Show interactive menus when no command specified

deps/console-menu/LICENSE.txt

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+MIT License
+
+Copyright (c) 2016 Jason Ginchereau
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

deps/console-menu/README.md

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+# console-menu
+Displays a menu of items in the console and asynchronously waits for the user to select an item. Each item title is prefixed by a hotkey. An item may be selected by typing a hotkey or by using Down/Up arrows followed by Enter.
+```
+.--------------.
+| Example menu |
++--------------+
+| [a] Item A   |
+|  b) Item B   |
+|  c) Item C   |
+|  d) Item D   |
+|  e) Item E   |
+'--\/----------'
+```
+The menu may be scrollable (hinted by `/\` and `\/` indicators). PageUp, PageDown, Home, and End keys are also supported.
+
+## Usage
+The `menu` function takes two parameters: an `items` array and an `options` object.
+
+Each item must be an object with the following properties:
+ * `separator` (boolean): If true, this is a separator item that inserts a blank line into the menu. (All other properties are ignored on separator items.)
+ * `title` (string): Item title text.
+ * `hotkey` (character): Unique item hotkey; must be a single letter, number, or other character. If omitted, the item is only selectable via arrow keys + Enter.
+ * `selected` (boolean) True if this item should initially selected. If unspecified then the first item is initially selected.
+
+Items may have additional user-defined properties, which will be included in the returned result.
+
+The following options are supported:
+ * `header` (string): Optional header text for the menu.
+ * `border` (boolean): True to draw a border around the menu. False for a simpler-looking menu.
+ * `pageSize` (integer): Max number of items to show at a time;  additional items cause the menu to be scrollable. Omitting this value (or specifying 0) disables scrolling.
+ * `helpMessage` (string): Message text to show under the menu.
+
+The return value is a `Promise` that resolves to the chosen item object, or to `null` if the menu was cancelled by pressing Esc or Ctrl-C.
+
+## Example
+```JavaScript
+var menu = require('console-menu');
+menu([
+    { hotkey: '1', title: 'One' },
+    { hotkey: '2', title: 'Two', selected: true },
+    { hotkey: '3', title: 'Three' },
+    { separator: true },
+    { hotkey: '?', title: 'Help' },
+], {
+    header: 'Example menu',
+    border: true,
+}).then(item => {
+    if (item) {
+        console.log('You chose: ' + JSON.stringify(item));
+    } else {
+        console.log('You cancelled the menu.');
+    }
+});
+```

deps/console-menu/console-menu.js

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+const os = require('os');
+const readline = require('readline');
+const keypress = require('keypress');
+
+const defaultHelpMessage =
+    'Type a hotkey or use Down/Up arrows then Enter to choose an item.';
+
+/**
+ * Displays a menu of items in the console and asynchronously waits for the user to select an item.
+ *
+ * @param {any} items Array of menu items, where each item is an object that includes a title
+ * property and optional hotkey property. (Items may include additional user-defined properties.)
+ * @param {any} options Dictionary of options for the menu:
+ *   - header {string}: Header text for the menu.
+ *   - border {boolean}: True to draw a border around the menu.
+ *   - pageSize {integer}: Max number of items to show at a time. Additional items cause the menu
+ *     to be scrollable.
+ *   - helpMessage {string}: Message text to show under the menu.
+ * @returns A promise that resolves to the chosen item, or to null if the menu was cancelled.
+ */
+function menu(items, options) {
+    if (!items || !Array.isArray(items) || items.length < 1) {
+        throw new TypeError('A nonempty items array is required.');
+    }
+    options = options || {};
+
+    var count = items.length;
+    var selectedIndex = items.findIndex(item => item.selected);
+    if (selectedIndex < 0) {
+        selectedIndex = 0;
+        while (selectedIndex < count && items[selectedIndex].separator) selectedIndex++;
+    }
+
+    var scrollOffset = 0;
+    printMenu(items, options, selectedIndex, scrollOffset);
+
+    return new Promise((resolve, reject) => {
+        process.stdin.setRawMode(true);
+        process.stdin.resume();
+        keypress(process.stdin);
+
+        var handleMenuKeypress = (ch, key) => {
+            var selection = null;
+            if (isEnter(key)) {
+                selection = items[selectedIndex];
+            } else if (ch) {
+                selection = items.find(item => item.hotkey && item.hotkey === ch) ||
+                    items.find(item => item.hotkey &&
+                        item.hotkey.toLowerCase() === ch.toLowerCase());
+            }
+
+            var newIndex = null;
+            if (selection || isCancelCommand(key)) {
+                process.stdin.removeListener('keypress', handleMenuKeypress);
+                process.stdin.setRawMode(false);
+                resetCursor(options, selectedIndex, scrollOffset);
+                readline.clearScreenDown(process.stdout);
+                process.stdin.pause();
+                resolve(selection);
+            } else if (isUpCommand(key) && selectedIndex > 0) {
+                newIndex = selectedIndex - 1;
+                while (newIndex >= 0 && items[newIndex].separator) newIndex--;
+            } else if (isDownCommand(key) && selectedIndex < count - 1) {
+                newIndex = selectedIndex + 1;
+                while (newIndex < count && items[newIndex].separator) newIndex++;
+            } else if (isPageUpCommand(key) && selectedIndex > 0) {
+                newIndex = (options.pageSize ? Math.max(0, selectedIndex - options.pageSize) : 0);
+                while (newIndex < count && items[newIndex].separator) newIndex++;
+            } else if (isPageDownCommand(key) && selectedIndex < count - 1) {
+                newIndex = (options.pageSize
+                    ? Math.min(count - 1, selectedIndex + options.pageSize) : count - 1);
+                while (newIndex >= 0 && items[newIndex].separator) newIndex--;
+            } else if (isGoToFirstCommand(key) && selectedIndex > 0) {
+                newIndex = 0;
+                while (newIndex < count && items[newIndex].separator) newIndex++;
+            } else if (isGoToLastCommand(key) && selectedIndex < count - 1) {
+                newIndex = count - 1;
+                while (newIndex >= 0 && items[newIndex].separator) newIndex--;
+            }
+
+            if (newIndex !== null && newIndex >= 0 && newIndex < count) {
+                resetCursor(options, selectedIndex, scrollOffset);
+
+                selectedIndex = newIndex;
+
+                // Adjust the scroll offset when the selection moves off the page.
+                if (selectedIndex < scrollOffset) {
+                    scrollOffset = (isPageUpCommand(key)
+                        ? Math.max(0, scrollOffset - options.pageSize) : selectedIndex);
+                } else if (options.pageSize && selectedIndex >= scrollOffset + options.pageSize) {
+                    scrollOffset = (isPageDownCommand(key)
+                        ? Math.min(count - options.pageSize, scrollOffset + options.pageSize)
+                        : selectedIndex - options.pageSize + 1);
+                }
+
+                printMenu(items, options, selectedIndex, scrollOffset);
+            }
+        };
+
+        process.stdin.addListener('keypress', handleMenuKeypress);
+    });
+}
+
+function isEnter(key) { return key && (key.name === 'enter' || key.name === 'return'); }
+function isUpCommand(key) { return key && key.name === 'up'; }
+function isDownCommand(key) { return key && key.name === 'down'; }
+function isPageUpCommand(key) { return key && key.name === 'pageup'; }
+function isPageDownCommand(key) { return key && key.name === 'pagedown'; }
+function isGoToFirstCommand(key) { return key && key.name === 'home'; }
+function isGoToLastCommand(key) { return key && key.name === 'end'; }
+function isCancelCommand(key) {
+    return key && ((key.ctrl && key.name == 'c') || key.name === 'escape');
+}
+
+function resetCursor(options, selectedIndex, scrollOffset) {
+    readline.moveCursor(process.stdout, -3,
+        - (options.header ? 1 : 0)
+        - (options.border ? (options.header ? 2 : 1) : 0)
+        - selectedIndex + scrollOffset);
+}
+
+function printMenu(items, options, selectedIndex, scrollOffset) {
+    var repeat = (s, n) => {
+        return Array(n + 1).join(s);
+    };
+
+    var width = 0;
+    for (var i = 0; i < items.length; i++) {
+        if (items[i].title && 4 + items[i].title.length > width) {
+            width = 4 + items[i].title.length;
+        }
+    }
+
+    var prefix = (options.border ? '|' : '');
+    var suffix = (options.border ? ' |' : '');
+
+    if (options.header && options.header.length > width) {
+        width = options.header.length;
+    }
+
+    if (options.border) {
+        if (!options.header && options.pageSize && scrollOffset > 0) {
+            process.stdout.write('.--/\\' + repeat('-', width - 2) + '.' + os.EOL);
+        } else {
+            process.stdout.write('.' + repeat('-', width + 2) + '.' + os.EOL);
+        }
+    }
+
+    if (options.header) {
+        process.stdout.write(prefix + (options.border ? ' ' : '') + options.header +
+            repeat(' ', width - options.header.length) + suffix + os.EOL);
+        if (options.border) {
+            if (options.pageSize && scrollOffset > 0) {
+                process.stdout.write('+--/\\' + repeat('-', width - 2) + '+' + os.EOL);
+            } else {
+                process.stdout.write('+' + repeat('-', width + 2) + '+' + os.EOL);
+            }
+        }
+    }
+
+    var scrollEnd = options.pageSize
+        ? Math.min(items.length, scrollOffset + options.pageSize)
+        : items.length;
+    for (var i = scrollOffset; i < scrollEnd; i++) {
+        if (items[i].separator) {
+            process.stdout.write(prefix + ' ' + repeat(' ', width) + suffix + os.EOL);
+        } else {
+            var hotkey = items[i].hotkey || '*';
+            var title = items[i].title || '';
+            var label = (i === selectedIndex
+                ? '[' + hotkey + ']' : ' ' + hotkey + ')');
+            process.stdout.write(prefix + ' ' + label + ' ' + title +
+                repeat(' ', width - title.length - 4) + suffix + os.EOL);
+        }
+    }
+
+    if (options.border) {
+        if (options.pageSize && scrollEnd < items.length) {
+            process.stdout.write('\'--\\/' + repeat('-', width - 2) + '\'' + os.EOL);
+        } else {
+            process.stdout.write('\'' + repeat('-', width + 2) + '\'' + os.EOL);
+        }
+    }
+
+    process.stdout.write(options.helpMessage || defaultHelpMessage);
+    readline.moveCursor(process.stdout,
+        -(options.helpMessage || defaultHelpMessage).length + prefix.length + 2,
+        -(options.border ? 1 : 0) - (scrollEnd - scrollOffset) + selectedIndex - scrollOffset);
+}
+
+module.exports = menu;