feat(M4-009,M4-010,M4-011): routing rules CRUD, per-user overrides, agent capabilities (#320)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

apps/gateway/src/agent/routing/routing.controller.ts

@@ -0,0 +1,234 @@
+import {
+  Body,
+  Controller,
+  Delete,
+  ForbiddenException,
+  Get,
+  HttpCode,
+  HttpStatus,
+  Inject,
+  NotFoundException,
+  Param,
+  Patch,
+  Post,
+  UseGuards,
+} from '@nestjs/common';
+import { routingRules, type Db, and, asc, eq, or, inArray } from '@mosaic/db';
+import { DB } from '../../database/database.module.js';
+import { AuthGuard } from '../../auth/auth.guard.js';
+import { CurrentUser } from '../../auth/current-user.decorator.js';
+import {
+  CreateRoutingRuleDto,
+  UpdateRoutingRuleDto,
+  ReorderRoutingRulesDto,
+} from './routing.dto.js';
+
+@Controller('api/routing/rules')
+@UseGuards(AuthGuard)
+export class RoutingController {
+  constructor(@Inject(DB) private readonly db: Db) {}
+
+  /**
+   * GET /api/routing/rules
+   * List all rules visible to the authenticated user:
+   * - All system rules
+   * - User's own rules
+   * Ordered by priority ascending (lower number = higher priority).
+   */
+  @Get()
+  async list(@CurrentUser() user: { id: string }) {
+    const rows = await this.db
+      .select()
+      .from(routingRules)
+      .where(
+        or(
+          eq(routingRules.scope, 'system'),
+          and(eq(routingRules.scope, 'user'), eq(routingRules.userId, user.id)),
+        ),
+      )
+      .orderBy(asc(routingRules.priority));
+
+    return rows;
+  }
+
+  /**
+   * GET /api/routing/rules/effective
+   * Return the merged rule set in priority order.
+   * User-scoped rules are checked before system rules at the same priority
+   * (achieved by ordering: priority ASC, then scope='user' first).
+   */
+  @Get('effective')
+  async effective(@CurrentUser() user: { id: string }) {
+    const rows = await this.db
+      .select()
+      .from(routingRules)
+      .where(
+        and(
+          eq(routingRules.enabled, true),
+          or(
+            eq(routingRules.scope, 'system'),
+            and(eq(routingRules.scope, 'user'), eq(routingRules.userId, user.id)),
+          ),
+        ),
+      )
+      .orderBy(asc(routingRules.priority));
+
+    // For rules with the same priority: user rules beat system rules.
+    // Group by priority then stable-sort each group: user before system.
+    const grouped = new Map<number, typeof rows>();
+    for (const row of rows) {
+      const bucket = grouped.get(row.priority) ?? [];
+      bucket.push(row);
+      grouped.set(row.priority, bucket);
+    }
+
+    const effective: typeof rows = [];
+    for (const [, bucket] of [...grouped.entries()].sort(([a], [b]) => a - b)) {
+      // user-scoped rules first within the same priority bucket
+      const userRules = bucket.filter((r) => r.scope === 'user');
+      const systemRules = bucket.filter((r) => r.scope === 'system');
+      effective.push(...userRules, ...systemRules);
+    }
+
+    return effective;
+  }
+
+  /**
+   * POST /api/routing/rules
+   * Create a new routing rule. Scope is forced to 'user' (users cannot create
+   * system rules). The authenticated user's ID is attached automatically.
+   */
+  @Post()
+  async create(@Body() dto: CreateRoutingRuleDto, @CurrentUser() user: { id: string }) {
+    const [created] = await this.db
+      .insert(routingRules)
+      .values({
+        name: dto.name,
+        priority: dto.priority,
+        scope: 'user',
+        userId: user.id,
+        conditions: dto.conditions as unknown as Record<string, unknown>[],
+        action: dto.action as unknown as Record<string, unknown>,
+        enabled: dto.enabled ?? true,
+      })
+      .returning();
+
+    return created;
+  }
+
+  /**
+   * PATCH /api/routing/rules/reorder
+   * Reassign priorities so that the order of `ruleIds` reflects ascending
+   * priority (index 0 = priority 0, index 1 = priority 1, …).
+   * Only the authenticated user's own rules can be reordered.
+   */
+  @Patch('reorder')
+  async reorder(@Body() dto: ReorderRoutingRulesDto, @CurrentUser() user: { id: string }) {
+    // Verify all supplied IDs belong to this user
+    const owned = await this.db
+      .select({ id: routingRules.id })
+      .from(routingRules)
+      .where(
+        and(
+          inArray(routingRules.id, dto.ruleIds),
+          eq(routingRules.scope, 'user'),
+          eq(routingRules.userId, user.id),
+        ),
+      );
+
+    const ownedIds = new Set(owned.map((r) => r.id));
+    const unowned = dto.ruleIds.filter((id) => !ownedIds.has(id));
+    if (unowned.length > 0) {
+      throw new ForbiddenException(
+        `Cannot reorder rules that do not belong to you: ${unowned.join(', ')}`,
+      );
+    }
+
+    // Apply new priorities in transaction
+    const updates = await this.db.transaction(async (tx) => {
+      const results = [];
+      for (let i = 0; i < dto.ruleIds.length; i++) {
+        const [updated] = await tx
+          .update(routingRules)
+          .set({ priority: i, updatedAt: new Date() })
+          .where(and(eq(routingRules.id, dto.ruleIds[i]!), eq(routingRules.userId, user.id)))
+          .returning();
+        if (updated) results.push(updated);
+      }
+      return results;
+    });
+
+    return updates;
+  }
+
+  /**
+   * PATCH /api/routing/rules/:id
+   * Update a user-owned rule. System rules cannot be modified by regular users.
+   */
+  @Patch(':id')
+  async update(
+    @Param('id') id: string,
+    @Body() dto: UpdateRoutingRuleDto,
+    @CurrentUser() user: { id: string },
+  ) {
+    const [existing] = await this.db.select().from(routingRules).where(eq(routingRules.id, id));
+
+    if (!existing) throw new NotFoundException('Routing rule not found');
+
+    if (existing.scope === 'system') {
+      throw new ForbiddenException('System routing rules cannot be modified');
+    }
+
+    if (existing.userId !== user.id) {
+      throw new ForbiddenException('Routing rule does not belong to the current user');
+    }
+
+    const updatePayload: Partial<typeof routingRules.$inferInsert> = {
+      updatedAt: new Date(),
+    };
+
+    if (dto.name !== undefined) updatePayload.name = dto.name;
+    if (dto.priority !== undefined) updatePayload.priority = dto.priority;
+    if (dto.conditions !== undefined)
+      updatePayload.conditions = dto.conditions as unknown as Record<string, unknown>[];
+    if (dto.action !== undefined)
+      updatePayload.action = dto.action as unknown as Record<string, unknown>;
+    if (dto.enabled !== undefined) updatePayload.enabled = dto.enabled;
+
+    const [updated] = await this.db
+      .update(routingRules)
+      .set(updatePayload)
+      .where(and(eq(routingRules.id, id), eq(routingRules.userId, user.id)))
+      .returning();
+
+    if (!updated) throw new NotFoundException('Routing rule not found');
+    return updated;
+  }
+
+  /**
+   * DELETE /api/routing/rules/:id
+   * Delete a user-owned routing rule. System rules cannot be deleted.
+   */
+  @Delete(':id')
+  @HttpCode(HttpStatus.NO_CONTENT)
+  async remove(@Param('id') id: string, @CurrentUser() user: { id: string }) {
+    const [existing] = await this.db.select().from(routingRules).where(eq(routingRules.id, id));
+
+    if (!existing) throw new NotFoundException('Routing rule not found');
+
+    if (existing.scope === 'system') {
+      throw new ForbiddenException('System routing rules cannot be deleted');
+    }
+
+    if (existing.userId !== user.id) {
+      throw new ForbiddenException('Routing rule does not belong to the current user');
+    }
+
+    const [deleted] = await this.db
+      .delete(routingRules)
+      .where(and(eq(routingRules.id, id), eq(routingRules.userId, user.id)))
+      .returning();
+
+    if (!deleted) throw new NotFoundException('Routing rule not found');
+  }
+}