From 3a1e561a27ccead181230aa6ce22d70504b135a4 Mon Sep 17 00:00:00 2001
From: Eric Y Liu <ericyl.us@gmail.com>
Date: Fri, 19 Mar 2021 13:25:45 -0700
Subject: [PATCH] feat(context-menu): add initial ContextMenu

---
 docs/src/pages/_layout.svelte                |  14 +-
 src/ContextMenu/ContextMenu.svelte           |  99 ++++++++++
 src/ContextMenu/ContextMenuDivider.svelte    |   1 +
 src/ContextMenu/ContextMenuGroup.svelte      |  35 ++++
 src/ContextMenu/ContextMenuOption.svelte     | 182 +++++++++++++++++++
 src/ContextMenu/ContextMenuRadioGroup.svelte |  24 +++
 src/ContextMenu/index.js                     |   5 +
 src/index.js                                 |   7 +
 8 files changed, 364 insertions(+), 3 deletions(-)
 create mode 100644 src/ContextMenu/ContextMenu.svelte
 create mode 100644 src/ContextMenu/ContextMenuDivider.svelte
 create mode 100644 src/ContextMenu/ContextMenuGroup.svelte
 create mode 100644 src/ContextMenu/ContextMenuOption.svelte
 create mode 100644 src/ContextMenu/ContextMenuRadioGroup.svelte
 create mode 100644 src/ContextMenu/index.js

diff --git a/docs/src/pages/_layout.svelte b/docs/src/pages/_layout.svelte
index 162e382b..bb4359af 100644
--- a/docs/src/pages/_layout.svelte
+++ b/docs/src/pages/_layout.svelte
@@ -20,7 +20,7 @@
   import Footer from "../components/Footer.svelte";
 
   const deprecated = ["ToggleSmall", "Icon"];
-  const new_components = ["Popover"];
+  const new_components = ["Popover", "ContextMenu"];
 
   let isOpen = false;
   let isSideNavOpen = true;
@@ -105,10 +105,18 @@
           >
             {child.title}
             {#if deprecated.includes(child.title)}
-              <Tag size="sm" type="red">Deprecated</Tag>
+              <Tag size="sm" type="red" style="margin-top: 0; margin-bottom: 0">
+                Deprecated
+              </Tag>
             {/if}
             {#if new_components.includes(child.title)}
-              <Tag size="sm" type="green">New</Tag>
+              <Tag
+                size="sm"
+                type="green"
+                style="margin-top: 0; margin-bottom: 0"
+              >
+                New
+              </Tag>
             {/if}
           </SideNavMenuItem>
         {/each}
diff --git a/src/ContextMenu/ContextMenu.svelte b/src/ContextMenu/ContextMenu.svelte
new file mode 100644
index 00000000..81d8b90b
--- /dev/null
+++ b/src/ContextMenu/ContextMenu.svelte
@@ -0,0 +1,99 @@
+<script>
+  /**
+   * Set to `true` to open the menu
+   * Either `x` and `y` must be greater than zero
+   */
+  export let open = false;
+
+  /** Specify the horizontal offset of the menu position */
+  export let x = 0;
+
+  /** Specify the vertical offset of the menu position */
+  export let y = 0;
+
+  /** Obtain a reference to the unordered list HTML element */
+  export let ref = null;
+
+  import {
+    setContext,
+    getContext,
+    afterUpdate,
+    createEventDispatcher,
+  } from "svelte";
+  import { writable } from "svelte/store";
+
+  const dispatch = createEventDispatcher();
+  const position = writable([x, y]);
+  const ctx = getContext("ContextMenu");
+
+  let direction = 1;
+  let prevX = 0;
+  let prevY = 0;
+
+  function close() {
+    open = false;
+    x = 0;
+    y = 0;
+  }
+
+  setContext("ContextMenu", { position, close });
+
+  afterUpdate(() => {
+    if (open && level === 1) {
+      if (prevX !== x || prevY !== y) ref.focus();
+      prevX = x;
+      prevY = y;
+    } else {
+      dispatch("close");
+    }
+  });
+
+  $: level = !ctx ? 1 : 2;
+</script>
+
+<svelte:window
+  on:contextmenu|preventDefault="{(e) => {
+    if (level > 1) return;
+
+    if (open || x === 0) x = e.x;
+    if (open || y === 0) y = e.y;
+
+    position.set([x, y]);
+    open = true;
+  }}"
+  on:click="{(e) => {
+    if (!open) return;
+    if (e.target.contains(ref)) close();
+  }}"
+/>
+
+<ul
+  bind:this="{ref}"
+  role="menu"
+  tabindex="-1"
+  data-direction="{direction}"
+  data-level="{level}"
+  class:bx--context-menu="{true}"
+  class:bx--context-menu--open="{open}"
+  class:bx--context-menu--invisible="{open && x === 0 && y === 0}"
+  class:bx--context-menu--root="{level === 1}"
+  {...$$restProps}
+  style="left: {x}px; top: {y}px; {$$restProps.style}"
+  on:click
+  on:click="{({ target }) => {
+    if (
+      target &&
+      target.closest('[tabindex]') &&
+      target.closest('[tabindex]').getAttribute('role') === 'menuitem'
+    ) {
+      return;
+    }
+    close();
+  }}"
+  on:keydown
+  on:keydown="{(e) => {
+    // TODO: add focus logic
+  }}"
+>
+  <slot />
+</ul>
diff --git a/src/ContextMenu/ContextMenuDivider.svelte b/src/ContextMenu/ContextMenuDivider.svelte
new file mode 100644
index 00000000..98605565
--- /dev/null
+++ b/src/ContextMenu/ContextMenuDivider.svelte
@@ -0,0 +1 @@
+<li role="separator" class:bx--context-menu-divider="{true}"></li>
diff --git a/src/ContextMenu/ContextMenuGroup.svelte b/src/ContextMenu/ContextMenuGroup.svelte
new file mode 100644
index 00000000..68781d1f
--- /dev/null
+++ b/src/ContextMenu/ContextMenuGroup.svelte
@@ -0,0 +1,35 @@
+<script>
+  /** @type {string[]} */
+  export let selectedIds = [];
+
+  export let label = "";
+
+  import { setContext } from "svelte";
+  import { writable } from "svelte/store";
+
+  const currentIds = writable([]);
+
+  setContext("ContextMenuGroup", {
+    currentIds,
+    addOption: ({ id }) => {
+      if (!selectedIds.includes(id)) {
+        selectedIds = [...selectedIds, id];
+      }
+    },
+    toggleOption: ({ id }) => {
+      if (!selectedIds.includes(id)) {
+        selectedIds = [...selectedIds, id];
+      } else {
+        selectedIds = selectedIds.filter((_) => _ !== id);
+      }
+    },
+  });
+
+  $: currentIds.set(selectedIds);
+</script>
+
+<li role="none">
+  <ul role="group" aria-label="{label}">
+    <slot />
+  </ul>
+</li>
diff --git a/src/ContextMenu/ContextMenuOption.svelte b/src/ContextMenu/ContextMenuOption.svelte
new file mode 100644
index 00000000..95cb7f30
--- /dev/null
+++ b/src/ContextMenu/ContextMenuOption.svelte
@@ -0,0 +1,182 @@
+<script>
+  export let disabled = false;
+  export let icon = undefined;
+  export let indented = false;
+  export let label = "";
+  export let selected = false;
+  export let selectable = false;
+  export let shortcut = "";
+  export let id = "ccs-" + Math.random().toString(36);
+  export let ref = null;
+
+  import { onMount, getContext, createEventDispatcher } from "svelte";
+  import ContextMenu from "./ContextMenu.svelte";
+  import Checkmark16 from "carbon-icons-svelte/lib/Checkmark16/Checkmark16.svelte";
+  import CaretRight16 from "carbon-icons-svelte/lib/CaretRight16/CaretRight16.svelte";
+
+  const dispatch = createEventDispatcher();
+  const ctx = getContext("ContextMenu");
+  const ctxGroup = getContext("ContextMenuGroup");
+  const ctxRadioGroup = getContext("ContextMenuRadioGroup");
+
+  let unsubCurrentIds = undefined;
+  let unsubCurrentId = undefined;
+  let initialSelected = false;
+  let timeoutHover = undefined;
+  let rootMenuPosition = [0, 0];
+
+  const unsubPosition = ctx.position.subscribe((position) => {
+    rootMenuPosition = position;
+  });
+
+  onMount(() => {
+    initialSelected = selected;
+
+    if (ctxGroup) {
+      unsubCurrentIds = ctxGroup.currentIds.subscribe((ids) => {
+        selected = ids.includes(id);
+      });
+    }
+
+    if (ctxRadioGroup) {
+      unsubCurrentId = ctxRadioGroup.currentId.subscribe((_id) => {
+        selected = id === _id;
+      });
+    }
+
+    return () => {
+      unsubPosition();
+      if (unsubCurrentIds) unsubCurrentIds();
+      if (unsubCurrentId) unsubCurrentId();
+      if (typeof timeoutHover === "number") clearTimeout(timeoutHover);
+    };
+  });
+
+  $: isSelectable = !!ctxGroup || initialSelected || selectable;
+  $: isRadio = !!ctxRadioGroup;
+
+  $: if (isSelectable) {
+    indented = true;
+
+    if (selected) {
+      if (ctxGroup) ctxGroup.addOption({ id });
+      icon = Checkmark16;
+    } else {
+      icon = undefined;
+    }
+  }
+
+  let submenuOpen = false;
+  let submenuPosition = [0, 0];
+
+  $: subOptions = $$slots.default;
+  $: if (submenuOpen) {
+    const { width, y } = ref.getBoundingClientRect();
+    submenuPosition = [rootMenuPosition[0] + width, y];
+  }
+
+  let role = "menuitem";
+
+  $: {
+    if (isSelectable) role = "menuitemcheckbox";
+    if (isRadio) {
+      role = "menuitemradio";
+
+      if (selected) {
+        if (ctxRadioGroup) ctxRadioGroup.setOption({ id });
+        icon = Checkmark16;
+      } else {
+        icon = undefined;
+      }
+    }
+  }
+</script>
+
+<li
+  bind:this="{ref}"
+  role="{role}"
+  tabindex="-1"
+  aria-disabled="{!subOptions && disabled}"
+  aria-haspopup="{subOptions ? true : undefined}"
+  aria-expanded="{subOptions ? submenuOpen : undefined}"
+  class:bx--context-menu-option="{true}"
+  class:bx--context-menu-option--disabled="{true}"
+  class:bx--context-menu-option--active="{subOptions && submenuOpen}"
+  indented="{isSelectable || isRadio}"
+  aria-checked="{isSelectable || isRadio ? selected : undefined}"
+  {...$$restProps}
+  on:keydown
+  on:keydown="{(e) => {}}"
+  on:mouseenter
+  on:mouseenter="{(e) => {
+    if (subOptions) {
+      timeoutHover = setTimeout(() => {
+        submenuOpen = true;
+      }, 150);
+    }
+  }}"
+  on:mouseleave
+  on:mouseleave="{(e) => {
+    if (subOptions) {
+      if (typeof timeoutHover === 'number') clearTimeout(timeoutHover);
+      submenuOpen = false;
+    }
+  }}"
+  on:click="{() => {
+    if (disabled) return ctx.close();
+    if (subOptions) return;
+
+    if (!!ctxGroup) {
+      ctxGroup.toggleOption({ id });
+    } else if (!!ctxRadioGroup) {
+      ctxRadioGroup.setOption({ id });
+    } else {
+      console.log('toggle');
+      selected = !selected;
+    }
+
+    ctx.close();
+    dispatch('click');
+  }}"
+>
+  {#if subOptions}
+    <div
+      data-nested="{true}"
+      class:bx--context-menu-option__content="{true}"
+      class:bx--context-menu-option__content--disabled="{disabled}"
+    >
+      {#if indented}
+        <div class:bx--context-menu-option__icon="{true}">
+          <svelte:component this="{icon}" />
+        </div>
+      {/if}
+      <span class:bx--context-menu-option__label="{true}" title="{label}">
+        {label}
+      </span>
+      <div class:bx--context-menu-option__info="{true}"><CaretRight16 /></div>
+    </div>
+
+    <ContextMenu
+      open="{submenuOpen}"
+      x="{submenuPosition[0]}"
+      y="{submenuPosition[1]}"
+    >
+      <slot />
+    </ContextMenu>
+  {:else}
+    <div
+      class:bx--context-menu-option__content="{true}"
+      class:bx--context-menu-option__content--disabled="{disabled}"
+    >
+      {#if indented}
+        <div class:bx--context-menu-option__icon="{true}">
+          <svelte:component this="{icon}" />
+        </div>
+      {/if}
+      <span class:bx--context-menu-option__label="{true}" title="{label}">
+        {label}
+      </span>
+      <div class:bx--context-menu-option__info="{true}">{shortcut}</div>
+    </div>
+  {/if}
+</li>
diff --git a/src/ContextMenu/ContextMenuRadioGroup.svelte b/src/ContextMenu/ContextMenuRadioGroup.svelte
new file mode 100644
index 00000000..5b72f30a
--- /dev/null
+++ b/src/ContextMenu/ContextMenuRadioGroup.svelte
@@ -0,0 +1,24 @@
+<script>
+  export let selectedId = "";
+
+  export let label = "";
+
+  import { setContext } from "svelte";
+  import { writable } from "svelte/store";
+  import ContextMenuGroup from "./ContextMenuGroup.svelte";
+
+  const currentId = writable("");
+
+  setContext("ContextMenuRadioGroup", {
+    currentId,
+    setOption: ({ id }) => {
+      selectedId = id;
+    },
+  });
+
+  $: currentId.set(selectedId);
+</script>
+
+<ContextMenuGroup label="{label}">
+  <slot />
+</ContextMenuGroup>
diff --git a/src/ContextMenu/index.js b/src/ContextMenu/index.js
new file mode 100644
index 00000000..3b04911f
--- /dev/null
+++ b/src/ContextMenu/index.js
@@ -0,0 +1,5 @@
+export { default as ContextMenu } from "./ContextMenu.svelte";
+export { default as ContextMenuDivider } from "./ContextMenuDivider.svelte";
+export { default as ContextMenuGroup } from "./ContextMenuGroup.svelte";
+export { default as ContextMenuOption } from "./ContextMenuOption.svelte";
+export { default as ContextMenuRadioGroup } from "./ContextMenuRadioGroup.svelte";
diff --git a/src/index.js b/src/index.js
index d849dea7..f3a347f4 100644
--- a/src/index.js
+++ b/src/index.js
@@ -4,6 +4,13 @@ export { Breadcrumb, BreadcrumbItem, BreadcrumbSkeleton } from "./Breadcrumb";
 export { Button, ButtonSkeleton, ButtonSet } from "./Button";
 export { Checkbox, CheckboxSkeleton } from "./Checkbox";
 export { ContentSwitcher, Switch } from "./ContentSwitcher";
+export {
+  ContextMenu,
+  ContextMenuDivider,
+  ContextMenuGroup,
+  ContextMenuOption,
+  ContextMenuRadioGroup,
+} from "./ContextMenu";
 export { Copy } from "./Copy";
 export { CopyButton } from "./CopyButton";
 export { ComboBox } from "./ComboBox";