1 files changed, 248 insertions, 0 deletions
diff --git a/node_modules/postcss-normalize-positions/src/index.js b/node_modules/postcss-normalize-positions/src/index.js
new file mode 100644
index 00000000..66e99061
--- /dev/null
+++ b/node_modules/postcss-normalize-positions/src/index.js
@@ -0,0 +1,248 @@
+'use strict';
+const valueParser = require('postcss-value-parser');
+
+const directionKeywords = new Set(['top', 'right', 'bottom', 'left', 'center']);
+
+const center = '50%';
+const horizontal = new Map([
+  ['right', '100%'],
+  ['left', '0'],
+]);
+const verticalValue = new Map([
+  ['bottom', '100%'],
+  ['top', '0'],
+]);
+const mathFunctions = new Set(['calc', 'min', 'max', 'clamp']);
+const variableFunctions = new Set(['var', 'env', 'constant']);
+/**
+ * @param {valueParser.Node} node
+ * @return {boolean}
+ */
+function isCommaNode(node) {
+  return node.type === 'div' && node.value === ',';
+}
+
+/**
+ * @param {valueParser.Node} node
+ * @return {boolean}
+ */
+function isVariableFunctionNode(node) {
+  if (node.type !== 'function') {
+    return false;
+  }
+
+  return variableFunctions.has(node.value.toLowerCase());
+}
+
+/**
+ * @param {valueParser.Node} node
+ * @return {boolean}
+ */
+function isMathFunctionNode(node) {
+  if (node.type !== 'function') {
+    return false;
+  }
+  return mathFunctions.has(node.value.toLowerCase());
+}
+
+/**
+ * @param {valueParser.Node} node
+ * @return {boolean}
+ */
+function isNumberNode(node) {
+  if (node.type !== 'word') {
+    return false;
+  }
+
+  const value = parseFloat(node.value);
+
+  return !isNaN(value);
+}
+
+/**
+ * @param {valueParser.Node} node
+ * @return {boolean}
+ */
+function isDimensionNode(node) {
+  if (node.type !== 'word') {
+    return false;
+  }
+
+  const parsed = valueParser.unit(node.value);
+
+  if (!parsed) {
+    return false;
+  }
+
+  return parsed.unit !== '';
+}
+
+/**
+ * @param {string} value
+ * @return {string}
+ */
+function transform(value) {
+  const parsed = valueParser(value);
+  /** @type {({start: number, end: number} | {start: null, end: null})[]} */
+  const ranges = [];
+  let rangeIndex = 0;
+  let shouldContinue = true;
+
+  parsed.nodes.forEach((node, index) => {
+    // After comma (`,`) follows next background
+    if (isCommaNode(node)) {
+      rangeIndex += 1;
+      shouldContinue = true;
+
+      return;
+    }
+
+    if (!shouldContinue) {
+      return;
+    }
+
+    // After separator (`/`) follows `background-size` values
+    // Avoid them
+    if (node.type === 'div' && node.value === '/') {
+      shouldContinue = false;
+
+      return;
+    }
+
+    if (!ranges[rangeIndex]) {
+      ranges[rangeIndex] = {
+        start: null,
+        end: null,
+      };
+    }
+
+    // Do not try to be processed `var and `env` function inside background
+    if (isVariableFunctionNode(node)) {
+      shouldContinue = false;
+      ranges[rangeIndex].start = null;
+      ranges[rangeIndex].end = null;
+
+      return;
+    }
+
+    const isPositionKeyword =
+      (node.type === 'word' &&
+        directionKeywords.has(node.value.toLowerCase())) ||
+      isDimensionNode(node) ||
+      isNumberNode(node) ||
+      isMathFunctionNode(node);
+
+    if (ranges[rangeIndex].start === null && isPositionKeyword) {
+      ranges[rangeIndex].start = index;
+      ranges[rangeIndex].end = index;
+
+      return;
+    }
+
+    if (ranges[rangeIndex].start !== null) {
+      if (node.type === 'space') {
+        return;
+      } else if (isPositionKeyword) {
+        ranges[rangeIndex].end = index;
+
+        return;
+      }
+
+      return;
+    }
+  });
+
+  ranges.forEach((range) => {
+    if (range.start === null) {
+      return;
+    }
+
+    const nodes = parsed.nodes.slice(range.start, range.end + 1);
+
+    if (nodes.length > 3) {
+      return;
+    }
+
+    const firstNode = nodes[0].value.toLowerCase();
+    const secondNode =
+      nodes[2] && nodes[2].value ? nodes[2].value.toLowerCase() : null;
+
+    if (nodes.length === 1 || secondNode === 'center') {
+      if (secondNode) {
+        nodes[2].value = nodes[1].value = '';
+      }
+
+      const map = new Map([...horizontal, ['center', center]]);
+
+      if (map.has(firstNode)) {
+        nodes[0].value = /** @type {string}*/ (map.get(firstNode));
+      }
+
+      return;
+    }
+
+    if (secondNode !== null) {
+      if (firstNode === 'center' && directionKeywords.has(secondNode)) {
+        nodes[0].value = nodes[1].value = '';
+
+        if (horizontal.has(secondNode)) {
+          nodes[2].value = /** @type {string} */ (horizontal.get(secondNode));
+        }
+        return;
+      }
+
+      if (horizontal.has(firstNode) && verticalValue.has(secondNode)) {
+        nodes[0].value = /** @type {string} */ (horizontal.get(firstNode));
+        nodes[2].value = /** @type {string} */ (verticalValue.get(secondNode));
+
+        return;
+      } else if (verticalValue.has(firstNode) && horizontal.has(secondNode)) {
+        nodes[0].value = /** @type {string} */ (horizontal.get(secondNode));
+        nodes[2].value = /** @type {string} */ (verticalValue.get(firstNode));
+
+        return;
+      }
+    }
+  });
+
+  return parsed.toString();
+}
+
+/**
+ * @type {import('postcss').PluginCreator<void>}
+ * @return {import('postcss').Plugin}
+ */
+function pluginCreator() {
+  return {
+    postcssPlugin: 'postcss-normalize-positions',
+
+    OnceExit(css) {
+      const cache = new Map();
+
+      css.walkDecls(
+        /^(background(-position)?|(-\w+-)?perspective-origin)$/i,
+        (decl) => {
+          const value = decl.value;
+
+          if (!value) {
+            return;
+          }
+
+          if (cache.has(value)) {
+            decl.value = cache.get(value);
+
+            return;
+          }
+
+          const result = transform(value);
+
+          decl.value = result;
+          cache.set(value, result);
+        }
+      );
+    },
+  };
+}
+
+pluginCreator.postcss = true;
+module.exports = pluginCreator;