@harlem/core/dist/index.bundler.mjs

Powerfully simple global state management for Vue 3

// src/event-emitter.ts
function createEventBus() {
  const listeners = /* @__PURE__ */ new Map();
  function on2(event, handler) {
    const handlers = listeners.get(event) || /* @__PURE__ */ new Set();
    handlers.add(handler);
    listeners.set(event, handlers);
    return {
      dispose: () => off2(event, handler)
    };
  }
  function off2(event, handler) {
    const handlers = listeners.get(event);
    if (!handlers) {
      return;
    }
    handlers.delete(handler);
    if (!handlers.size) {
      listeners.delete(event);
    }
  }
  function once2(event, handler) {
    const callback = (payload) => {
      handler(payload);
      off2(event, callback);
    };
    return on2(event, callback);
  }
  function emit(event, payload) {
    const handlers = listeners.get(event);
    if (handlers) {
      handlers.forEach((handler) => handler(payload));
    }
  }
  return {
    on: on2,
    off: off2,
    once: once2,
    emit
  };
}

// src/constants.ts
import {
  objectClone
} from "@harlem/utilities";
var SENDER = "core";
var EVENTS = {
  core: {
    installed: "core:installed"
  },
  store: {
    created: "store:created",
    ready: "store:ready",
    destroyed: "store:destroyed"
  },
  mutation: {
    before: "mutation:before",
    after: "mutation:after",
    success: "mutation:success",
    error: "mutation:error"
  },
  action: {
    before: "action:before",
    after: "action:after",
    success: "action:success",
    error: "action:error"
  },
  ssr: {
    initServer: "ssr:init:server",
    initClient: "ssr:init:client"
  },
  devtools: {
    update: "devtools:update",
    reset: "devtools:reset"
  }
};
var MUTATIONS = {
  snapshot: "core:snapshot",
  reset: "core:reset"
};
var PRODUCERS = {
  read: (value) => value,
  write: (value) => value,
  payload: (value) => objectClone(value)
};
var INTERNAL = {
  prefix: "$harlem:",
  pattern: /^\$harlem:/
};

// src/store.ts
import {
  computed,
  effectScope,
  reactive,
  readonly
} from "vue";
import {
  functionIdentity,
  objectClone as objectClone2,
  objectFromPath,
  objectSet,
  objectTrace
} from "@harlem/utilities";
function localiseHandler(name, handler) {
  return (payload) => {
    if (payload && payload.store === name) {
      handler(payload);
    }
  };
}
function createInternalStore(name, initialState, eventBus, options) {
  var _a;
  const {
    allowsOverwrite,
    producers
  } = {
    allowsOverwrite: true,
    ...options,
    producers: {
      ...PRODUCERS,
      ...options == null ? void 0 : options.producers
    }
  };
  const registrations = {};
  const flags = /* @__PURE__ */ new Map();
  const scope = effectScope();
  const stack = /* @__PURE__ */ new Set();
  let isSuppressing = false;
  const writeState = reactive(initialState);
  const readState = readonly(writeState);
  let resetSnapshot;
  function emit(event, sender, data) {
    if (!scope.active || isSuppressing) {
      return;
    }
    const payload = {
      data,
      sender,
      store: name
    };
    eventBus.emit(event, payload);
  }
  function on2(event, handler) {
    return eventBus.on(event, localiseHandler(name, handler));
  }
  function once2(event, handler) {
    return eventBus.once(event, localiseHandler(name, handler));
  }
  function track(callback) {
    return scope.run(callback);
  }
  function hasRegistration(group, name2) {
    var _a2;
    return !!((_a2 = registrations[group]) == null ? void 0 : _a2.has(name2));
  }
  function getRegistration(group, name2) {
    var _a2;
    return (_a2 = registrations[group]) == null ? void 0 : _a2.get(name2);
  }
  function register(group, name2, producer, type = "other") {
    if (!name2) {
      throw new Error("Registration name cannot be empty");
    }
    if (!(group in registrations)) {
      registrations[group] = /* @__PURE__ */ new Map();
    }
    if (!allowsOverwrite && hasRegistration(group, name2)) {
      throw new Error(`A ${group} named ${name2} has already been registered on this store`);
    }
    registrations[group].set(name2, {
      type,
      producer
    });
  }
  function unregister(group, name2) {
    var _a2;
    (_a2 = registrations[group]) == null ? void 0 : _a2.delete(name2);
  }
  function suppress(callback) {
    isSuppressing = true;
    try {
      return callback();
    } finally {
      isSuppressing = false;
    }
  }
  function getter(name2, getter2) {
    const output = track(() => computed(() => getter2(readState)));
    register("getters", name2, () => output.value, "computed");
    return output;
  }
  function mutate(name2, sender, mutator, payload) {
    var _a2, _b;
    if (!scope.active) {
      throw new Error("The current store has been destroyed. Mutations can no longer take place.");
    }
    if (stack.has(name2)) {
      throw new Error("Circular mutation reference detected. Avoid calling mutations inside other mutations to prevent circular references.");
    }
    stack.add(name2);
    let result;
    const trigger = (event) => emit(event, sender, {
      name: name2,
      payload,
      result
    });
    trigger(EVENTS.mutation.before);
    try {
      const producedState = (_a2 = producers.write(writeState)) != null ? _a2 : writeState;
      const producedPayload = (_b = producers.payload(payload)) != null ? _b : payload;
      result = mutator(producedState, producedPayload);
      trigger(EVENTS.mutation.success);
    } catch (error) {
      trigger(EVENTS.mutation.error);
      throw error;
    } finally {
      stack.delete(name2);
      trigger(EVENTS.mutation.after);
    }
    return result;
  }
  function mutation(name2, mutator) {
    const mutation2 = (payload) => {
      return mutate(name2, SENDER, mutator, payload);
    };
    register("mutations", name2, () => mutation2);
    return mutation2;
  }
  function action(name2, body) {
    const mutate2 = (mutator) => write(name2, SENDER, mutator);
    const action2 = async (payload) => {
      var _a2;
      let result;
      const trigger = (event) => emit(event, SENDER, {
        name: name2,
        payload,
        result
      });
      trigger(EVENTS.action.before);
      try {
        const producedPayload = (_a2 = producers.payload(payload)) != null ? _a2 : payload;
        result = await body(producedPayload, mutate2);
        trigger(EVENTS.action.success);
      } catch (error) {
        trigger(EVENTS.action.error);
        throw error;
      } finally {
        trigger(EVENTS.action.after);
      }
      return result;
    };
    register("actions", name2, () => action2);
    return action2;
  }
  function snapshot() {
    const snapshot2 = objectClone2(initialState);
    const {
      value,
      getNodes,
      resetNodes
    } = objectTrace();
    const apply = (branchAccessor = functionIdentity, mutationName = MUTATIONS.snapshot) => {
      write(mutationName, SENDER, (state2) => {
        if (!snapshot2) {
          return console.warn("Couldn't find snapshot for this operation!");
        }
        resetNodes();
        branchAccessor(value);
        const nodes = getNodes();
        const source = objectFromPath(snapshot2, nodes);
        objectSet(state2, nodes, objectClone2(source));
      });
    };
    return {
      apply,
      get state() {
        return objectClone2(snapshot2);
      }
    };
  }
  function reset(branchAccessor = functionIdentity) {
    resetSnapshot == null ? void 0 : resetSnapshot.apply(branchAccessor, MUTATIONS.reset);
  }
  function write(name2, sender, mutator, suppressEvent) {
    const mutation2 = () => mutate(name2, sender, mutator, void 0);
    return suppressEvent ? suppress(mutation2) : mutation2();
  }
  function destroy() {
    scope.stop();
  }
  once2(EVENTS.store.ready, () => resetSnapshot = snapshot());
  on2(EVENTS.devtools.reset, () => reset());
  const state = (_a = producers.read(readState)) != null ? _a : readState;
  return {
    name,
    allowsOverwrite,
    flags,
    producers,
    registrations,
    on: on2,
    once: once2,
    emit,
    state,
    getter,
    mutation,
    action,
    write,
    snapshot,
    reset,
    register,
    unregister,
    hasRegistration,
    getRegistration,
    track,
    suppress,
    destroy
  };
}

// src/index.ts
import {
  matchGetFilter,
  objectLock,
  typeIsFunction,
  typeIsMatchable
} from "@harlem/utilities";
function createInstance() {
  const eventBus = createEventBus();
  const stores = /* @__PURE__ */ new Map();
  let installed = false;
  function validateStoreCreation(name) {
    const store = stores.get(name);
    if (store && !store.allowsOverwrite) {
      throw new Error(`A store named ${name} has already been registered.`);
    }
  }
  function emitCreated(store, state) {
    const created = () => {
      store.emit(EVENTS.ssr.initClient, SENDER, state);
      store.emit(EVENTS.store.created, SENDER, state);
      store.emit(EVENTS.ssr.initServer, SENDER, state);
      store.emit(EVENTS.store.ready, SENDER, state);
      store.emit(EVENTS.devtools.update, SENDER, state);
    };
    if (installed) {
      return created();
    }
    eventBus.once(EVENTS.core.installed, created);
  }
  function getExtensionApis(store, extensions) {
    return extensions.reduce((output, extension) => {
      let result = {};
      try {
        result = extension(store) || {};
      } catch (e) {
        result = {};
      }
      return {
        ...output,
        ...result
      };
    }, {});
  }
  function installPlugin(plugin, app) {
    if (!typeIsFunction(plugin)) {
      return;
    }
    const lockedStores = objectLock(stores, [
      "set",
      "delete",
      "clear"
    ]);
    try {
      plugin(app, eventBus, lockedStores);
    } catch (error) {
      console.warn("Failed to install Harlem plugin. Skipping.");
    }
  }
  function createStore2(name, state, options) {
    const {
      allowsOverwrite,
      producers: providers,
      extensions
    } = {
      allowsOverwrite: true,
      extensions: [],
      ...options
    };
    validateStoreCreation(name);
    const store = createInternalStore(name, state, eventBus, {
      allowsOverwrite,
      producers: providers
    });
    const destroy = () => {
      stores.delete(name);
      store.destroy();
      store.emit(EVENTS.store.destroyed, SENDER, state);
      store.emit(EVENTS.devtools.update, SENDER, state);
    };
    const getTrigger = (eventName) => {
      return (matcher, handler) => {
        const filter = matchGetFilter(
          typeIsMatchable(matcher) ? matcher : {
            include: matcher
          }
        );
        return store.on(eventName, (event) => {
          if (event && filter(event.data.name)) {
            handler(event.data);
          }
        });
      };
    };
    const onBeforeMutation = getTrigger(EVENTS.mutation.before);
    const onAfterMutation = getTrigger(EVENTS.mutation.after);
    const onMutationSuccess = getTrigger(EVENTS.mutation.success);
    const onMutationError = getTrigger(EVENTS.mutation.error);
    const onBeforeAction = getTrigger(EVENTS.action.before);
    const onAfterAction = getTrigger(EVENTS.action.after);
    const onActionSuccess = getTrigger(EVENTS.action.success);
    const onActionError = getTrigger(EVENTS.action.error);
    const extensionApis = getExtensionApis(store, extensions);
    stores.set(name, store);
    emitCreated(store, state);
    return {
      destroy,
      onBeforeMutation,
      onAfterMutation,
      onMutationSuccess,
      onMutationError,
      onBeforeAction,
      onAfterAction,
      onActionSuccess,
      onActionError,
      state: store.state,
      getter: store.getter.bind(store),
      mutation: store.mutation.bind(store),
      action: store.action.bind(store),
      snapshot: store.snapshot.bind(store),
      reset: store.reset.bind(store),
      suppress: store.suppress.bind(store),
      on: store.on.bind(store),
      once: store.once.bind(store),
      ...extensionApis
    };
  }
  function createVuePlugin2(options) {
    return {
      install(app) {
        const {
          plugins
        } = {
          plugins: [],
          ...options
        };
        if (plugins) {
          plugins.forEach((plugin) => installPlugin(plugin, app));
        }
        installed = true;
        eventBus.emit(EVENTS.core.installed);
      }
    };
  }
  return {
    createVuePlugin: createVuePlugin2,
    createStore: createStore2,
    on: eventBus.on,
    once: eventBus.once,
    off: eventBus.off
  };
}
var {
  on,
  off,
  once,
  createVuePlugin,
  createStore
} = createInstance();
if (typeof window !== "undefined") {
  window.$harlem = {
    createInstance
  };
}
export {
  EVENTS,
  INTERNAL,
  PRODUCERS,
  createInstance,
  createStore,
  createVuePlugin,
  off,
  on,
  once
};