Day 4 WIP parsing lines

Cargo.lock

@@ -2,6 +2,7 @@
 name = "advent-of-code-2018"
 version = "0.1.0"
 dependencies = [
+ "chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -18,6 +19,16 @@ name = "cfg-if"
 version = "0.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "chrono"
+version = "0.4.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "num-integer 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-traits 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "time 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "lazy_static"
 version = "1.2.0"
@@ -38,6 +49,24 @@ dependencies = [
  "version_check 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "num-integer"
+version = "0.1.39"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "num-traits 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "num-traits"
+version = "0.2.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "redox_syscall"
+version = "0.1.44"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "regex"
 version = "1.1.0"
@@ -66,6 +95,16 @@ dependencies = [
  "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "time"
+version = "0.1.41"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)",
+ "redox_syscall 0.1.44 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "ucd-util"
 version = "0.1.3"
@@ -81,15 +120,42 @@ name = "version_check"
 version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "winapi"
+version = "0.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "winapi-i686-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi-x86_64-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [metadata]
 "checksum aho-corasick 0.6.9 (registry+https://github.com/rust-lang/crates.io-index)" = "1e9a933f4e58658d7b12defcf96dc5c720f20832deebe3e0a19efd3b6aaeeb9e"
 "checksum cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "082bb9b28e00d3c9d39cc03e64ce4cea0f1bb9b3fde493f0cbc008472d22bdf4"
+"checksum chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "45912881121cb26fad7c38c17ba7daa18764771836b34fab7d3fbd93ed633878"
 "checksum lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a374c89b9db55895453a74c1e38861d9deec0b01b405a82516e9d5de4820dea1"
 "checksum libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)" = "2d2857ec59fadc0773853c664d2d18e7198e83883e7060b63c924cb077bd5c74"
 "checksum memchr 2.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "db4c41318937f6e76648f42826b1d9ade5c09cafb5aef7e351240a70f39206e9"
+"checksum num-integer 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)" = "e83d528d2677f0518c570baf2b7abdcf0cd2d248860b68507bdcb3e91d4c0cea"
+"checksum num-traits 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "0b3a5d7cc97d6d30d8b9bc8fa19bf45349ffe46241e8816f50f62f6d6aaabee1"
+"checksum redox_syscall 0.1.44 (registry+https://github.com/rust-lang/crates.io-index)" = "a84bcd297b87a545980a2d25a0beb72a1f490c31f0a9fde52fca35bfbb1ceb70"
 "checksum regex 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "37e7cbbd370869ce2e8dff25c7018702d10b21a20ef7135316f8daecd6c25b7f"
 "checksum regex-syntax 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)" = "4e47a2ed29da7a9e1960e1639e7a982e6edc6d49be308a3b02daf511504a16d1"
 "checksum thread_local 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "c6b53e329000edc2b34dbe8545fd20e55a333362d0a321909685a19bd28c3f1b"
+"checksum time 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)" = "847da467bf0db05882a9e2375934a8a55cffdc9db0d128af1518200260ba1f6c"
 "checksum ucd-util 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "535c204ee4d8434478593480b8f86ab45ec9aae0e83c568ca81abf0fd0e88f86"
 "checksum utf8-ranges 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "796f7e48bef87609f7ade7e06495a87d5cd06c7866e6a5cbfceffc558a243737"
 "checksum version_check 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "914b1a6776c4c929a602fafd8bc742e06365d4bcbe48c30f9cca5824f70dc9dd"
+"checksum winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "92c1eb33641e276cfa214a0522acad57be5c56b10cb348b3c5117db75f3ac4b0"
+"checksum winapi-i686-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+"checksum winapi-x86_64-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"

Cargo.toml

@@ -5,4 +5,5 @@ authors = ["Tyler Hallada <tyler@hallada.net>"]
 edition = "2018"
 
 [dependencies]
+chrono = "0.4"
 regex = "1"

inputs/4_test.txt

@@ -0,0 +1,17 @@
+[1518-11-01 00:00] Guard #10 begins shift
+[1518-11-01 00:05] falls asleep
+[1518-11-01 00:25] wakes up
+[1518-11-01 00:30] falls asleep
+[1518-11-01 00:55] wakes up
+[1518-11-01 23:58] Guard #99 begins shift
+[1518-11-02 00:40] falls asleep
+[1518-11-02 00:50] wakes up
+[1518-11-03 00:05] Guard #10 begins shift
+[1518-11-03 00:24] falls asleep
+[1518-11-03 00:29] wakes up
+[1518-11-04 00:02] Guard #99 begins shift
+[1518-11-04 00:36] falls asleep
+[1518-11-04 00:46] wakes up
+[1518-11-05 00:03] Guard #99 begins shift
+[1518-11-05 00:45] falls asleep
+[1518-11-05 00:55] wakes up

inputs/4_test_malformed.txt

@@ -0,0 +1,5 @@
+[1518-11-01 00:00] Guard #10 begins shift
+[1518-11-01 00:05] falls asleep
+[1518-11-01 00:25] wakes up
+[1518-11-01 00:30] falls asleep
+[1518-11-01 00:55] dies

src/day4.rs

@@ -0,0 +1,206 @@
+extern crate chrono;
+extern crate regex;
+
+use std::error::Error;
+use std::fs::File;
+use std::io::{BufRead, BufReader};
+use std::fmt;
+use std::collections::{HashMap, HashSet};
+use std::iter::FromIterator;
+
+use chrono::prelude::*;
+use regex::{Regex, Captures};
+
+const INPUT: &str = "inputs/4.txt";
+
+#[derive(Debug, PartialEq)]
+enum Record {
+    Start {
+        time: NaiveDateTime,
+        guard_id: u32,
+    },
+    Sleep {
+        time: NaiveDateTime,
+    },
+    Wake {
+        time: NaiveDateTime,
+    },
+}
+
+#[derive(Debug, Clone, PartialEq)]
+struct MalformedRecord {
+    details: String
+}
+
+impl MalformedRecord {
+    fn new(msg: &str) -> MalformedRecord {
+        MalformedRecord{ details: msg.to_string() }
+    }
+}
+
+impl fmt::Display for MalformedRecord {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.details)
+    }
+}
+
+impl Error for MalformedRecord {
+    fn description(&self) -> &str {
+        &self.details
+    }
+}
+
+fn read_records(filename: &str) -> Result<Vec<Record>, Box<Error>> {
+    let mut records: Vec<Record> = Vec::new();
+    let record_regex =
+        Regex::new(r"\[(?P<timestamp>\d{4}-\d{2}-\d{2}\s\d{2}:\d{2})\]\s(?:(?P<start>Guard #(?P<guard_id>\d+) begins shift)|(?P<sleep>falls asleep)|(?P<wake>wakes up))")?;
+    let file = File::open(filename)?;
+    for line in BufReader::new(file).lines() {
+        match record_regex.captures(&line?) {
+            Some(captures) => {
+                println!("{:?}", NaiveDateTime::parse_from_str(
+                    &get_captured_field(&captures, "timestamp")?,
+                    "%Y-%m-%d %H:%M")?);
+                if has_captured_field(&captures, "start")? {
+                    records.push(Record::Start {
+                        time: NaiveDateTime::parse_from_str(
+                            &get_captured_field(&captures, "timestamp")?,
+                            "%Y-%m-%d %H:%M")?,
+                        guard_id: get_captured_field(&captures, "guard_id")?.parse()?,
+                    });
+                } else if has_captured_field(&captures, "sleep")? {
+                    records.push(Record::Sleep {
+                        time: NaiveDateTime::parse_from_str(
+                            &get_captured_field(&captures, "timestamp")?,
+                            "%Y-%m-%d %H:%M")?,
+                    });
+                } else {
+                    records.push(Record::Wake {
+                        time: NaiveDateTime::parse_from_str(
+                            &get_captured_field(&captures, "timestamp")?,
+                            "%Y-%m-%d %H:%M")?,
+                    });
+                }
+            },
+            None => return Err(Box::new(MalformedRecord {
+                details: "Malformed record line, no fields could be found".to_string()
+            })),
+        };
+    }
+    Ok(records)
+}
+
+fn get_captured_field(captures: &Captures, field: &str) -> Result<String, Box<Error>> {
+    match captures.name(field) {
+        Some(capture) => Ok(String::from(capture.as_str())),
+        None => return Err(Box::new(MalformedRecord {
+            details: format!("Malformed record line, field {} could not be found", field)
+        }))
+    }
+}
+
+fn has_captured_field(captures: &Captures, field: &str) -> Result<bool, Box<Error>> {
+    match captures.name(field) {
+        Some(_) => Ok(true),
+        None => Ok(false)
+    }
+}
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const TEST_INPUT: &str = "inputs/4_test.txt";
+    const TEST_INPUT_MALFORMED: &str = "inputs/4_test_malformed.txt";
+
+    #[test]
+    fn reads_records_file() {
+        assert_eq!(read_records(TEST_INPUT).unwrap(), vec![
+            Record::Start {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-01 00:00", "%Y-%m-%d %H:%M").unwrap(),
+                guard_id: 10,
+            },
+            Record::Sleep {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-01 00:05", "%Y-%m-%d %H:%M").unwrap(),
+            },
+            Record::Wake {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-01 00:25", "%Y-%m-%d %H:%M").unwrap(),
+            },
+            Record::Sleep {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-01 00:30", "%Y-%m-%d %H:%M").unwrap(),
+            },
+            Record::Wake {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-01 00:55", "%Y-%m-%d %H:%M").unwrap(),
+            },
+            Record::Start {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-01 23:58", "%Y-%m-%d %H:%M").unwrap(),
+                guard_id: 99,
+            },
+            Record::Sleep {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-02 00:40", "%Y-%m-%d %H:%M").unwrap(),
+            },
+            Record::Wake {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-02 00:50", "%Y-%m-%d %H:%M").unwrap(),
+            },
+            Record::Start {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-03 00:05", "%Y-%m-%d %H:%M").unwrap(),
+                guard_id: 10,
+            },
+            Record::Sleep {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-03 00:24", "%Y-%m-%d %H:%M").unwrap(),
+            },
+            Record::Wake {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-03 00:29", "%Y-%m-%d %H:%M").unwrap(),
+            },
+            Record::Start {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-04 00:02", "%Y-%m-%d %H:%M").unwrap(),
+                guard_id: 99,
+            },
+            Record::Sleep {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-04 00:36", "%Y-%m-%d %H:%M").unwrap(),
+            },
+            Record::Wake {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-04 00:46", "%Y-%m-%d %H:%M").unwrap(),
+            },
+            Record::Start {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-05 00:03", "%Y-%m-%d %H:%M").unwrap(),
+                guard_id: 99,
+            },
+            Record::Sleep {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-05 00:45", "%Y-%m-%d %H:%M").unwrap(),
+            },
+            Record::Wake {
+                time: NaiveDateTime::parse_from_str(
+                          "1518-11-05 00:55", "%Y-%m-%d %H:%M").unwrap(),
+            },
+        ]);
+    }
+
+    #[test]
+    fn errors_on_malformed_records_file() {
+        match read_records(TEST_INPUT_MALFORMED) {
+            Ok(_) => assert!(false, "read_records should have returned an error"),
+            Err(err) => assert_eq!(
+                (*err).description(),
+                "Malformed record line, no fields could be found".to_string(),
+            ),
+        }
+    }
+}

src/main.rs

@@ -1,6 +1,7 @@
 mod day1;
 mod day2;
 mod day3;
+mod day4;
 
 fn main() {
     println!("Day 1:");