1 files changed, 36 insertions, 2 deletions
diff --git a/src/main.rs b/src/main.rs
index 9d98cc9..2f608df 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -39,6 +39,26 @@ macro_rules! unwrap {
     };
 }
 
+macro_rules! debug {
+    ($($arg:tt)*) => {
+        if debug_enabled() {
+            use std::io::Write;
+            let stderr = ::std::io::stderr();
+            let mut lock = stderr.lock();
+            write!(lock, "[d] ");
+            writeln!(lock, $($arg)*);
+        }
+    }
+}
+
+static mut DEBUG_ENABLED: bool = false;
+
+/// Return whether or not debug output should be enabled.
+#[inline]
+fn debug_enabled() -> bool {
+    unsafe { DEBUG_ENABLED }
+}
+
 /// A program that allows you to search through all your evtc logs for specific
 /// people.
 #[derive(StructOpt, Debug)]
@@ -65,6 +85,10 @@ pub struct Opt {
     #[structopt(long = "no-color")]
     no_color: bool,
 
+    /// Print more debugging information to stderr.
+    #[structopt(long = "debug")]
+    debug: bool,
+
     /// The regular expression to search for.
     #[structopt(name = "EXPR")]
     expression: Regex,
@@ -162,6 +186,11 @@ fn main() {
         colored::control::set_override(false);
     }
 
+    if opt.debug {
+        // We haven't started any threads here yet, so this is fine.
+        unsafe { DEBUG_ENABLED = true };
+    }
+
     let result = grep(&opt);
     match result {
         Ok(_) => {}
@@ -216,6 +245,7 @@ fn search_log(entry: &DirEntry, opt: &Opt) -> Result<Option<LogResult>, RuntimeE
     let log = if let Some(e) = parsed {
         e
     } else {
+        debug!("log file cannot be parsed: {:?}", entry.path());
         return Ok(None);
     };
 
@@ -233,9 +263,10 @@ fn search_log(entry: &DirEntry, opt: &Opt) -> Result<Option<LogResult>, RuntimeE
 /// Extract human-readable information from the given log file.
 fn extract_info(entry: &DirEntry, log: &Log) -> LogResult {
     let bosses = log.boss_agents();
-    let boss_name = if bosses.len() == 1 {
+    let boss_name = if bosses.len() >= 1 {
         unwrap! { AgentName::Single(s) = bosses[0].name() => { s } }
     } else {
+        debug!("log file no boss agents: {:?}", entry.path());
         "<unknown>"
     }.into();
 
@@ -324,6 +355,9 @@ fn get_profession_name(profession: u32, elite: u32) -> &'static str {
         (8, 60) => "Scourge",
         (9, 63) => "Renegade",
 
-        _ => "Unknown",
+        _ => {
+            debug!("Unknown spec (prof: {}, elite: {})", profession, elite);
+            "Unknown"
+        },
     }
 }