Make constraints directional and add mismatch detection

drop.sql

@@ -0,0 +1,7 @@
+DROP TABLE IF EXISTS roommate_constraints;
+DROP TABLE IF EXISTS parents;
+DROP TABLE IF EXISTS students;
+DROP TABLE IF EXISTS trip_admins;
+DROP TABLE IF EXISTS trips;
+DROP TYPE IF EXISTS constraint_level;
+DROP TYPE IF EXISTS constraint_kind;

main.go

@@ -654,10 +654,6 @@ func handleCreateConstraint(db *sql.DB) http.HandlerFunc {
 			http.Error(w, "invalid level", http.StatusBadRequest)
 			return
 		}
-		a, b := body.StudentAID, body.StudentBID
-		if a > b {
-			a, b = b, a
-		}
 		var id int64
 		err := db.QueryRow(`
 			INSERT INTO roommate_constraints (student_a_id, student_b_id, kind, level)
@@ -666,7 +662,7 @@ func handleCreateConstraint(db *sql.DB) http.HandlerFunc {
 			JOIN students sb ON sb.id = $2 AND sb.trip_id = $5
 			WHERE sa.id = $1 AND sa.trip_id = $5
 			ON CONFLICT (student_a_id, student_b_id, level) DO UPDATE SET kind = EXCLUDED.kind
-			RETURNING id`, a, b, body.Kind, body.Level, tripID).Scan(&id)
+			RETURNING id`, body.StudentAID, body.StudentBID, body.Kind, body.Level, tripID).Scan(&id)
 		if err != nil {
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return

schema.sql

@@ -43,6 +43,6 @@ CREATE TABLE IF NOT EXISTS roommate_constraints (
     student_b_id BIGINT NOT NULL REFERENCES students(id) ON DELETE CASCADE,
     kind constraint_kind NOT NULL,
     level constraint_level NOT NULL,
-    CHECK(student_a_id < student_b_id),
+    CHECK(student_a_id != student_b_id),
     UNIQUE(student_a_id, student_b_id, level)
 );

static/trip.html

@@ -62,6 +62,7 @@
         .constraint-add { display: flex; gap: 0.5rem; align-items: center; margin-top: 0.3rem; }
         .constraint-add select { font-size: 0.75rem; padding: 0.15rem; border: 1px solid var(--wa-color-neutral-300, #ccc); border-radius: 0.25rem; }
         #conflicts { margin-bottom: 0.5rem; }
+        #mismatches { margin-bottom: 0.5rem; }
         .conflict-row { margin-bottom: 0.2rem; }
         .conflict-icon { background: var(--wa-color-danger-50, #dc3545); color: white; border-radius: 0.15rem; padding: 0 0.15rem; font-size: 0.6rem; line-height: 1.2; vertical-align: middle; margin-right: 0.1rem; display: inline-block; }
     </style>
@@ -81,6 +82,7 @@
             <input id="room-size" type="number" min="1">
         </div>
         <div id="conflicts"></div>
+        <div id="mismatches"></div>
         <div id="students"></div>
         <wa-details summary="Add Student">
             <div class="add-form">

static/trip.js

@@ -57,6 +57,45 @@ async function loadStudents() {
         }
     }
 
+    const kindSpan = (kind) => {
+        const span = document.createElement('span');
+        span.textContent = kindLabels[kind];
+        span.style.color = kindColor[kind];
+        span.style.fontWeight = 'bold';
+        return span;
+    };
+
+    const allOveralls = {};
+    for (const s of students) {
+        const myC = constraints.filter(c => c.student_a_id === s.id);
+        const byPeer = {};
+        for (const c of myC) {
+            if (!byPeer[c.student_b_id]) byPeer[c.student_b_id] = {};
+            byPeer[c.student_b_id][c.level] = c;
+        }
+        allOveralls[s.id] = {};
+        for (const [peerId, levels] of Object.entries(byPeer)) {
+            const eff = levels.admin || levels.parent || levels.student;
+            if (eff) allOveralls[s.id][peerId] = eff;
+        }
+    }
+
+    const mismatchList = [];
+    for (const s of students) {
+        for (const [bId, effA] of Object.entries(allOveralls[s.id])) {
+            if (!allOveralls[bId] || !allOveralls[bId][s.id]) continue;
+            const effB = allOveralls[bId][s.id];
+            if (isPositive(effA.kind) && !isPositive(effB.kind)) {
+                mismatchList.push({
+                    nameA: s.name,
+                    nameB: students.find(x => x.id === parseInt(bId)).name,
+                    kindA: effA.kind,
+                    kindB: effB.kind,
+                });
+            }
+        }
+    }
+
     const conflictsEl = document.getElementById('conflicts');
     const conflictsWasOpen = conflictsEl.querySelector('wa-details')?.open;
     conflictsEl.innerHTML = '';
@@ -64,13 +103,6 @@ async function loadStudents() {
         const det = document.createElement('wa-details');
         det.summary = '\u26a0 Overrides (' + conflictList.length + ')';
         if (conflictsWasOpen) det.open = true;
-        const kindSpan = (kind) => {
-            const span = document.createElement('span');
-            span.textContent = kindLabels[kind];
-            span.style.color = kindColor[kind];
-            span.style.fontWeight = 'bold';
-            return span;
-        };
         for (const conflict of conflictList) {
             const div = document.createElement('div');
             div.className = 'conflict-row';
@@ -91,6 +123,25 @@ async function loadStudents() {
         conflictsEl.appendChild(det);
     }
 
+    const mismatchesEl = document.getElementById('mismatches');
+    const mismatchesWasOpen = mismatchesEl.querySelector('wa-details')?.open;
+    mismatchesEl.innerHTML = '';
+    if (mismatchList.length > 0) {
+        const det = document.createElement('wa-details');
+        det.summary = '\u26a0 Mismatches (' + mismatchList.length + ')';
+        if (mismatchesWasOpen) det.open = true;
+        for (const m of mismatchList) {
+            const div = document.createElement('div');
+            div.className = 'conflict-row';
+            div.appendChild(document.createTextNode(m.nameA + ' \u2192 ' + m.nameB + ': '));
+            div.appendChild(kindSpan(m.kindA));
+            div.appendChild(document.createTextNode(' but ' + m.nameB + ' \u2192 ' + m.nameA + ': '));
+            div.appendChild(kindSpan(m.kindB));
+            det.appendChild(div);
+        }
+        mismatchesEl.appendChild(det);
+    }
+
     const container = document.getElementById('students');
     const openStates = {};
     for (const card of container.children) {
@@ -167,26 +218,14 @@ async function loadStudents() {
         const cDetails = document.createElement('wa-details');
         cDetails.summary = 'Constraints';
 
-        const myConstraints = constraints.filter(c => c.student_a_id === student.id || c.student_b_id === student.id);
+        const myConstraints = constraints.filter(c => c.student_a_id === student.id);
 
-        const byPeer = {};
+        const overall = Object.values(allOveralls[student.id] || {});
-        for (const c of myConstraints) {
-            const otherId = c.student_a_id === student.id ? c.student_b_id : c.student_a_id;
-            if (!byPeer[otherId]) byPeer[otherId] = {};
-            byPeer[otherId][c.level] = c;
-        }
-        const overall = [];
-        for (const levels of Object.values(byPeer)) {
-            const eff = levels.admin || levels.parent || levels.student;
-            if (eff) overall.push(eff);
-        }
         if (overall.length > 0) {
             overall.sort((a, b) => {
                 const kd = kindOrder[a.kind] - kindOrder[b.kind];
                 if (kd !== 0) return kd;
-                const na = a.student_a_id === student.id ? a.student_b_name : a.student_a_name;
+                return a.student_b_name.localeCompare(b.student_b_name);
-                const nb = b.student_a_id === student.id ? b.student_b_name : b.student_a_name;
-                return na.localeCompare(nb);
             });
             const group = document.createElement('div');
             group.className = 'constraint-group';
@@ -195,11 +234,10 @@ async function loadStudents() {
             levelLabel.textContent = 'Overall';
             group.appendChild(levelLabel);
             for (const c of overall) {
-                const otherName = c.student_a_id === student.id ? c.student_b_name : c.student_a_name;
                 const tag = document.createElement('wa-tag');
                 tag.size = 'small';
                 tag.variant = kindVariant[c.kind];
-                tag.textContent = kindLabels[c.kind] + ': ' + otherName;
+                tag.textContent = kindLabels[c.kind] + ': ' + c.student_b_name;
                 tag.title = 'From ' + capitalize(c.level);
                 group.appendChild(tag);
             }
@@ -212,9 +250,7 @@ async function loadStudents() {
             lc.sort((a, b) => {
                 const kd = kindOrder[a.kind] - kindOrder[b.kind];
                 if (kd !== 0) return kd;
-                const na = a.student_a_id === student.id ? a.student_b_name : a.student_a_name;
+                return a.student_b_name.localeCompare(b.student_b_name);
-                const nb = b.student_a_id === student.id ? b.student_b_name : b.student_a_name;
-                return na.localeCompare(nb);
             });
             const group = document.createElement('div');
             group.className = 'constraint-group';
@@ -223,7 +259,7 @@ async function loadStudents() {
             levelLabel.textContent = level.charAt(0).toUpperCase() + level.slice(1);
             group.appendChild(levelLabel);
             for (const c of lc) {
-                const otherName = c.student_a_id === student.id ? c.student_b_name : c.student_a_name;
+                const otherName = c.student_b_name;
                 const tag = document.createElement('wa-tag');
                 tag.size = 'small';
                 tag.variant = kindVariant[c.kind];