Adds header parsing with basic arguments

.vscode/launch.json

@@ -0,0 +1,45 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "lldb",
+            "request": "launch",
+            "name": "Debug executable 'wfdb_corrosion'",
+            "cargo": {
+                "args": [
+                    "build",
+                    "--bin=wfdb_corrosion",
+                    "--package=wfdb_corrosion"
+                ],
+                "filter": {
+                    "name": "wfdb_corrosion",
+                    "kind": "bin"
+                }
+            },
+            "args": [],
+            "cwd": "${workspaceFolder}"
+        },
+        {
+            "type": "lldb",
+            "request": "launch",
+            "name": "Debug unit tests in executable 'wfdb_corrosion'",
+            "cargo": {
+                "args": [
+                    "test",
+                    "--no-run",
+                    "--bin=wfdb_corrosion",
+                    "--package=wfdb_corrosion"
+                ],
+                "filter": {
+                    "name": "wfdb_corrosion",
+                    "kind": "bin"
+                }
+            },
+            "args": [],
+            "cwd": "${workspaceFolder}"
+        }
+    ]
+}

src/headproc.rs

@@ -0,0 +1,276 @@
+use std::{u64, vec};
+
+use crate::SignalFormat;
+
+/// Record information obtained from the header.
+/// 
+/// Only the `name`, `signal_count`, and `sampling_freq` values are required by default.
+#[derive(Debug, Clone)]
+struct Record {
+    name: String,
+    seg_num: Option<u64>,
+    signal_count: u64,
+    sampling_freq: u64,
+    counter_freq: Option<u64>,
+    base_counter_val: Option<u64>,
+    sample_num: Option<u64>,
+    basetime: Option<String>, // I dont thing we really need to care much about these
+    basedate: Option<String>
+}
+
+impl Record {
+    /// Attempts to generate the record information from a string
+    pub fn from_str(argument_line: &str) -> Result<Record, &str> {
+        let args: Vec<&str> = argument_line.split(' ').collect();
+        if  args.len() < 2 {
+            return Err("error: header file provided lacks sufficient record arguments.");
+        }
+        let name = args[0].to_string();
+        let seg_num: Option<u64>;
+        let sig_count: u64;
+        let sampling_freq: u64;
+        // Everything else is initialized with None, this is for sake of me not getting a stroke
+        let mut counter_freq: Option<u64> = None;
+        let base_counter_val: Option<u64> = None;
+        let sample_num: Option<u64> = None;
+        let basetime: Option<String> = None;
+        let basedate: Option<String> = None;
+
+
+        // Signals and segments are kept in a single argument organized as signal/segment
+        // segments are optional and we need to check this too
+        {
+            let seg_sig: Vec<&str> = args[1].split('/').collect();
+            if seg_sig.len() == 2 {
+                match seg_sig[1].parse::<u64>() {
+                    Ok(value) => {
+                        seg_num = Some(value);
+                    }
+                    Err(_) => {
+                        return Err("error: failed to parse segment number from header.");
+                    }
+                }
+            } else {
+                seg_num = None;
+            }
+            match seg_sig[0].parse::<u64>() {
+                Ok(value) => {
+                    sig_count = value;
+                }
+                Err(_) => {
+                    return Err("error: failed to parse signal number from header.");
+                }
+            }
+        }
+        
+        // Parse everything else, if present
+        loop { // This is apparently the way to get safe correct goto-like behaviour
+            if args.len() <= 2 { // Sampling frequency and counter frequency
+                sampling_freq = 250; // Default value
+                break;
+            }
+            
+            {
+                let freq_dual: Vec<&str> = args[2].split('/').collect();
+                if freq_dual.len() == 2 {
+                    match freq_dual[1].parse::<u64>() {
+                        Ok(value) => {
+                            counter_freq = Some(value);
+                        }
+                        Err(_) => {
+                            return Err("error: failed to parse counter frequency from header.");
+                        }
+                    }
+                }
+                match freq_dual[0].parse::<u64>() {
+                    Ok(value) => {
+                        sampling_freq = value;
+                    }
+                    Err(_) => {
+                        return Err("error: failed to parse sampling frequency from header.");
+                    }
+                }
+            }
+
+            // Todo: Other arguments in the standard
+
+            break;
+        }
+        Ok(Record { 
+            name: name, 
+            seg_num: seg_num,
+            signal_count: sig_count, 
+            sampling_freq: sampling_freq, 
+            counter_freq: counter_freq, 
+            base_counter_val: base_counter_val, 
+            sample_num: sample_num, 
+            basetime: basetime, 
+            basedate: basedate 
+        })
+    }
+}
+
+#[derive(Debug, Clone)]
+struct SignalSpec {
+    filename: String,
+    format: SignalFormat,
+    samples_frame: Option<u64>,
+    skew: Option<u64>,
+    offset: Option<u64>,
+    adc_gain: Option<f64>,
+    baseline: Option<u64>,
+    units: Option<String>,
+    adc_resolution: Option<u64>,
+    adc_zero: Option<u64>,
+    initial_val: Option<u64>,
+    checksum: Option<u64>,
+    blocksize: Option<u64>,
+    desc: Option<String>
+}
+
+impl SignalSpec {
+    /// Attempts to generate a valid signal specification struct from a supplied string.
+    /// Returns a `Result<SignalSpec, &str>` containing possible error information.
+    /// 
+    /// ## Arguments
+    /// - `argument_line` - argument line for the signal specification, taken from header file
+    pub fn from_str(argument_line: &str) -> Result<SignalSpec, &str> {
+        let args: Vec<&str> = argument_line.split(' ').collect();
+
+        if  args.len() < 2 {
+            return Err("error: signal provided by header file lacks sufficient arguments.");
+        }
+        let name = args[0].to_string();
+        let sigformat: SignalFormat;
+        // Optional args
+        let samples_frame: Option<u64> = None;
+        let skew: Option<u64> = None;
+        let offset: Option<u64> = None;
+        let adc_gain: Option<f64> = None;
+        let baseline: Option<u64> = None;
+        let units: Option<String> = None;
+        let adc_resolution: Option<u64> = None;
+        let adc_zero: Option<u64> = None;
+        let initial_val: Option<u64> = None;
+        let checksum: Option<u64> = None;
+        let blocksize: Option<u64> = None;
+        let desc: Option<String> = None;
+
+
+        match args[1].parse::<u64>() {
+            Ok(value) => {
+                sigformat = SignalSpec::parse_format(value);
+            },
+            Err(_) => {
+                return Err("error: unable to parse format from signal");
+            } 
+        }
+
+        
+        Ok(
+            SignalSpec { filename: name,
+                format: sigformat, 
+                samples_frame: samples_frame, 
+                skew: skew, offset: offset, 
+                adc_gain: adc_gain, 
+                baseline: baseline, 
+                units: units, 
+                adc_resolution: adc_resolution, 
+                adc_zero: adc_zero, 
+                initial_val: initial_val, 
+                checksum: checksum, 
+                blocksize: blocksize, 
+                desc: desc }
+        )
+    }
+
+    fn parse_format(formatnum: u64) -> SignalFormat {
+        match formatnum {
+            16 => SignalFormat::Format16,
+            212 => SignalFormat::Format212,
+            0..=u64::MAX => SignalFormat::Unimpl
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+pub struct Header {
+    record: Option<Record>,
+    signal_specs: Vec<SignalSpec>
+}
+
+impl Header {
+    /// Creates a completely empty, not fully initialized header
+    /// 
+    /// This is a workaround because I couldn't figure out how to make the compiler
+    /// accept non-initializing the value for the first pass of a for loop in 
+    /// `parse_header()`
+    fn new() -> Header {
+        Header { record: None, signal_specs: vec![] }
+    }
+
+    fn from_record(record: Record) -> Header {
+        Header { record: Some(record), signal_specs: vec![] }
+    }
+
+    fn add_signal_spec(&mut self, spec: SignalSpec) {
+        self.signal_specs.push(spec);
+    }
+
+    pub fn is_empty(&self) -> bool {
+        match self.record {
+            Some(_) => false,
+            None => true
+        }
+    }
+}
+
+/// Attempts to parse the header file
+pub fn parse_header(header_data: &str) -> Result<Header, &str> {
+    let header_lines: Vec<&str> = header_data.split("\n").collect();
+    let mut found_record: bool = false;
+    let mut header: Header = Header::new();
+    let mut specs_read: u64 = 0;
+    let mut specs_max: u64 = 0;
+    for line in header_lines {
+        // Ignore commented lines
+        if line.starts_with("#") {
+            continue;
+        }
+
+        if !found_record {
+            let possible_record = Record::from_str(line);
+            match possible_record {
+                Ok(rec) => {
+                    specs_max = rec.signal_count;
+                    header = Header::from_record(rec);
+                    found_record = true;
+                    continue;
+                }
+                Err(e) => {
+                    return Err(e)
+                }
+            }
+        }
+
+        let possible_spec = SignalSpec::from_str(line);
+        match possible_spec {
+            Ok(spec) => {
+               header.add_signal_spec(spec);
+            }
+            Err(e) => {
+                return Err(e);
+            }
+        }
+
+        specs_read += 1;
+        if specs_read >= specs_max {
+            break;
+        }
+    }
+
+    if header.is_empty() {
+        return Err("Unable to parse valid header information");
+    }
+    Ok(header)
+}

src/main.rs

@@ -1,3 +1,47 @@
-fn main() {
+use std::{env::{self}, io::Error, path::Path};
-    println!("Hello, world!");
+use std::fs;
+
+pub mod headproc; // The HEAder PROCessing 
+
+/// Use for handling possible formats of the WFDB data
+#[derive(Debug, Clone, Copy)]
+enum SignalFormat {
+    Format16 = 16,
+    Format212 = 212,
+    Unimpl = 0
 }
+
+fn main() -> Result<(), Error>{
+    let args: Vec<String> = env::args().collect();
+
+    if args.len() <= 1 || args.contains(&"help".to_string()) {
+        help();
+        return Ok(());
+    }
+
+    let filepath = Path::new(&args[1]);
+    if !filepath.is_file() {
+        println!("Path argument provided is not a valid file");
+        return Ok(());
+    }
+    if filepath.extension().unwrap() != "hea" {
+        println!("File provided is not a .hea file");
+        return Ok(());
+    }
+
+    let hea_file_result = fs::read_to_string(filepath);
+    match hea_file_result {
+        Ok(file_data) => {
+            let header = headproc::parse_header(file_data.as_str());
+            dbg!(header);
+        }
+        Err(e) => return Err(e)
+    }
+    println!("Hello, world!");
+    Ok(())
+}
+
+fn help() {
+    println!("Conversion of WFDB files to a more human readable format. By default to a CSV.");
+    println!("\nUse in the format \"wfdb_corrosion (.hea filename)\"")
+}