Improves the handling of Header::from_record

The correct vector capacity is now automatically initialized

.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/headparse.rs

@@ -0,0 +1,481 @@
+use std::{collections::HashMap, u64, vec};
+
+use crate::SignalFormat;
+
+/// Holds the essential header information about the record, like the amount of
+/// signals, and the sampling frequency.
+/// 
+/// 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: usize,
+    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 of the argument 
+    /// line that's provided by the WFDB header file
+    /// 
+    /// Returns a `Result<Record, &str>`, with the error field potentially
+    /// describing why the parsing operation failed
+    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: usize;
+        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 mut base_counter_val: Option<u64> = None;
+        let mut sample_num: Option<u64> = None;
+        let mut basetime: Option<String> = None;
+        let mut 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::<usize>() {
+                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.");
+                    }
+                }
+            }
+
+            if args.len() <= 3 {break;}
+
+            match args[3].parse::<u64>() {
+                Ok(value) => {
+                    base_counter_val = Some(value);
+                }
+                Err(_) => {}
+            }
+            
+            if args.len() <= 4 {break;}
+
+            match args[4].parse::<u64>() {
+                Ok(value) => {
+                    sample_num = Some(value);
+                }
+                Err(_) => {}
+            }
+
+            if args.len() <= 5 {break;}
+
+            basetime = Some(args[5].to_string());
+
+            if args.len() <= 6 {break;}
+
+            basedate = Some(args[6].to_string());
+
+            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 
+        })
+    }
+}
+
+/// Keys for all the data that can possibly be parsed from the values appended 
+/// to the ADC block
+#[derive(Debug, Eq, Hash, PartialEq)]
+enum AdcBlockKeys {
+    Gain,
+    Baseline,
+    Units
+}
+
+/// Holds the information relevant to individual signals and their specifications
+/// 
+/// By minimum, only carries the `filename`, `format`, and `adc_zero` attributes
+#[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<i64>,
+    units: Option<String>,
+    adc_resolution: Option<u64>,
+    adc_zero: i64,
+    initial_val: Option<i64>,
+    checksum: Option<i64>,
+    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
+    /// relevant to parsing failures.
+    /// 
+    /// ## 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 mut adc_gain: Option<f64> = None;
+        let mut baseline: Option<i64> = None;
+        let mut units: Option<String> = None;
+        let mut adc_resolution: Option<u64> = None;
+        let mut adc_zero:i64 = 0;
+        let mut initial_val: Option<i64> = None;
+        let mut checksum: Option<i64> = None;
+        let mut blocksize: Option<u64> = None;
+        let mut desc: Option<String> = None;
+
+        // TODO: implement samplesperframe, skew, and offset
+        match args[1].parse::<u64>() {
+            Ok(value) => {
+                sigformat = SignalSpec::parse_format(value);
+            },
+            Err(_) => {
+                return Err("error: unable to parse format from signal");
+            } 
+        }
+
+        loop {
+            if args.len() <= 2 {
+                break;
+            }
+
+            {
+                let mut results: HashMap<AdcBlockKeys, String> = HashMap::new();
+                let mut buffer: String = String::new();
+                let mut found_baseline = false;
+                let mut found_units = false;
+
+                // Parse through all the characters and get the individual parts
+                for character in args[2].chars() {
+                    loop {
+                        if !found_baseline && !found_units && character == '(' {
+                            found_baseline = true;
+                            results.insert(AdcBlockKeys::Gain, buffer);
+                            buffer = String::new();
+                            break;
+                        }
+                        else if found_baseline && character == ')' {
+                            results.insert(AdcBlockKeys::Baseline, buffer);
+                            buffer = String::new();
+                            break;
+                        }
+                        else if !found_units && character == '/' {
+                            found_units = true;
+                            if !found_baseline {
+                                results.insert(AdcBlockKeys::Gain, buffer);
+                            }
+                            buffer = String::new();
+                            break;
+                        }
+                        buffer.push(character);
+                        break;
+                    }
+                }
+                if found_units {
+                    results.insert(AdcBlockKeys::Units, buffer);
+                }
+                
+                // Try and get the actual values out of the results
+                match results.get(&AdcBlockKeys::Gain) {
+                    Some(value ) => {
+                        match value.parse::<f64>() {
+                            Ok(parsed) => {
+                                adc_gain = Some(parsed);
+                            },
+                            Err(_) => {
+                                return Err("error: Signal contains adc gain block with invalid entry");
+                            }
+                        }
+                    },
+                    None => {
+                        return Err("error: Signal contains adc gain block but the block is empty.");
+                    }
+                }
+
+                match results.get(&AdcBlockKeys::Baseline) {
+                    Some(value) => {
+                        match value.parse::<i64>() {
+                            Ok(parsed) => {
+                                baseline = Some(parsed);
+                            },
+                            Err(_) => {
+                                return Err("error: Unable to parse baseline from signal");
+                            }
+                        }
+                    },
+                    None => {}
+                }
+                match results.get(&AdcBlockKeys::Units) {
+                    Some(value) => {
+                        units = Some(value.clone());
+                    },
+                    None => {}
+                }
+            }
+            
+            if args.len() <= 3 {
+                break;
+            }
+            match args[3].parse::<u64>() {
+                Ok(value) => {
+                    adc_resolution = Some(value);
+                },
+                Err(_) => {
+                    return Err("error: unable to parse resolution from signal");
+                } 
+            }
+
+            if args.len() <= 4 {
+                break;
+            }
+            match args[4].parse::<i64>() {
+                Ok(value) => {
+                    adc_zero = value;
+                },
+                Err(_) => {
+                    adc_zero = 0; // Standard: If this field is missing, a value of zero is assumed.
+                } 
+            }
+
+            if args.len() <= 5 {
+                break;
+            }
+            match args[5].parse::<i64>() {
+                Ok(value) => {
+                    initial_val = Some(value);
+                },
+                // Standard: If this field is missing, 
+                // the adc_zero value is presumed.
+                // We do this on the data parsing part.
+                Err(_) => {} 
+            }
+
+            if args.len() <= 6 {
+                break;
+            }
+            match args[6].parse::<i64>() {
+                Ok(value) => {
+                   checksum = Some(value);
+                },
+                Err(_) => {
+                    return Err("error: unable to parse checksum from signal");
+                } 
+            }
+
+            if args.len() <= 7 {
+                break;
+            }
+            match args[7].parse::<u64>() {
+                Ok(value) => {
+                    blocksize = Some(value);
+                },
+                Err(_) => {
+                    return Err("error: unable to parse block size from signal");
+                } 
+            }
+
+            if args.len() <= 8 {
+                break;
+            }
+            desc = Some(args[8].to_string());
+
+            break;
+        }
+        
+        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 }
+        )
+    }
+
+    /// Parses the WFDB signal format from the format number, if it exists and
+    /// is implemented
+    fn parse_format(formatnum: u64) -> SignalFormat {
+        match formatnum {
+            16 => SignalFormat::Format16,
+            212 => SignalFormat::Format212,
+            0..=u64::MAX => SignalFormat::Unimpl
+        }
+    }
+}
+
+/// Holds all the possible data from the WFDB header file, those being the record
+/// line data and all the possible signal specifications present on the following
+/// lines
+#[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![] }
+    }
+
+    /// Creates a Header from a supplied Record struct. 
+    /// 
+    /// Initializes the signal_specs vector with the correct capacity provided
+    /// by the record.
+    fn from_record(record: Record) -> Header {
+        let capacity = record.signal_count;
+        Header { record: Some(record), signal_specs: Vec::with_capacity(capacity) }
+    }
+
+    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. 
+/// 
+/// Returns a Result either containing the `Header` struct, or the
+/// error string describing why we couldn't parse the header.
+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: usize = 0;
+    let mut specs_max: usize = 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() {
-    println!("Hello, world!");
+use std::{env::{self}, io::Error, path::Path};
+use std::fs;
+
+pub mod headparse; // The HEAder parsing 
+
+/// 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 = headparse::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)\"")
+}