Add examples/guess_a_number_bot

.gitignore

@@ -7,4 +7,4 @@ examples/ping_pong_bot/target
 examples/dialogue_bot/target
 examples/multiple_handlers_bot/target
 examples/admin_bot/target
-examples/guess_a_number_bot
+examples/guess_a_number_bot/target

examples/guess_a_number_bot/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "guess_a_number_bot"
+version = "0.1.0"
+authors = ["Temirkhan Myrzamadi <hirrolot@gmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+log = "0.4.8"
+tokio = "0.2.9"
+smart-default = "0.6.0"
+rand = "0.7.3"
+pretty_env_logger = "0.4.0"
+teloxide = { path = "../../" }

examples/guess_a_number_bot/src/main.rs

@@ -0,0 +1,112 @@
+// This is a guess-a-number game!
+//
+// # Example
+// ```
+//  - Hello
+//  - Let's play a game! Guess a number from 1 to 10 (inclusively).
+//  - 4
+//  - No.
+//  - 3
+//  - No.
+//  - Blablabla
+//  - Oh, please, send me a text message!
+//  - 111
+//  - Oh, please, send me a number in the range [1; 10]!
+//  - 5
+//  - Congratulations! You won!
+// ```
+
+#[macro_use]
+extern crate smart_default;
+
+use teloxide::prelude::*;
+
+use rand::{thread_rng, Rng};
+
+// ============================================================================
+// [A type-safe finite automaton]
+// ============================================================================
+
+#[derive(SmartDefault)]
+enum Dialogue {
+    #[default]
+    Start,
+    ReceiveAttempt(u8),
+}
+
+// ============================================================================
+// [Control a dialogue]
+// ============================================================================
+
+async fn handle_message(
+    ctx: DialogueHandlerCtx<Message, Dialogue>,
+) -> Result<DialogueStage<Dialogue>, RequestError> {
+    match ctx.dialogue {
+        Dialogue::Start => {
+            ctx.answer(
+                "Let's play a game! Guess a number from 1 to 10 (inclusively).",
+            )
+            .send()
+            .await?;
+            next(Dialogue::ReceiveAttempt(thread_rng().gen_range(1, 11)))
+        }
+        Dialogue::ReceiveAttempt(secret) => match ctx.update.text() {
+            None => {
+                ctx.answer("Oh, please, send me a text message!")
+                    .send()
+                    .await?;
+                next(ctx.dialogue)
+            }
+            Some(text) => match text.parse::<u8>() {
+                Ok(attempt) => match attempt {
+                    x if !(1..=10).contains(&x) => {
+                        ctx.answer(
+                            "Oh, please, send me a number in the range [1; \
+                             10]!",
+                        )
+                        .send()
+                        .await?;
+                        next(ctx.dialogue)
+                    }
+                    x if x == secret => {
+                        ctx.answer("Congratulations! You won!").send().await?;
+                        exit()
+                    }
+                    _ => {
+                        ctx.answer("No.").send().await?;
+                        next(ctx.dialogue)
+                    }
+                },
+                Err(_) => {
+                    ctx.answer("Oh, please, send me a number!").send().await?;
+                    next(ctx.dialogue)
+                }
+            },
+        },
+    }
+}
+
+// ============================================================================
+// [Run!]
+// ============================================================================
+
+#[tokio::main]
+async fn main() {
+    run().await;
+}
+
+async fn run() {
+    teloxide::enable_logging!();
+    log::info!("Starting guess_a_number_bot!");
+
+    let bot = Bot::from_env();
+
+    Dispatcher::new(bot)
+        .message_handler(&DialogueDispatcher::new(|ctx| async move {
+            handle_message(ctx)
+                .await
+                .expect("Something wrong with the bot!")
+        }))
+        .dispatch()
+        .await;
+}