Simplify working with columns

docs/demos/kitchen-sink/demo/demo-a.md

@@ -77,7 +77,7 @@ import { tracked } from '@glimmer/tracking';
 import { htmlSafe } from '@ember/template';
 
 import { headlessTable } from 'ember-headless-table';
-import { meta } from 'ember-headless-table/plugins';
+import { meta, columns } from 'ember-headless-table/plugins';
 import {
   ColumnResizing,
   isResizing, resizeHandle
@@ -139,7 +139,7 @@ export default class extends Component {
   @tracked sorts = [];
 
   get columns() {
-    return meta.forTable(this.table, ColumnReordering).columns;
+    return columns.for(this.table);
   }
 
   get data() {

docs/plugins/column-reordering/demo/dema-a.md

@@ -34,12 +34,11 @@
 import Component from '@glimmer/component';
 
 import { headlessTable } from 'ember-headless-table';
-import { meta } from 'ember-headless-table/plugins';
+import { meta, columns } from 'ember-headless-table/plugins';
 import {
   ColumnReordering,
   moveLeft, moveRight
 } from 'ember-headless-table/plugins/column-reordering';
-import { ColumnVisibility } from 'ember-headless-table/plugins/column-visibility';
 
 import { DATA } from 'docs-app/sample-data';
 
@@ -54,12 +53,11 @@ export default class extends Component {
     data: () => DATA,
     plugins: [
       ColumnReordering,
-      ColumnVisibility,
     ],
   });
 
   get columns() {
-    return meta.forTable(this.table, ColumnReordering).columns;
+    return columns.for(this.table);
   }
 
   /**

docs/plugins/column-resizing/demo/demo-a.md

@@ -62,8 +62,6 @@ export default class extends Component {
     ],
     data: () => DATA,
     plugins: [
-      ColumnVisibility,
-      ColumnReordering,
       ColumnResizing,
     ],
   });

docs/plugins/column-resizing/index.md

@@ -6,21 +6,16 @@ API Documentation available [here][api-docs]
 
 ## Usage
 
-Because this plugin operates or visible columns,
-the `ColumnVisibility` plugin is required.
-
 ```js
 import { headlessTable } from 'ember-headless-table';
 import { ColumnResizing, resizeHandle } from 'ember-headless-table/plugins/column-resizing';
-import { ColumnVisibility } from 'ember-headless-table/plugins/column-visibility';
 
 // ...
 // in a class
   table = headlessTable(this, {
     columns: () => [ /* ... */ ],
     data: () => [ /* ... */ ],
     plugins: [
-      ColumnVisibility,
       ColumnResizing,
     ],
   })
@@ -55,7 +50,6 @@ See the API Documentation [here][api-docs] for the full list of options and desc
 table = headlessTable(this, {
   columns: () => [ /* ... */ ],
   plugins: [
-    ColumnVisibility,
     ColumnResizing.with(() => ({ handlePosition: 'right' })),
   ],
 })

docs/plugins/column-visibility/demo/demo-a.md

@@ -45,7 +45,7 @@
 import Component from '@glimmer/component';
 
 import { headlessTable } from 'ember-headless-table';
-import { meta } from 'ember-headless-table/plugins';
+import { meta, columns } from 'ember-headless-table/plugins';
 import { ColumnVisibility, hide, show } from 'ember-headless-table/plugins/column-visibility';
 
 import { DATA } from 'docs-app/sample-data';
@@ -65,7 +65,7 @@ export default class extends Component {
   });
 
   get columns() {
-    return meta.forTable(this.table, ColumnVisibility).visibleColumns;
+    return columns.for(this.table);
   }
 
   /**

docs/plugins/sticky-column/demo/demo-a.md

@@ -59,7 +59,6 @@ export default class extends Component {
     plugins: [
       StickyColumns,
       ColumnResizing,
-      ColumnVisibility,
     ],
   });
 

docs/plugins/sticky-column/index.md

@@ -8,7 +8,6 @@ API Documentation available [here][api-docs]
 
 ```js
 import { headlessTable } from 'ember-headless-table';
-import { ColumnVisibility } from 'ember-headless-table/plugins/column-visibility';
 import { StickyColumns } from 'ember-headless-table/plugins/sticky-columns';
 import { ColumnResizing } from 'ember-headless-table/plugins/column-resizing';
 
@@ -26,13 +25,16 @@ import { ColumnResizing } from 'ember-headless-table/plugins/column-resizing';
     ],
     data: () => [ /* ... */ ],
     plugins: [
-      ColumnReordering,
-      ColumnVisibility,
+      ColumnResizing,
       StickyColumns,
     ],
   })
 ```
 
+Note that the `ColumnResizing` plugin is required because `StickyColumns` needs a guarantee
+that a `columnWidth` implementation exists so that columns may become sticky beyond just the
+far left and far right columns.
+
 ### ColumnOptions
 
 - `sticky`

docs/plugins/writing-your-own.md

@@ -31,6 +31,7 @@ The key properties to look at are:
   - `headerCellModifier` - for each `<th>`
   - `rowModifier` - for each `<tr>`
 - `reset` -- a hook that the table will call on your plugin if you have state to revert to
+- `columns` -- for overriding / altering column order / visibility / grouping / etc
 
 With these capabilities, features for tables may be built in a way that relieves implementation complexity on the consumer, such as:
 

ember-headless-table/src/-private/interfaces/plugins.ts

@@ -171,6 +171,23 @@ export interface Plugin<Signature = unknown> {
    * If the plugin has state, this should be used to reset that state
    */
   reset?: () => void;
+
+  /**
+   * @public
+   * @kind Table Hook
+   *
+   * A plugin may change the columns order, visibility, etc.
+   * By implementing this getter, this plugin's
+   * `columns` property will be used by other plugins via
+   * the `columns.for(table, RequestingPlugin)` api.
+   *
+   * For the end-consumer, they may choose to do
+   * `columns.for(table)`, which will aggregate all column modifications
+   * from all plugins.
+   *
+   * As always, `table.columns` is the way to get the unmodified list of columns.
+   */
+  columns?: Column<any>[];
 }
 
 /**

ember-headless-table/src/-private/table.ts

@@ -205,6 +205,8 @@ export class Table<DataType = unknown> extends Resource<Signature<DataType>> {
 
   /**
    * @private
+   *
+   * used by other private APIs
    */
   get config() {
     return this.args.named;
@@ -234,15 +236,6 @@ export class Table<DataType = unknown> extends Resource<Signature<DataType>> {
     },
   });
 
-  /**
-   * @private
-   *
-   * TODO: what's this for?
-   */
-  get value() {
-    return this;
-  }
-
   /**
    * @private
    */

ember-headless-table/src/plugins/-private/base.ts

@@ -227,6 +227,197 @@ export const preferences = {
   },
 };
 
+/**
+ * if a `requester` is not provided,
+ * Get the columns for the table, considering any and all plugins that could modify columns.
+ *
+ * If you are an end-consumer of ember-headless-table, this is the function to use.
+ * If you are a plugin-author, you'll want to pass your plugin class as the second parameter.
+ *
+ * For a given plugin, `requester`, determine what columns should be returned.
+ * Since multiple plugins could be used in a table, there is an implicit hierarchy of
+ * column modifications that can occur from each of those plugins.
+ *
+ * If a plugin defines other plugins as either *requirements* or *optional requirements*,
+ * and that upstream plugin defines a `columns` property, then those columns will be returned here.
+ *
+ * This works recursively up the plugin tree up until a plugin has no requirements, and then
+ * all columns from the table are returned.
+ */
+function columnsFor<DataType = any>(
+  table: Table<DataType>,
+  requester?: Plugin<any> | undefined
+): Column<DataType>[] {
+  assert(`First argument passed to columns.for must be an instance of Table`, table[TABLE_KEY]);
+
+  let visibility = findPlugin(table.plugins, 'columnVisibility');
+  let reordering = findPlugin(table.plugins, 'columnOrder');
+
+  // TODO: actually resolve the graph, rather than use the hardcoded feature names
+  //       atm, this only "happens" to work based on expectations of
+  //       of the currently implemented plugins' capabilities and implied hierarchy.
+
+  if (requester) {
+    assert(
+      `[${requester.name}] requested columns from the table, but the plugin, ${requester.name}, ` +
+        `is not used in this table`,
+      table.plugins.some((plugin) => plugin instanceof (requester as Class<Plugin>))
+    );
+
+    if (visibility && visibility.constructor === requester) {
+      return table.columns.values();
+    }
+
+    if (reordering && reordering.constructor === requester) {
+      if (visibility) {
+        assert(
+          `<#${visibility.name}> defined a 'columns' property, but did not return valid data.`,
+          visibility.columns && Array.isArray(visibility.columns)
+        );
+
+        return visibility.columns;
+      }
+
+      return table.columns.values();
+    }
+
+    if (reordering) {
+      assert(
+        `<#${reordering.name}> defined a 'columns' property, but did not return valid data.`,
+        reordering.columns && Array.isArray(reordering.columns)
+      );
+
+      return reordering.columns;
+    }
+
+    if (visibility) {
+      assert(
+        `<#${visibility.name}> defined a 'columns' property, but did not return valid data.`,
+        visibility.columns && Array.isArray(visibility.columns)
+      );
+
+      return visibility.columns;
+    }
+
+    return table.columns.values();
+  }
+
+  /**
+   * This flow is the inverse of when we have a requester
+   */
+
+  if (reordering) {
+    assert(
+      `<#${reordering.name}> defined a 'columns' property, but did not return valid data.`,
+      reordering.columns && Array.isArray(reordering.columns)
+    );
+
+    return reordering.columns;
+  }
+
+  if (visibility) {
+    assert(
+      `<#${visibility.name}> defined a 'columns' property, but did not return valid data.`,
+      visibility.columns && Array.isArray(visibility.columns)
+    );
+
+    return visibility.columns;
+  }
+
+  return table.columns.values();
+}
+
+export const columns = {
+  for: columnsFor,
+
+  /**
+   * for a given current or reference column, return the column that
+   * is immediately next, or to the right of that column.
+   *
+   * If a plugin class is provided, the hierarchy of column list modifications
+   * will be respected.
+   */
+  next: <Data = unknown>(
+    current: Column<Data>,
+    requester?: Plugin<any>
+  ): Column<Data> | undefined => {
+    let columns = requester ? columnsFor(current.table, requester) : columnsFor(current.table);
+
+    let referenceIndex = columns.indexOf(current);
+
+    assert(
+      `index of reference column must be >= 0. column likely not a part of the table`,
+      referenceIndex >= 0
+    );
+
+    /**
+     * There can be nothing after the last column
+     */
+    if (referenceIndex >= columns.length - 1) {
+      return undefined;
+    }
+
+    return columns[referenceIndex + 1];
+  },
+
+  /**
+   * for a given current or reference column, return the column that
+   * is immediately previous, or to the left of that column.
+   *
+   * If a plugin class is provided, the hierarchy of column list modifications
+   * will be respected.
+   */
+  previous: <Data = unknown>(
+    current: Column<Data>,
+    requester?: Plugin<any>
+  ): Column<Data> | undefined => {
+    let columns = requester ? columnsFor(current.table, requester) : columnsFor(current.table);
+    let referenceIndex = columns.indexOf(current);
+
+    assert(
+      `index of reference column must be >= 0. column likely not a part of the table`,
+      referenceIndex >= 0
+    );
+
+    /**
+     * There can be nothing before the first column
+     */
+    if (referenceIndex === 0) {
+      return undefined;
+    }
+
+    return columns[referenceIndex - 1];
+  },
+  /**
+   * for a given current or reference column, return the columns that
+   * should appear before, or to the left of that column.
+   *
+   * if a plugin class is provided, the hierarchy of column list modifications
+   * will be respected.
+   */
+  before: <Data = unknown>(current: Column<Data>, requester?: Plugin<any>): Column<Data>[] => {
+    let columns = requester ? columnsFor(current.table, requester) : columnsFor(current.table);
+
+    let referenceIndex = columns.indexOf(current);
+
+    return columns.slice(0, referenceIndex);
+  },
+  /**
+   * for a given current or reference column, return the columns that
+   * should appear after, or to the right of that column.
+   *
+   * if a plugin class is provided, the hierarchy of column list modifications
+   * will be respected.
+   */
+  after: <Data = unknown>(current: Column<Data>, requester?: Plugin<any>): Column<Data>[] => {
+    let columns = requester ? columnsFor(current.table, requester) : columnsFor(current.table);
+
+    let referenceIndex = columns.indexOf(current);
+
+    return columns.slice(referenceIndex + 1);
+  },
+};
+
 export const meta = {
   /**
    * @public