7 files changed, 936 insertions, 0 deletions
diff --git a/corp/russian/predlozhnik/.gitignore b/corp/russian/predlozhnik/.gitignore
new file mode 100644
index 0000000000..58eaf3e326
--- /dev/null
+++ b/corp/russian/predlozhnik/.gitignore
@@ -0,0 +1,3 @@
+/target/
+**/*.rs.bk
+dist/
diff --git a/corp/russian/predlozhnik/Cargo.lock b/corp/russian/predlozhnik/Cargo.lock
new file mode 100644
index 0000000000..1cacb43b39
--- /dev/null
+++ b/corp/russian/predlozhnik/Cargo.lock
@@ -0,0 +1,471 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
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+ "gloo-dialogs",
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+ "gloo-file",
+ "gloo-render",
+ "gloo-storage",
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+ "gloo-utils",
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+ "serde",
+ "serde_json",
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+[[package]]
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+ "lazy_static",
+ "maplit",
+ "wasm-bindgen",
+ "yew",
+]
+
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+ "proc-macro-error-attr",
+ "proc-macro2",
+ "quote",
+ "syn 1.0.101",
+ "version_check",
+]
+
+[[package]]
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+]
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+ "wasm-bindgen-macro",
+]
+
+[[package]]
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+ "bumpalo",
+ "log",
+ "once_cell",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.28",
+ "wasm-bindgen-shared",
+]
+
+[[package]]
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+ "wasm-bindgen",
+ "web-sys",
+]
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+ "quote",
+ "syn 2.0.28",
+ "wasm-bindgen-backend",
+ "wasm-bindgen-shared",
+]
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+[[package]]
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+ "wasm-bindgen",
+]
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+checksum = "2a1ccb53e57d3f7d847338cf5758befa811cabe207df07f543c06f502f9998cd"
+dependencies = [
+ "console_error_panic_hook",
+ "gloo",
+ "gloo-utils",
+ "indexmap",
+ "js-sys",
+ "scoped-tls-hkt",
+ "slab",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+ "yew-macro",
+]
+
+[[package]]
+name = "yew-macro"
+version = "0.19.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5fab79082b556d768d6e21811869c761893f0450e1d550a67892b9bce303b7bb"
+dependencies = [
+ "boolinator",
+ "lazy_static",
+ "proc-macro-error",
+ "proc-macro2",
+ "quote",
+ "syn 1.0.101",
+]
diff --git a/corp/russian/predlozhnik/Cargo.toml b/corp/russian/predlozhnik/Cargo.toml
new file mode 100644
index 0000000000..87537b560b
--- /dev/null
+++ b/corp/russian/predlozhnik/Cargo.toml
@@ -0,0 +1,12 @@
+[package]
+name = "predlozhnik"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+maplit = "1.0"
+lazy_static = "1.4"
+yew = "0.19"
+
+# needs to be in sync with nixpkgs
+wasm-bindgen = "= 0.2.91"
diff --git a/corp/russian/predlozhnik/default.nix b/corp/russian/predlozhnik/default.nix
new file mode 100644
index 0000000000..2137be1112
--- /dev/null
+++ b/corp/russian/predlozhnik/default.nix
@@ -0,0 +1,52 @@
+{ lib, pkgs, ... }:
+
+let
+  wasmRust = pkgs.rust-bin.stable.latest.default.override {
+    targets = [ "wasm32-unknown-unknown" ];
+  };
+
+  cargoToml = with builtins; fromTOML (readFile ./Cargo.toml);
+
+  wasmBindgenMatch =
+    cargoToml.dependencies.wasm-bindgen == "= ${pkgs.wasm-bindgen-cli.version}";
+
+  assertWasmBindgen = assert (lib.assertMsg wasmBindgenMatch ''
+    Due to instability in the Rust WASM ecosystem, the trunk build
+    tool enforces that the Cargo-dependency version of `wasm-bindgen`
+    MUST match the version of the CLI supplied in the environment.
+
+    This can get out of sync when nixpkgs is updated. To resolve it,
+    wasm-bindgen must be bumped in the Cargo.toml file and cargo needs
+    to be run to resolve the dependencies.
+
+    Versions of `wasm-bindgen` in Cargo.toml:
+
+      Expected: '= ${pkgs.wasm-bindgen-cli.version}'
+      Actual:   '${cargoToml.dependencies.wasm-bindgen}'
+  ''); pkgs.wasm-bindgen-cli;
+
+  deps = with pkgs; [
+    binaryen
+    sass
+    wasmRust
+    trunk
+    assertWasmBindgen
+  ];
+
+in
+pkgs.rustPlatform.buildRustPackage rec {
+  pname = "predlozhnik";
+  version = "canon";
+  src = lib.cleanSource ./.;
+  cargoLock.lockFile = ./Cargo.lock;
+
+  buildPhase = ''
+    export PATH=${lib.makeBinPath deps}:$PATH
+    mkdir home
+    export HOME=$PWD/.home
+    env
+    trunk build --release -d $out
+  '';
+
+  dontInstall = true;
+}
diff --git a/corp/russian/predlozhnik/index.css b/corp/russian/predlozhnik/index.css
new file mode 100644
index 0000000000..3529574c4f
--- /dev/null
+++ b/corp/russian/predlozhnik/index.css
@@ -0,0 +1,29 @@
+body {
+    max-width: 800px;
+    margin: 40px auto;
+}
+
+#header {
+    display: flex;
+    flex-direction: column;
+}
+
+.btn.btn-ghost:disabled {
+    border-color: #9f9f9f;
+    color: #9f9f9f;
+}
+
+#predlogi,#padezhi {
+    display: flex;
+    flex-direction: row;
+    flex-wrap: wrap;
+}
+
+.btn {
+    margin: 3px;
+    flex-grow: 1;
+}
+
+.footer {
+    text-align: right;
+}
diff --git a/corp/russian/predlozhnik/index.html b/corp/russian/predlozhnik/index.html
new file mode 100644
index 0000000000..6af1adc0bf
--- /dev/null
+++ b/corp/russian/predlozhnik/index.html
@@ -0,0 +1,24 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <link rel="stylesheet"
+          href="https://unpkg.com/terminal.css@0.7.2/dist/terminal.min.css" />
+    <link data-trunk rel="inline" href="index.css">
+    <title>Предложник</title>
+
+    <!-- Yandex.RTB -->
+    <script>window.yaContextCb=window.yaContextCb||[]</script>
+    <script src="https://yandex.ru/ads/system/context.js" async></script>
+  </head>
+  <body>
+    <noscript>
+      <h1>Предложник</h1>
+      <p>
+        ... показывает с какими падежами употребляются предлоги в
+        русском языке. Но, к сожалению, только с помощью Javascript.
+      </p>
+    </noscript>
+  </body>
+</html>
diff --git a/corp/russian/predlozhnik/src/main.rs b/corp/russian/predlozhnik/src/main.rs
new file mode 100644
index 0000000000..56ff04808f
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+++ b/corp/russian/predlozhnik/src/main.rs
@@ -0,0 +1,345 @@
+use yew::html::Scope;
+use yew::prelude::*;
+
+use lazy_static::lazy_static;
+use maplit::hashmap;
+use std::collections::BTreeSet;
+use std::collections::HashMap;
+
+#[derive(Clone, Copy, Debug, Hash, PartialEq, Eq, PartialOrd, Ord)]
+enum Падеж {
+    Именительный,
+    Родительный,
+    Дательный,
+    Винительный,
+    Творительный,
+    Предложный,
+}
+
+impl Падеж {
+    const ВСЕ: [Self; 6] = [
+        Self::Именительный,
+        Self::Родительный,
+        Self::Дательный,
+        Self::Винительный,
+        Self::Творительный,
+        Self::Предложный,
+    ];
+
+    fn вопрос(&self) -> &str {
+        use Падеж::*;
+        match self {
+            Именительный => "кто? Что?",
+            Родительный => "кого? Чего?",
+            Дательный => "кому? Чему?",
+            Винительный => "кого? Что?",
+            Творительный => "кем? Чем?",
+            Предложный => "ком? Чём?",
+        }
+    }
+}
+
+lazy_static! {
+    static ref ПО_ПРЕДЛОГУ: HashMap<&'static str, BTreeSet<Падеж>> = {
+        use Падеж::*;
+
+        hashmap! {
+            "без" => BTreeSet::from([Родительный]),
+            "близ" => BTreeSet::from([Родительный]),
+            "в" => BTreeSet::from([Винительный, Предложный]),
+            "вместо" => BTreeSet::from([Родительный]),
+            "вне" => BTreeSet::from([Родительный]),
+            "внутри" => BTreeSet::from([Родительный]),
+            "возле" => BTreeSet::from([Родительный]),
+            "вокруг" => BTreeSet::from([Родительный]),
+            "вроде" => BTreeSet::from([Родительный]),
+            "для" => BTreeSet::from([Родительный]),
+            "до" => BTreeSet::from([Родительный]),
+            "за" => BTreeSet::from([Винительный, Творительный]),
+            "из" => BTreeSet::from([Родительный]),
+            "из-за" => BTreeSet::from([Родительный]),
+            "из-под" => BTreeSet::from([Родительный]),
+            "к" => BTreeSet::from([Дательный]),
+            "кроме" => BTreeSet::from([Родительный]),
+            "между" => BTreeSet::from([Творительный, Родительный]),
+            "на" => BTreeSet::from([Винительный, Предложный]),
+            "над" => BTreeSet::from([Творительный]),
+            "нет" => BTreeSet::from([Родительный]),
+            "о" => BTreeSet::from([Винительный, Предложный]),
+            "около" => BTreeSet::from([Родительный]),
+            "от" => BTreeSet::from([Родительный]),
+            "перед" => BTreeSet::from([Творительный]),
+            "по" => BTreeSet::from([Винительный, Дательный, Предложный]),
+            "под" => BTreeSet::from([Винительный, Творительный]),
+            "после" => BTreeSet::from([Родительный]),
+            "при" => BTreeSet::from([Предложный]),
+            "про" => BTreeSet::from([Винительный]),
+            "ради" => BTreeSet::from([Родительный]),
+            "с" => BTreeSet::from([Родительный, Винительный, Творительный]),
+            "сквозь" => BTreeSet::from([Винительный]),
+            "среди" => BTreeSet::from([Родительный]),
+            "у" => BTreeSet::from([Родительный]),
+            "через" => BTreeSet::from([Винительный]),
+        }
+    };
+    static ref ПО_ПАДЕЖУ: HashMap<Падеж, BTreeSet<&'static str>> = {
+        let mut m = hashmap!();
+
+        for c in Падеж::ВСЕ {
+            let mut предлоги: BTreeSet<&'static str> = BTreeSet::new();
+            for (k, v) in &*ПО_ПРЕДЛОГУ {
+                if v.contains(&c) {
+                    предлоги.insert(k);
+                }
+            }
+
+            m.insert(c, предлоги);
+        }
+
+        m
+    };
+    static ref ПАДЕЖИ: BTreeSet<Падеж> = BTreeSet::from(Падеж::ВСЕ);
+    static ref ПРЕДЛОГИ: BTreeSet<&'static str> = {
+        let mut s: BTreeSet<&'static str> = BTreeSet::new();
+
+        for п in ПО_ПРЕДЛОГУ.keys() {
+            s.insert(п);
+        }
+
+        s
+    };
+}
+
+fn исключение(предлог: &str, падеж: Падеж) -> Option<Html> {
+    use Падеж::*;
+
+    match (предлог, падеж) {
+        ("в", Винительный) => Some(html! {"Во что? В кого?"}),
+
+        ("о", Винительный) => Some(html! {
+            <>
+              <p>{"О кого? Обо что?"}</p>
+              <p>{"Редко используется. Например:"}</p>
+              <ul>
+                <li>{"Удариться о притолоку."}</li>
+                <li>{"точить о камень."}</li>
+              </ul>
+            </>
+        }),
+
+        ("между", Родительный) => Some(html! {
+            <>
+              <p>{"Между чего?"}</p>
+              <p>{"Редко используется. Только в идиомах и старой литературе:"}</p>
+              <ul>
+                <li>{"Читаю между строк."}</li>
+              </ul>
+            </>
+        }),
+
+        _ => None,
+    }
+}
+
+enum Сообщение {
+    ВыбралПадеж(Option<Падеж>),
+    ВыбралПредлог(Option<&'static str>),
+}
+
+#[derive(Default)]
+struct Модель {
+    падеж: Option<Падеж>,
+    предлог: Option<&'static str>,
+}
+
+struct Вывод {
+    доступные_падежи: BTreeSet<Падеж>,
+    доступные_предлоги: BTreeSet<&'static str>,
+    объяснение: Option<Html>,
+}
+
+fn объясни(падеж: Падеж, предлог: &str) -> Html {
+    let иск = match исключение(предлог, падеж) {
+        Some(exp) => html! { exp },
+        None => html! { format!("{} {}", предлог, падеж.вопрос()) },
+    };
+
+    html! {
+        <div id="obyasnenie">
+          <hr/>
+          <h2>{"Пример:"}</h2>
+          {иск}
+        </div>
+    }
+}
+
+fn ограничить(м: &Модель) -> Вывод {
+    match (м.падеж, &м.предлог) {
+        (Some(пж), Some(пл)) => Вывод {
+            доступные_падежи: (*ПО_ПРЕДЛОГУ)[пл].clone(),
+            доступные_предлоги: (*ПО_ПАДЕЖУ)[&пж].clone(),
+            объяснение: Some(объясни(пж, пл)),
+        },
+
+        (Some(пж), None) => Вывод {
+            доступные_падежи: BTreeSet::from([пж]),
+            доступные_предлоги: (*ПО_ПАДЕЖУ)[&пж].clone(),
+            объяснение: None,
+        },
+
+        (None, Some(пл)) => Вывод {
+            доступные_падежи: (*ПО_ПРЕДЛОГУ)[пл].clone(),
+            доступные_предлоги: BTreeSet::from([*пл]),
+            объяснение: None,
+        },
+
+        (None, None) => Вывод {
+            доступные_падежи: ПАДЕЖИ.clone(),
+            доступные_предлоги: ПРЕДЛОГИ.clone(),
+            объяснение: None,
+        },
+    }
+}
+
+fn класс_кнопки(выбран: bool, доступен: bool) -> String {
+    let класс = "btn ".to_string();
+    класс
+        + match (выбран, доступен) {
+            (true, _) => "btn-primary",
+            (false, true) => "btn-ghost btn-primary",
+            (false, false) => "btn-ghost btn-default",
+        }
+}
+
+fn покажи_предлог(
+    link: &Scope<Модель>,
+    м: &Модель,
+    вв: &Вывод,
+    п: &'static str,
+) -> Html {
+    let выбран = м.предлог == Some(п);
+    let доступен = вв.доступные_предлоги.contains(п);
+    let класс = класс_кнопки(выбран, доступен);
+
+    html! {
+        <button class={класс}
+         onclick={link.callback(move |_| if выбран {
+             Сообщение::ВыбралПредлог(None)
+         } else {
+             Сообщение::ВыбралПредлог(Some(п))
+         })}
+         disabled={!доступен}>
+        {п}
+        </button>
+    }
+}
+
+fn покажи_падеж(
+    link: &Scope<Модель>, м: &Модель, вв: &Вывод, п: Падеж
+) -> Html {
+    let выбран = м.падеж == Some(п);
+    let доступен = вв.доступные_падежи.contains(&п);
+    let класс = класс_кнопки(выбран, доступен);
+
+    html! {
+        <button class={класс}
+         onclick={link.callback(move |_| if выбран {
+             Сообщение::ВыбралПадеж(None)
+         } else {
+             Сообщение::ВыбралПадеж(Some(п))
+         })}
+         disabled={!доступен}>
+        {format!("{:?}", п)}
+        </button>
+    }
+}
+
+impl Component for Модель {
+    type Message = Сообщение;
+    type Properties = ();
+
+    fn create(_ctx: &Context<Self>) -> Self {
+        Default::default()
+    }
+
+    fn update(&mut self, _ctx: &Context<Self>, msg: Self::Message) -> bool {
+        match msg {
+            Сообщение::ВыбралПадеж(пж) => self.падеж = пж,
+            Сообщение::ВыбралПредлог(пл) => self.предлог = пл,
+        }
+
+        true
+    }
+
+    fn view(&self, ctx: &Context<Self>) -> Html {
+        let вв = ограничить(self);
+        let link = ctx.link();
+
+        let кнопки_предлогов = ПРЕДЛОГИ
+            .iter()
+            .map(|п| покажи_предлог(link, self, &вв, п))
+            .collect::<Html>();
+
+        let кнопки_падежов = ПАДЕЖИ
+            .iter()
+            .map(|п| покажи_падеж(link, self, &вв, *п))
+            .collect::<Html>();
+
+        let объяснение = вв.объяснение.map(|exp| exp).unwrap_or_else(|| html! {});
+
+        let footer = html! {
+            <footer>
+              <hr/>
+              <p class="footer">
+                <a href="https://code.tvl.fyi/tree/corp/russian/predlozhnik">{"код"}</a>
+                {" | "}
+                {"сделано "}<a href="https://tvl.su">{"ООО \"ТВЛ\""}</a>
+              </p>
+            </footer>
+        };
+
+        let код_рекламы = r#"
+window.yaContextCb.push(()=>{
+  Ya.Context.AdvManager.render({
+    renderTo: 'yandex_rtb_R-A-1773485-1',
+    blockId: 'R-A-1773485-1'
+  })
+})
+"#;
+
+        let реклама = html! {
+            <div id="ad">
+              <div id="yandex_rtb_R-A-1773485-1"></div>
+              <script>{код_рекламы}</script>
+            </div>
+        };
+
+        html! {
+            <>
+                <div id="header">
+                  <h1>{"Предложник"}</h1>
+                  <p>{"... показывает с какими падежами употребляются предлоги в русском языке."}</p>
+                </div>
+
+                <h2>{"Выбирай предлог:"}</h2>
+                <div id="predlogi">
+                  {кнопки_предлогов}
+                </div>
+                <hr/>
+
+                <h2>{"Выбирай падеж:"}</h2>
+                <div id="padezhi">
+                  {кнопки_падежов}
+                </div>
+
+                {объяснение}
+                {footer}
+                {реклама}
+            </>
+        }
+    }
+}
+
+fn main() {
+    yew::start_app::<Модель>();
+}