use crate::config::CONFIG;
use crate::error::{AuthError, Result};
use regex::Regex;
use tracing::debug;
pub fn extract_token(html: &str) -> Result<String> {
debug!("Extracting token from HTML ({} bytes)", html.len());
let re = Regex::new(r#"(?i)name=["']_token["']\s+value=["']([^"'<>]+)["']"#)?;
if let Some(caps) = re.captures(html) {
let token = caps[1].to_string();
debug!("Regex found token: {}...", &token[..token.len().min(8)]);
return validate_token(&token);
}
if let Some(token) = manual_extract(html) {
debug!("Manual scan found token");
return validate_token(&token);
}
Err(AuthError::TokenNotFound)
}
fn manual_extract(html: &str) -> Option<String> {
let needle_name = "name=\"_token\"";
let needle_name_single = "name='_token'";
let value_pat = "value=";
let mut start = 0;
while let Some(pos) = html[start..].find(needle_name) {
let abs = start + pos;
if let Some(token) = extract_value_after(&html[abs..]) {
return Some(token);
}
start = abs + 1;
}
start = 0;
while let Some(pos) = html[start..].find(needle_name_single) {
let abs = start + pos;
if let Some(token) = extract_value_after(&html[abs..]) {
return Some(token);
}
start = abs + 1;
}
let mut idx = 0;
while let Some(val_pos) = html[idx..].find(value_pat) {
let abs = val_pos + idx;
let after = &html[abs + 6..];
let quote = after.chars().next()?;
if quote != '"' && quote != '\'' {
idx = abs + 1;
continue;
}
let end = after[1..].find(quote)?;
let token = &after[1..=end];
let ctx_start = if abs > 200 { abs - 200 } else { 0 };
let context = &html[ctx_start..abs];
if context.contains("name=\"_token\"") || context.contains("name='_token'") {
return Some(token.to_string());
}
idx = abs + 1;
}
None
}
fn extract_value_after(slice: &str) -> Option<String> {
let value_pat = "value=";
let pos = slice.find(value_pat)?;
let after = &slice[pos + 6..];
let quote = after.chars().next()?;
if quote != '"' && quote != '\'' {
return None;
}
let end = after[1..].find(quote)?;
Some(after[1..=end].to_string())
}
fn validate_token(token: &str) -> Result<String> {
let len = token.len();
if len < CONFIG.token_min_length {
return Err(AuthError::TokenInvalid {
reason: format!("too short (min {})", CONFIG.token_min_length),
});
}
if len > CONFIG.token_max_length {
return Err(AuthError::TokenInvalid {
reason: format!("too long (max {})", CONFIG.token_max_length),
});
}
let valid = token.chars().all(|c| {
c.is_ascii_alphanumeric() || c == '_' || c == '-' || c == '+' || c == '=' || c == '/'
});
if !valid {
return Err(AuthError::TokenInvalid {
reason: "contains invalid characters".into(),
});
}
Ok(token.to_string())
}