RCRPG/Rust

From Rosetta Code
RCRPG/Rust is part of RCRPG. You may find other members of RCRPG at Category:RCRPG.
Rust version of RCRPG.

Code[edit]

 
//! Implementation of the simple text-based game [RCRPG](https://web.archive.org/web/20080212201605/http://shortcircuit.us/muddy-kinda-like-a-mud-but-single-player/)
//! in Rust
 
use rand::prelude::*;
use std::borrow::BorrowMut;
use std::collections::{HashMap, HashSet};
use std::fmt::{Debug, Display};
use std::iter::FromIterator;
use std::ops::Add;
use std::{fmt, io};
 
/// Maps each Locations to a direction
const DIRECTION_MAPPING: [(Location, Direction); 6] = [
(Location(0, -1, 0), Direction::North),
(Location(0, 1, 0), Direction::South),
(Location(-1, 0, 0), Direction::West),
(Location(1, 0, 0), Direction::East),
(Location(0, 0, 1), Direction::Down),
(Location(0, 0, -1), Direction::Up),
];
 
/// Objects possessed by the player
type Inventory = HashSet<Object>;
/// Maps the (possibly user-defined) aliases to their actual action, so that for instance a player
/// can input either `n` or `north` to go North, and can also define new aliases
type CommandAliases = Vec<(HashSet<String>, Command)>;
 
/// 3D coordinates of objects in the dungeon
#[derive(Hash, Eq, PartialEq, Copy, Clone)]
struct Location(i32, i32, i32);
 
impl Add for Location {
type Output = Self;
 
fn add(self, rhs: Self) -> Self::Output {
Location(self.0 + rhs.0, self.1 + rhs.1, self.2 + rhs.2)
}
}
 
impl Debug for Location {
fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
write!(f, "({}, {}, {})", self.0, self.1, self.2)
}
}
 
/// Objects that can be found in the dungon rooms
#[derive(Eq, PartialEq, Hash, Copy, Clone, Debug)]
enum Object {
Ladder,
Sledge,
Gold,
}
 
impl Display for Object {
fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
match *self {
Object::Ladder => write!(f, "a ladder"),
Object::Sledge => write!(f, "a sledge"),
Object::Gold => write!(f, "some gold"),
}
}
}
 
impl Object {
/// Tries to parse a string to an object, like `"gold"` to `Object::Gold`
fn from_string(s: &str) -> Option<Object> {
match s {
"ladder" => Some(Object::Ladder),
"sledge" => Some(Object::Sledge),
"gold" => Some(Object::Gold),
_ => None,
}
}
}
 
/// Player information
struct Player {
/// Room where the player currently is
location: Location,
/// The objects carried by the player
inventory: Inventory,
/// The object wieled by the player, if any
equipped: Option<Object>,
}
 
/// Information about each room of the dungeon
struct Room {
/// Fixed description for special rooms (like the first one or the prize room)
description: Option<String>,
/// Objects currently in the room
objects: Inventory,
}
 
impl Room {
fn new() -> Self {
Room {
description: None,
objects: HashSet::new(),
}
}
 
/// Sets the room description
fn with_description(mut self, description: &str) -> Self {
self.description = Some(description.to_string());
self
}
 
/// Sets the objects in the room
fn with_objects(mut self, objects: Vec<Object>) -> Self {
self.objects.extend(objects);
self
}
 
/// Adds some randoms objects to the room
fn with_random_objects(mut self, rng: &mut ThreadRng) -> Self {
let objects: Vec<_> = vec![
if rng.gen::<f32>() < 0.33 {
Some(Object::Sledge)
} else {
None
},
if rng.gen::<f32>() < 0.33 {
Some(Object::Ladder)
} else {
None
},
if rng.gen::<f32>() < 0.33 {
Some(Object::Gold)
} else {
None
},
]
.iter()
.filter_map(|o| *o)
.collect();
 
self.objects.extend(objects);
self
}
}
 
/// Cardinat directions
#[derive(Copy, Clone, Eq, PartialEq)]
enum Direction {
North,
South,
West,
East,
Down,
Up,
}
 
impl Display for Direction {
fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
match *self {
Direction::North => write!(f, "north"),
Direction::South => write!(f, "south"),
Direction::West => write!(f, "west"),
Direction::East => write!(f, "east"),
Direction::Down => write!(f, "down"),
Direction::Up => write!(f, "up"),
}
}
}
 
impl Direction {
/// Tries to parse a string to a direction, like `"north"` to `Direction::North`
fn from_string(s: &str) -> Option<Direction> {
match s {
"north" => Some(Direction::North),
"south" => Some(Direction::South),
"west" => Some(Direction::West),
"east" => Some(Direction::East),
"down" => Some(Direction::Down),
"up" => Some(Direction::Up),
_ => None,
}
}
 
/// Returns the normalized 3D point of the location, for instance `Direction::North` is
/// `(0, -1, 0)` where `(x, y, z)`
fn to_location(self) -> Location {
DIRECTION_MAPPING.iter().find(|d| d.1 == self).unwrap().0
}
}
 
/// Collection of rooms
struct Dungeon {
/// The rooms that make up the dungeon
rooms: HashMap<Location, Room>,
}
 
impl Dungeon {
fn new() -> Self {
Dungeon {
rooms: HashMap::from_iter(vec![
(
Location(0, 0, 0),
Room::new()
.with_description("The room where it all started...")
.with_objects(vec![Object::Ladder, Object::Sledge]),
),
(
Location(1, 1, 5),
Room::new().with_description("You found it! Lots of gold!"),
),
]),
}
}
 
/// Given a room location, returns the list of `Direction`s that lead to other rooms
fn exits_for_room(&self, location: Location) -> Vec<Direction> {
DIRECTION_MAPPING
.iter()
.filter_map(|d| {
let location_to_test = location + d.0;
 
if self.rooms.contains_key(&location_to_test) {
return Some(d.1);
}
None
})
.collect()
}
}
 
/// Collection of all the available commands to interact to the dungeon world
#[derive(Debug, Copy, Clone)]
enum Command {
North,
South,
West,
East,
Down,
Up,
Help,
Dig,
Look,
Inventory,
Take,
Drop,
Equip,
Unequip,
Alias,
}
 
/// Returns the list of all the default command aliases
fn default_aliases() -> CommandAliases {
vec![
(
vec!["n".to_string(), "north".to_string()]
.into_iter()
.collect(),
Command::North,
),
(
vec!["s".to_string(), "south".to_string()]
.into_iter()
.collect(),
Command::South,
),
(
vec!["w".to_string(), "west".to_string()]
.into_iter()
.collect(),
Command::West,
),
(
vec!["e".to_string(), "east".to_string()]
.into_iter()
.collect(),
Command::East,
),
(
vec!["d".to_string(), "down".to_string()]
.into_iter()
.collect(),
Command::Down,
),
(
vec!["u".to_string(), "up".to_string()]
.into_iter()
.collect(),
Command::Up,
),
(
vec!["help".to_string()].into_iter().collect(),
Command::Help,
),
(vec!["dig".to_string()].into_iter().collect(), Command::Dig),
(
vec!["l".to_string(), "look".to_string()]
.into_iter()
.collect(),
Command::Look,
),
(
vec!["i".to_string(), "inventory".to_string()]
.into_iter()
.collect(),
Command::Inventory,
),
(
vec!["take".to_string()].into_iter().collect(),
Command::Take,
),
(
vec!["drop".to_string()].into_iter().collect(),
Command::Drop,
),
(
vec!["equip".to_string()].into_iter().collect(),
Command::Equip,
),
(
vec!["unequip".to_string()].into_iter().collect(),
Command::Unequip,
),
(
vec!["alias".to_string()].into_iter().collect(),
Command::Alias,
),
]
}
 
/// Tries to parse a string to a command also taking into account the aliases
fn find_command(command: &str, aliases: &[(HashSet<String>, Command)]) -> Option<Command> {
let command = command.to_lowercase();
 
aliases.iter().find(|a| a.0.contains(&command)).map(|a| a.1)
}
 
/// Prints the help string
fn help() {
println!(
"You need a sledge to dig rooms and ladders to go upwards.
Valid commands are: directions (north, south...), dig, take, drop, equip, inventory and look.
Additionally you can tag rooms with the 'name' command and alias commands with 'alias'.
Have fun!"
)
}
 
/// Defines a new alias for a command
fn alias(command_aliases: &mut CommandAliases, args: &[&str]) {
if args.len() < 2 {
println!("To assign an alias: alias CMQ NEW_ALIAS");
} else {
let command = args[0].to_lowercase();
let new_alias = args[1].to_lowercase();
 
let mut found = false;
for ca in command_aliases {
if ca.0.contains(&command) {
ca.0.insert(new_alias.clone());
found = true;
}
}
 
if found {
println!("You can use \"{}\" in lieu of \"{}\"", new_alias, command);
} else {
println!("The commands \"{}\" does not exist", command);
}
}
}
 
/// Describes the current rooom
fn look(player: &Player, dungeon: &Dungeon) {
let room = &dungeon.rooms[&player.location];
 
if let Some(description) = &room.description {
print!("{}", description);
} else {
print!("Room at {:?}.", player.location);
}
 
if !room.objects.is_empty() {
print!(
" On the floor you can see: {}.",
room.objects
.iter()
.map(|o| o.to_string())
.collect::<Vec<String>>()
.join(", ")
);
}
 
let room_exits = dungeon.exits_for_room(player.location);
match room_exits.len() {
0 => println!(" There are no exits in this room."),
1 => println!(" There is one exit: {}.", room_exits[0].to_string()),
_ => println!(
" Exits: {}.",
room_exits
.iter()
.map(|o| o.to_string())
.collect::<Vec<String>>()
.join(", ")
),
}
}
 
/// Grabs an object lying on the floor of a room and puts it into the player's inventory
fn take(player: &mut Player, dungeon: &mut Dungeon, args: &[&str]) {
if args.is_empty() {
println!("To take something: take OBJECT|all")
} else if dungeon.rooms[&player.location].objects.is_empty() {
println!("There is nothing to take here")
} else if args[0] == "all" {
let room_objects = dungeon
.rooms
.get_mut(&player.location)
.expect("The player is in a room that should not exist!")
.objects
.borrow_mut();
 
player.inventory.extend(room_objects.iter());
room_objects.clear();
 
println!("All items taken");
} else if let Some(object) = Object::from_string(args[0]) {
let room_objects = dungeon
.rooms
.get_mut(&player.location)
.expect("The player is in a room that should not exist!")
.objects
.borrow_mut();
 
if room_objects.contains(&object) {
player.inventory.insert(object);
room_objects.remove(&object);
println!("Taken");
}
} else {
println!("You can't see anything like that here")
}
}
 
/// Removes an object from the player's inventory and leaves it lying on the current room's floor
fn drop(player: &mut Player, dungeon: &mut Dungeon, args: &[&str]) {
if args.is_empty() {
println!("To drop something: drop OBJECT|all")
} else if player.inventory.is_empty() {
println!("You are not carrying anything")
} else if args[0] == "all" {
let room_objects = dungeon
.rooms
.get_mut(&player.location)
.expect("The player is in a room that should not exist!")
.objects
.borrow_mut();
 
room_objects.extend(player.inventory.iter());
player.inventory.clear();
 
println!("All items dropped");
} else if let Some(object) = Object::from_string(args[0]) {
let room_objects = dungeon
.rooms
.get_mut(&player.location)
.expect("The player is in a room that should not exist!")
.objects
.borrow_mut();
 
if player.inventory.contains(&object) {
player.inventory.remove(&object);
room_objects.insert(object);
println!("Dropped");
}
} else {
println!("You don't have anything like that")
}
}
 
/// Prints the list of object currently carries by the player
fn inventory(player: &Player) {
if player.inventory.is_empty() {
println!("You are not carrying anything")
} else {
println!(
"You are carrying: {}",
player
.inventory
.iter()
.map(|o| o.to_string())
.collect::<Vec<String>>()
.join(", ")
);
}
}
 
/// Digs a tunnel to a new room connected to the current one
#[allow(clippy::map_entry)]
fn dig(player: &Player, dungeon: &mut Dungeon, rng: &mut ThreadRng, args: &[&str]) {
if args.is_empty() {
println!("To dig a tunnel: dig DIRECTION");
} else if let Some(direction) = Direction::from_string(args[0]) {
if let Some(equipped) = player.equipped {
if equipped == Object::Sledge {
let target_location = player.location + direction.to_location();
 
if dungeon.rooms.contains_key(&target_location) {
println!("There is already an exit, there!");
}
 
dungeon.rooms.entry(target_location).or_insert_with(|| {
println!("There is now an exit {}ward", direction);
 
Room::new().with_random_objects(rng)
});
} else {
println!("You cannot dig with {}", equipped);
}
} else {
println!("With your bare hands?");
}
} else {
println!("That is not a direction I recognize");
}
}
 
/// Moves the player to an adjacent room
fn goto(player: &mut Player, dungeon: &Dungeon, direction: Direction) {
if direction == Direction::North
&& !dungeon.rooms[&player.location]
.objects
.contains(&Object::Ladder)
{
println!("You can't go upwards without a ladder!");
} else {
let target_location = player.location + direction.to_location();
if !dungeon.rooms.contains_key(&target_location) {
println!("There's no exit in that direction!");
} else {
player.location = target_location;
look(player, dungeon);
}
}
}
 
/// Equips an object
fn equip(player: &mut Player, args: &[&str]) {
if args.is_empty() {
println!("To equip something: equip OBJECT");
} else if let Some(object) = Object::from_string(args[0]) {
if player.inventory.contains(&object) {
player.equipped = Some(object);
println!("Item equipped");
} else {
println!("You don't have such object");
}
} else {
println!("You don't have such object");
}
}
 
/// Unequips an object
fn unequip(player: &mut Player) {
if player.equipped.is_some() {
player.equipped = None;
println!("Unequipped");
} else {
println!("You are already not using anything");
}
}
 
/// Main game loop
fn main() {
let mut command_aliases = default_aliases();
let mut dungeon = Dungeon::new();
let mut player = Player {
location: Location(0, 0, 0),
inventory: HashSet::from_iter(vec![Object::Sledge]),
equipped: None,
};
let mut rng = rand::thread_rng();
 
// init
println!("Grab the sledge and make your way to room 1,1,5 for a non-existant prize!\n");
help();
 
loop {
let mut input = String::new();
io::stdin()
.read_line(&mut input)
.expect("Cannot read from stdin");
let input: &str = &input.trim().to_lowercase();
 
let splitted = input.split_whitespace().collect::<Vec<&str>>();
 
if !splitted.is_empty() {
match find_command(splitted[0], &command_aliases) {
Some(Command::Help) => help(),
Some(Command::Alias) => alias(&mut command_aliases, &splitted[1..]),
Some(Command::Look) => look(&player, &dungeon),
Some(Command::Take) => take(&mut player, &mut dungeon, &splitted[1..]),
Some(Command::Drop) => drop(&mut player, &mut dungeon, &splitted[1..]),
Some(Command::Inventory) => inventory(&player),
Some(Command::Dig) => dig(&player, &mut dungeon, &mut rng, &splitted[1..]),
Some(Command::Equip) => equip(&mut player, &splitted[1..]),
Some(Command::Unequip) => unequip(&mut player),
Some(Command::North) => goto(&mut player, &dungeon, Direction::North),
Some(Command::South) => goto(&mut player, &dungeon, Direction::South),
Some(Command::West) => goto(&mut player, &dungeon, Direction::West),
Some(Command::East) => goto(&mut player, &dungeon, Direction::East),
Some(Command::Down) => goto(&mut player, &dungeon, Direction::Down),
Some(Command::Up) => goto(&mut player, &dungeon, Direction::Up),
_ => println!("I don't know what you mean."),
}
}
}
}