5 files changed, 206 insertions, 0 deletions
diff --git a/apps/Calculator/components/App.js b/apps/Calculator/components/App.js
new file mode 100644
index 0000000..df46751
--- /dev/null
+++ b/apps/Calculator/components/App.js
@@ -0,0 +1,109 @@
+import { useState } from 'react';
+import styles from '../styles/Calculator.module.scss'
+
+const App = () => {
+  const [display, setDisplay] = useState('0')
+  const [memory, setMemory] = useState([])
+  const [result, setResult] = useState([])
+
+  const onClear = () => {
+    setDisplay('0')
+    setMemory([])
+  }
+  const onNumber = n => setDisplay(p => display === '0' ? n.toString() : p+n)
+  const onMath = m => {
+    if (display !== '0') {
+      if (!result) {
+        setMemory(p => [
+          ...p,
+          { type: 'n', value: display },
+          { type: 'm', value: m },
+        ]);
+      } else {
+        setResult(false)
+        setMemory([
+          { type: 'n', value: display },
+          { type: 'm', value: m },
+        ]);
+      }
+      setDisplay('0')
+    } else if (memory[memory.length - 1].type === 'm') {
+      setMemory(p => [...p.slice(0, -1), { type: 'm', value: m }]);
+    }
+  }
+
+  const newVal = (prevVal, curVal) => {
+    if (!prevVal || !prevVal.m) return 0;
+
+    if (prevVal.m === '+') {
+      return `${Number(prevVal.value) + Number(curVal.value)}`
+    }
+    if (prevVal.m === '-') {
+      return `${Number(prevVal.value) - Number(curVal.value)}`
+    }
+    if (prevVal.m === '*') {
+      return `${Number(prevVal.value) * Number(curVal.value)}`
+    }
+    if (prevVal.m === '/') {
+      return prevVal.value !== '0' && curVal.value !== '0'
+        ? `${Number(prevVal.value) / Number(curVal.value)}`
+        : '0'
+    }
+  }
+
+  const onResult = () => {
+    if (memory.length > 2 || (memory.length > 1 && display !== '0')) {
+      const actions = display === 0
+        ? memory
+        : [...memory, { type: 'n', value: display }]
+      const result = actions.reduce((prevVal, curVal) => {
+        return curVal.type === 'n'
+          ? ({ value: newVal(prevVal, curVal), m: null })
+          : ({ value: prevVal.value, m: curVal.value })
+      })
+      setDisplay(result?.value || 0);
+      setResult(true)
+      if (display !== 0) {
+        setMemory(p => [...p, { type: 'n', value: display }])
+      }
+    }
+  }
+
+  return (
+    <>
+      <div className='window__submenu'>
+        <div>
+          <div onClick={onClear}>
+            Clear
+          </div>
+        </div>
+      </div>
+      <div className={styles.calculator}>
+        <div className={styles.display}>
+          <div>
+            { memory.map(o => o.value).join(' ') }
+          </div>
+          <div>
+            {display}
+          </div>
+        </div>
+        <div className={styles.keys}>
+          <div>
+            { [...Array(10).keys()].map(k => (
+              <div key={k} onClick={() => onNumber(k)}>{k}</div>
+            )) }
+            <div onClick={() => setDisplay(p => p+'.')}>.</div>
+            <div onClick={onResult}>=</div>
+          </div>
+          <div>
+            {['+','-','*','/'].map(m => (
+              <div key={m} onClick={() => onMath(m)}>{m}</div>
+            ))}
+          </div>
+        </div>
+      </div>
+    </>
+  )
+}
+
+export default App
diff --git a/apps/Calculator/index.js b/apps/Calculator/index.js
new file mode 100644
index 0000000..4a7ef43
--- /dev/null
+++ b/apps/Calculator/index.js
@@ -0,0 +1,3 @@
+import Calculator from './components/App'
+
+export default Calculator
diff --git a/apps/Calculator/styles/Calculator.module.scss b/apps/Calculator/styles/Calculator.module.scss
new file mode 100644
index 0000000..2bc25fa
--- /dev/null
+++ b/apps/Calculator/styles/Calculator.module.scss
@@ -0,0 +1 @@
+@import "calculator";
diff --git a/apps/Calculator/styles/_calculator.scss b/apps/Calculator/styles/_calculator.scss
new file mode 100644
index 0000000..987a0ea
--- /dev/null
+++ b/apps/Calculator/styles/_calculator.scss
@@ -0,0 +1,92 @@
+.calculator {
+  width: 100%;
+  height: 100%;
+  position: relative;
+  background-color: #000;
+  display: flex;
+  flex-direction: column;
+  background-color: var(--color-window-content);
+}
+
+.display {
+  height: 20%;
+  background-color: var(--color-text);
+  color: var(--color-window-content);
+  display: flex;
+  flex-direction: column;
+  padding-right: 1em;
+
+  > div:nth-child(1) {
+    font-size: 1em;
+    padding-top: .5em;
+    white-space: nowrap;
+    text-align: right;
+  }
+
+  > div:nth-child(2) {
+    font-size: 2.5em;
+    flex-grow: 1;
+    display: flex;
+    align-items: center;
+    justify-content: flex-end;
+  }
+}
+
+.keys {
+  height: 80%;
+  width: 100%;
+  display: flex;
+
+  & > div {
+    height: 100%;
+    display: flex;
+
+    & > div {
+      height: 25%;
+      display: flex;
+      justify-content: center;
+      align-items: center;
+      border: 1px solid var(--color-window-buttons);
+      transition: .3s background-color;
+      font-size: 2em;
+    }
+
+    &:nth-of-type(1) {
+      width: 75%;
+      flex-wrap: wrap;
+      background-color: var(--color-window-popup);
+
+      & > div {
+        width: 33.3%;
+        flex-grow: 1;
+
+        &:hover {
+          background-color: var(--color-window-content);
+        }
+
+        &:first-of-type {
+          order: 2;
+        }
+
+        &:nth-of-type(12) {
+          order: 3;
+        }
+      }
+    }
+
+    &:nth-of-type(2) {
+      width: 25%;
+      flex-direction: column;
+
+      & > div {
+        width: 100%;
+        background-color: var(--color-window-menu-alt);
+
+        &:hover {
+          background-color: var(--color-window-content);
+        }
+      }
+    }
+  }
+
+}
diff --git a/apps/index.js b/apps/index.js
index 465761b..eccedac 100644
--- a/apps/index.js
+++ b/apps/index.js
@@ -1,3 +1,4 @@
+export { default as Calculator } from './Calculator'
 export { default as Notes } from './Notes'
 export { default as Player } from './Player'
 export { default as Settings } from './Settings'