1 files changed, 191 insertions, 0 deletions
diff --git a/resource.ha b/resource.ha
new file mode 100644
index 0000000..6b393f2
--- /dev/null
+++ b/resource.ha
@@ -0,0 +1,191 @@
+use bufio;
+use dejson;
+use encoding::json;
+use errors;
+use fs;
+use io;
+use os;
+use path;
+use strings;
+use trace;
+
+def MISSINGNO = "minecraft:missingno";
+def BUILTIN_MISSING = "minecraft:builtin/missing";
+
+type Pack = struct {
+	fs: *fs::fs,
+	kind: str,
+};
+
+fn resource_splitpath(path: str) (str, str, str, str, str) = {
+	const (base, path) = strings::cut(path, "/");
+	const (ns, path) = strings::cut(path, "/");
+	const (kind, path) = strings::cut(path, "/");
+	const bnameindex = match (strings::rindex(path, '/')) {
+	case let index: size =>
+		yield index + 1;
+	case void =>
+		yield 0z;
+	};
+	const extindex = match (strings::rindex(
+		strings::sub(path, bnameindex, strings::end), '.')) {
+	case let index: size =>
+		yield bnameindex + index;
+	case void =>
+		yield len(path);
+	};
+	const name = strings::sub(path, 0, extindex);
+	const ext = strings::sub(path, extindex, strings::end);
+	return (base, ns, kind, name, ext);
+};
+
+fn resource_open(
+	pack: *Pack,
+	kind: str,
+	ident: str,
+	ext: str,
+	tr: *trace::tracer,
+) (io::handle | trace::failed) = {
+	const (ns, name) = ident_split(ident);
+	const fname = strings::concat(name, ext);
+	defer free(fname);
+	let path = path::init()!;
+	if (path::set(&path, pack.kind, ns, kind, fname) is path::too_long) {
+		return trace::error(tr, "Path too long");
+	};
+	const path = path::string(&path);
+
+	match (fs::open(pack.fs, path, fs::flag::RDONLY)) {
+	case let f: io::handle =>
+		return f;
+	case let err: fs::error =>
+		return trace::error(tr, "open: {}", fs::strerror(err));
+	};
+};
+
+fn resource_load_json(
+	pack: *Pack,
+	kind: str,
+	ident: str,
+	ext: str,
+	tr: *trace::tracer,
+) (json::value | trace::failed) = {
+	const f = resource_open(pack, kind, ident, ext, tr)?;
+
+	let rbuf: [os::BUFSZ]u8 = [0...];
+	let buf = bufio::init(f, rbuf, []);
+
+	const json = match (json::load(&buf)) {
+	case let json: json::value =>
+		yield json;
+	case let err: json::error =>
+		io::close(f): void;
+		return trace::error(tr, "Invalid JSON: {}",
+			json::strerror(err));
+	};
+
+	match (io::close(f)) {
+	case void => void;
+	case let err: io::error =>
+		json::finish(json);
+		return trace::error(tr, "close: {}", io::strerror(err));
+	};
+
+	return json;
+};
+
+fn resource_search(
+	pack: *Pack,
+	kind: str,
+	exts: str...
+) [](str, str) = {
+	const tr = trace::ctx(&trace::root, "resource search");
+
+	let out: [](str, str) = [];
+	let path = path::init()!;
+
+	const it = match (fs::iter(pack.fs, pack.kind)) {
+	case let x: *fs::iterator =>
+		yield x;
+	case let err: fs::error =>
+		trace::error(&tr, "{}: fs::iter: {}",
+			pack.kind, fs::strerror(err)): void;
+		return out;
+	};
+	defer fs::finish(it);
+	for (true) match (fs::next(it)) {
+	case let ent: fs::dirent =>
+		if (!fs::isdir(ent.ftype)) continue;
+		if (strings::hasprefix(ent.name, ".")) continue;
+		if (path::set(&path, pack.kind, ent.name, kind)
+				is path::too_long) {
+
+			trace::error(&tr, "{}/{}/{}: Path too long",
+				pack.kind, ent.name, kind): void;
+			continue;
+		};
+		resource_search_ns(pack, &out, path::string(&path), &tr, exts...);
+	case done => break;
+	};
+
+	return out;
+};
+
+fn resource_search_ns(
+	pack: *Pack,
+	out: *[](str, str),
+	parent: str,
+	tr: *trace::tracer,
+	exts: str...
+) void = {
+	let path = path::init()!;
+
+	const it = match (fs::iter(pack.fs, parent)) {
+	case let x: *fs::iterator =>
+		yield x;
+	case errors::noentry =>
+		return;
+	case let err: fs::error =>
+		trace::error(tr, "{}: fs::iter: {}",
+			parent, fs::strerror(err)): void;
+		return;
+	};
+	defer fs::finish(it);
+	for (true) match (fs::next(it)) {
+	case let ent: fs::dirent =>
+		if (strings::hasprefix(ent.name, ".")) continue;
+		if (path::set(&path, parent, ent.name) is path::too_long) {
+			trace::error(tr, "{}/{}: Path too long",
+				parent, ent.name): void;
+			continue;
+		};
+		const path = path::string(&path);
+		if (fs::isdir(ent.ftype)) {
+			resource_search_ns(pack, out, path, tr, exts...);
+		} else if (fs::isfile(ent.ftype)) {
+			const (_, ns, _, name, ext) =
+				resource_splitpath(path);
+			for (let i = 0z; i < len(exts); i += 1) {
+				if (ext == exts[i]) {
+					const ident = ident_make(ns, name);
+					// yes, this borrow from input is
+					// intentional. needs to be documented
+					// later.
+					append(out, (ident, exts[i]));
+					break;
+				};
+			};
+		};
+	case done => break;
+	};
+};
+
+fn wassert_fields(de: *dejson::deser, names: str...) (void | dejson::error) = {
+	dejson::object(de)?;
+	match (dejson::assert_fields(de, names...)) {
+	case let err: dejson::error =>
+		defer free(err);
+		trace::warn(&trace::root, "{}", err);
+	case void => void;
+	};
+};