use std::path::PathBuf;
use backhopper_core::{Arity, BehaviourName, FunctionName, ModuleName};
use backhopper_erlang_scan::{skip_char_literal_span, split_top_level_commas};
use backhopper_xref_graph::{Deprecation, DeprecationTier, FunctionSig};
use crate::errors::ReadWarning;
use crate::macros::parse_define;
use crate::reader::scan::ModuleBuilder;
use crate::scanner::Scanner;
pub(super) fn consume_attribute_body<'a>(sc: &mut Scanner<'a>) -> &'a str {
let start = sc.pos().byte_offset as usize;
let mut depth = 0i32;
while let Some(byte) = sc.peek() {
match byte {
b'(' | b'[' | b'{' => {
depth += 1;
sc.advance();
}
b')' | b']' | b'}' => {
depth -= 1;
sc.advance();
}
b'.' if depth <= 0 => {
let end = sc.pos().byte_offset as usize;
sc.advance();
return sc.src_slice(start, end);
}
b'"' => sc.consume_string(),
b'~' => sc.consume_sigil_or_advance(),
b'\'' => sc.consume_quoted_atom(),
b'$' => sc.consume_char_literal(),
b'%' => sc.skip_line(),
_ => {
sc.advance();
}
}
}
sc.src_slice(start, sc.pos().byte_offset as usize)
}
pub(super) fn handle_attribute(
name: &str,
body: &str,
b: &mut ModuleBuilder,
warnings: &mut Vec<ReadWarning>,
) {
let trimmed = body
.trim()
.trim_start_matches('(')
.trim_end_matches(')')
.trim();
match name {
"module" => {
if let Ok(m) = ModuleName::new(trimmed.to_owned()) {
b.set_module(m, warnings);
} else {
warnings.push(ReadWarning::UnsupportedQuotedModuleName {
path: b.path.clone(),
raw: trimmed.to_owned(),
});
}
}
"export" => {
for sig in parse_export_list(trimmed) {
b.explicit_export_decls.insert(sig);
}
}
"behaviour" | "behavior" => {
if let Ok(beh) = BehaviourName::new(trimmed.to_owned()) {
b.behaviours.insert(beh);
}
}
"callback" => {
if let Some(sig) = parse_callback_signature(trimmed) {
b.callbacks.insert(sig);
}
}
"optional_callbacks" => {
for sig in parse_export_list(trimmed) {
b.optional_callbacks.insert(sig);
}
}
"import" => {
if let Some((module, sigs)) = parse_import(trimmed) {
b.imports.entry(module).or_default().extend(sigs);
}
}
"deprecated" => {
for (sig, dep) in parse_deprecated(trimmed) {
b.deprecated.insert(sig, dep);
}
}
"on_load" => {
if let Some(sig) = parse_on_load(trimmed) {
b.on_load = Some(sig);
}
}
"define" => {
if let Some((key, value)) = parse_define(trimmed) {
b.macros.insert(key, value);
}
}
"include" | "include_lib" => {
if let Some(path) = parse_include_path(trimmed) {
b.include_paths.push(path);
}
}
_ => {}
}
}
fn parse_include_path(body: &str) -> Option<PathBuf> {
let s = body
.trim()
.trim_start_matches('(')
.trim_end_matches(')')
.trim();
let s = s.strip_prefix('"')?;
let s = s.strip_suffix('"')?;
if s.is_empty() {
return None;
}
Some(PathBuf::from(s))
}
fn parse_export_list(body: &str) -> Vec<FunctionSig> {
let s = body
.trim()
.trim_start_matches('[')
.trim_end_matches(']')
.trim();
let mut out = Vec::new();
for item in split_top_level_commas(s) {
let item = item.trim();
if let Some((name, arity)) = item.rsplit_once('/') {
if let (Ok(name), Ok(arity)) = (
FunctionName::new(name.trim().to_owned()),
arity.trim().parse::<u8>(),
) {
out.push(FunctionSig::new(name, Arity::new(arity)));
}
}
}
out
}
fn parse_callback_signature(body: &str) -> Option<FunctionSig> {
let body = body.trim();
let (name_raw, after_open) = body.split_once('(')?;
let name = FunctionName::new(name_raw.trim().to_owned()).ok()?;
let args = extract_balanced_arg_list(after_open)?;
let arity = count_top_level_args(args);
Some(FunctionSig::new(name, Arity::new(arity)))
}
fn extract_balanced_arg_list(after_open: &str) -> Option<&str> {
let bytes = after_open.as_bytes();
let mut depth: i32 = 0;
let mut in_string = false;
let mut in_quote = false;
let mut i = 0usize;
while i < bytes.len() {
let c = bytes[i];
if !in_string && !in_quote && c == b'$' && i + 1 < bytes.len() {
i += skip_char_literal_span(bytes, i);
continue;
}
match c {
b'(' if !in_string && !in_quote => depth += 1,
b')' if !in_string && !in_quote => {
if depth == 0 {
return Some(&after_open[..i]);
}
depth -= 1;
}
b'"' if !in_quote => in_string = !in_string,
b'\'' if !in_string => in_quote = !in_quote,
_ => {}
}
i += 1;
}
None
}
fn parse_import(body: &str) -> Option<(ModuleName, Vec<FunctionSig>)> {
let s = body.trim();
let (module_part, rest) = s.split_once(',')?;
let module = ModuleName::new(module_part.trim().to_owned()).ok()?;
Some((module, parse_export_list(rest)))
}
fn parse_deprecated(body: &str) -> Vec<(FunctionSig, Deprecation)> {
let inner = body
.trim()
.trim_start_matches('[')
.trim_end_matches(']')
.trim();
let mut out = Vec::new();
for tup in split_top_level_commas(inner) {
let tup = tup
.trim()
.trim_start_matches('{')
.trim_end_matches('}')
.trim();
let parts: Vec<&str> = split_top_level_commas(tup)
.into_iter()
.map(str::trim)
.collect();
if parts.len() < 2 {
continue;
}
let (Ok(name), Ok(arity)) = (
FunctionName::new(parts[0].to_owned()),
parts[1].parse::<u8>(),
) else {
continue;
};
let sig = FunctionSig::new(name, Arity::new(arity));
let mut tier = DeprecationTier::Eventual;
let mut message: Option<String> = None;
if let Some(third) = parts.get(2) {
let t = third.trim().trim_start_matches('"').trim_end_matches('"');
match t {
"next_version" | "next_release" | "next_major_release" => {
tier = DeprecationTier::Next;
}
"now" => tier = DeprecationTier::Now,
"eventually" => tier = DeprecationTier::Eventual,
_ => message = Some(t.to_owned()),
}
}
out.push((sig, Deprecation { tier, message }));
}
out
}
fn parse_on_load(body: &str) -> Option<FunctionSig> {
let s = body
.trim()
.trim_start_matches('{')
.trim_end_matches('}')
.trim();
let (name, arity) = s.split_once(',')?;
let name = FunctionName::new(name.trim().to_owned()).ok()?;
let arity = arity.trim().parse::<u8>().ok()?;
Some(FunctionSig::new(name, Arity::new(arity)))
}
pub(super) fn count_top_level_args(s: &str) -> u8 {
let s = s.trim();
if s.is_empty() {
return 0;
}
let parts = split_top_level_commas(s);
u8::try_from(parts.len()).unwrap_or(u8::MAX)
}