Add combat action log at /logs

Instruments 9 handlers (combat start/end/pause/resume, next turn,
participant add/remove/toggle, HP changes, conditions) to write
timestamped entries to a Firestore logs collection. New LogsView
at /logs shows entries newest-first with encounter context, and
includes a Clear Log button. Adds a View Logs link in the header.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/App.js

@@ -1,12 +1,12 @@
 import React, { useState, useEffect, useRef, useMemo } from 'react';
 import { initializeApp } from 'firebase/app';
 import { getAuth, signInAnonymously, onAuthStateChanged, signInWithCustomToken } from 'firebase/auth';
-import { getFirestore, doc, setDoc, getDoc, getDocs, collection, onSnapshot, updateDoc, deleteDoc, query, writeBatch } from 'firebase/firestore';
+import { getFirestore, doc, setDoc, getDoc, getDocs, addDoc, collection, onSnapshot, updateDoc, deleteDoc, query, orderBy, limit, writeBatch } from 'firebase/firestore';
 import {
   PlusCircle, Users, Swords, Trash2, Eye, Edit3, Save, XCircle, ChevronsUpDown,
   UserCheck, UserX, HeartCrack, HeartPulse, Zap, EyeOff, ExternalLink, AlertTriangle,
   Play as PlayIcon, Pause as PauseIcon, SkipForward as SkipForwardIcon,
-  StopCircle as StopCircleIcon, Users2, Dices, ChevronUp, ChevronDown 
+  StopCircle as StopCircleIcon, Users2, Dices, ChevronUp, ChevronDown, ScrollText
 } from 'lucide-react';
 
 // Custom CSS for death animation (player view only)
@@ -126,7 +126,8 @@ const getPath = {
   campaign: (id) => `${PUBLIC_DATA_PATH}/campaigns/${id}`,
   encounters: (campaignId) => `${PUBLIC_DATA_PATH}/campaigns/${campaignId}/encounters`,
   encounter: (campaignId, encounterId) => `${PUBLIC_DATA_PATH}/campaigns/${campaignId}/encounters/${encounterId}`,
-  activeDisplay: () => `${PUBLIC_DATA_PATH}/activeDisplay/status`
+  activeDisplay: () => `${PUBLIC_DATA_PATH}/activeDisplay/status`,
+  logs: () => `${PUBLIC_DATA_PATH}/logs`
 };
 
 // ============================================================================
@@ -152,6 +153,17 @@ const sortParticipantsByInitiative = (participants, originalOrder) => {
   });
 };
 
+const LOG_QUERY = [orderBy('timestamp', 'desc'), limit(500)];
+
+const logAction = async (message, context = {}) => {
+  if (!db) return;
+  try {
+    await addDoc(collection(db, getPath.logs()), { timestamp: Date.now(), message, ...context });
+  } catch (err) {
+    console.error('Error writing log:', err);
+  }
+};
+
 // Returns turnOrderIds/currentTurnParticipantId updates when a participant leaves active combat.
 const computeTurnOrderAfterRemoval = (encounter, removedId, updatedParticipants) => {
   if (!encounter.isStarted) return {};
@@ -884,6 +896,7 @@ function ParticipantManager({ encounter, encounterPath, campaignCharacters }) {
       await updateDoc(doc(db, encounterPath), {
         participants: [...participants, newParticipant]
       });
+      logAction(`${nameToAdd} added to encounter (Initiative: ${finalInitiative})`, { encounterName: encounter.name });
 
       setLastRollDetails({
         name: nameToAdd,
@@ -983,6 +996,7 @@ function ParticipantManager({ encounter, encounterPath, campaignCharacters }) {
         participants: updatedParticipants,
         ...computeTurnOrderAfterRemoval(encounter, itemToDelete.id, updatedParticipants)
       });
+      logAction(`${itemToDelete.name} removed from encounter`, { encounterName: encounter.name });
     } catch (err) {
       console.error("Error deleting participant:", err);
       alert("Failed to delete participant. Please try again.");
@@ -1009,6 +1023,7 @@ function ParticipantManager({ encounter, encounterPath, campaignCharacters }) {
 
     try {
       await updateDoc(doc(db, encounterPath), { participants: updatedParticipants, ...turnUpdates });
+      logAction(`${participant.name} ${newIsActive ? 'reactivated' : 'deactivated'}`, { encounterName: encounter.name });
     } catch (err) {
       console.error("Error toggling active state:", err);
     }
@@ -1073,6 +1088,14 @@ function ParticipantManager({ encounter, encounterPath, campaignCharacters }) {
     try {
       await updateDoc(doc(db, encounterPath), { participants: updatedParticipants, ...turnUpdates });
       setHpChangeValues(prev => ({ ...prev, [participantId]: '' }));
+      const hpLine = `${participant.currentHp} → ${newHp} HP`;
+      const deathSuffix = (isDead && !wasDead) ? (participant.type === 'character' ? ' — Unconscious' : ' — Defeated') : '';
+      const resurSuffix = wasResurrected ? ' — Revived' : '';
+      if (changeType === 'damage') {
+        logAction(`${participant.name} took ${amount} damage (${hpLine})${deathSuffix}`, { encounterName: encounter.name });
+      } else {
+        logAction(`${participant.name} healed for ${amount} (${hpLine})${resurSuffix}`, { encounterName: encounter.name });
+      }
     } catch (err) {
       console.error("Error applying HP change:", err);
     }
@@ -1124,16 +1147,22 @@ function ParticipantManager({ encounter, encounterPath, campaignCharacters }) {
 
   const toggleCondition = async (participantId, conditionId) => {
     if (!db) return;
+    const participant = participants.find(p => p.id === participantId);
+    if (!participant) return;
+    const wasActive = (participant.conditions || []).includes(conditionId);
     const updatedParticipants = participants.map(p => {
       if (p.id !== participantId) return p;
       const current = p.conditions || [];
-      const next = current.includes(conditionId)
+      const next = wasActive
         ? current.filter(c => c !== conditionId)
         : [...current, conditionId];
       return { ...p, conditions: next };
     });
     try {
       await updateDoc(doc(db, encounterPath), { participants: updatedParticipants });
+      const cond = CONDITIONS.find(c => c.id === conditionId);
+      const condLabel = cond ? `${cond.label} ${cond.emoji}` : conditionId;
+      logAction(`${participant.name} ${wasActive ? 'lost' : 'gained'} ${condLabel}`, { encounterName: encounter.name });
     } catch (err) {
       console.error("Error updating conditions:", err);
     }
@@ -1586,6 +1615,7 @@ function InitiativeControls({ campaignId, encounter, encounterPath }) {
         activeEncounterId: encounter.id
       }, { merge: true });
 
+      logAction(`Combat started: "${encounter.name}" — ${sortedParticipants[0].name}'s turn (Round 1)`, { encounterName: encounter.name });
       console.log("Encounter started and set as active display.");
     } catch (err) {
       console.error("Error starting encounter:", err);
@@ -1610,6 +1640,7 @@ function InitiativeControls({ campaignId, encounter, encounterPath }) {
         isPaused: newPausedState,
         turnOrderIds: newTurnOrderIds
       });
+      logAction(`Combat ${newPausedState ? 'paused' : 'resumed'}: "${encounter.name}"`, { encounterName: encounter.name });
     } catch (err) {
       console.error("Error toggling pause state:", err);
     }
@@ -1656,6 +1687,7 @@ function InitiativeControls({ campaignId, encounter, encounterPath }) {
         currentTurnParticipantId: activePsInOrder[nextIndex].id,
         round: nextRound
       });
+      logAction(`${activePsInOrder[nextIndex].name}'s turn (Round ${nextRound})`, { encounterName: encounter.name });
     } catch (err) {
       console.error("Error advancing turn:", err);
     }
@@ -1678,6 +1710,7 @@ function InitiativeControls({ campaignId, encounter, encounterPath }) {
         activeEncounterId: null
       }, { merge: true });
 
+      logAction(`Combat ended: "${encounter.name}"`, { encounterName: encounter.name });
       console.log("Encounter ended and deactivated from Player Display.");
     } catch (err) {
       console.error("Error ending encounter:", err);
@@ -2504,6 +2537,88 @@ function DisplayView() {
   );
 }
 
+// ============================================================================
+// LOGS VIEW COMPONENT
+// ============================================================================
+
+function LogsView() {
+  const { data: logs, isLoading } = useFirestoreCollection(getPath.logs(), LOG_QUERY);
+  const [showClearConfirm, setShowClearConfirm] = useState(false);
+
+  const handleClearLogs = async () => {
+    if (!db) return;
+    try {
+      const snapshot = await getDocs(collection(db, getPath.logs()));
+      if (!snapshot.empty) {
+        const batch = writeBatch(db);
+        snapshot.docs.forEach(d => batch.delete(d.ref));
+        await batch.commit();
+      }
+    } catch (err) {
+      console.error('Error clearing logs:', err);
+    }
+    setShowClearConfirm(false);
+  };
+
+  return (
+    <div className="min-h-screen bg-stone-950 text-stone-100 font-garamond">
+      <header className="bg-stone-950 p-4 shadow-lg border-b border-amber-900">
+        <div className="container mx-auto flex justify-between items-center">
+          <h1 className="text-3xl font-bold text-amber-400 font-cinzel tracking-wide">Combat Log</h1>
+          <div className="flex gap-2">
+            <a
+              href="/"
+              className="px-4 py-2 rounded-md text-sm font-medium bg-stone-700 hover:bg-stone-600 text-white transition-colors"
+            >
+              ← Back to Tracker
+            </a>
+            <button
+              onClick={() => setShowClearConfirm(true)}
+              disabled={isLoading || logs.length === 0}
+              className="px-4 py-2 rounded-md text-sm font-medium bg-red-800 hover:bg-red-700 text-white transition-colors disabled:opacity-40 disabled:cursor-not-allowed"
+            >
+              Clear Log
+            </button>
+          </div>
+        </div>
+      </header>
+
+      <main className="container mx-auto p-4 md:p-8">
+        {isLoading ? (
+          <LoadingSpinner message="Loading logs..." />
+        ) : logs.length === 0 ? (
+          <p className="text-stone-400 text-center mt-12 text-lg">No log entries yet.</p>
+        ) : (
+          <>
+            <p className="text-stone-500 text-sm mb-4">{logs.length} entries — newest first</p>
+            <div className="space-y-1 max-w-5xl">
+              {logs.map(entry => (
+                <div key={entry.id} className="flex gap-3 p-3 bg-stone-900 rounded-md border border-stone-800 text-sm">
+                  <span className="text-stone-500 whitespace-nowrap font-mono shrink-0">
+                    {new Date(entry.timestamp).toLocaleString()}
+                  </span>
+                  {entry.encounterName && (
+                    <span className="text-amber-600 whitespace-nowrap shrink-0">[{entry.encounterName}]</span>
+                  )}
+                  <span className="text-stone-100">{entry.message}</span>
+                </div>
+              ))}
+            </div>
+          </>
+        )}
+      </main>
+
+      <ConfirmationModal
+        isOpen={showClearConfirm}
+        onClose={() => setShowClearConfirm(false)}
+        onConfirm={handleClearLogs}
+        title="Clear All Logs?"
+        message="This will permanently delete all log entries and cannot be undone."
+      />
+    </div>
+  );
+}
+
 // ============================================================================
 // MAIN APP COMPONENT
 // ============================================================================
@@ -2514,12 +2629,16 @@ function App() {
   const [isLoading, setIsLoading] = useState(true);
   const [error, setError] = useState(null);
   const [isPlayerViewOnlyMode, setIsPlayerViewOnlyMode] = useState(false);
+  const [isLogsMode, setIsLogsMode] = useState(false);
 
   useEffect(() => {
     const queryParams = new URLSearchParams(window.location.search);
     if (queryParams.get('playerView') === 'true' || window.location.pathname === '/display') {
       setIsPlayerViewOnlyMode(true);
     }
+    if (window.location.pathname === '/logs') {
+      setIsLogsMode(true);
+    }
 
     if (!auth) {
       setError("Firebase Auth not initialized. Check your Firebase configuration.");
@@ -2584,11 +2703,24 @@ function App() {
     );
   }
 
+  if (isLogsMode) {
+    return isAuthReady ? <LogsView /> : <LoadingSpinner message="Authenticating..." />;
+  }
+
   return (
     <div className="min-h-screen bg-stone-950 text-stone-100 font-garamond">
       <header className="bg-stone-950 p-4 shadow-lg border-b border-amber-900">
         <div className="container mx-auto flex justify-between items-center">
           <h1 className="text-3xl font-bold text-amber-400 font-cinzel tracking-wide">TTRPG Initiative Tracker</h1>
+          <div className="flex gap-2">
+            <a
+              href="/logs"
+              target="_blank"
+              rel="noopener noreferrer"
+              className="px-4 py-2 rounded-md text-sm font-medium transition-colors bg-stone-700 hover:bg-stone-600 text-white flex items-center"
+            >
+              <ScrollText size={16} className="mr-2" /> View Logs
+            </a>
             <button
               onClick={openPlayerWindow}
               className="px-4 py-2 rounded-md text-sm font-medium transition-colors bg-amber-700 hover:bg-amber-800 text-white flex items-center"
@@ -2596,6 +2728,7 @@ function App() {
               <ExternalLink size={16} className="mr-2" /> Open Player Window
             </button>
           </div>
+        </div>
       </header>
 
       <main className="container mx-auto p-4 md:p-8">