From 801bac60f56ac64e75b18a25fb97713cb118b32b Mon Sep 17 00:00:00 2001
From: Rokas Puzonas <rokas.puz@gmail.com>
Date: Thu, 18 May 2023 19:41:50 +0300
Subject: [PATCH] initial commit

---
 README.md        |  3 ++
 contentScript.js | 96 ++++++++++++++++++++++++++++++++++++++++++++++++
 manifest.json    | 14 +++++++
 3 files changed, 113 insertions(+)
 create mode 100644 README.md
 create mode 100644 contentScript.js
 create mode 100644 manifest.json

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..5489ea7
--- /dev/null
+++ b/README.md
@@ -0,0 +1,3 @@
+# Metric unit converter for allrecipes.com
+
+Converts *most* imperial units to metric units for https://www.allrecipes.com
\ No newline at end of file
diff --git a/contentScript.js b/contentScript.js
new file mode 100644
index 0000000..eb71d87
--- /dev/null
+++ b/contentScript.js
@@ -0,0 +1,96 @@
+
+const imperialUnitNames = ["cup", "ounce", "teaspoon", "pound"];
+
+function findImperialUnitIndex(text) {
+    return imperialUnitNames.findIndex(unitName => text.includes(unitName))
+}
+
+function textToNumber(text) {
+    if (text == "¼") {
+        return 0.25
+    } else if (text == "½") {
+        return 0.5
+    } else if (text.includes("/")) {
+        const [beforeSlash, afterSlash] = text.split("/")
+        return Number(beforeSlash) / Number(afterSlash)
+    } else {
+        return Number(text)
+    }
+}
+
+function convertUnits(amount, unitName) {
+    if (unitName.includes("cup")) {
+        amount = textToNumber(amount)
+        const mlAmount = Math.round(amount*236.5882365)
+        const gramsAmount = Math.round(amount*201.6)
+        return ["~" + mlAmount, "ml or (~" + gramsAmount + " g)" ]
+
+    } else if (unitName.includes("teaspoon")) {
+        amount = textToNumber(amount)
+        const mlAmount = Math.round(amount*5.919388)
+        const gramsAmount = Math.round(amount*4.2605668424239)
+        return ["~" + mlAmount, "ml or (~" + gramsAmount + " g)" ]
+
+    } else if (unitName.includes("pound")) {
+        return ["~" + Math.round(amount*453.59237), "grams"]
+
+    } else if (unitName.includes("ounce")) {
+        //amount = textToNumber(amount)
+        //const gramsAmount = Math.fround(amount * 28.34952);
+        return [amount, unitName]
+        //return ["~" + , "grams"]
+
+    } else {
+        return [amount, unitName]
+    }
+}
+
+function textNodesUnder(node) {
+    var n, a=[], walk=document.createTreeWalker(node,NodeFilter.SHOW_ELEMENT | NodeFilter.SHOW_TEXT,null,false)
+    while(n=walk.nextNode()) a.push(n)
+    return a
+}
+
+function replaceImperialUnitsInText(text) {
+    const words = text.split(" ")
+    for (let i = 1; i < words.length; i++) {
+        if (findImperialUnitIndex(words[i]) != -1) {
+            const [newAmount, newUnitName] = convertUnits(words[i-1], words[i]);
+            words[i-1] = newAmount
+            words[i] = newUnitName
+            updated = true
+        }
+    }
+
+    return words.join(" ")
+}
+
+const content = document.getElementsByClassName("loc article-content")[0]
+for (const textNode of textNodesUnder(content)) {
+    if (!textNode.parentElement) continue;
+
+    if (textNode.parentElement.classList.contains("mntl-structured-ingredients__list-item")) {
+        let quantityChild;
+        let unitNameChild;
+        for (const child of textNode.childNodes) {
+            if (!child.dataset) continue
+
+            if ("ingredientQuantity" in child.dataset) {
+                quantityChild = child
+            } else if ("ingredientUnit" in child.dataset) {
+                unitNameChild = child
+            }
+        }
+        if (unitNameChild && quantityChild && quantityChild.textContent.length > 0) {
+            if (findImperialUnitIndex(unitNameChild.textContent) == 0) {
+                const [newAmount, newUnitName] = convertUnits(quantityChild.textContent, unitNameChild.textContent);
+                quantityChild.textContent = newAmount
+                unitNameChild.textContent = newUnitName
+            } else {
+
+            }
+        }
+    } else if (textNode.nodeValue && findImperialUnitIndex(textNode.nodeValue) != -1) {
+        textNode.nodeValue = replaceImperialUnitsInText(textNode.nodeValue)
+    }
+}
diff --git a/manifest.json b/manifest.json
new file mode 100644
index 0000000..629c5e3
--- /dev/null
+++ b/manifest.json
@@ -0,0 +1,14 @@
+{
+    "name": "Allrecipes.com metric units converter",
+    "version": "0.1.0",
+    "description": "Convert all imperial units on page to metric.",
+    "permissions": ["storage", "tabs"],
+    "host_permissions": ["https://*.allrecipes.com/*"],
+    "content_scripts": [
+      {
+        "matches": ["https://*.allrecipes.com/recipe/*"],
+        "js": ["contentScript.js"]
+      }
+    ],
+    "manifest_version": 3
+}