From fa0a2969b8d651bc335bc87a32ae57c6a3c7939d Mon Sep 17 00:00:00 2001
From: Yanick Champoux <yanick@babyl.dyndns.org>
Date: Thu, 17 Oct 2019 11:15:10 -0400
Subject: [PATCH] so it begins

---
 README.md       | 127 ++++++++++++++++++++++++++++++++++
 babel.config.js |  12 ++++
 package.json    |  15 ++++
 src/index.js    | 138 +++++++++++++++++++++++++++++++++++++
 src/test.js     | 178 ++++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 470 insertions(+)
 create mode 100644 README.md
 create mode 100644 babel.config.js
 create mode 100644 package.json
 create mode 100644 src/index.js
 create mode 100644 src/test.js

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..c855e28
--- /dev/null
+++ b/README.md
@@ -0,0 +1,127 @@
+
+# What's Updux?
+
+So, I'm a fan of [Redux][]. Two days ago I discovered
+[rematch][] alonside a few other frameworks built atop Redux. 
+
+It has a couple of pretty good ideas that removes some of the 
+boilerplate. Keeping mutations and asynchronous effects close to the 
+reducer definition, à la [VueX][]? Nice. Automatically infering the 
+actions from the said mutations and effects? Genius!
+
+But it also enforces a flat hierarchy of reducers -- where
+is the fun in that? And I'm also having a strong love for
+[Updeep][], so I want reducer state updates to leverage the heck out of it.
+
+All that to say, I had some fun yesterday and hacked a proto-lovechild
+of `Rematch` and `Updeep`, with a dash of [VueX][] inspiration. 
+I call it... `Updux`.
+
+## Example
+
+#### battle.js
+
+```
+import { updux } from 'updux';
+
+import game from './game';
+import log from './log';
+import bogeys from './bogeys';
+
+const { createStore } = updux({
+    reducers: { game, log, bogeys }
+})
+
+export default createStore;
+```
+
+#### game.js
+
+
+```
+import { updux } from 'updux';
+import _ from 'lodash';
+import u from 'updeep';
+
+import { calculateMovement } from 'game/rules';
+
+
+export default updux({
+    initial: { game: "", players: [], turn: 0, },
+    mutations: {
+        init_game: ({game: { name, players }}) => {name, players},
+        play_turn: () => u({ turn: x => x+1 }),
+    },
+    effects: {
+        play_turn: ({getState,dispatch}) => next => action => {
+
+            const bogeys = api.getState().bogeys;
+
+            // only allow the turn to be played if
+            // all ships have their orders in
+            if( bogeys.any( bogey => ! bogey.orders ) ) return;
+
+            bogeys.forEach( bogey => {
+                dispatch.move( calculateMovement(bogey) )
+            } );
+
+            next(action); 
+        },
+    }
+});
+```
+
+
+#### log.js
+
+
+```
+import { updux } from 'updux';
+
+export default updux({
+    initial: [],
+    actions: {
+        '*': (payload,action) => state => [ ...state, action ],
+    },
+});
+```
+
+#### bogeys.js
+
+```
+import { updux } from 'updux';
+import _ from 'lodash';
+
+export default updux({
+    initial: [],
+    mutations: {
+        init_game: ({bogeys}) => () => _.keyBy( bogeys, 'id' ),
+        move: ({position}) => u({ position }),
+    },
+});
+```
+
+
+#### myGame.js
+
+```
+import Battle from './battle';
+
+const battle = Battle();
+
+battle.dispatch.init_game({
+    name: 'Gemini Prime',
+    players: [ 'yenzie' ],
+    bogeys: [ { id: 'Enkidu' } ]
+});
+
+battle.dispatch.play_game();
+
+....
+```
+
+
+[Redux]: https://redux.js.org
+[rematch]: https://rematch.github.io
+[Updeep]: https://github.com/substantial/updeep
+[VueX]: https://vuex.vuejs.org/
diff --git a/babel.config.js b/babel.config.js
new file mode 100644
index 0000000..f037a1a
--- /dev/null
+++ b/babel.config.js
@@ -0,0 +1,12 @@
+module.exports = {
+  presets: [
+    [
+      '@babel/preset-env',
+      {
+        targets: {
+          node: 'current',
+        },
+      },
+    ],
+  ],
+};
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..de6431b
--- /dev/null
+++ b/package.json
@@ -0,0 +1,15 @@
+{
+  "name": "updux",
+  "version": "0.0.1",
+  "main": "index.js",
+  "license": "MIT",
+  "dependencies": {
+    "@babel/core": "^7.6.4",
+    "@babel/preset-env": "^7.6.3",
+    "babel-jest": "^24.9.0",
+    "jest": "^24.9.0",
+    "lodash": "^4.17.15",
+    "redux": "^4.0.4",
+    "updeep": "^1.2.0"
+  }
+}
diff --git a/src/index.js b/src/index.js
new file mode 100644
index 0000000..c02266f
--- /dev/null
+++ b/src/index.js
@@ -0,0 +1,138 @@
+import fp from 'lodash/fp';
+import u from 'updeep';
+
+import { createStore, applyMiddleware } from 'redux';
+
+function actionFor(type) {
+  return (payload = null, meta = null) => {
+    return fp.pickBy(v => v !== null)({type, payload, meta});
+  };
+}
+
+function buildInitial({initial = {}, reducers = {}}) {
+  let state = initial;
+
+  if (fp.isPlainObject(initial)) {
+    initial = fp.mergeAll([
+      fp.mapValues(fp.getOr({}, 'initial'), reducers),
+      initial,
+    ]);
+  }
+
+  return initial;
+}
+
+function buildActions({mutations = {}, reducers = {}}) {
+  let actions = fp.mergeAll(fp.map(fp.getOr({}, 'actions'), reducers)) || {};
+
+  Object.keys(mutations).forEach(type => {
+    if (!actions[type]) {
+      actions[type] = actionFor(type);
+    }
+  });
+
+  return actions;
+}
+
+function buildMutations({mutations = {}, reducers = {}}) {
+  let subMut = {};
+
+  for (let slice in reducers) {
+    for (let mutation in reducers[slice].mutations) {
+      subMut = u(
+        {
+          [mutation]: {
+            [slice]: u.constant(reducers[slice].mutations[mutation]),
+          },
+        },
+        subMut,
+      );
+    }
+  }
+
+  subMut = fp.mapValues(updates => action =>
+    u(fp.mapValues(f => f(action))(updates)),
+  )(subMut);
+
+  for (let name in mutations) {
+    if (subMut[name]) {
+      const pre = subMut[name];
+
+      subMut[name] = action => state =>
+        mutations[name](action)(pre(action)(state));
+    } else {
+      subMut[name] = mutations[name];
+    }
+  }
+
+  return subMut;
+}
+
+function buildMiddleware({effects={},reducers={}},{actions}) {
+    return api => {
+
+        for ( let type in actions ) {
+            api.dispatch[type] = (...args) => api.dispatch( actions[type](...args) );
+        }
+
+        return original_next => {
+    return [
+        ...fp.toPairs(effects).map(([type,effect])=> {
+        return api => next => action => {
+            console.log(action);
+
+            if( action.type !== type ) return next(action);
+
+            return effect(api)(next)(action);
+        };
+    }),
+        ...fp.map( 'middleware', reducers )
+    ].filter(x=>x).reduceRight( (next,mw) => mw(api)(next), original_next )
+    }}
+}
+
+function updux(config) {
+  const dux = {};
+
+  dux.actions = buildActions(config);
+
+  dux.initial = buildInitial(config);
+
+  dux.mutations = buildMutations(config);
+
+  dux.upreducer = action => state => {
+    if (state === null) state = dux.initial;
+
+    const a =
+      dux.mutations[action.type] ||
+      dux.mutations['*'] ||
+      (() => state => state);
+
+    return a(action.payload, action)(state);
+  };
+
+  dux.reducer = (state, action) => {
+    return dux.upreducer(action)(state);
+  };
+
+  dux.middleware = buildMiddleware(config,dux);
+
+  dux.createStore = () => {
+      const store =  createStore( dux.reducer, dux.initial,
+          applyMiddleware( dux.middleware)
+        );
+      for ( let a in dux.actions ) {
+          store.dispatch[a] = (...args) => {
+              store.dispatch(dux.actions[a](...args))
+          };
+      }
+
+      return store;
+  }
+
+
+
+  return dux;
+}
+
+export default updux;
diff --git a/src/test.js b/src/test.js
new file mode 100644
index 0000000..a0c3552
--- /dev/null
+++ b/src/test.js
@@ -0,0 +1,178 @@
+import updux from '.';
+
+test('actions from mutations', () => {
+  const {
+    actions: {foo, bar},
+  } = updux({
+    mutations: {
+      foo: () => x => x,
+    },
+  });
+
+  expect(foo()).toEqual({type: 'foo'});
+
+  expect(foo(true)).toEqual({type: 'foo', payload: true});
+
+  expect(foo({bar: 2}, {timestamp: 613})).toEqual({
+    type: 'foo',
+    payload: {bar: 2},
+    meta: {timestamp: 613},
+  });
+});
+
+test('reducer', () => {
+  const {actions, reducer} = updux({
+    initial: {counter: 1},
+    mutations: {
+      inc: () => ({counter}) => ({counter: counter + 1}),
+    },
+  });
+
+  let state = reducer(null, {});
+
+  expect(state).toEqual({counter: 1});
+
+  state = reducer(state, actions.inc());
+
+  expect(state).toEqual({counter: 2});
+});
+
+test( 'sub reducers', () => {
+    const foo = updux({
+        initial: 1,
+        mutations: {
+            doFoo: () => (x) => x + 1,
+            doAll: () => x => x + 10,
+        },
+    });
+
+    const bar = updux({
+        initial: 'a',
+        mutations: {
+            doBar: () => x => x + 'a',
+            doAll: () => x => x + 'b',
+        }
+    });
+
+    const { initial, actions, reducer } = updux({
+        reducers: {
+            foo, bar
+        }
+    });
+
+    expect(initial).toEqual({ foo: 1, bar: 'a' });
+
+    expect(Object.keys(actions)).toHaveLength(3);
+
+    let state = reducer(null,{});
+
+    expect(state).toEqual({ foo: 1, bar: 'a' });
+
+    state = reducer(state, actions.doFoo() );
+
+    expect(state).toEqual({ foo: 2, bar: 'a' });
+
+    state = reducer(state, actions.doBar() );
+
+    expect(state).toEqual({ foo: 2, bar: 'aa' });
+
+    state = reducer(state, actions.doAll() );
+
+    expect(state).toEqual({ foo: 12, bar: 'aab' });
+
+});
+
+test('precedence between root and sub-reducers', () => {
+    const {
+        initial,
+        reducer,
+        actions,
+    } = updux({
+        initial: {
+            foo: { bar: 4 },
+        },
+        mutations: {
+            inc: () => state => {
+                return {
+                    ...state,
+                    surprise: state.foo.bar
+                }
+            }
+        },
+        reducers: {
+            foo: updux({
+                initial: {
+                    bar: 2,
+                    quux: 3,
+                },
+                mutations: {
+                    inc: () => state => ({...state, bar: state.bar + 1 })
+                },
+            }),
+        }
+    });
+
+    expect(initial).toEqual({
+        foo: { bar: 4, quux: 3 }
+    });
+
+    expect( reducer(null,actions.inc() ) ).toEqual({
+        foo: { bar: 5, quux: 3 }, surprise: 5
+    });
+
+});
+
+function timeout(ms) {
+    return new Promise(resolve => setTimeout(resolve, ms));
+}
+
+test( 'middleware', async () => {
+    const {
+        middleware,
+        createStore
+    } = updux({
+        initial: "",
+        mutations: {
+            inc: (addition) => state => state + addition,
+            doEeet: () => state => {
+                console.log("up", state);
+
+                return state + 'Z';
+            },
+        },
+        effects: {
+            doEeet: api => next => async action => {
+                console.log(api);
+                api.dispatch.inc('a');
+                next(action);
+                await timeout(1000);
+                api.dispatch.inc('c');
+            }
+        },
+        reducers: {
+            foo: updux({
+                effects: {
+                    doEeet: (api) => next => action => {
+                        console.log("in foo",api);
+
+                        api.dispatch({ type: 'inc', payload: 'b'});
+                        next(action);
+                    }
+                }
+            }),
+        }
+    });
+
+    const store = createStore();
+
+    console.log(store);
+
+    store.dispatch.doEeet();
+
+    expect(store.getState()).toEqual( 'abZ' );
+
+    await timeout(1000);
+
+    expect(store.getState()).toEqual( 'abZc' );
+
+});