example/
example.rs

1use std::{
2    collections::HashMap,
3    fs::File,
4    io::{self, BufRead, BufReader, Read, Write},
5    path::Path,
6    process::ExitCode,
7    str::FromStr,
8};
9
10use petri_nets::{FireDirection, FireState, SimulatedNet, Simulation, SimulationStateMut};
11use pns::{Net, Tid};
12
13fn main() -> ExitCode {
14    let mut save = false;
15    let mut load = false;
16
17    let mut args = std::env::args();
18    args.next();
19    for arg in args {
20        match arg.as_ref() {
21            "save" => save = true,
22            "load" => load = true,
23            _ => eprintln!("Ignore invalid argument '{arg}'"),
24        }
25    }
26
27    let Ok(net) = Net::load("examples/example.pn".as_ref()) else {
28        eprintln!("Failed to load example net");
29        return ExitCode::FAILURE;
30    };
31    let mut net = SimulatedNet::new(net);
32
33    let mut names = HashMap::new();
34    let Ok(file) = File::open("examples/example.pnk") else {
35        eprintln!("Failed to load example keys");
36        return ExitCode::FAILURE;
37    };
38    for (tid, line) in net.transition_ids().zip(BufReader::new(file).lines()) {
39        let Ok(line) = line else {
40            eprintln!("Failed to read key");
41            return ExitCode::FAILURE;
42        };
43        names.insert(tid, line);
44    }
45
46    if save && net.save("examples/example_copy.pns".as_ref()).is_err() {
47        eprintln!("Failed to save example net");
48    }
49
50    if load {
51        fn read_values(filename: &Path) -> std::io::Result<Vec<u32>> {
52            let size = (std::fs::metadata(filename)?.len() + 3) / 4;
53
54            let mut file = File::open(filename)?;
55
56            (0..size)
57                .map(|_| {
58                    let mut value = [0; 4];
59                    file.read_exact(&mut value)?;
60                    Ok(u32::from_le_bytes(value))
61                })
62                .collect()
63        }
64
65        let Ok(data) = read_values("examples/example.pns".as_ref()) else {
66            eprintln!("Reading state data failed");
67            return ExitCode::FAILURE;
68        };
69
70        if net.add_simulation_from_data(data).is_err() {
71            eprintln!("State initialization failed");
72            return ExitCode::FAILURE;
73        }
74    } else {
75        net.add_simulation();
76    }
77
78    enum StepAction {
79        Continue,
80        Reverse,
81        Save,
82        Quit,
83    }
84
85    let mut forward = true;
86    for mut simulation in &mut net {
87        fn step<D: FireDirection>(
88            fire: FireState<SimulationStateMut, D>,
89            names: &HashMap<Tid, String>,
90        ) -> StepAction {
91            if fire.callables.is_empty() {
92                return StepAction::Reverse;
93            }
94
95            for (i, tid) in fire.callables.iter().enumerate() {
96                println!("{}: {}", i + 1, names[tid]);
97            }
98            let stdin = io::stdin();
99            let mut string = String::new();
100            let Ok(size) = stdin.read_line(&mut string) else {
101                eprintln!("Input error");
102                return StepAction::Continue;
103            };
104            if size == 0 {
105                return StepAction::Continue;
106            }
107            match unsafe { string.chars().next().unwrap_unchecked() } {
108                'r' => return StepAction::Reverse,
109                'q' => return StepAction::Quit,
110                's' => return StepAction::Save,
111                _ => (),
112            }
113            match usize::from_str(&string[..(string.len() - 1)]) {
114                Ok(num) if num != 0 && num <= fire.callables.len() => {
115                    fire.call(num - 1);
116                }
117                _ => {
118                    println!(
119                        "You have to input a valid number from 1 to {}",
120                        fire.callables.len()
121                    );
122                    println!("You can also quit by writing \"q\", save the current state by writing \"s\" or reverse by writing \"r\"");
123                    return StepAction::Continue;
124                }
125            }
126
127            StepAction::Continue
128        }
129
130        loop {
131            let step_action = if forward {
132                step(simulation.prepare_call(), &names)
133            } else {
134                step(simulation.prepare_revert(), &names)
135            };
136
137            use StepAction::*;
138            match step_action {
139                Continue => (),
140                Reverse => {
141                    println!("Reverse play direction!");
142                    forward = !forward;
143                }
144                Save => {
145                    fn save(data: &[usize], filename: &Path) -> std::io::Result<()> {
146                        let mut file = File::create(filename)?;
147                        for &count in data {
148                            file.write_all(&(count as u32).to_le_bytes())?;
149                        }
150
151                        Ok(())
152                    }
153
154                    let data = simulation.data();
155
156                    println!(
157                        "{}",
158                        if save(data, "examples/example.pns".as_ref()).is_ok() {
159                            "Saving successful"
160                        } else {
161                            "Saving failed"
162                        }
163                    );
164                }
165                Quit => break,
166            }
167        }
168    }
169
170    ExitCode::SUCCESS
171}
example/example.rs

example/
example.rs
