1 files changed, 105 insertions, 0 deletions
diff --git a/src/bin/aft.rs b/src/bin/aft.rs
new file mode 100644
index 0000000..0ada921
--- /dev/null
+++ b/src/bin/aft.rs
@@ -0,0 +1,105 @@
+
+/*
+ * Default behavior:
+ *
+ *   aft < file.aft
+ *      pretty-prints as a table to stdout
+ *
+ *   ls | aft | aft-sort
+ *      detects non-aft stdin and converts to aft on stdout
+ */
+
+use std::str::FromStr;
+use std::io::{self, Read, Write, BufRead};
+use std::error::Error;
+use colored::*;
+
+#[derive(Debug)]
+enum AftFieldType {
+    Str,
+    Int,
+    Float,
+    Bool,
+    Array,
+    Null,
+    Other(String),
+}
+
+impl FromStr for AftFieldType {
+    type Err = Box<dyn Error>;
+
+    fn from_str(raw: &str) -> Result<AftFieldType, Box<dyn Error>> {
+        match raw {
+            "" => Ok(AftFieldType::Null),
+            "str" => Ok(AftFieldType::Str),
+            "int" | "integer" => Ok(AftFieldType::Int),
+            "float" => Ok(AftFieldType::Float),
+            "bool" | "boolean" => Ok(AftFieldType::Bool),
+            "array" => Ok(AftFieldType::Array),
+            other => Ok(AftFieldType::Other(other.to_string())),
+
+        }
+    }
+}
+
+#[derive(Debug)]
+struct AftHeader {
+    col_names: Vec<String>,
+    col_types: Option<Vec<AftFieldType>>,
+}
+
+fn main() -> Result<(), Box<dyn Error>> {
+
+    let mut stdout = io::stdout();
+    let stdin = io::stdin();
+    let mut stdin = stdin.lock();
+
+    // if we aren't connected to terminal, just pass through
+    if !atty::is(atty::Stream::Stdout) {
+        io::copy(&mut stdin, &mut stdout)?;
+        return Ok(())
+    }
+
+    // read first byte of input to check if we are getting AFT; if not just pass through
+    let mut first_byte = [0; 1];
+    let got = stdin.read(&mut first_byte)?;
+    if got != 1 {
+        panic!("couldn't read a byte from stdin");
+    };
+    if first_byte[0] != 0x01 {
+        stdout.write(&first_byte)?;
+        io::copy(&mut stdin, &mut stdout)?;
+        return Ok(())
+    }
+
+    let mut stdin = io::BufReader::new(stdin);
+    let mut header_bytes = vec![];
+    // TODO: sanity limit on length
+    stdin.read_until(0x02, &mut header_bytes)?;
+    if header_bytes[header_bytes.len()-1] != 0x02 {
+        panic!("expected an AFT header");
+    };
+    let header_string = String::from_utf8_lossy(&header_bytes);
+    let header_rows: Vec<&str> = header_string.splitn(2, "\n").collect();
+    let header = match header_rows.len() {
+        0 => panic!("expected a header"),
+        1 => AftHeader {
+            col_names: header_rows[0].split("\x1E").map(|v| v.to_string()).collect(),
+            col_types: None,
+        },
+        _ => AftHeader {
+            col_names: header_rows[0].split("\x1E").map(|v| v.to_string()).collect(),
+            col_types: Some(header_rows[1].split("\x1E").map(|v| AftFieldType::from_str(v)).collect::<Result<Vec<AftFieldType>, Box<dyn Error>>>()?),
+        },
+    };
+
+    let mut tw = tabwriter::TabWriter::new(stdout);
+    writeln!(tw, "{}", header.col_names.join("\t").bold())?;
+    for line in stdin.lines() {
+        let line = line?;
+        writeln!(tw, "{}", line.replace("\x1E", "\t"))?;
+    }
+    tw.flush()?;
+
+    Ok(())
+}