From 572ad0f9cffa4d22f465073e52459c58c927c58f Mon Sep 17 00:00:00 2001
From: "Michael J. Radwin" <michael@radwin.org>
Date: Wed, 17 Jul 2024 10:06:08 -0700
Subject: [PATCH] More precise comparison between Israel and Diaspora triennial
 schedules

---
 src/sedrot.js           | 68 +++++++++++++++++++++++++++++++++--------
 views/parsha-detail.ejs | 10 +++---
 2 files changed, 61 insertions(+), 17 deletions(-)

diff --git a/src/sedrot.js b/src/sedrot.js
index 2d25e9e..d1066b0 100644
--- a/src/sedrot.js
+++ b/src/sedrot.js
@@ -163,9 +163,9 @@ export async function parshaDetail(ctx) {
   makePrevNext(parsha, date, hd, il);
   const hasTriennial = hyear >= 5744;
   const triennial = hasTriennial ? makeTriennial(parsha, date, parshaEv, hyear, il) : {};
-  const titleYear = date ? ' ' + hyear : '';
   const [israelDiasporaDiffer, otherLocationAnchor, otherLocationParsha] =
-    doIsraelDiasporaDiffer(parsha, il, hd, triennial.variation);
+    doIsraelDiasporaDiffer(parsha, il, hd, triennial);
+  const title = makeTitle(parsha, date ? hyear : 0, israelDiasporaDiffer, il);
   const translations0 = Object.keys(langNames)
       .map((lang) => {
         const str = Locale.lookupTranslation(parsha.name, lang);
@@ -185,11 +185,11 @@ export async function parshaDetail(ctx) {
   // doubled parsha overwrites first half
   Object.assign(commentary, drash[parsha.name]);
   await ctx.render('parsha-detail', {
-    title: `${parsha.name}${titleYear} - Torah Portion - Hebcal`,
+    title,
     parsha,
     parshaName: parsha.name.replace(/'/g, '’'),
     parshaAnchor,
-    parshaDateAnchor: getParshaDateAnchor(parshaEv).anchor + iSuffix,
+    parshaDateAnchor: getParshaDateAnchor(parshaEv).anchor,
     reading,
     il,
     iSuffix,
@@ -210,6 +210,18 @@ export async function parshaDetail(ctx) {
   });
 }
 
+function makeTitle(parsha, hyear, israelDiasporaDiffer, il) {
+  let title = parsha.name;
+  if (hyear) {
+    title += ' ' + hyear;
+  }
+  if (israelDiasporaDiffer) {
+    title += ' - ' + (il ? 'Israel' : 'Diaspora');
+  }
+  title += ' - Torah Portion - Hebcal';
+  return title;
+}
+
 function makeReading(date, parshaEv, il, parshaName) {
   const reading = date ?
     getLeyningForParshaHaShavua(parshaEv, il) :
@@ -252,16 +264,39 @@ function getRawTriennial(parshaName, hd, il) {
   return reading;
 }
 
+function doTriennialDiffer(a, b) {
+  if (a.variation !== b.variation) {
+    return true;
+  }
+  if (a.readSeparately && b.readSeparately) {
+    return false;
+  }
+  if (!a.date.isSameDate(b)) {
+    return true;
+  }
+  return false;
+}
+
 /**
  * @param {any} parsha
  * @param {boolean} il
  * @param {HDate} hd
- * @param {string} variation
+ * @param {any} triennial
  * @return {[boolean, string, string]}
  */
-function doIsraelDiasporaDiffer(parsha, il, hd, variation) {
+function doIsraelDiasporaDiffer(parsha, il, hd, triennial) {
   const parshaName = parsha.name;
   const hyear = hd.getFullYear();
+  if (triennial.readings) {
+    // compare each  3-year index page
+    const otherReadings = make3yearTriennial(hyear, parshaName, !il);
+    for (let yr = 0; yr <= 2; yr++) {
+      if (doTriennialDiffer(otherReadings[yr], triennial.readings[yr])) {
+        return [true, '', ''];
+      }
+    }
+    return [false, '', ''];
+  }
   const otherSedra = HebrewCalendar.getSedra(hyear, !il);
   const otherParsha = otherSedra.lookup(hd);
   const otherParshaName = parshaToString(otherParsha.parsha);
@@ -286,7 +321,7 @@ function doIsraelDiasporaDiffer(parsha, il, hd, variation) {
     }
   }
   const otherTriennial = getRawTriennial(parshaName, hd, !il);
-  if (variation !== otherTriennial.variation) {
+  if (doTriennialDiffer(otherTriennial, triennial)) {
     const anchor = parshaDateAnchor(parshaName, dayjs(hd.greg()), !il);
     return [true, anchor, parshaName];
   }
@@ -355,7 +390,8 @@ function getParshaDateAnchor(ev) {
 
 function makeTriennial(parsha, date, parshaEv, hyear, il) {
   if (!date) {
-    return make3yearTriennial(hyear, parsha.name, il);
+    const readings = make3yearTriennial(hyear, parsha.name, il);
+    return {readings};
   }
   const reading = getTriennialForParshaHaShavua(parshaEv, il);
   if (parsha.name === VEZOT_HABERAKHAH) {
@@ -369,6 +405,9 @@ function makeTriennial(parsha, date, parshaEv, hyear, il) {
     fullParsha: reading.fullParsha,
     hyear: hyear,
     variation: reading.variation,
+    date: reading.date,
+    readSeparately: reading.readSeparately,
+    readTogether: reading.readTogether,
   };
   if (reading.haft) {
     triennial.haftara = reading.haftara;
@@ -382,17 +421,22 @@ function makeTriennial(parsha, date, parshaEv, hyear, il) {
   return triennial;
 }
 
+/**
+ * @param {number} hyear
+ * @param {string} parshaName
+ * @param {boolean} il
+ * @return {any[]}
+ */
 function make3yearTriennial(hyear, parshaName, il) {
-  const triennial = {};
   const startYear = Triennial.getCycleStartYear(hyear);
   const tri = getTriennial(startYear, il);
-  triennial.readings = Array(3);
+  const readings = Array(3);
   for (let yr = 0; yr < 3; yr++) {
     const reading = makeTriReading(tri, yr, parshaName, il);
     reading.hyear = startYear + yr;
-    triennial.readings[yr] = reading;
+    readings[yr] = reading;
   }
-  return triennial;
+  return readings;
 }
 
 function makeTriReading(tri, yr, parshaName, il) {
diff --git a/views/parsha-detail.ejs b/views/parsha-detail.ejs
index 301b671..69b3c21 100644
--- a/views/parsha-detail.ejs
+++ b/views/parsha-detail.ejs
@@ -26,15 +26,15 @@ ol.list-unstyled li {margin-bottom: 0.33em}
 <%- await include('partials/warning-1752.ejs') -%>
 <% } -%>
 <p>Parashat <%=parshaName%> is the <%=parsha.ordinal%> weekly Torah portion in the annual Jewish cycle of Torah reading.
-<% if (date && israelDiasporaDiffer) { -%>
-<p><small>This page displays the <%=il?'Israel':'Diaspora'%> Torah reading for <%=parshaName%> <%=hd.getFullYear()%>.
-The <a href="<%=otherLocationAnchor%>"><%=il?'Diaspora':'Israel'%> schedule</a> is used
-by Jews living <%=il?'outside of':'in'%> modern Israel.</small></p>
-<% } -%>
 <% if (!date) { -%>
 Next read <% if (israelDiasporaDiffer) { %>in <%=locationName%><% } %> on <a href="<%=parshaDateAnchor%>"><time datetime="<%= d.format('YYYY-MM-DD') %>" class="text-nowrap"><%= d.format('D MMMM YYYY') %></time> / <span class="text-nowrap"><%= hd.toString().replace(/'/g, '’') %></span></a>.
 <% } -%>
 </p>
+<% if (israelDiasporaDiffer) { -%>
+<p><small>This page displays the <%=il?'Israel':'Diaspora'%> Torah reading for <%=parshaName%><%= date ? ' ' + hd.getFullYear() : '' %>.
+The <a href="<%=date ? otherLocationAnchor : parshaAnchor + (il?'':'?i=on')%>"><%=il?'Diaspora':'Israel'%> schedule</a> is used
+by Jews living <%=il?'outside of':'in'%> modern Israel.</small></p>
+<% } -%>
 <h4 id="torah"><span class="d-none d-sm-inline">Torah Portion:</span>
 <% if (reading.torahHtml) { %><%- reading.torahHtml -%>
 <% } else { -%>