initial commit

background-script.js

@@ -0,0 +1,141 @@
+'use strict';
+
+// We use JMdict converted to JSON. It's like 32MB so we don't want to load it for every tab.
+// So we need to use a backgroudn script and send messages to it from the content script.
+// Unfortunately webextensions don't have an easy way to load files even from in extension.
+// We have to send an HTTP request and store the result in a string before parsing it into an object.
+// Seriously.
+
+let text = "";
+
+function listener()
+{
+    if (this.readyState === 4)
+    {
+        if (this.status === 200)
+            text = this.responseText;
+        else
+            console.error(xhr.statusText);
+    }
+}
+
+let req = new XMLHttpRequest();
+req.addEventListener("load", listener);
+// FIXME: apparently this has to be in an async function now.
+req.open("GET", browser.extension.getURL("dict/JMdict.json"), false);
+req.send();
+
+let dict = JSON.parse(text);
+text = "";
+
+// Build map of spellings to dictionary entry.
+
+let lookup_kan = {};
+let lookup_kana = {};
+
+for (let i = 0; i < dict.length; i++)
+{
+    let entry = dict[i];
+    if (entry.k_ele != undefined) for (let j = 0; j < entry.k_ele.length; j++)
+    {
+        let s = entry.k_ele[j];
+        if (lookup_kan[s.keb] == undefined)
+            lookup_kan[s.keb] = [i];
+        else
+            lookup_kan[s.keb].push(i);
+    }
+    for (let j = 0; j < entry.r_ele.length; j++)
+    {
+        let s = entry.r_ele[j];
+        if (lookup_kana[s.reb] == undefined)
+            lookup_kana[s.reb] = [i];
+        else
+            lookup_kana[s.reb].push(i);
+    }
+}
+for (let i = 0; i < 5; i++)
+{
+    console.log(dict[i]);
+}
+console.log("built lookup tables");
+console.log("size:");
+console.log(Object.keys(lookup_kan).length);
+console.log(Object.keys(lookup_kana).length);
+console.log("dict size:");
+console.log(dict.length);
+
+// In JMdict, part-of-speech tags are XML entities.
+// We processed JMdict's XML with entity processing disabled so we can just use the bare tags (e.g. "v1", not "ichidan verb").
+// This left the entity syntax &this; behind so we want to cut it off when we return results.
+function clip(str)
+{
+    if(str == undefined)
+        return;
+    if(str.length <= 2)
+        return "";
+    return str.substring(1, str.length-1);
+}
+
+function getfromdict(indexes)
+{
+    let ret = [];
+    for(let i = 0; i < indexes.length; i++)
+    {
+        let entry = dict[indexes[i]];
+        let lastpos = [];
+        // JMdict tags part-of-speech for senses sparsely
+        // e.g. if 1. and 2. share the same list of POSs, only 1. will have a POS list
+        // undoing this here makes things in the content script WAY less inconvenient
+        for(let j = 0; j < entry.sense.length; j++)
+        {
+            if(entry.sense[j].pos)
+            {
+                for(let t = 0; t < entry.sense[j].pos.length; t++)
+                {
+                    if(entry.sense[j].pos[t].charAt(0)=="&")
+                        entry.sense[j].pos[t] = clip(entry.sense[j].pos[t]);
+                }
+            }
+            else
+                entry.sense[j].pos = lastpos;
+            lastpos = entry.sense[j].pos;
+        }
+        ret.push(entry);
+    }
+    return ret;
+}
+
+function search(text)
+{
+    if (lookup_kan[text])
+    {
+        //console.log("search successful (kanji)");
+        return getfromdict(lookup_kan[text]);
+    }
+    else if (lookup_kana[text])
+    {
+        //console.log("search successful (kana)");
+        return getfromdict(lookup_kana[text]);
+    }
+    else
+    {
+        //console.log("search failed");
+        //console.log(text);
+        return;
+    }
+}
+
+browser.runtime.onMessage.addListener((request, sender, sendResponse) => {
+    if (request.type == 'search')
+    {
+        //console.log("running search");
+        sendResponse(search(request.text));
+    }
+    else
+    {
+        //console.log("unhandled request");
+        //return;
+        return;
+    }
+});
+