Initial commit

ui/commands/color.js

@@ -0,0 +1,107 @@
+// Sshwifty - A Web SSH client
+//
+// Copyright (C) 2019 Rui NI <nirui@gmx.com>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+/**
+ * Get one color hex byte
+ *
+ * @param {number} from Min color number
+ * @param {number} to Max color number
+ *
+ * @returns {string} color byte in string
+ *
+ */
+function getRandHex(from, to) {
+  let color = Math.random() * (to - from) + from,
+    colorDark = color - color / 20;
+
+  let r = Math.round(color).toString(16),
+    rDark = Math.round(colorDark).toString(16);
+
+  if (r.length % 2 !== 0) {
+    r = "0" + r;
+  }
+
+  if (rDark.length % 2 !== 0) {
+    rDark = "0" + rDark;
+  }
+
+  return [r, rDark];
+}
+
+/**
+ * Get rand color
+ *
+ * @param {number} from Min color number
+ * @param {number} to Max color number
+ *
+ * @returns {string} Color bytes in string
+ */
+function getRandColor(from, to) {
+  let r = getRandHex(from, to),
+    g = getRandHex(from, to),
+    b = getRandHex(from, to);
+
+  return ["#" + r[0] + g[0] + b[0], "#" + r[1] + g[1] + b[1]];
+}
+
+export class Color {
+  /**
+   * constructor
+   */
+  constructor() {
+    this.assignedColors = {};
+  }
+
+  /**
+   * Get one color
+   *
+   * @returns {string} Color code
+   *
+   */
+  get() {
+    const maxTries = 10;
+    let tried = 0;
+
+    for (;;) {
+      let color = getRandColor(0x22, 0x33);
+
+      if (this.assignedColors[color[0]]) {
+        tried++;
+
+        if (tried < maxTries) {
+          continue;
+        }
+      }
+
+      this.assignedColors[color[0]] = true;
+
+      return {
+        color: color[0],
+        dark: color[1]
+      };
+    }
+  }
+
+  /**
+   * forget already assigned color
+   *
+   * @param {string} color Color code
+   */
+  forget(color) {
+    delete this.assignedColors[color];
+  }
+}