10 files changed, 1427 insertions, 0 deletions
diff --git a/scripts/Cargo.toml b/scripts/Cargo.toml
new file mode 100644
index 0000000..45dbd47
--- /dev/null
+++ b/scripts/Cargo.toml
@@ -0,0 +1,15 @@
+[package]
+name = "scripts"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+wasmtime = "14"
+rayon = "1"
+thiserror = "1"
+rand = "0.8"
+chrono = "0.4"
+log = "0.4"
+libm = "0.2"
diff --git a/scripts/src/lib.rs b/scripts/src/lib.rs
new file mode 100644
index 0000000..214001c
--- /dev/null
+++ b/scripts/src/lib.rs
@@ -0,0 +1,318 @@
+use std::{collections::HashMap, path::Path};
+
+pub use vtable::VTableScript;
+use wasmtime::{Engine, IntoFunc, Linker, Module, Store};
+
+pub use wasm::InvalidWasmScript;
+use wasm::{WasmScript, WasmScriptState};
+
+mod libs;
+mod vtable;
+mod wasm;
+
+/// A sturcture to contain and use any needed scripts.
+///
+/// # Performance
+///
+/// V-Table scripts are faster than WebAssembly scripts. WebAssembly scripting
+/// is provided to make hot-reloading possible. Either way, scripts should be
+/// reasonably fast.
+///
+/// A single long WebAssembly script is typically faster than lots of small
+/// scripts. Try to keep the number of scripts small. No more than twenty
+/// scripts should be enabled at once.
+#[derive(Default)]
+pub struct ScriptManager {
+	script_map: HashMap<Box<str>, ScriptId>,
+
+	vtable_scripts: Vec<Script<VTableScript>>,
+	wasm_scripts: Vec<Script<WasmScript>>,
+
+	relink_every_frame: bool,
+	wasm_engine: Engine,
+	wasm_imports: Linker<WasmScriptState>,
+}
+
+impl ScriptManager {
+	/// Creates a new, empty script manager
+	pub fn new() -> Self {
+		let wasm_engine = Engine::default();
+		let mut wasm_imports = Linker::new(&wasm_engine);
+		wasm_imports.allow_shadowing(true);
+
+		let mut this = Self {
+			script_map: HashMap::new(),
+			vtable_scripts: Vec::new(),
+			wasm_scripts: Vec::new(),
+			relink_every_frame: false,
+			wasm_imports,
+			wasm_engine,
+		};
+		libs::add_alligator_library(&mut this);
+
+		this
+	}
+
+	/// If set to `true`, then every frame, the scripts will be relinked with
+	/// it's dependencies on each call.
+	///
+	/// The main reason to do this would be to ensure that the state is reset
+	/// each frame. However, the link is slow, so it's not recommended to use
+	/// this setting for releasing a game. This is only recommended for
+	/// debugging.
+	pub fn set_relink_every_frame(&mut self, setting: bool) {
+		self.relink_every_frame = setting;
+	}
+
+	/// Returns `true` if the scripts are set to be relinked each frame. See
+	/// [`set_relink_every_frame`] for more details.
+	pub fn relink_every_frame(&self) -> bool {
+		self.relink_every_frame
+	}
+
+	/// Adds a script to this manager.
+	///
+	/// By  default, all scripts are disabled. To enable it, call
+	/// [`enable_script`].
+	pub fn add_vtable_script(&mut self, name: Box<str>, script: VTableScript) -> ScriptId {
+		let idx = self.vtable_scripts.len();
+		self.vtable_scripts.push(Script::new(script));
+		let id = ScriptId {
+			kind: ScriptKind::VTable,
+			idx,
+		};
+		self.script_map.insert(name, id);
+		id
+	}
+
+	/// Adds a WebAssembly script to this manager.
+	///
+	/// By  default, all scripts are disabled. To enable it, call
+	/// [`enable_script`].
+	///
+	/// # Errors
+	///
+	/// This function returns an error if it could not use the given script.
+	pub fn add_wasm_script(
+		&mut self,
+		name: Box<str>,
+		path: impl AsRef<Path>,
+		trusted: bool,
+	) -> Result<ScriptId, InvalidWasmScript> {
+		let idx = self.vtable_scripts.len();
+		let script = WasmScript::new(
+			path.as_ref(),
+			&self.wasm_engine,
+			&self.wasm_imports,
+			trusted,
+		)?;
+		self.wasm_scripts.push(Script::new(script));
+		let id = ScriptId {
+			kind: ScriptKind::Wasm,
+			idx,
+		};
+		self.script_map.insert(name, id);
+		Ok(id)
+	}
+
+	/// Add a WebAssembly module which can be called by other WebAssembly
+	/// scripts.
+	///
+	/// If there are two libraries with the same name, only the newest module
+	/// is used. This feature can be used to allow libraries to be hot
+	/// reloaded.
+	///
+	/// The `trusted` parameter refers to whether this library can call
+	/// functions which require trust.
+	///
+	/// # Performance
+	///
+	/// Running this function relinks all WebAssembly scripts. For best
+	/// performance, all WebAssembly libraries should be added before any
+	/// scripts are loaded.
+	pub fn add_wasm_library(
+		&mut self,
+		name: &str,
+		path: impl AsRef<Path>,
+		trusted: bool,
+	) -> Result<(), InvalidWasmScript> {
+		let module = Module::from_file(&self.wasm_engine, path)?;
+		let mut store = Store::new(&self.wasm_engine, WasmScriptState::new(trusted));
+		let instance = self.wasm_imports.instantiate(&mut store, &module)?;
+		self.wasm_imports.instance(store, name, instance)?;
+
+		for script in &mut self.wasm_scripts {
+			if let Err(e) = script.inner.relink(&self.wasm_engine, &self.wasm_imports) {
+				log::error!("{e}");
+			}
+		}
+
+		Ok(())
+	}
+
+	/// Reloads a WebAssembly script from disk.
+	pub fn reload_script(&mut self, name: &str) -> Option<Result<(), InvalidWasmScript>> {
+		let id = self.script_map.get(name).unwrap();
+		let result = match id.kind {
+			ScriptKind::Wasm => self
+				.wasm_scripts
+				.get_mut(id.idx)
+				.unwrap()
+				.inner
+				.reload(&self.wasm_engine, &self.wasm_imports),
+			_ => return None,
+		};
+		Some(result)
+	}
+
+	/// Adds a library to the manager
+	pub fn add_library_function<Params, Args>(
+		&mut self,
+		module: &str,
+		name: &str,
+		func: impl IntoFunc<WasmScriptState, Params, Args> + Clone,
+	) -> Option<()> {
+		self.wasm_imports.func_wrap(module, name, func).ok()?;
+		Some(())
+	}
+
+	/// Checks if the script with the given name is enabled
+	pub fn is_script_enabled(&self, name: &str) -> Option<bool> {
+		let id = self.script_map.get(name)?;
+		let enabled = match id.kind {
+			ScriptKind::VTable => self.vtable_scripts.get(id.idx)?.is_enabled(),
+			ScriptKind::Wasm => self.wasm_scripts.get(id.idx)?.is_enabled(),
+		};
+		Some(enabled)
+	}
+
+	/// Checks if the script with the given name is trusted
+	pub fn is_script_trusted(&self, name: &str) -> Option<bool> {
+		let id = self.script_map.get(name)?;
+		let trusted = match id.kind {
+			ScriptKind::VTable => true,
+			ScriptKind::Wasm => self.wasm_scripts.get(id.idx)?.inner.is_trusted(),
+		};
+		Some(trusted)
+	}
+
+	/// This enables the script, allowing it to run each frame.
+	///
+	/// Calling this automatically calls the `begin` function for the script.
+	pub fn enable_script(&mut self, name: &str) -> Option<()> {
+		let id = self.script_map.get(name)?;
+		match id.kind {
+			ScriptKind::VTable => {
+				let script = self.vtable_scripts.get_mut(id.idx)?;
+				if script.is_enabled() {
+					// avoid calling `begin` if the script is already enabled
+					return Some(());
+				}
+
+				script.enable();
+				script.inner.begin();
+			}
+			ScriptKind::Wasm => {
+				let script = self.wasm_scripts.get_mut(id.idx)?;
+				if script.is_enabled() {
+					return Some(());
+				}
+
+				script.enable();
+				if let Err(e) = script.inner.begin() {
+					log::error!("{}", e);
+				}
+			}
+		};
+		Some(())
+	}
+
+	/// This disables the script, preventing it from running
+	pub fn disable_script(&mut self, name: &str) -> Option<()> {
+		let id = self.script_map.get(name)?;
+		match id.kind {
+			ScriptKind::VTable => self.vtable_scripts.get_mut(id.idx)?.disable(),
+			ScriptKind::Wasm => self.wasm_scripts.get_mut(id.idx)?.disable(),
+		};
+		Some(())
+	}
+
+	/// This allows the script to run functions which require trust
+	pub fn trust_script(&mut self, name: &str) -> Option<()> {
+		let id = self.script_map.get(name)?;
+		if id.kind == ScriptKind::Wasm {
+			self.wasm_scripts.get_mut(id.idx)?.inner.trust();
+		}
+		Some(())
+	}
+
+	/// This prevents the script from running functions which require trust
+	pub fn untrust_script(&mut self, name: &str) -> Option<()> {
+		let id = self.script_map.get(name)?;
+		if id.kind == ScriptKind::Wasm {
+			self.wasm_scripts.get_mut(id.idx)?.inner.untrust();
+		}
+		Some(())
+	}
+
+	/// Runs the `update` function for all enabled scripts
+	pub fn run_update_scripts(&mut self) {
+		for script in &mut self.vtable_scripts {
+			if script.is_enabled() {
+				script.inner.update();
+			}
+		}
+
+		for script in &mut self.wasm_scripts {
+			if script.is_enabled() {
+				if self.relink_every_frame {
+					if let Err(e) = script.inner.relink(&self.wasm_engine, &self.wasm_imports) {
+						log::error!("{e}");
+					}
+				}
+				if let Err(e) = script.inner.update() {
+					log::error!("{}", e);
+				}
+			}
+		}
+	}
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+enum ScriptKind {
+	VTable,
+	Wasm,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct ScriptId {
+	kind: ScriptKind,
+	idx: usize,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+struct Script<S> {
+	inner: S,
+	enabled: bool,
+}
+
+impl<S> Script<S> {
+	fn new(inner: S) -> Self {
+		Self {
+			inner,
+			enabled: true,
+		}
+	}
+
+	fn is_enabled(&self) -> bool {
+		self.enabled
+	}
+
+	fn enable(&mut self) {
+		self.enabled = true;
+	}
+
+	fn disable(&mut self) {
+		self.enabled = false;
+	}
+}
diff --git a/scripts/src/libs/allocate.rs b/scripts/src/libs/allocate.rs
new file mode 100644
index 0000000..7f2825d
--- /dev/null
+++ b/scripts/src/libs/allocate.rs
@@ -0,0 +1,76 @@
+use wasmtime::Caller;
+
+use crate::{ScriptManager, WasmScriptState};
+
+use super::{
+	system::{_alloc, _get_memory},
+	LIBRARY_NAME,
+};
+
+fn allocate_zeroed(mut caller: Caller<'_, WasmScriptState>, size: u32, align: u32) -> u32 {
+	let Some((ptr, data)) = _alloc(&mut caller, size, align) else {
+		return 0;
+	};
+
+	data.fill(0);
+	ptr
+}
+
+fn reallocate(
+	mut caller: Caller<'_, WasmScriptState>,
+	ptr: u32,
+	size: u32,
+	new_size: u32,
+	align: u32,
+) -> u32 {
+	if new_size < size {
+		return ptr;
+	}
+
+	let bump_pointer = &mut caller.data_mut().bump_pointer;
+	if *bump_pointer == ptr + size {
+		*bump_pointer = ptr;
+		let Some((new_ptr, _)) = _alloc(&mut caller, new_size, align) else {
+			return 4;
+		};
+		return new_ptr;
+	}
+
+	let (_, original) = _get_memory(&mut caller);
+	let Some(original) = original.get(ptr as usize..(ptr + size) as usize) else {
+		return 4;
+	};
+	let original = original.to_vec();
+
+	let Some((new_ptr, data)) = _alloc(&mut caller, new_size, align) else {
+		return 0;
+	};
+
+	data.get_mut(..size as usize)
+		.unwrap()
+		.clone_from_slice(&original);
+	new_ptr
+}
+
+fn duplicate(mut caller: Caller<'_, WasmScriptState>, ptr: u32, size: u32, align: u32) -> u32 {
+	let (_, original) = _get_memory(&mut caller);
+	let Some(original) = original.get(ptr as usize..(ptr + size) as usize) else {
+		return 4;
+	};
+	let original = original.to_vec();
+
+	let Some((new_ptr, data)) = _alloc(&mut caller, size, align) else {
+		return 0;
+	};
+
+	data.clone_from_slice(&original);
+	new_ptr
+}
+
+pub fn library(manager: &mut ScriptManager) -> Option<()> {
+	manager.add_library_function(LIBRARY_NAME, "calloc", allocate_zeroed)?;
+	manager.add_library_function(LIBRARY_NAME, "realloc", reallocate)?;
+	manager.add_library_function(LIBRARY_NAME, "memdup", duplicate)?;
+
+	Some(())
+}
diff --git a/scripts/src/libs/buffer.rs b/scripts/src/libs/buffer.rs
new file mode 100644
index 0000000..b4cee77
--- /dev/null
+++ b/scripts/src/libs/buffer.rs
@@ -0,0 +1,182 @@
+use wasmtime::Caller;
+
+use crate::{ScriptManager, WasmScriptState};
+
+use super::{system::_get_memory, LIBRARY_NAME};
+
+fn memory_search(mut caller: Caller<'_, WasmScriptState>, ptr: u32, ch: u32, len: u32) -> u32 {
+	let (_, mem_ptr) = _get_memory(&mut caller);
+	let len = len as usize;
+	let ptr = ptr as usize;
+	let ch = ch as u8;
+	if (len + ptr) > mem_ptr.len() {
+		return 4;
+	}
+
+	for i in 0..len {
+		if mem_ptr[ptr + i] == ch {
+			return (ptr + i) as u32;
+		}
+	}
+
+	0
+}
+
+fn memory_search_last(mut caller: Caller<'_, WasmScriptState>, ptr: u32, ch: u32, len: u32) -> u32 {
+	let (_, mem_ptr) = _get_memory(&mut caller);
+	let len = len as usize;
+	let ptr = ptr as usize;
+	let ch = ch as u8;
+	if (len + ptr) > mem_ptr.len() {
+		return 4;
+	}
+
+	for i in 0..len {
+		let index = ptr + len - i - 1;
+		if mem_ptr[index] == ch {
+			return index as u32;
+		}
+	}
+
+	0
+}
+
+fn memory_compare(
+	mut caller: Caller<'_, WasmScriptState>,
+	lhs: u32,
+	rhs: u32,
+	len: u32,
+) -> (u32, u32) {
+	let (_, mem_ptr) = _get_memory(&mut caller);
+	let len = len as usize;
+	let lhs = lhs as usize;
+	let rhs = rhs as usize;
+	if (len + lhs) > mem_ptr.len() || (len + rhs) > mem_ptr.len() {
+		return (4, 0);
+	}
+
+	for i in 0..len {
+		let diff = mem_ptr[lhs + i] - mem_ptr[rhs + i];
+		if diff != 0 {
+			return (0, diff as u32);
+		}
+	}
+
+	(0, 0)
+}
+
+fn memory_fill(mut caller: Caller<'_, WasmScriptState>, dest: u32, ch: u32, len: u32) -> u32 {
+	let (_, mem_ptr) = _get_memory(&mut caller);
+	let len = len as usize;
+	let dest = dest as usize;
+	let ch = ch as u8;
+
+	if (len + dest) > mem_ptr.len() {
+		return 4;
+	}
+
+	for i in 0..len {
+		mem_ptr[dest + i] = ch;
+	}
+
+	0
+}
+
+fn memory_copy(mut caller: Caller<'_, WasmScriptState>, dest: u32, src: u32, len: u32) -> u32 {
+	let (_, mem_ptr) = _get_memory(&mut caller);
+	let len = len as usize;
+	let dest = dest as usize;
+	let src = src as usize;
+	if (len + dest) > mem_ptr.len() || (len + src) > mem_ptr.len() {
+		return 4;
+	}
+
+	// check for overlap
+	if (dest < src && dest + len > src) || (src < dest && src + len > dest) {
+		let src = mem_ptr[src..src + len].to_vec();
+		let dest = &mut mem_ptr[dest..dest + len];
+		dest.clone_from_slice(&src);
+	} else {
+		for i in 0..len {
+			mem_ptr[dest + i] = mem_ptr[src + i];
+		}
+	}
+
+	0
+}
+
+fn memory_copy_until(
+	mut caller: Caller<'_, WasmScriptState>,
+	dest: u32,
+	src: u32,
+	len: u32,
+	delimiter: u32,
+) -> u32 {
+	let (_, mem_ptr) = _get_memory(&mut caller);
+	let len = len as usize;
+	let dest = dest as usize;
+	let src = src as usize;
+	let delimiter = delimiter as u8;
+	if (len + dest) > mem_ptr.len() || (len + src) > mem_ptr.len() {
+		return 4;
+	}
+
+	// check for overlap
+	if (dest < src && dest + len > src) || (src < dest && src + len > dest) {
+		let cloned_src = mem_ptr[src..src + len].to_vec();
+		let dest = &mut mem_ptr[dest..dest + len];
+		for i in 0..len {
+			let ch = cloned_src[i];
+			dest[i] = ch;
+			if ch == delimiter {
+				return (src + i + 1) as u32;
+			}
+		}
+	} else {
+		for i in 0..len {
+			let ch = mem_ptr[src + i];
+			mem_ptr[dest + i] = ch;
+			if ch == delimiter {
+				return (src + i + 1) as u32;
+			}
+		}
+	}
+
+	0
+}
+
+fn memory_concatenate(
+	mut caller: Caller<'_, WasmScriptState>,
+	dest: u32,
+	src: u32,
+	dest_len: u32,
+	src_len: u32,
+) -> u32 {
+	let (_, mem_ptr) = _get_memory(&mut caller);
+	let dest = dest as usize;
+	let src = src as usize;
+	let dest_len = dest_len as usize;
+	let src_len = src_len as usize;
+	if (dest_len + src_len + dest) > mem_ptr.len() || (src_len + src) > mem_ptr.len() {
+		return 4;
+	}
+
+	let src = mem_ptr[src..src + src_len].to_vec();
+	let dest_offset = dest + dest_len;
+	let dest = &mut mem_ptr[dest_offset..dest_offset + src_len];
+	dest.clone_from_slice(&src);
+
+	0
+}
+
+pub fn library(manager: &mut ScriptManager) -> Option<()> {
+	manager.add_library_function(LIBRARY_NAME, "memchr", memory_search)?;
+	manager.add_library_function(LIBRARY_NAME, "memrchr", memory_search_last)?;
+	manager.add_library_function(LIBRARY_NAME, "memcmp", memory_compare)?;
+	manager.add_library_function(LIBRARY_NAME, "memset", memory_fill)?;
+	manager.add_library_function(LIBRARY_NAME, "memcpy", memory_copy)?;
+	manager.add_library_function(LIBRARY_NAME, "memccpy", memory_copy_until)?;
+	manager.add_library_function(LIBRARY_NAME, "memcat", memory_concatenate)?;
+
+	Some(())
+}
diff --git a/scripts/src/libs/ctype.rs b/scripts/src/libs/ctype.rs
new file mode 100644
index 0000000..ca4f326
--- /dev/null
+++ b/scripts/src/libs/ctype.rs
@@ -0,0 +1,85 @@
+use crate::{libs::LIBRARY_NAME, ScriptManager};
+
+fn char_is(func: impl Fn(char) -> bool, ch: u32) -> u32 {
+	let Some(ch) = char::from_u32(ch) else {
+		return 0;
+	};
+
+	func(ch) as u32
+}
+
+macro_rules! ctype {
+	(fn $fn_name: ident => $fn: expr;) => {
+		fn $fn_name(ch: u32) -> u32 {
+			char_is($fn, ch)
+		}
+	};
+	(fn $fn_name: ident => $fn: expr; $(fn $fn_name2: ident => $fn2: expr;)*) => {
+		fn $fn_name(ch: u32) -> u32 {
+			char_is($fn, ch)
+		}
+		ctype!($(fn $fn_name2 => $fn2;)*);
+	};
+}
+
+ctype!(
+	fn is_alphanumeric => |ch| ch.is_alphanumeric();
+	fn is_alphabetic => |ch| ch.is_alphabetic();
+	fn is_lowercase => |ch| ch.is_lowercase();
+	fn is_uppercase => |ch| ch.is_uppercase();
+	fn is_control => |ch| ch.is_control();
+	fn is_whitespace => |ch| ch.is_whitespace();
+	fn is_ascii_alphanumeric => |ch| ch.is_ascii_alphanumeric();
+	fn is_ascii_alphabetic => |ch| ch.is_ascii_alphabetic();
+	fn is_ascii_lowercase => |ch| ch.is_ascii_lowercase();
+	fn is_ascii_uppercase => |ch| ch.is_ascii_lowercase();
+	fn is_ascii_digit => |ch| ch.is_ascii_digit();
+	fn is_ascii_hexdigit => |ch| ch.is_ascii_hexdigit();
+	fn is_ascii_control => |ch| ch.is_ascii_control();
+	fn is_ascii_graphical => |ch| ch.is_ascii_graphic();
+	fn is_ascii_whitespace => |ch| ch.is_ascii_whitespace();
+	fn is_ascii_blank => |ch| ch == ' ' || ch == '\t';
+	fn is_ascii_printable => |ch| ch.is_alphanumeric() || ch.is_ascii_punctuation();
+	fn is_ascii_punctuation => |ch| ch.is_ascii_punctuation();
+);
+
+fn to_ascii_lower(ch: u32) -> u32 {
+	let Some(ch) = char::from_u32(ch) else {
+		return ch;
+	};
+
+	ch.to_ascii_lowercase() as u32
+}
+
+fn to_ascii_upper(ch: u32) -> u32 {
+	let Some(ch) = char::from_u32(ch) else {
+		return ch;
+	};
+
+	ch.to_ascii_uppercase() as u32
+}
+
+pub fn library(manager: &mut ScriptManager) -> Option<()> {
+	manager.add_library_function(LIBRARY_NAME, "iswalnum", is_alphanumeric)?;
+	manager.add_library_function(LIBRARY_NAME, "iswalpha", is_alphabetic)?;
+	manager.add_library_function(LIBRARY_NAME, "iswlower", is_lowercase)?;
+	manager.add_library_function(LIBRARY_NAME, "iswupper", is_uppercase)?;
+	manager.add_library_function(LIBRARY_NAME, "iswcntrl", is_control)?;
+	manager.add_library_function(LIBRARY_NAME, "iswspace", is_whitespace)?;
+	manager.add_library_function(LIBRARY_NAME, "isalnum", is_ascii_alphanumeric)?;
+	manager.add_library_function(LIBRARY_NAME, "isalpha", is_ascii_alphabetic)?;
+	manager.add_library_function(LIBRARY_NAME, "islower", is_ascii_lowercase)?;
+	manager.add_library_function(LIBRARY_NAME, "isupper", is_ascii_uppercase)?;
+	manager.add_library_function(LIBRARY_NAME, "isdigit", is_ascii_digit)?;
+	manager.add_library_function(LIBRARY_NAME, "isxdigit", is_ascii_hexdigit)?;
+	manager.add_library_function(LIBRARY_NAME, "iscntrl", is_ascii_control)?;
+	manager.add_library_function(LIBRARY_NAME, "isgraph", is_ascii_graphical)?;
+	manager.add_library_function(LIBRARY_NAME, "isspace", is_ascii_whitespace)?;
+	manager.add_library_function(LIBRARY_NAME, "isblank", is_ascii_blank)?;
+	manager.add_library_function(LIBRARY_NAME, "isprint", is_ascii_printable)?;
+	manager.add_library_function(LIBRARY_NAME, "ispunct", is_ascii_punctuation)?;
+	manager.add_library_function(LIBRARY_NAME, "tolower", to_ascii_lower)?;
+	manager.add_library_function(LIBRARY_NAME, "toupper", to_ascii_upper)?;
+
+	Some(())
+}
diff --git a/scripts/src/libs/math.rs b/scripts/src/libs/math.rs
new file mode 100644
index 0000000..4aae3c3
--- /dev/null
+++ b/scripts/src/libs/math.rs
@@ -0,0 +1,398 @@
+use crate::ScriptManager;
+
+use super::LIBRARY_NAME;
+
+fn abs_i32(n: i32) -> i32 {
+	n.abs()
+}
+
+fn abs_i64(n: i64) -> i64 {
+	n.abs()
+}
+
+fn mod_f32(x: f32, y: f32) -> f32 {
+	libm::fmodf(x, y)
+}
+
+fn mod_f64(x: f64, y: f64) -> f64 {
+	libm::fmod(x, y)
+}
+
+fn remainder_f32(x: f32, y: f32) -> f32 {
+	libm::remainderf(x, y)
+}
+
+fn remainder_f64(x: f64, y: f64) -> f64 {
+	libm::remainder(x, y)
+}
+
+fn mul_add_f32(x: f32, y: f32, z: f32) -> f32 {
+	x.mul_add(y, z)
+}
+
+fn mul_add_f64(x: f64, y: f64, z: f64) -> f64 {
+	x.mul_add(y, z)
+}
+
+fn fdim_f32(x: f32, y: f32) -> f32 {
+	libm::fdimf(x, y)
+}
+
+fn fdim_f64(x: f64, y: f64) -> f64 {
+	libm::fdim(x, y)
+}
+
+fn exp_f32(x: f32) -> f32 {
+	x.exp()
+}
+
+fn exp_f64(x: f64) -> f64 {
+	x.exp()
+}
+
+fn exp2_f32(x: f32) -> f32 {
+	x.exp2()
+}
+
+fn exp2_f64(x: f64) -> f64 {
+	x.exp2()
+}
+
+fn expm1_f32(x: f32) -> f32 {
+	x.exp_m1()
+}
+
+fn expm1_f64(x: f64) -> f64 {
+	x.exp_m1()
+}
+
+fn ln_f32(x: f32) -> f32 {
+	x.ln()
+}
+
+fn ln_f64(x: f64) -> f64 {
+	x.ln()
+}
+
+fn log10_f32(x: f32) -> f32 {
+	x.log10()
+}
+
+fn log10_f64(x: f64) -> f64 {
+	x.log10()
+}
+
+fn log2_f32(x: f32) -> f32 {
+	x.log2()
+}
+
+fn log2_f64(x: f64) -> f64 {
+	x.log2()
+}
+
+fn ln1p_f32(x: f32) -> f32 {
+	x.ln_1p()
+}
+
+fn ln1p_f64(x: f64) -> f64 {
+	x.ln_1p()
+}
+
+fn pow_f32(base: f32, exponent: f32) -> f32 {
+	base.powf(exponent)
+}
+
+fn pow_f64(base: f64, exponent: f64) -> f64 {
+	base.powf(exponent)
+}
+
+fn cbrt_f32(x: f32) -> f32 {
+	x.cbrt()
+}
+
+fn cbrt_f64(x: f64) -> f64 {
+	x.cbrt()
+}
+
+fn hypotenuse_f32(x: f32, y: f32) -> f32 {
+	x.hypot(y)
+}
+
+fn hypotenuse_f64(x: f64, y: f64) -> f64 {
+	x.hypot(y)
+}
+
+fn sin_f32(x: f32) -> f32 {
+	x.sin()
+}
+
+fn sin_f64(x: f64) -> f64 {
+	x.sin()
+}
+
+fn cos_f32(x: f32) -> f32 {
+	x.cos()
+}
+
+fn cos_f64(x: f64) -> f64 {
+	x.cos()
+}
+
+fn tan_f32(x: f32) -> f32 {
+	x.tan()
+}
+
+fn tan_f64(x: f64) -> f64 {
+	x.tan()
+}
+
+fn asin_f32(x: f32) -> f32 {
+	x.asin()
+}
+
+fn asin_f64(x: f64) -> f64 {
+	x.asin()
+}
+
+fn acos_f32(x: f32) -> f32 {
+	x.acos()
+}
+
+fn acos_f64(x: f64) -> f64 {
+	x.acos()
+}
+
+fn atan_f32(x: f32) -> f32 {
+	x.atan()
+}
+
+fn atan_f64(x: f64) -> f64 {
+	x.atan()
+}
+
+fn sinh_f32(x: f32) -> f32 {
+	x.sinh()
+}
+
+fn sinh_f64(x: f64) -> f64 {
+	x.sinh()
+}
+
+fn cosh_f32(x: f32) -> f32 {
+	x.cosh()
+}
+
+fn cosh_f64(x: f64) -> f64 {
+	x.cosh()
+}
+
+fn tanh_f32(x: f32) -> f32 {
+	x.tanh()
+}
+
+fn tanh_f64(x: f64) -> f64 {
+	x.tanh()
+}
+
+fn asinh_f32(x: f32) -> f32 {
+	x.asinh()
+}
+
+fn asinh_f64(x: f64) -> f64 {
+	x.asinh()
+}
+
+fn acosh_f32(x: f32) -> f32 {
+	x.acosh()
+}
+
+fn acosh_f64(x: f64) -> f64 {
+	x.acosh()
+}
+
+fn atanh_f32(x: f32) -> f32 {
+	x.atanh()
+}
+
+fn atanh_f64(x: f64) -> f64 {
+	x.atanh()
+}
+
+fn erf_f32(x: f32) -> f32 {
+	libm::erff(x)
+}
+
+fn erf_f64(x: f64) -> f64 {
+	libm::erf(x)
+}
+
+fn erfc_f32(x: f32) -> f32 {
+	libm::erfcf(x)
+}
+
+fn erfc_f64(x: f64) -> f64 {
+	libm::erfc(x)
+}
+
+fn gamma_f32(x: f32) -> f32 {
+	libm::tgammaf(x)
+}
+
+fn gamma_f64(x: f64) -> f64 {
+	libm::tgamma(x)
+}
+
+fn ln_gamma_f32(x: f32) -> f32 {
+	libm::lgammaf(x)
+}
+
+fn ln_gamma_f64(x: f64) -> f64 {
+	libm::lgamma(x)
+}
+
+fn round_f32_i32(x: f32) -> i32 {
+	x.round() as i32
+}
+
+fn round_f64_i32(x: f64) -> i32 {
+	x.round() as i32
+}
+
+fn round_f32_i64(x: f32) -> i64 {
+	x.round() as i64
+}
+
+fn round_f64_i64(x: f64) -> i64 {
+	x.round() as i64
+}
+
+fn frexp_f32(x: f32) -> (f32, i32) {
+	libm::frexpf(x)
+}
+
+fn frexp_f64(x: f64) -> (f64, i32) {
+	libm::frexp(x)
+}
+
+fn ldexp_f32(x: f32, exp: i32) -> f32 {
+	libm::ldexpf(x, exp)
+}
+
+fn ldexp_f64(x: f64, exp: i32) -> f64 {
+	libm::ldexp(x, exp)
+}
+
+fn modf_f32(x: f32) -> (f32, f32) {
+	libm::modff(x)
+}
+
+fn modf_f64(x: f64) -> (f64, f64) {
+	libm::modf(x)
+}
+
+fn logb_f32(x: f32) -> i32 {
+	libm::ilogbf(x)
+}
+
+fn logb_f64(x: f64) -> i32 {
+	libm::ilogb(x)
+}
+
+fn next_after_f32(from: f32, to: f32) -> f32 {
+	libm::nextafterf(from, to)
+}
+
+fn next_after_f64(from: f64, to: f64) -> f64 {
+	libm::nextafter(from, to)
+}
+
+fn copy_sign_f32(x: f32, y: f32) -> f32 {
+	libm::copysignf(x, y)
+}
+
+fn copy_sign_f64(x: f64, y: f64) -> f64 {
+	libm::copysign(x, y)
+}
+
+pub fn library(manager: &mut ScriptManager) -> Option<()> {
+	manager.add_library_function(LIBRARY_NAME, "abs", abs_i32)?;
+	manager.add_library_function(LIBRARY_NAME, "labs", abs_i64)?;
+	manager.add_library_function(LIBRARY_NAME, "modf", mod_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "mod", mod_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "remf", remainder_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "rem", remainder_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "fmaf", mul_add_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "fma", mul_add_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "fdimf", fdim_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "fdim", fdim_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "expf", exp_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "exp", exp_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "exp2f", exp2_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "exp2", exp2_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "expm1f", expm1_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "expm1", expm1_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "lnf", ln_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "ln", ln_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "log2f", log2_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "log2", log2_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "log10f", log10_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "log10", log10_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "ln1pf", ln1p_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "ln1p", ln1p_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "powf", pow_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "pow", pow_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "cbrtf", cbrt_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "cbrt", cbrt_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "hypotf", hypotenuse_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "hypot", hypotenuse_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "sinf", sin_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "sin", sin_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "cosf", cos_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "cos", cos_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "tanf", tan_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "tan", tan_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "asinf", asin_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "asin", asin_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "acosf", acos_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "acos", acos_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "atanf", atan_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "atan", atan_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "sinhf", sinh_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "sinh", sinh_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "coshf", cosh_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "cosh", cosh_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "tanhf", tanh_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "tanh", tanh_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "asinhf", asinh_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "asinh", asinh_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "acoshf", acosh_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "acosh", acosh_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "atanhf", atanh_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "atanh", atanh_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "erff", erf_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "erf", erf_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "erfcf", erfc_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "erfc", erfc_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "gammaf", gamma_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "gamma", gamma_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "lgammaf", ln_gamma_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "lgamma", ln_gamma_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "lroundf", round_f32_i32)?;
+	manager.add_library_function(LIBRARY_NAME, "lround", round_f64_i32)?;
+	manager.add_library_function(LIBRARY_NAME, "llroundf", round_f32_i64)?;
+	manager.add_library_function(LIBRARY_NAME, "llround", round_f64_i64)?;
+	manager.add_library_function(LIBRARY_NAME, "frexpf", frexp_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "frexp", frexp_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "ldexpf", ldexp_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "ldexp", ldexp_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "modff", modf_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "modf", modf_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "ilogbf", logb_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "ilogb", logb_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "nextafterf", next_after_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "nextafter", next_after_f64)?;
+	manager.add_library_function(LIBRARY_NAME, "copysignf", copy_sign_f32)?;
+	manager.add_library_function(LIBRARY_NAME, "copysign", copy_sign_f64)?;
+
+	Some(())
+}
diff --git a/scripts/src/libs/mod.rs b/scripts/src/libs/mod.rs
new file mode 100644
index 0000000..c6b1ffc
--- /dev/null
+++ b/scripts/src/libs/mod.rs
@@ -0,0 +1,19 @@
+use crate::ScriptManager;
+
+mod allocate;
+mod buffer;
+mod ctype;
+mod math;
+mod system;
+
+const LIBRARY_NAME: &str = "alligator";
+
+pub fn add_alligator_library(manager: &mut ScriptManager) -> Option<()> {
+	allocate::library(manager)?;
+	buffer::library(manager)?;
+	ctype::library(manager)?;
+	math::library(manager)?;
+	system::library(manager)?;
+
+	Some(())
+}
diff --git a/scripts/src/libs/system.rs b/scripts/src/libs/system.rs
new file mode 100644
index 0000000..e2d0ddb
--- /dev/null
+++ b/scripts/src/libs/system.rs
@@ -0,0 +1,154 @@
+use std::mem::align_of;
+use std::{borrow::Cow, process::Command};
+
+use chrono::Offset;
+use wasmtime::{Caller, Memory};
+
+use crate::{ScriptManager, WasmScriptState};
+
+use super::LIBRARY_NAME;
+
+pub fn _get_memory<'a>(caller: &'a mut Caller<WasmScriptState>) -> (Memory, &'a mut [u8]) {
+	let memory = caller.get_export("memory").unwrap().into_memory().unwrap();
+	let mem_ptr = memory.data_mut(caller);
+	(memory, mem_ptr)
+}
+
+fn _get_string<'a>(
+	caller: &'a mut Caller<WasmScriptState>,
+	offset: u32,
+	length: u32,
+) -> Option<Cow<'a, str>> {
+	let (_, mem_ptr) = _get_memory(caller);
+	if (offset as usize + length as usize) > mem_ptr.len() {
+		return None;
+	}
+
+	Some(String::from_utf8_lossy(
+		&mem_ptr[offset as usize..length as usize],
+	))
+}
+
+fn _log(caller: &mut Caller<WasmScriptState>, level: log::Level, message: u32, length: u32) -> u32 {
+	let Some(message) = _get_string(caller, message, length) else {
+		return 4;
+	};
+	log::log!(level, "{}", message);
+	0
+}
+
+pub fn _alloc<'a>(
+	mut caller: &'a mut Caller<WasmScriptState>,
+	size: u32,
+	align: u32,
+) -> Option<(u32, &'a mut [u8])> {
+	// find bumper location in memory
+	let bump_offset = caller.data().bump_pointer;
+	let (memory, memory_ptr) = _get_memory(caller);
+	let bump_ptr = &memory_ptr[bump_offset as usize..];
+
+	// calculate pointer to the new allocation
+	let offset = bump_ptr.as_ptr().align_offset(align as usize);
+	let new_offset = bump_offset + offset as u32;
+
+	// update bump pointer
+	let bump_offset = &mut caller.data_mut().bump_pointer;
+	*bump_offset = new_offset + size;
+
+	// grow memory if necessary
+	let bump_offset = *bump_offset;
+	if memory.data_size(&caller) < bump_offset as usize {
+		let delta = (size + offset as u32) / (64 * 1024) + 1;
+		if memory.grow(&mut caller, delta as u64).is_err() {
+			return None;
+		}
+	}
+
+	let new_ptr = &mut _get_memory(caller).1[new_offset as usize..size as usize];
+	Some((new_offset, new_ptr))
+}
+
+fn allocate(mut caller: Caller<WasmScriptState>, size: u32, align: u32) -> u32 {
+	match _alloc(&mut caller, size, align) {
+		Some((ptr, _)) => ptr,
+		None => 0,
+	}
+}
+
+fn free_sized(mut caller: Caller<'_, WasmScriptState>, ptr: u32, size: u32) -> u32 {
+	let bump_offset = &mut caller.data_mut().bump_pointer;
+	if ptr + size == *bump_offset {
+		*bump_offset = ptr;
+	}
+
+	0
+}
+
+fn free_aligned_sized(
+	caller: Caller<'_, WasmScriptState>,
+	ptr: u32,
+	_alignment: u32,
+	size: u32,
+) -> u32 {
+	free_sized(caller, ptr, size)
+}
+
+fn env_var(mut caller: Caller<'_, WasmScriptState>, name: u32, length: u32) -> u32 {
+	let Some(name) = _get_string(&mut caller, name, length) else {
+		return 4;
+	};
+	let Ok(value) = std::env::var(name.to_string()) else {
+		return 1;
+	};
+
+	let Some((offset, ptr)) = _alloc(&mut caller, value.len() as u32, align_of::<u8>() as u32)
+	else {
+		return 0;
+	};
+	ptr.clone_from_slice(value.as_bytes());
+
+	offset
+}
+
+fn random_number() -> u64 {
+	rand::random()
+}
+
+fn current_time_utc() -> (i64, u32) {
+	let duration = chrono::Utc::now() - chrono::DateTime::<chrono::Utc>::MIN_UTC;
+	(
+		duration.num_seconds(),
+		duration.to_std().unwrap().subsec_nanos(),
+	)
+}
+
+fn local_offset() -> i32 {
+	chrono::Local::now().offset().fix().local_minus_utc()
+}
+
+fn log(mut caller: Caller<'_, WasmScriptState>, message: u32, length: u32) {
+	_log(&mut caller, log::Level::Info, message, length);
+}
+
+fn log_warn(mut caller: Caller<'_, WasmScriptState>, message: u32, length: u32) {
+	_log(&mut caller, log::Level::Warn, message, length);
+}
+
+fn log_error(mut caller: Caller<'_, WasmScriptState>, message: u32, length: u32) {
+	_log(&mut caller, log::Level::Error, message, length);
+}
+
+pub fn library(manager: &mut ScriptManager) -> Option<()> {
+	manager.add_library_function(LIBRARY_NAME, "aligned_alloc", allocate)?;
+	manager.add_library_function(LIBRARY_NAME, "free_sized", free_sized)?;
+	manager.add_library_function(LIBRARY_NAME, "free_aligned_sized", free_aligned_sized)?;
+	manager.add_library_function(LIBRARY_NAME, "env_var", env_var)?;
+	manager.add_library_function(LIBRARY_NAME, "random_number", random_number)?;
+	manager.add_library_function(LIBRARY_NAME, "current_time_utc", current_time_utc)?;
+	manager.add_library_function(LIBRARY_NAME, "local_offset", local_offset)?;
+	manager.add_library_function(LIBRARY_NAME, "log", log)?;
+	manager.add_library_function(LIBRARY_NAME, "log_warn", log_warn)?;
+	manager.add_library_function(LIBRARY_NAME, "log_error", log_error)?;
+
+	Some(())
+}
diff --git a/scripts/src/vtable.rs b/scripts/src/vtable.rs
new file mode 100644
index 0000000..0fbb324
--- /dev/null
+++ b/scripts/src/vtable.rs
@@ -0,0 +1,10 @@
+/// A trait for scripts
+pub trait ScriptTable: Send + Sync {
+	/// This is called whenever the script is enabled
+	fn begin(&mut self);
+
+	/// This is called every frame
+	fn update(&mut self);
+}
+
+pub type VTableScript = &'static mut dyn ScriptTable;
diff --git a/scripts/src/wasm.rs b/scripts/src/wasm.rs
new file mode 100644
index 0000000..7ac9dae
--- /dev/null
+++ b/scripts/src/wasm.rs
@@ -0,0 +1,170 @@
+use std::path::Path;
+
+use thiserror::Error;
+use wasmtime::{Engine, Instance, Linker, Module, Mutability, Store, ValType};
+
+// It's a bad idea to have the memory allocator return a number that could also
+// indicate an error, so this is set to be at least eight.
+const MIN_BUMP_POINTER: u32 = 8;
+
+/// Information about the script which can be used by functions it calls
+pub struct WasmScriptState {
+	pub bump_pointer: u32,
+	pub trusted: bool,
+}
+
+impl WasmScriptState {
+	pub const fn new(trusted: bool) -> Self {
+		Self {
+			bump_pointer: MIN_BUMP_POINTER,
+			trusted,
+		}
+	}
+}
+
+/// A script, its path in the filesystem, and some metadata
+pub struct WasmScript {
+	path: Box<Path>,
+	module: Module,
+	store: Store<WasmScriptState>,
+	instance: Instance,
+	trusted: bool,
+	//state: Value,
+}
+
+#[derive(Debug, Error)]
+pub enum InvalidWasmScript {
+	#[error("There is no exported memory called 'memory', which is required")]
+	NoExportedMemory,
+	#[error("The exported symbol, 'memory' must be a memory")]
+	MemoryIsNotAMemory,
+	#[error("The memory must be 32-bit, not 64-bit")]
+	MemoryTooLarge,
+	#[error("There is no exported global called '__heap_base', which is required")]
+	NoHeapBase,
+	#[error("The exported symbol, '__heap_base' must be a constant global")]
+	HeapBaseIsNotGlobal,
+	#[error("The exported global, '__heap_base' must be an i32")]
+	HeapBaseMustBeI32,
+	#[error("The exported global, '__heap_base' must be a constant")]
+	HeapBaseMustBeConstant,
+	#[error("{}", .0)]
+	CompilerError(#[from] wasmtime::Error),
+}
+
+/// Confirms that the module can be used as a script
+fn validate_module(module: &Module) -> Result<(), InvalidWasmScript> {
+	// verify that memory is exported from this module and is valid
+	let Some(export) = module.get_export("memory") else {
+		return Err(InvalidWasmScript::NoExportedMemory);
+	};
+	let Some(memory) = export.memory() else {
+		return Err(InvalidWasmScript::MemoryIsNotAMemory);
+	};
+	if memory.is_64() {
+		return Err(InvalidWasmScript::MemoryTooLarge);
+	}
+
+	// verify __heap_base global
+	let Some(export) = module.get_export("__heap_base") else {
+		return Err(InvalidWasmScript::NoHeapBase);
+	};
+	let Some(heap_base) = export.global() else {
+		return Err(InvalidWasmScript::HeapBaseIsNotGlobal);
+	};
+	if *heap_base.content() != ValType::I32 {
+		return Err(InvalidWasmScript::HeapBaseMustBeI32);
+	}
+	if heap_base.mutability() != Mutability::Const {
+		return Err(InvalidWasmScript::HeapBaseMustBeConstant);
+	}
+
+	Ok(())
+}
+
+impl WasmScript {
+	pub fn new(
+		path: &Path,
+		engine: &Engine,
+		linker: &Linker<WasmScriptState>,
+		trusted: bool,
+	) -> Result<Self, InvalidWasmScript> {
+		let module = Module::from_file(engine, path)?;
+		validate_module(&module)?;
+		let mut store = Store::new(engine, WasmScriptState::new(trusted));
+		let instance = linker.instantiate(&mut store, &module)?;
+
+		Ok(Self {
+			path: path.into(),
+			module,
+			store,
+			instance,
+			trusted,
+		})
+	}
+
+	/// Reload from the filesystem
+	pub fn reload(
+		&mut self,
+		engine: &Engine,
+		linker: &Linker<WasmScriptState>,
+	) -> Result<(), InvalidWasmScript> {
+		let module = Module::from_file(engine, &self.path)?;
+		validate_module(&module)?;
+		self.store = Store::new(engine, WasmScriptState::new(self.trusted));
+		self.instance = linker.instantiate(&mut self.store, &module)?;
+
+		Ok(())
+	}
+
+	/// Re-links the module. This doesn't load the module from the filesystem.
+	pub fn relink(
+		&mut self,
+		engine: &Engine,
+		linker: &Linker<WasmScriptState>,
+	) -> Result<(), InvalidWasmScript> {
+		self.store = Store::new(engine, WasmScriptState::new(self.trusted));
+		self.instance = linker.instantiate(&mut self.store, &self.module)?;
+		Ok(())
+	}
+
+	pub fn is_trusted(&self) -> bool {
+		self.trusted
+	}
+
+	pub fn trust(&mut self) {
+		self.trusted = true;
+	}
+
+	pub fn untrust(&mut self) {
+		self.trusted = false;
+	}
+
+	fn run_function_if_exists(&mut self, name: &str) -> wasmtime::Result<()> {
+		// set bump pointer to the start of the heap
+		let heap_base = self
+			.instance
+			.get_global(&mut self.store, "__heap_base")
+			.unwrap()
+			.get(&mut self.store)
+			.unwrap_i32();
+		let bump_ptr = &mut self.store.data_mut().bump_pointer;
+		*bump_ptr = (heap_base as u32).max(MIN_BUMP_POINTER);
+
+		// call the given function
+		let func = self.instance.get_func(&mut self.store, name);
+		if let Some(func) = func {
+			func.call(&mut self.store, &[], &mut [])?;
+		}
+
+		Ok(())
+	}
+
+	pub fn begin(&mut self) -> wasmtime::Result<()> {
+		self.run_function_if_exists("begin")
+	}
+
+	pub fn update(&mut self) -> wasmtime::Result<()> {
+		self.run_function_if_exists("update")
+	}
+}