Implement everything...

lib/mod_list.dart

@@ -194,6 +194,207 @@ class ModList {
     });
     return sortedMods;
   }
+
+  List<List<String>> checkIncompatibilities() {
+    List<List<String>> conflicts = [];
+    List<String> activeModIds = activeMods.keys.toList();
+
+    // Only check each pair once
+    for (int i = 0; i < activeModIds.length; i++) {
+      String modId = activeModIds[i];
+      Mod mod = mods[modId]!;
+
+      for (String incompId in mod.incompatibilities) {
+        // Only process if other mod is active and we haven't checked this pair yet
+        if (activeMods.containsKey(incompId) && modId.compareTo(incompId) < 0) {
+          conflicts.add([modId, incompId]);
+        }
+      }
+    }
+    return conflicts;
+  }
+
+  /// Generate a load order for active mods
+  List<String> generateLoadOrder() {
+    // Check for incompatibilities first
+    List<List<String>> conflicts = checkIncompatibilities();
+    if (conflicts.isNotEmpty) {
+      throw Exception(
+        "Incompatible mods selected: ${conflicts.map((c) => "${c[0]} and ${c[1]}").join(', ')}",
+      );
+    }
+
+    // Reset all marks for topological sort
+    for (Mod mod in mods.values) {
+      mod.visited = false;
+      mod.mark = false;
+      mod.position = -1;
+    }
+
+    List<String> result = [];
+    int position = 0;
+
+    // Topological sort
+    void visit(Mod mod) {
+      if (mod.mark) {
+        List<String> cyclePath =
+            mods.values.where((m) => m.mark).map((m) => m.name).toList();
+        throw Exception(
+          "Cyclic dependency detected: ${cyclePath.join(' -> ')}",
+        );
+      }
+
+      if (!mod.visited) {
+        mod.mark = true;
+
+        // Visit all dependencies
+        for (String depId in mod.dependencies) {
+          if (activeMods.containsKey(depId)) {
+            visit(mods[depId]!);
+          }
+        }
+
+        mod.mark = false;
+        mod.visited = true;
+        mod.position = position++;
+        result.add(mod.id);
+      }
+    }
+
+    // Visit all nodes
+    for (Mod mod in mods.values) {
+      if (!mod.visited) {
+        visit(mod);
+      }
+    }
+
+    // Optimize for soft constraints
+    return _optimizeSoftConstraints(result);
+  }
+
+  /// Calculate how many soft constraints are satisfied
+  Map<String, int> _calculateSoftConstraintsScore(List<String> order) {
+    Map<String, int> positions = {};
+    for (int i = 0; i < order.length; i++) {
+      positions[order[i]] = i;
+    }
+
+    int satisfied = 0;
+    int total = 0;
+
+    for (String modId in order) {
+      Mod mod = mods[modId]!;
+
+      // Check "load before" preferences
+      for (String beforeId in mod.loadBefore) {
+        if (positions.containsKey(beforeId)) {
+          total++;
+          if (positions[modId]! < positions[beforeId]!) {
+            satisfied++;
+          }
+        }
+      }
+
+      // Check "load after" preferences
+      for (String afterId in mod.loadAfter) {
+        if (positions.containsKey(afterId)) {
+          total++;
+          if (positions[modId]! > positions[afterId]!) {
+            satisfied++;
+          }
+        }
+      }
+    }
+
+    return {'satisfied': satisfied, 'total': total};
+  }
+
+  /// Optimize for soft constraints using a greedy approach
+  List<String> _optimizeSoftConstraints(
+    List<String> initialOrder, {
+    int maxIterations = 5,
+  }) {
+    List<String> bestOrder = List.from(initialOrder);
+    Map<String, int> scoreInfo = _calculateSoftConstraintsScore(bestOrder);
+    int bestScore = scoreInfo['satisfied']!;
+    int total = scoreInfo['total']!;
+
+    if (total == 0 || bestScore == total) {
+      return bestOrder; // All constraints satisfied or no constraints
+    }
+
+    // Use a limited number of improvement passes
+    for (int iteration = 0; iteration < maxIterations; iteration++) {
+      bool improved = false;
+
+      // Try moving each mod to improve score
+      for (int i = 0; i < bestOrder.length; i++) {
+        String modId = bestOrder[i];
+        Mod mod = mods[modId]!;
+
+        // Calculate current local score for this mod
+        Map<String, int> currentPositions = {};
+        for (int idx = 0; idx < bestOrder.length; idx++) {
+          currentPositions[bestOrder[idx]] = idx;
+        }
+
+        // Try moving this mod to different positions
+        for (int newPos = 0; newPos < bestOrder.length; newPos++) {
+          if (newPos == i) continue;
+
+          // Skip if move would break hard dependencies
+          bool skip = false;
+          if (newPos < i) {
+            // Moving earlier
+            // Check if any mod between newPos and i depends on this mod
+            for (int j = newPos; j < i; j++) {
+              String depModId = bestOrder[j];
+              if (mods[depModId]!.dependencies.contains(modId)) {
+                skip = true;
+                break;
+              }
+            }
+          } else {
+            // Moving later
+            // Check if this mod depends on any mod between i and newPos
+            for (int j = i + 1; j <= newPos; j++) {
+              String depModId = bestOrder[j];
+              if (mod.dependencies.contains(depModId)) {
+                skip = true;
+                break;
+              }
+            }
+          }
+
+          if (skip) continue;
+
+          // Create a new order with the mod moved
+          List<String> newOrder = List.from(bestOrder);
+          newOrder.removeAt(i);
+          newOrder.insert(newPos, modId);
+
+          // Calculate new score
+          Map<String, int> newScoreInfo = _calculateSoftConstraintsScore(
+            newOrder,
+          );
+          int newScore = newScoreInfo['satisfied']!;
+
+          if (newScore > bestScore) {
+            bestScore = newScore;
+            bestOrder = newOrder;
+            improved = true;
+            break; // Break inner loop, move to next mod
+          }
+        }
+
+        if (improved) break; // If improved, start a new iteration
+      }
+
+      if (!improved) break; // If no improvements in this pass, stop
+    }
+
+    return bestOrder;
+  }
 }
 
 String _expansionNameFromId(String id) {