commit 8bba930fbd7aef95b42be0957e4be7b9a038293f
Author: hheik <4469778+hheik@users.noreply.github.com>
Date:   Mon Mar 18 20:46:57 2024 +0200

    Simple site simulation with combat

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ea8c4bf
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/target
diff --git a/Cargo.lock b/Cargo.lock
new file mode 100644
index 0000000..7c7ea60
--- /dev/null
+++ b/Cargo.lock
@@ -0,0 +1,190 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "adventure_sim"
+version = "0.1.0"
+dependencies = [
+ "bincode",
+ "enum_dispatch",
+ "fastrand",
+ "serde",
+ "uuid",
+]
+
+[[package]]
+name = "bincode"
+version = "1.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1f45e9417d87227c7a56d22e471c6206462cba514c7590c09aff4cf6d1ddcad"
+dependencies = [
+ "serde",
+]
+
+[[package]]
+name = "cfg-if"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
+
+[[package]]
+name = "enum_dispatch"
+version = "0.3.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8f33313078bb8d4d05a2733a94ac4c2d8a0df9a2b84424ebf4f33bfc224a890e"
+dependencies = [
+ "once_cell",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "fastrand"
+version = "2.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25cbce373ec4653f1a01a31e8a5e5ec0c622dc27ff9c4e6606eefef5cbbed4a5"
+
+[[package]]
+name = "getrandom"
+version = "0.2.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "190092ea657667030ac6a35e305e62fc4dd69fd98ac98631e5d3a2b1575a12b5"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi",
+]
+
+[[package]]
+name = "libc"
+version = "0.2.153"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c198f91728a82281a64e1f4f9eeb25d82cb32a5de251c6bd1b5154d63a8e7bd"
+
+[[package]]
+name = "once_cell"
+version = "1.19.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3fdb12b2476b595f9358c5161aa467c2438859caa136dec86c26fdd2efe17b92"
+
+[[package]]
+name = "ppv-lite86"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.78"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2422ad645d89c99f8f3e6b88a9fdeca7fabeac836b1002371c4367c8f984aae"
+dependencies = [
+ "unicode-ident",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.35"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "291ec9ab5efd934aaf503a6466c5d5251535d108ee747472c3977cc5acc868ef"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "rand"
+version = "0.8.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
+dependencies = [
+ "libc",
+ "rand_chacha",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
+dependencies = [
+ "ppv-lite86",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
+dependencies = [
+ "getrandom",
+]
+
+[[package]]
+name = "serde"
+version = "1.0.197"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3fb1c873e1b9b056a4dc4c0c198b24c3ffa059243875552b2bd0933b1aee4ce2"
+dependencies = [
+ "serde_derive",
+]
+
+[[package]]
+name = "serde_derive"
+version = "1.0.197"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7eb0b34b42edc17f6b7cac84a52a1c5f0e1bb2227e997ca9011ea3dd34e8610b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "syn"
+version = "2.0.52"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b699d15b36d1f02c3e7c69f8ffef53de37aefae075d8488d4ba1a7788d574a07"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
+[[package]]
+name = "unicode-ident"
+version = "1.0.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
+
+[[package]]
+name = "uuid"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f00cc9702ca12d3c81455259621e676d0f7251cec66a21e98fe2e9a37db93b2a"
+dependencies = [
+ "getrandom",
+ "rand",
+ "serde",
+ "uuid-macro-internal",
+]
+
+[[package]]
+name = "uuid-macro-internal"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7abb14ae1a50dad63eaa768a458ef43d298cd1bd44951677bd10b732a9ba2a2d"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "wasi"
+version = "0.11.0+wasi-snapshot-preview1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..65b9b78
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,13 @@
+[package]
+name = "adventure_sim"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+bincode = "1.3.3"
+enum_dispatch = "0.3.12"
+fastrand = "2.0.1"
+serde = { version = "1.0.197", features = [ "serde_derive" ] }
+uuid = { version = "1.7.0", features = [ "v4", "fast-rng", "macro-diagnostics", "serde" ] }
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..3d8ec24
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,372 @@
+use std::{
+    collections::{HashMap, HashSet},
+    fmt::Display,
+    num::NonZeroUsize,
+    ops::Sub,
+    time::Duration,
+};
+
+use enum_dispatch::enum_dispatch;
+use serde::{Deserialize, Serialize};
+use uuid::Uuid;
+
+const SAVE_FILE: &'static str = "world.bin";
+
+fn main() {
+    let mut world = match std::fs::read(SAVE_FILE) {
+        Ok(data) => bincode::deserialize(&data).unwrap(),
+        Err(_) => {
+            let mut world = World::default();
+            let mut site = Site::new(
+                "Gorbo's Keep",
+                fastrand::usize(1..5)
+                    .try_into()
+                    .expect("Generated site with size of 0"),
+            );
+            site.populate_randomly();
+            world.sites.push(site);
+            std::fs::write("world.bin", bincode::serialize(&world).unwrap()).unwrap();
+            world
+        }
+    };
+
+    for site in world.sites.iter() {
+        println!("{site}")
+    }
+
+    let mut input = String::new();
+    loop {
+        std::io::stdin().read_line(&mut input).unwrap();
+        if vec!["q", "quit", "exit"]
+            .iter()
+            .any(|quit_cmd| input.trim() == *quit_cmd)
+        {
+            break;
+        }
+        let start = std::time::Instant::now();
+        world.advance_time(Duration::from_secs(3600));
+        let end = std::time::Instant::now();
+        println!("World tick: {}us", end.sub(start).as_micros());
+    }
+}
+
+#[derive(Debug, Default, Serialize, Deserialize)]
+pub struct World {
+    pub sites: Vec<Site>,
+}
+
+impl World {
+    pub fn advance_time(&mut self, time: Duration) {
+        for site in self.sites.iter_mut() {
+            site.advance_time(time);
+        }
+    }
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct Site {
+    pub name: String,
+    areas: Vec<SiteArea>,
+    accumulated_time: Duration,
+}
+
+impl Site {
+    #[inline]
+    const fn minimum_tick() -> Duration {
+        Duration::from_secs(3600)
+    }
+
+    fn inner_tick(&mut self) {
+        for area in self.areas.iter_mut() {
+            match resolve_combat(&area.population, 600) {
+                Some(results) => {
+                    for death in results.kills {
+                        area.population
+                            .retain(|creature| creature.uuid != death.killed);
+                    }
+                }
+                None => {
+                    // If no combat, there is a chance of migration to other areas
+                }
+            }
+        }
+        println!("Tick! {}", self);
+    }
+
+    pub fn areas(&self) -> &Vec<SiteArea> {
+        self.areas.as_ref()
+    }
+
+    pub fn areas_mut(&mut self) -> &mut Vec<SiteArea> {
+        self.areas.as_mut()
+    }
+
+    pub fn populate_randomly(&mut self) {
+        let area_count = self.areas.len();
+        {
+            let min_count = area_count;
+            let max_count = (5 + (area_count - 1) * 3).max(min_count);
+            for _ in 0..fastrand::usize(min_count..=max_count) {
+                let area_t = fastrand::f32().powi(2);
+                let index = (area_t * (area_count - 1) as f32).round() as usize;
+                self.areas
+                    .get_mut(index)
+                    .expect("Creature generation index for depth is out of bounds")
+                    .population
+                    .push(Creature::new(CreatureData::Bandit(Bandit::default())))
+            }
+        }
+        {
+            let min_count = 0;
+            let max_count = area_count.max(min_count);
+            for _ in 0..fastrand::usize(min_count..=max_count) {
+                let area_t = 1.0 - fastrand::f32().powi(2);
+                let index = (area_t * (area_count - 1) as f32).round() as usize;
+                self.areas
+                    .get_mut(index)
+                    .expect("Creature generation index for depth is out of bounds")
+                    .population
+                    .push(Creature::new(CreatureData::Spider(Spider::default())))
+            }
+        }
+    }
+
+    pub fn new(name: &str, size: NonZeroUsize) -> Self {
+        Self {
+            name: name.into(),
+            areas: vec![SiteArea::default(); size.get()],
+            accumulated_time: Duration::default(),
+        }
+    }
+
+    pub fn advance_time(&mut self, time: Duration) {
+        self.accumulated_time += time;
+        while self.accumulated_time >= Self::minimum_tick() {
+            self.inner_tick();
+            self.accumulated_time -= Self::minimum_tick();
+        }
+    }
+
+    /// Finds a creature with given uuid, removes it from the site and returns it with ownership
+    pub fn remove_by_uuid(&mut self, creature_uuid: Uuid) -> Option<Creature> {
+        for area in self.areas.iter_mut() {
+            for i in 0..area.population.len() {
+                if area.population[i].uuid == creature_uuid {
+                    return Some(area.population.swap_remove(i));
+                }
+            }
+        }
+        None
+    }
+}
+
+impl Display for Site {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "site \"{}\" [", self.name)?;
+        for (index, area) in self.areas.iter().enumerate() {
+            write!(f, "\n\tarea {} [", index)?;
+            for creature in area.population.iter() {
+                write!(f, "\n\t\t{}", creature)?;
+            }
+            if area.population.len() > 0 {
+                write!(f, "\n\t")?;
+            }
+            write!(f, "]")?;
+        }
+        if !self.areas.is_empty() {
+            write!(f, "\n")?;
+        }
+        write!(f, "]")
+    }
+}
+
+#[derive(Clone, Debug, Default, Serialize, Deserialize)]
+pub struct SiteArea {
+    pub population: Vec<Creature>,
+}
+
+#[derive(Clone, Eq, PartialEq, Hash, Debug, Serialize, Deserialize)]
+pub struct Creature {
+    pub uuid: Uuid,
+    pub data: CreatureData,
+}
+
+impl Display for Creature {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{} [{}]", self.data.species_id(), self.uuid)
+    }
+}
+
+impl Creature {
+    pub fn new(data: CreatureData) -> Self {
+        Self {
+            uuid: Uuid::new_v4(),
+            data,
+        }
+    }
+}
+
+#[enum_dispatch(CreatureData)]
+pub trait CreatureImpl {
+    fn species_id(&self) -> String;
+
+    fn initiative_modifier(&self) -> i8 {
+        0
+    }
+    fn threat_rating(&self) -> u8 {
+        1
+    }
+    fn ally_predicate(&self, other: &dyn CreatureImpl) -> bool {
+        self.species_id() == other.species_id()
+    }
+}
+
+#[derive(Clone, Debug, Eq, PartialEq, Hash, Serialize, Deserialize)]
+#[enum_dispatch]
+pub enum CreatureData {
+    Bandit(Bandit),
+    Spider(Spider),
+}
+
+#[derive(Clone, Debug, Default, Eq, PartialEq, Hash, Serialize, Deserialize)]
+pub struct Bandit {}
+
+impl CreatureImpl for Bandit {
+    fn species_id(&self) -> String {
+        "bandit".into()
+    }
+    fn threat_rating(&self) -> u8 {
+        2
+    }
+}
+
+#[derive(Clone, Debug, Default, Eq, PartialEq, Hash, Serialize, Deserialize)]
+pub struct Spider {}
+
+impl CreatureImpl for Spider {
+    fn species_id(&self) -> String {
+        "spider".into()
+    }
+    fn threat_rating(&self) -> u8 {
+        4
+    }
+    fn initiative_modifier(&self) -> i8 {
+        1
+    }
+}
+
+#[derive(Debug)]
+pub struct KillData {
+    pub killed: Uuid,
+    pub killer: Uuid,
+}
+
+#[derive(Debug)]
+pub struct CombatResults {
+    pub kills: Vec<KillData>,
+}
+
+#[derive(Debug)]
+struct CombatState {
+    initiative: i8,
+    health: u8,
+    damage: u8,
+    alive: bool,
+    enemies: HashSet<Uuid>,
+}
+
+impl CombatState {
+    pub fn from_creature(creature: &Creature) -> Self {
+        Self {
+            initiative: fastrand::i8(1..=4).saturating_add(creature.data.initiative_modifier()),
+            health: creature.data.threat_rating(),
+            damage: creature.data.threat_rating(),
+            alive: true,
+            enemies: HashSet::new(),
+        }
+    }
+}
+
+pub fn resolve_combat(combatants: &Vec<Creature>, max_rounds: u16) -> Option<CombatResults> {
+    let mut participants: HashMap<Uuid, CombatState> = HashMap::new();
+    for index_1 in 0..combatants.len() {
+        for index_2 in (index_1 + 1)..combatants.len() {
+            if index_1 == index_2 {
+                continue;
+            }
+            let c1 = &combatants[index_1];
+            let c2 = &combatants[index_2];
+            let is_enemy = !c1.data.ally_predicate(&c2.data) || !c2.data.ally_predicate(&c1.data);
+            if is_enemy {
+                if !participants.contains_key(&c1.uuid) {
+                    participants.insert(c1.uuid, CombatState::from_creature(&c1));
+                }
+                if !participants.contains_key(&c2.uuid) {
+                    participants.insert(c2.uuid, CombatState::from_creature(&c2));
+                }
+                participants
+                    .get_mut(&c1.uuid)
+                    .unwrap()
+                    .enemies
+                    .insert(c2.uuid);
+                participants
+                    .get_mut(&c2.uuid)
+                    .unwrap()
+                    .enemies
+                    .insert(c1.uuid);
+            }
+        }
+    }
+
+    if participants.is_empty() {
+        // No enemies in group :)
+        return None;
+    }
+
+    // Time for violence
+    let mut order: Vec<_> = participants.iter().collect();
+    order.sort_unstable_by_key(|(_, combat_state)| -combat_state.initiative);
+    let order: Vec<Uuid> = order.iter().map(|(uuid, _)| **uuid).collect();
+    let mut kills: HashMap<Uuid, Uuid> = HashMap::new();
+
+    for _ in 0..max_rounds {
+        let should_continue = participants.iter().any(|(_, combat)| {
+            combat.alive && combat.enemies.iter().any(|uuid| participants[uuid].alive)
+        });
+        if !should_continue {
+            break;
+        }
+
+        for uuid in order.iter() {
+            if !participants[uuid].alive {
+                continue;
+            }
+            let targets: Vec<_> = participants[uuid]
+                .enemies
+                .iter()
+                .filter(|enemy_uuid| participants[*enemy_uuid].alive)
+                .collect();
+            let target = match fastrand::choice(targets.iter()) {
+                Some(target) => **target,
+                None => continue,
+            };
+            let damage = participants[uuid].damage;
+            let enemy = participants.get_mut(&target).unwrap();
+            enemy.health = enemy.health.saturating_sub(fastrand::u8(0..=damage));
+            if enemy.health == 0 {
+                enemy.alive = false;
+                kills.insert(target, *uuid);
+            }
+        }
+    }
+
+    Some(CombatResults {
+        kills: kills
+            .iter()
+            .map(|(killed, killer)| KillData {
+                killed: *killed,
+                killer: *killer,
+            })
+            .collect(),
+    })
+}
diff --git a/world.bin b/world.bin
new file mode 100644
index 0000000..dc631a7
Binary files /dev/null and b/world.bin differ