat: StatMarker> {
+    pub label: &'static str,
+    pub value: f32,
+    marker: PhantomData<Stat>,
+}
+
+impl<Stat: StatMarker> AdditiveBonus<Stat> {
+    pub fn new(label: &'static str, value: f32) -> Self {
+        Self {
+            label,
+            value,
+            marker: PhantomData,
+        }
+    }
+}
+
+#[derive(Component)]
+pub struct MultiplicativeBonus<Stat: StatMarker> {
+    pub label: &'static str,
+    pub value: f32,
+    marker: PhantomData<Stat>,
+}
+
+impl<Stat: StatMarker> MultiplicativeBonus<Stat> {
+    pub fn new(label: &'static str, value: f32) -> Self {
+        Self {
+            label,
+            value,
+            marker: PhantomData,
+        }
+    }
+}

models/src/bundle/weapon.rs

@@ -0,0 +1,230 @@
+use bevy_ecs::{bundle::Bundle, component::Component};
+use strum::Display;
+
+use crate::{
+    bundle::{
+        Name,
+        stat::{
+            AmmoControl, ClipSize, Clips, CritRate, DamageBonus, SimpleStatBundle, WeaponAccuracy,
+        },
+    },
+    dto::weapon::{WeaponAmmo, WeaponDto},
+};
+
+#[derive(Component)]
+pub struct Usable;
+
+#[derive(Component)]
+pub struct Weapon;
+
+#[derive(Component, Debug, Clone, Copy, PartialEq, Eq)]
+#[cfg_attr(feature = "json", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "json", serde(rename_all = "snake_case"))]
+pub enum WeaponSlot {
+    Primary,
+    Secondary,
+    Melee,
+    Temporary,
+    Fists,
+    Kick,
+}
+
+#[derive(Component, Debug, Clone, Copy)]
+pub enum WeaponVerb {
+    Hit,
+    Kicked,
+    Fired,
+    Threw,
+    Exploded,
+}
+
+#[derive(Component, Clone, Copy)]
+#[cfg_attr(feature = "json", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "json", serde(rename_all = "snake_case"))]
+pub enum WeaponCategory {
+    HeavyArtillery,
+    MachineGun,
+    Rifle,
+    Smg,
+    Shotgun,
+    Pistol,
+    Clubbing,
+    Piercing,
+    Slashing,
+    Mechanical,
+    Temporary,
+    HandToHand,
+}
+
+#[derive(Component, Debug)]
+pub struct DamageStat(pub f32);
+
+#[derive(Component)]
+pub struct Japanese;
+
+#[derive(Component)]
+pub struct Ammo(pub u16);
+
+#[derive(Component)]
+pub struct RateOfFire(pub [u16; 2]);
+
+#[derive(Component)]
+pub struct NeedsReload;
+
+#[derive(Component, Default)]
+pub struct NonTargeted;
+
+#[derive(Component, Default)]
+pub struct Temporary;
+
+#[derive(Component)]
+pub struct Uses(pub u16);
+
+impl Default for Uses {
+    fn default() -> Self {
+        Self(1)
+    }
+}
+
+#[derive(Clone, Copy)]
+#[cfg_attr(feature = "json", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "json", serde(rename_all = "snake_case"))]
+pub enum WeaponMod {
+    ReflexSight,
+    HolographicSight,
+    AcogSight,
+    ThermalSight,
+    Laser1mw,
+    Laser5mw,
+    Laser30mw,
+    Laser100mw,
+    SmallSuppressor,
+    StandardSuppressor,
+    LargeSuppressor,
+    ExtendedMags,
+    HighCapacityMags,
+    ExtraClip,
+    ExtraClip2,
+    AdjustableTrigger,
+    HairTrigger,
+    Bipod,
+    Tripod,
+    CustomGrip,
+    SkeetChoke,
+    ImprovedChoke,
+    FullChoke,
+    RecoilPad,
+    StandardBrake,
+    HeavyDutyBrake,
+    TacticalBrake,
+    SmallLight,
+    PrecisionLight,
+    TacticalIlluminator,
+}
+
+#[derive(Clone, Copy)]
+pub enum TurnTriggeredMod {
+    Bipod,
+    Tripod,
+    SmallLight,
+    PrecisionLight,
+    TacticalIlluminator,
+}
+
+#[derive(Component, Debug, Clone, Copy, Display)]
+pub enum DebuffingTemp {
+    TearGas,
+    SmokeGrenade,
+    PepperSpray,
+    ConcussionGrenade,
+    FlashGrenade,
+}
+
+#[derive(Component, Debug, Clone, Copy, Display)]
+pub enum BuffingTemp {
+    Serotonin,
+    Tyrosine,
+    Melatonin,
+    Epinephrine,
+}
+
+#[derive(Component)]
+pub struct EquippedMods(pub Vec<WeaponMod>);
+
+#[derive(Component)]
+pub struct Experience(pub f32);
+
+#[derive(Bundle)]
+pub struct WeaponBundle {
+    pub usable: Usable,
+    pub weapon: Weapon,
+    pub name: Name,
+    pub verb: WeaponVerb,
+    pub slot: WeaponSlot,
+}
+
+#[derive(Bundle)]
+pub struct DamagingWeaponBundle {
+    pub crit_rate: SimpleStatBundle<CritRate>,
+    pub dmg: DamageStat,
+    pub acc: SimpleStatBundle<WeaponAccuracy>,
+    pub dmg_bonus: SimpleStatBundle<DamageBonus>,
+    pub equipped_mods: EquippedMods,
+    pub experience: Experience,
+    pub category: WeaponCategory,
+}
+
+#[derive(Bundle)]
+pub struct AmmoWeaponBundle {
+    pub ammo: Ammo,
+    pub clips: SimpleStatBundle<Clips>,
+    pub clip_size: SimpleStatBundle<ClipSize>,
+    pub rate_of_fire: RateOfFire,
+    pub ammo_control: SimpleStatBundle<AmmoControl>,
+}
+
+impl WeaponBundle {
+    pub fn new(name: String, verb: WeaponVerb, slot: WeaponSlot) -> Self {
+        Self {
+            usable: Usable,
+            weapon: Weapon,
+            name: Name(name),
+            verb,
+            slot,
+        }
+    }
+
+    pub fn fists() -> Self {
+        Self::new("Fists".to_owned(), WeaponVerb::Hit, WeaponSlot::Fists)
+    }
+
+    pub fn kick() -> Self {
+        Self::new("Kick".to_owned(), WeaponVerb::Kicked, WeaponSlot::Kick)
+    }
+}
+
+impl AmmoWeaponBundle {
+    pub fn new(weapon_ammo: &WeaponAmmo) -> Self {
+        Self {
+            ammo: Ammo(weapon_ammo.clip_size),
+            clips: SimpleStatBundle::new(2),
+            clip_size: SimpleStatBundle::new(weapon_ammo.clip_size),
+            rate_of_fire: RateOfFire(weapon_ammo.rate_of_fire),
+            ammo_control: SimpleStatBundle::new(0.0),
+        }
+    }
+}
+
+impl DamagingWeaponBundle {
+    pub fn new(dto: &WeaponDto) -> Self {
+        Self {
+            crit_rate: SimpleStatBundle::new(0),
+            dmg: DamageStat(dto.dmg.unwrap_or(dto.base_dmg) / 10.0),
+            acc: SimpleStatBundle::new((dto.acc.unwrap_or(dto.base_acc) - 50.0) / 50.0),
+            dmg_bonus: SimpleStatBundle::new(0.0),
+            equipped_mods: EquippedMods(dto.mods.iter().filter_map(|m| *m).collect()),
+            experience: Experience(dto.experience.unwrap_or_default()),
+            category: dto.cat,
+        }
+    }
+}

models/src/dto/metrics.rs

@@ -0,0 +1,32 @@
+#[cfg_attr(feature = "json", derive(serde::Serialize))]
+#[cfg_attr(feature = "json", serde(tag = "type", rename_all = "snake_case"))]
+#[derive(Debug, Clone)]
+pub enum EntityInfo {
+    Player {
+        name: String,
+        id: usize,
+        is_attacker: bool,
+    },
+    Weapon {
+        name: String,
+        owner: usize,
+        id: usize,
+    },
+    Global,
+}
+
+#[cfg_attr(feature = "json", derive(serde::Serialize))]
+#[derive(Debug)]
+pub struct Counter {
+    pub value: u64,
+    pub entity: EntityInfo,
+    pub label: &'static str,
+}
+
+#[cfg_attr(feature = "json", derive(serde::Serialize))]
+#[derive(Debug)]
+pub struct Histogram {
+    pub values: Vec<u32>,
+    pub entity: EntityInfo,
+    pub label: &'static str,
+}

models/src/dto/mod.rs

@@ -0,0 +1,14 @@
+use std::sync::atomic::{AtomicUsize, Ordering};
+
+use crate::bundle::Id;
+
+pub mod armour;
+pub mod metrics;
+pub mod player;
+pub mod weapon;
+
+static ID_COUNTER: AtomicUsize = AtomicUsize::new(0);
+
+fn draw_id() -> Id {
+    Id(ID_COUNTER.fetch_add(1, Ordering::Relaxed))
+}

models/src/dto/player.rs

@@ -0,0 +1,107 @@
+use bevy_ecs::prelude::*;
+
+use crate::{
+    bundle::{
+        armour::PlayerArmour,
+        passive::{DrugCooldown, Education, FactionUpgrades, Merits, PassiveBundle},
+        player::{PlayerBundle, PlayerStrategy, Weapons},
+        stat::{Defence, Dexterity, Speed, StatBundle, Strength},
+    },
+    dto::{armour::ArmourDto, draw_id, weapon::WeaponDto},
+};
+
+#[cfg_attr(feature = "json", derive(serde::Deserialize))]
+pub struct EquippedWeapons {
+    pub primary: Option<WeaponDto>,
+    pub secondary: Option<WeaponDto>,
+    pub melee: Option<WeaponDto>,
+    pub temporary: Option<WeaponDto>,
+}
+
+#[cfg_attr(feature = "json", derive(serde::Deserialize))]
+#[derive(Default)]
+pub struct EquippedArmour {
+    pub helmet: Option<ArmourDto>,
+    pub body: Option<ArmourDto>,
+    pub pants: Option<ArmourDto>,
+    pub gloves: Option<ArmourDto>,
+    pub boots: Option<ArmourDto>,
+}
+
+#[cfg_attr(feature = "json", derive(serde::Deserialize))]
+pub struct Stats {
+    pub str: f32,
+    pub def: f32,
+    pub spd: f32,
+    pub dex: f32,
+}
+
+#[cfg_attr(feature = "json", derive(serde::Deserialize))]
+pub struct PlayerDto {
+    pub name: String,
+    pub level: u16,
+    pub stats: Stats,
+    pub merits: Option<Merits>,
+    pub education: Option<Education>,
+    pub weapons: EquippedWeapons,
+    pub armour: EquippedArmour,
+    pub faction: Option<FactionUpgrades>,
+    pub drug: Option<DrugCooldown>,
+    pub strategy: PlayerStrategy,
+}
+
+impl PlayerDto {
+    pub fn spawn(self, world: &mut World) -> EntityWorldMut<'_> {
+        let primary = self.weapons.primary.map(|p| p.spawn(world));
+        let secondary = self.weapons.secondary.map(|s| s.spawn(world));
+        let melee = self.weapons.melee.map(|m| m.spawn(world));
+        let temporary = self.weapons.temporary.map(|m| m.spawn(world));
+        let fists = WeaponDto::FISTS.spawn(world);
+        let kick = WeaponDto::KITCHEN_KNIFE.spawn(world);
+
+        let head = self.armour.helmet.map(|a| a.spawn(world));
+        let torso = self.armour.body.map(|a| a.spawn(world));
+        let legs = self.armour.pants.map(|a| a.spawn(world));
+        let hands = self.armour.gloves.map(|a| a.spawn(world));
+        let feet = self.armour.boots.map(|a| a.spawn(world));
+
+        let mut commands = world.spawn(draw_id());
+
+        commands.insert((
+            PlayerBundle::new(self.name, self.level, self.strategy),
+            StatBundle::<Strength>::new(self.stats.str),
+            StatBundle::<Defence>::new(self.stats.def),
+            StatBundle::<Speed>::new(self.stats.spd),
+            StatBundle::<Dexterity>::new(self.stats.dex),
+        ));
+
+        let education = self.education.unwrap_or_default();
+        let merits = self.merits.unwrap_or_default();
+        let faction = self.faction.unwrap_or_default();
+
+        commands.insert(PassiveBundle {
+            education,
+            merits,
+            faction,
+        });
+
+        commands.insert(Weapons {
+            primary,
+            secondary,
+            melee,
+            temporary,
+            kick,
+            fists,
+        });
+
+        commands.insert(PlayerArmour {
+            torso,
+            head,
+            legs,
+            feet,
+            hands,
+        });
+
+        commands
+    }
+}

models/src/hierarchy.rs

@@ -0,0 +1,178 @@
+use bevy_ecs::{
+    prelude::*,
+    system::{Command, EntityCommands},
+};
+
+#[derive(Component, Debug, Clone, Copy)]
+pub struct Parent(Entity);
+
+impl Parent {
+    pub fn get(&self) -> Entity {
+        self.0
+    }
+}
+
+#[derive(Component, Debug, Clone, Default)]
+pub struct Children(Vec<Entity>);
+
+impl Children {
+    pub fn get(&self) -> &[Entity] {
+        &self.0
+    }
+}
+
+struct AddChild {
+    parent: Entity,
+    child: Entity,
+}
+
+impl Command for AddChild {
+    fn apply(self, world: &mut World) {
+        let mut parent = world.entity_mut(self.parent);
+        if let Some(mut children) = parent.get_mut::<Children>() {
+            children.0.push(self.child);
+        } else {
+            parent.insert(Children(vec![self.child]));
+        }
+    }
+}
+
+struct AddChildren {
+    parent: Entity,
+    children: Vec<Entity>,
+}
+
+impl Command for AddChildren {
+    fn apply(mut self, world: &mut World) {
+        let mut parent = world.entity_mut(self.parent);
+        if let Some(mut children) = parent.get_mut::<Children>() {
+            children.0.append(&mut self.children);
+        } else {
+            parent.insert(Children(self.children));
+        }
+    }
+}
+
+struct RemoveChild {
+    parent: Entity,
+    child: Entity,
+}
+
+impl Command for RemoveChild {
+    fn apply(self, world: &mut World) {
+        let mut parent = world.entity_mut(self.parent);
+        let mut children = parent
+            .get_mut::<Children>()
+            .expect("Parent component has no children");
+        children.0.retain(|child| *child != self.child);
+    }
+}
+
+pub trait HierarchyBuilder {
+    fn add_child(&mut self, child: Entity) -> &mut Self;
+
+    fn add_children(&mut self, children: impl AsRef<[Entity]>) -> &mut Self;
+
+    fn remove_child(&mut self, child: Entity) -> &mut Self;
+
+    fn set_parent(&mut self, parent: Entity) -> &mut Self;
+}
+
+impl<'a> HierarchyBuilder for EntityCommands<'a> {
+    fn add_child(&mut self, child: Entity) -> &mut Self {
+        let parent = self.id();
+        self.commands().queue(AddChild { parent, child });
+        self.commands().entity(child).insert(Parent(parent));
+        self
+    }
+
+    fn add_children(&mut self, children: impl AsRef<[Entity]>) -> &mut Self {
+        let children = children.as_ref();
+        let parent = self.id();
+        self.commands().queue(AddChildren {
+            parent,
+            children: children.to_owned(),
+        });
+        self.commands().insert_batch(
+            children
+                .iter()
+                .map(|e| (*e, Parent(parent)))
+                .collect::<Vec<_>>(),
+        );
+        self
+    }
+
+    fn remove_child(&mut self, child: Entity) -> &mut Self {
+        let parent = self.id();
+        self.commands().queue(RemoveChild { parent, child });
+        self.commands().entity(child).remove::<Parent>();
+        self
+    }
+
+    fn set_parent(&mut self, parent: Entity) -> &mut Self {
+        let child = self.id();
+        self.commands().queue(AddChild { parent, child });
+        self.commands().entity(child).insert(Parent(parent));
+        self
+    }
+}
+
+impl<'w> HierarchyBuilder for EntityWorldMut<'w> {
+    fn add_child(&mut self, child: Entity) -> &mut Self {
+        let parent_id = self.id();
+        unsafe {
+            self.world_mut()
+                .entity_mut(child)
+                .insert(Parent(parent_id))
+                .update_location();
+        }
+        if let Some(mut children) = self.get_mut::<Children>() {
+            children.0.push(child);
+            self
+        } else {
+            self.insert(Children(vec![child]))
+        }
+    }
+
+    fn add_children(&mut self, children: impl AsRef<[Entity]>) -> &mut Self {
+        let parent_id = self.id();
+        unsafe {
+            for child in children.as_ref() {
+                self.world_mut()
+                    .entity_mut(*child)
+                    .insert(Parent(parent_id))
+                    .update_location();
+            }
+        }
+        if let Some(mut old_children) = self.get_mut::<Children>() {
+            old_children.0.append(&mut children.as_ref().to_owned());
+            self
+        } else {
+            self.insert(Children(children.as_ref().to_owned()))
+        }
+    }
+
+    fn remove_child(&mut self, child: Entity) -> &mut Self {
+        unsafe {
+            self.world_mut()
+                .entity_mut(child)
+                .remove::<Parent>()
+                .update_location();
+        }
+        if let Some(mut children) = self.get_mut::<Children>() {
+            children.0.retain(|c| *c != child);
+        }
+        self
+    }
+
+    fn set_parent(&mut self, parent: Entity) -> &mut Self {
+        let child_id = self.id();
+        unsafe {
+            self.world_mut()
+                .entity_mut(parent)
+                .add_child(child_id)
+                .update_location()
+        }
+        self
+    }
+}

models/src/lib.rs

@@ -0,0 +1,3 @@
+pub mod bundle;
+pub mod dto;
+// pub mod hierarchy;