CUB-134: Build printers list page

Reviewed-on: #42

docs/CONTEXT.md

@@ -0,0 +1,214 @@
+# Extrudex — Project Context
+
+> **Last updated:** 2026-05-21
+> **Repo:** `CubeCraft-Creations/Extrudex` | **Host:** `code.cubecraftcreations.com`
+> **Local clone:** `/mnt/ai-storage/projects/Extrudex` | **Default branch:** `dev`
+> **Discord:** `DISCORD_DEV_EXTRUDEX_CHANNEL_ID`
+> **Linear Epic:** [CUB-110](https://linear.app/cubecraft-creations/issue/CUB-110)
+
+---
+
+## Overview
+
+Custom filament inventory and print tracking system for CubeCraft Creations. Tracks spool consumption, material costs, and per-print COGS across a fleet of 6 FDM printers (5 Bambu Lab + 1 Elegoo Centauri Carbon) + resin printers. Kiosk interface on Raspberry Pi 5 with USB barcode scanner.
+
+**Active refactor in progress:** .NET → Go + React (CUB-110 epic).
+
+## Tech Stack
+
+| Layer | Technology | Notes |
+|-------|-----------|-------|
+| Backend (legacy) | ASP.NET Core 9 + EF Core | Being replaced by Go |
+| Backend (new) | Go 1.24+ | Chi router, pgx (PostgreSQL), gorilla/websocket, paho.mqtt.golang |
+| Frontend (legacy) | Angular 17+ | Being replaced by React |
+| Frontend (new) | React 18 + TypeScript + Tailwind CSS | Vite |
+| Database | PostgreSQL 16+ | snake_case naming |
+| Real-time | SSE (Server-Sent Events) | Replaces SignalR |
+| Printer integrations | Moonraker REST + WebSocket, MQTT TLS | Elegoo/Klipper + Bambu Lab |
+| CI/CD | Gitea Actions | `.gitea/workflows/dev.yml` |
+| Deployment | Docker/Compose, Pi 5 kiosk | |
+
+## Key Design Decisions
+
+1. **Custom system over Spoolman** — Full control over data model and integrations
+2. **MaterialFinish required** on every spool; default is "Basic"
+3. **MaterialModifier is optional**
+4. **Grams derived from:** `mm_extruded × filament_cross_section_area × material_density`
+5. **Push over poll** — SSE + MQTT preferred; Moonraker polling is fallback
+6. **Snake_case** for all PostgreSQL identifiers
+
+## Project Structure
+
+```
+Extrudex/
+├── backend/                         # Original .NET backend (being replaced)
+│   ├── API/Controllers/             # Filaments, Spools, PrintJobs, Printers, Materials, QR, UsageLogs, Cost
+│   ├── API/DTOs/                    # DTOs per domain
+│   ├── API/Validators/              # FluentValidation rules
+│   ├── API/Hubs/                    # SignalR PrinterHub
+│   ├── API/Jobs/                    # Background sync jobs
+│   ├── Domain/Entities/             # EF Core entities (Printer, Spool, PrintJob, MaterialBase, etc.)
+│   ├── Domain/Enums/                # ConnectionType, DataSource, JobStatus, PrinterStatus, QrResourceType
+│   ├── Domain/Interfaces/           # Service interfaces
+│   ├── Infrastructure/Data/         # EF DbContext, Configurations, Migrations, SeedData
+│   ├── Infrastructure/Services/     # MoonrakerClient, CostPerPrint, UsageLog, FilamentUsage, QR
+│   └── Program.cs                  # ASP.NET entry point
+├── cmd/server/main.go              # Go entrypoint (new), worker discovery, graceful shutdown
+├── internal/                       # Go backend (new)
+│   ├── config/config.go            # Env vars
+│   ├── db/db.go                    # PostgreSQL connection pool (pgx)
+│   ├── models/models.go            # Go domain structs
+│   ├── router/router.go            # Chi HTTP routes
+│   ├── sse/broadcaster.go          # SSE broadcaster
+│   ├── sse/events.go               # SSE event types
+│   ├── sse/handler.go              # SSE HTTP handler
+│   ├── handlers/                   # API handlers (filament, health, material, print_job, printer, usage_log)
+│   ├── repositories/               # DB access layer
+│   └── services/                   # Business logic + validation
+├── migrations/                     # Go-migrate SQL migrations
+│   ├── 000001_initial_schema.up.sql
+│   ├── 000001_initial_schema.down.sql
+│   ├── 000002_seed_data.up.sql
+│   └── 000002_seed_data.down.sql
+├── frontend/                       # React frontend (new)
+│   ├── src/
+│   │   ├── App.tsx
+│   │   ├── main.tsx
+│   │   ├── components/             # ColorSwatch, LoadingSpinner, RecentPrints, SummaryCard
+│   │   ├── pages/
+│   │   │   ├── Dashboard.tsx       # Main dashboard with summary cards + recent prints
+│   │   │   └── InventoryPage.tsx   # Filament inventory list (table + filters)
+│   │   ├── services/
+│   │   │   ├── api.ts              # Axios client
+│   │   │   └── filamentService.ts
+│   │   ├── stores/                 # State stores (WIP)
+│   │   ├── types/
+│   │   │   ├── filament.ts
+│   │   │   └── index.ts
+│   │   └── hooks/
+│   ├── Dockerfile + nginx.conf
+│   └── vite.config.ts, tailwind.config.js
+├── design/                         # UX/design specs + mockup images
+│   ├── homepage-spec.md
+│   ├── 01-filament-inventory-list.md
+│   ├── 02-spool-detail-view.md
+│   ├── 03-smart-intake-workflow.md
+│   ├── smart-intake-identify-spec.md
+│   └── *.jpg / *.png               # Mockup images (kiosk + mobile)
+├── docker-compose.dev.yml
+└── deploy.sh
+```
+
+## Database Schema (PostgreSQL — .NET EF Core Migrations)
+
+Core entities managed by EF Core with full configurations:
+- **Printers** — id, name, type (BambuLab/Moonraker), connection_type, status, ip_address, mac_address, ams_count
+- **AmsUnit / AmsSlot** — Bambu Lab AMS tray tracking
+- **Spools** — filament inventory with material, color, weight, location, QR support
+- **MaterialBase / MaterialFinish / MaterialModifier** — material taxonomy
+- **PrintJobs** — job tracking with status, cost, filament consumption
+- **UsageLogs** — per-printer filament consumption records
+- **FilamentUsage** — aggregated per-spool consumption tracking
+- **FilamentUsageSyncJob** — background Moonraker polling
+- **MoonrakerPrinterSyncJob** — background printer status sync
+
+## API Endpoints (.NET)
+
+| Method | Endpoint | Description |
+|--------|----------|-------------|
+| GET | /api/filaments | List filaments (paginated, filterable) |
+| POST | /api/filaments | Create filament |
+| GET | /api/filaments/{id} | Get filament detail |
+| PUT | /api/filaments/{id} | Update filament |
+| DELETE | /api/filaments/{id} | Delete filament |
+| GET | /api/spools | List spools |
+| POST | /api/spools | Create spool |
+| GET | /api/spools/{id} | Get spool detail |
+| PUT | /api/spools/{id} | Update spool |
+| DELETE | /api/spools/{id} | Delete spool |
+| GET | /api/print-jobs | List print jobs |
+| POST | /api/print-jobs | Create print job |
+| GET | /api/print-jobs/{id} | Get print job detail |
+| GET | /api/printers | List printers |
+| POST | /api/printers | Register printer |
+| GET | /api/printers/{id} | Get printer detail |
+| GET | /api/printers/{id}/costs | Per-print cost summary |
+| GET | /api/printers/{id}/usage | Filament usage history |
+| GET | /api/materials/bases | List material bases |
+| POST | /api/materials/bases | Create material base |
+| GET | /api/materials/finishes | List material finishes |
+| POST | /api/materials/finishes | Create material finish |
+| GET | /api/materials/modifiers | List material modifiers |
+| POST | /api/materials/modifiers | Create modifier |
+| GET | /api/materials/lookups | Unified material lookup |
+| GET | /api/qr/resolve/{code} | QR code resolve |
+| GET | /api/usage-logs | List usage logs |
+| POST | /api/usage-logs | Create usage log |
+
+## CUB-110 Epic Progress (Go + React Rewrite)
+
+| Sub-task | Title | Status | Agent |
+|----------|-------|--------|-------|
+| CUB-111 | Design PostgreSQL schema | Done | Hex |
+| CUB-112 | Scaffold Go backend | Done | Dex |
+| CUB-113 | Core CRUD API endpoints | Done | Dex |
+| CUB-116 | Scaffold React frontend | In Review | Rex |
+| CUB-117 | Moonraker + MQTT integrations | In Progress | Dex |
+| CUB-118 | (deprecated → CUB-135 + CUB-136) | — | — |
+| CUB-130 | Add/Edit Filament form | In Review | Rex |
+| CUB-131 | Filament Detail page | In Review | Rex |
+| CUB-132 | Filament Inventory list | Done | Rex |
+| CUB-133 | Dashboard summary cards | In Review | Rex |
+| CUB-134 | Printers list page | Todo | Rex |
+| CUB-135 | Subscribe to SSE in React | In Review | Rex |
+| CUB-136 | Add SSE endpoint in Go | In Review | Dex |
+| CUB-128 | Settings page | Todo | — |
+| CUB-129 | Print Jobs list page | Todo | — |
+| CUB-114 | Pi 5 kiosk deployment | Todo | — |
+
+## Active Branches
+
+| Branch | Agent | Issue | Status |
+|--------|-------|-------|--------|
+| `agent/dex/CUB-117-moonraker-mqtt-go` | Dex | CUB-117 | Local commit ready |
+| `agent/dex/CUB-136-sse-endpoint` | Dex | CUB-136 | PR open |
+| `agent/rex/CUB-130-filament-form` | Rex | CUB-130 | PR open |
+| `agent/rex/CUB-131-filament-detail` | Rex | CUB-131 | PR open |
+| `agent/rex/CUB-133-dashboard-cards` | Rex | CUB-133 | PR open |
+| `agent/rex/CUB-135-sse-subscribe` | Rex | CUB-135 | PR open |
+
+## Known Limitations
+
+- Go rewrite is in progress — backend `internal/` is new Go code, but legacy .NET code still serves endpoints
+- Kiosk deployment not finalized (CUB-114)
+- Smart intake workflow is designed but not implemented
+- MQTT Bambu Lab integration is partially complete (CUB-117)
+
+## Default Agent Assignments
+
+| Area | Agent | Notes |
+|------|-------|-------|
+| Backend (Go API, Moonraker, MQTT) | Dex | gitea-dex MCP |
+| Database (PostgreSQL schema, migrations) | Hex | gitea-hex MCP |
+| Frontend (React, Tailwind) | Rex | gitea-rex MCP |
+| Design (wireframes, UX) | Sketch | |
+
+## Getting Started
+
+```bash
+cd /mnt/ai-storage/projects/Extrudex
+git checkout dev
+git pull origin dev
+
+# Legacy .NET backend
+cd backend && dotnet run
+
+# New Go backend
+go run cmd/server/main.go
+
+# React frontend
+cd frontend && npm install && npm run dev
+
+# Docker
+docker compose -f docker-compose.dev.yml up --build
+```

frontend/src/App.tsx

@@ -1,14 +1,36 @@
-import { Routes, Route } from 'react-router-dom'
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
+import { BrowserRouter, Routes, Route } from 'react-router-dom'
 import Dashboard from './pages/Dashboard'
+import InventoryPage from './pages/InventoryPage'
+import PrintersPage from './pages/PrintersPage'
 
-function App() {
+const queryClient = new QueryClient()
+
+export default function App() {
   return (
-    <div className="min-h-screen bg-slate-900">
+    <QueryClientProvider client={queryClient}>
+      <BrowserRouter>
+        <div className="min-h-screen bg-slate-900 text-slate-50">
+          <header className="bg-slate-800 border-b border-slate-700 px-4 py-3 flex items-center gap-4 sticky top-0 z-20">
+            <a href="/" className="flex items-center gap-3 no-underline">
+              <div className="w-8 h-8 rounded bg-emerald-500 flex items-center justify-center text-slate-900 font-bold text-lg">E</div>
+              <h1 className="text-lg font-semibold text-slate-50">Extrudex</h1>
+            </a>
+            <nav className="flex items-center gap-1 ml-2">
+              <a href="/" className="px-3 py-1.5 rounded-md text-sm text-slate-300 hover:text-slate-100 hover:bg-slate-700 transition-colors">Dashboard</a>
+              <a href="/inventory" className="px-3 py-1.5 rounded-md text-sm text-slate-300 hover:text-slate-100 hover:bg-slate-700 transition-colors">Inventory</a>
+              <a href="/printers" className="px-3 py-1.5 rounded-md text-sm text-slate-300 hover:text-slate-100 hover:bg-slate-700 transition-colors">Printers</a>
+            </nav>
+          </header>
+          <main className="p-4">
             <Routes>
               <Route path="/" element={<Dashboard />} />
+              <Route path="/inventory" element={<InventoryPage />} />
+              <Route path="/printers" element={<PrintersPage />} />
             </Routes>
+          </main>
         </div>
+      </BrowserRouter>
+    </QueryClientProvider>
   )
 }
-
-export default App

frontend/src/components/ColorSwatch.tsx

@@ -0,0 +1,18 @@
+interface ColorSwatchProps {
+  colorHex: string
+  size?: number
+}
+
+export default function ColorSwatch({ colorHex, size = 24 }: ColorSwatchProps) {
+  return (
+    <div
+      className="rounded-full border border-slate-600 shadow-sm inline-block"
+      style={{
+        backgroundColor: colorHex.startsWith('#') ? colorHex : `#${colorHex}`,
+        width: size,
+        height: size,
+      }}
+      title={colorHex}
+    />
+  )
+}

frontend/src/pages/InventoryPage.tsx

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+import { useState, useMemo } from 'react'
+import { useQuery } from '@tanstack/react-query'
+import { Search, Filter, ChevronLeft, ChevronRight, Trash2, Pencil, Plus, AlertTriangle } from 'lucide-react'
+import ColorSwatch from '../components/ColorSwatch'
+import { fetchFilaments, deleteFilament } from '../services/filamentService'
+import type { FilamentSpool, FilamentFilter } from '../types/filament'
+
+const PAGE_SIZE = 20
+
+type SortField = 'name' | 'remaining_grams' | 'cost_usd'
+type SortDir = 'asc' | 'desc'
+
+export default function InventoryPage() {
+  const [search, setSearch] = useState('')
+  const [material, setMaterial] = useState('')
+  const [finish, setFinish] = useState('')
+  const [lowStockOnly, setLowStockOnly] = useState(false)
+  const [sortBy, setSortBy] = useState<SortField>('name')
+  const [sortDir, setSortDir] = useState<SortDir>('asc')
+  const [page, setPage] = useState(0)
+  const [deleteId, setDeleteId] = useState<number | null>(null)
+
+  const filter: FilamentFilter = useMemo(() => ({
+    material: material || undefined,
+    finish: finish || undefined,
+    low_stock: lowStockOnly,
+    sort_by: sortBy,
+    sort_dir: sortDir,
+    limit: PAGE_SIZE,
+    offset: page * PAGE_SIZE,
+  }), [material, finish, lowStockOnly, sortBy, sortDir, page])
+
+  const { data, isLoading, error, refetch } = useQuery({
+    queryKey: ['filaments', filter],
+    queryFn: () => fetchFilaments(filter),
+  })
+
+  const filaments = data?.data ?? []
+  const total = data?.total ?? 0
+  const totalPages = Math.max(1, Math.ceil(total / PAGE_SIZE))
+
+  // Client-side search filter (name/barcode) since backend may not support it yet.
+  const filtered = useMemo(() => {
+    if (!search.trim()) return filaments
+    const q = search.toLowerCase()
+    return filaments.filter(
+      (f: FilamentSpool) =>
+        f.name.toLowerCase().includes(q) ||
+        (f.barcode && f.barcode.toLowerCase().includes(q))
+    )
+  }, [filaments, search])
+
+  const handleSort = (field: SortField) => {
+    if (sortBy === field) {
+      setSortDir(prev => (prev === 'asc' ? 'desc' : 'asc'))
+    } else {
+      setSortBy(field)
+      setSortDir('asc')
+    }
+    setPage(0)
+  }
+
+  const handleDelete = async (id: number) => {
+    await deleteFilament(id)
+    setDeleteId(null)
+    refetch()
+  }
+
+  const SortIndicator = ({ field }: { field: SortField }) => {
+    if (sortBy !== field) return <span className="text-slate-600 ml-1">↕</span>
+    return <span className="text-emerald-400 ml-1">{sortDir === 'asc' ? '↑' : '↓'}</span>
+  }
+
+  return (
+    <div className="space-y-4">
+      {/* Header */}
+      <div className="flex flex-col sm:flex-row sm:items-center sm:justify-between gap-3">
+        <div>
+          <h2 className="text-xl font-bold text-slate-100">Filament Inventory</h2>
+          <p className="text-sm text-slate-400">{total} spool(s) total</p>
+        </div>
+        <button className="inline-flex items-center gap-2 rounded-lg bg-emerald-600 px-4 py-2 text-sm font-semibold text-white hover:bg-emerald-500 active:bg-emerald-700 transition-colors">
+          <Plus size={16} /> Add Spool
+        </button>
+      </div>
+
+      {/* Filters */}
+      <div className="flex flex-col lg:flex-row gap-3">
+        {/* Search */}
+        <div className="relative flex-1">
+          <Search size={16} className="absolute left-3 top-1/2 -translate-y-1/2 text-slate-400" />
+          <input
+            type="text"
+            placeholder="Search by name or barcode…"
+            value={search}
+            onChange={e => { setSearch(e.target.value); setPage(0) }}
+            className="w-full rounded-lg bg-slate-800 border border-slate-700 pl-9 pr-3 py-2 text-sm text-slate-100 placeholder-slate-500 focus:outline-none focus:ring-2 focus:ring-emerald-500 focus:border-emerald-500"
+          />
+        </div>
+
+        {/* Material filter */}
+        <select
+          value={material}
+          onChange={e => { setMaterial(e.target.value); setPage(0) }}
+          className="rounded-lg bg-slate-800 border border-slate-700 px-3 py-2 text-sm text-slate-100 focus:outline-none focus:ring-2 focus:ring-emerald-500"
+        >
+          <option value="">All Materials</option>
+          <option value="PLA">PLA</option>
+          <option value="PETG">PETG</option>
+          <option value="ABS">ABS</option>
+          <option value="TPU">TPU</option>
+          <option value="ASA">ASA</option>
+          <option value="Nylon">Nylon</option>
+          <option value="PC">PC</option>
+        </select>
+
+        {/* Finish filter */}
+        <select
+          value={finish}
+          onChange={e => { setFinish(e.target.value); setPage(0) }}
+          className="rounded-lg bg-slate-800 border border-slate-700 px-3 py-2 text-sm text-slate-100 focus:outline-none focus:ring-2 focus:ring-emerald-500"
+        >
+          <option value="">All Finishes</option>
+          <option value="Basic">Basic</option>
+          <option value="Silk">Silk</option>
+          <option value="Matte">Matte</option>
+          <option value="Glossy">Glossy</option>
+          <option value="Wood">Wood</option>
+          <option value="Marble">Marble</option>
+        </select>
+
+        {/* Low stock toggle */}
+        <label className="inline-flex items-center gap-2 rounded-lg bg-slate-800 border border-slate-700 px-3 py-2 text-sm text-slate-100 cursor-pointer select-none hover:bg-slate-750">
+          <Filter size={14} className="text-amber-400" />
+          <input
+            type="checkbox"
+            checked={lowStockOnly}
+            onChange={e => { setLowStockOnly(e.target.checked); setPage(0) }}
+            className="accent-amber-500"
+          />
+          Low Stock Only
+        </label>
+      </div>
+
+      {/* Loading / Error */}
+      {isLoading && (
+        <div className="text-center py-12 text-slate-400">Loading spools…</div>
+      )}
+      {error && (
+        <div className="text-center py-12 text-red-400">
+          Failed to load inventory.
+          <button onClick={() => refetch()} className="ml-2 underline hover:text-red-300">Retry</button>
+        </div>
+      )}
+
+      {/* Desktop Table */}
+      {!isLoading && !error && (
+        <>
+          <div className="hidden md:block overflow-x-auto rounded-lg border border-slate-700">
+            <table className="w-full text-sm">
+              <thead className="bg-slate-800 text-slate-300">
+                <tr>
+                  <th className="px-4 py-3 text-left font-semibold cursor-pointer select-none hover:text-slate-100" onClick={() => handleSort('name')}>
+                    Name <SortIndicator field="name" />
+                  </th>
+                  <th className="px-4 py-3 text-left font-semibold">Material</th>
+                  <th className="px-4 py-3 text-left font-semibold">Finish</th>
+                  <th className="px-4 py-3 text-left font-semibold">Color</th>
+                  <th className="px-4 py-3 text-right font-semibold cursor-pointer select-none hover:text-slate-100" onClick={() => handleSort('remaining_grams')}>
+                    Remaining <SortIndicator field="remaining_grams" />
+                  </th>
+                  <th className="px-4 py-3 text-right font-semibold cursor-pointer select-none hover:text-slate-100" onClick={() => handleSort('cost_usd')}>
+                    Cost <SortIndicator field="cost_usd" />
+                  </th>
+                  <th className="px-4 py-3 text-center font-semibold">Status</th>
+                  <th className="px-4 py-3 text-right font-semibold">Actions</th>
+                </tr>
+              </thead>
+              <tbody className="divide-y divide-slate-700">
+                {filtered.length === 0 && (
+                  <tr>
+                    <td colSpan={8} className="px-4 py-8 text-center text-slate-500">No spools found.</td>
+                  </tr>
+                )}
+                {filtered.map((spool: FilamentSpool) => {
+                  const isLow = spool.remaining_grams <= spool.low_stock_threshold_grams
+                  return (
+                    <tr key={spool.id} className={`${isLow ? 'bg-red-900/20' : 'bg-slate-800/50'} hover:bg-slate-700/50 transition-colors`}>
+                      <td className="px-4 py-3 font-medium text-slate-100">{spool.name}</td>
+                      <td className="px-4 py-3 text-slate-300">{spool.material_base?.name ?? '—'}</td>
+                      <td className="px-4 py-3 text-slate-300">{spool.material_finish?.name ?? '—'}</td>
+                      <td className="px-4 py-3">
+                        <div className="flex items-center gap-2">
+                          <ColorSwatch colorHex={spool.color_hex} size={20} />
+                          <span className="text-xs text-slate-400 uppercase">{spool.color_hex}</span>
+                        </div>
+                      </td>
+                      <td className="px-4 py-3 text-right tabular-nums text-slate-200">{spool.remaining_grams.toLocaleString()} g</td>
+                      <td className="px-4 py-3 text-right tabular-nums text-slate-300">{spool.cost_usd != null ? `$${spool.cost_usd.toFixed(2)}` : '—'}</td>
+                      <td className="px-4 py-3 text-center">
+                        {isLow ? (
+                          <span className="inline-flex items-center gap-1 rounded-full bg-red-900/50 border border-red-700 px-2 py-0.5 text-xs font-medium text-red-300">
+                            <AlertTriangle size={12} /> Low
+                          </span>
+                        ) : (
+                          <span className="inline-flex items-center rounded-full bg-emerald-900/30 border border-emerald-700 px-2 py-0.5 text-xs font-medium text-emerald-300">OK</span>
+                        )}
+                      </td>
+                      <td className="px-4 py-3 text-right">
+                        <div className="flex items-center justify-end gap-2">
+                          <button className="p-1.5 rounded hover:bg-slate-600 text-slate-400 hover:text-blue-400 transition-colors" title="Edit">
+                            <Pencil size={14} />
+                          </button>
+                          <button
+                            onClick={() => setDeleteId(spool.id)}
+                            className="p-1.5 rounded hover:bg-slate-600 text-slate-400 hover:text-red-400 transition-colors"
+                            title="Delete"
+                          >
+                            <Trash2 size={14} />
+                          </button>
+                        </div>
+                      </td>
+                    </tr>
+                  )
+                })}
+              </tbody>
+            </table>
+          </div>
+
+          {/* Mobile Cards */}
+          <div className="md:hidden space-y-3">
+            {filtered.length === 0 && (
+              <div className="text-center py-12 text-slate-500">No spools found.</div>
+            )}
+            {filtered.map((spool: FilamentSpool) => {
+              const isLow = spool.remaining_grams <= spool.low_stock_threshold_grams
+              return (
+                <div key={spool.id} className={`rounded-lg border ${isLow ? 'border-red-700 bg-red-900/10' : 'border-slate-700 bg-slate-800'} p-4 space-y-2`}>
+                  <div className="flex items-start justify-between">
+                    <div>
+                      <div className="font-semibold text-slate-100">{spool.name}</div>
+                      <div className="text-xs text-slate-400 mt-0.5">{spool.material_base?.name ?? '—'} · {spool.material_finish?.name ?? '—'}</div>
+                    </div>
+                    {isLow ? (
+                      <span className="inline-flex items-center gap-1 rounded-full bg-red-900/50 border border-red-700 px-2 py-0.5 text-xs font-medium text-red-300">
+                        <AlertTriangle size={12} /> Low
+                      </span>
+                    ) : (
+                      <span className="inline-flex items-center rounded-full bg-emerald-900/30 border border-emerald-700 px-2 py-0.5 text-xs font-medium text-emerald-300">OK</span>
+                    )}
+                  </div>
+
+                  <div className="flex items-center gap-3 text-sm">
+                    <div className="flex items-center gap-2">
+                      <ColorSwatch colorHex={spool.color_hex} size={20} />
+                      <span className="text-slate-400 uppercase text-xs">{spool.color_hex}</span>
+                    </div>
+                  </div>
+
+                  <div className="flex items-center justify-between text-sm">
+                    <span className="text-slate-400">Remaining: <span className="text-slate-200 font-medium tabular-nums">{spool.remaining_grams.toLocaleString()} g</span></span>
+                    <span className="text-slate-400">{spool.cost_usd != null ? `$${spool.cost_usd.toFixed(2)}` : '—'}</span>
+                  </div>
+
+                  <div className="flex items-center justify-end gap-2 pt-1">
+                    <button className="flex items-center gap-1 rounded-md bg-slate-700 px-3 py-1.5 text-xs font-medium text-slate-200 hover:bg-slate-600">
+                      <Pencil size={12} /> Edit
+                    </button>
+                    <button
+                      onClick={() => setDeleteId(spool.id)}
+                      className="flex items-center gap-1 rounded-md bg-red-900/30 border border-red-700 px-3 py-1.5 text-xs font-medium text-red-300 hover:bg-red-900/50"
+                    >
+                      <Trash2 size={12} /> Delete
+                    </button>
+                  </div>
+                </div>
+              )
+            })}
+          </div>
+
+          {/* Pagination */}
+          <div className="flex items-center justify-between pt-2">
+            <span className="text-sm text-slate-400">
+              Showing {page * PAGE_SIZE + 1}–{Math.min((page + 1) * PAGE_SIZE, total)} of {total}
+            </span>
+            <div className="flex items-center gap-2">
+              <button
+                onClick={() => setPage(p => Math.max(0, p - 1))}
+                disabled={page === 0}
+                className="p-2 rounded-lg bg-slate-800 border border-slate-700 text-slate-300 hover:bg-slate-700 disabled:opacity-40 disabled:cursor-not-allowed transition-colors"
+              >
+                <ChevronLeft size={16} />
+              </button>
+              <span className="text-sm text-slate-300 tabular-nums">{page + 1} / {totalPages}</span>
+              <button
+                onClick={() => setPage(p => Math.min(totalPages - 1, p + 1))}
+                disabled={page >= totalPages - 1}
+                className="p-2 rounded-lg bg-slate-800 border border-slate-700 text-slate-300 hover:bg-slate-700 disabled:opacity-40 disabled:cursor-not-allowed transition-colors"
+              >
+                <ChevronRight size={16} />
+              </button>
+            </div>
+          </div>
+        </>
+      )}
+
+      {/* Delete confirmation modal */}
+      {deleteId !== null && (
+        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/60 backdrop-blur-sm p-4">
+          <div className="w-full max-w-sm rounded-xl bg-slate-800 border border-slate-700 p-6 shadow-2xl space-y-4">
+            <div className="flex items-center gap-3">
+              <div className="flex h-10 w-10 items-center justify-center rounded-full bg-red-900/30">
+                <AlertTriangle size={20} className="text-red-400" />
+              </div>
+              <div>
+                <h3 className="text-lg font-semibold text-slate-100">Delete Spool?</h3>
+                <p className="text-sm text-slate-400">This action cannot be undone.</p>
+              </div>
+            </div>
+            <div className="flex justify-end gap-3">
+              <button
+                onClick={() => setDeleteId(null)}
+                className="rounded-lg bg-slate-700 px-4 py-2 text-sm font-medium text-slate-200 hover:bg-slate-600 transition-colors"
+              >
+                Cancel
+              </button>
+              <button
+                onClick={() => handleDelete(deleteId)}
+                className="rounded-lg bg-red-600 px-4 py-2 text-sm font-medium text-white hover:bg-red-500 transition-colors"
+              >
+                Delete
+              </button>
+            </div>
+          </div>
+        </div>
+      )}
+    </div>
+  )
+}

frontend/src/pages/PrintersPage.tsx

@@ -0,0 +1,262 @@
+import { useQuery } from '@tanstack/react-query'
+import { Printer, Wifi, WifiOff, HelpCircle, Plus, Globe, Radio } from 'lucide-react'
+import { fetchPrinters } from '../services/printerService'
+import LoadingSpinner from '../components/LoadingSpinner'
+import type { Printer as PrinterType, ConnectionStatus } from '../types/printer'
+
+function getConnectionStatus(printer: PrinterType): ConnectionStatus {
+  if (!printer.is_active) return 'offline'
+  if (printer.moonraker_url || printer.mqtt_broker_host) return 'online'
+  return 'unknown'
+}
+
+const statusConfig: Record<ConnectionStatus, { icon: typeof Wifi; label: string; className: string }> = {
+  online: {
+    icon: Wifi,
+    label: 'Online',
+    className: 'bg-emerald-900/30 border-emerald-700 text-emerald-300',
+  },
+  offline: {
+    icon: WifiOff,
+    label: 'Offline',
+    className: 'bg-red-900/30 border-red-700 text-red-300',
+  },
+  unknown: {
+    icon: HelpCircle,
+    label: 'Unknown',
+    className: 'bg-slate-700/50 border-slate-600 text-slate-400',
+  },
+}
+
+export default function PrintersPage() {
+  const { data: printers, isLoading, error, refetch } = useQuery({
+    queryKey: ['printers'],
+    queryFn: fetchPrinters,
+  })
+
+  const count = printers?.length ?? 0
+
+  return (
+    <div className="space-y-4">
+      {/* Header */}
+      <div className="flex flex-col sm:flex-row sm:items-center sm:justify-between gap-3">
+        <div>
+          <h2 className="text-xl font-bold text-slate-100">Printers</h2>
+          <p className="text-sm text-slate-400">{count} printer(s) in fleet</p>
+        </div>
+        <button className="inline-flex items-center gap-2 rounded-lg bg-emerald-600 px-4 py-2 text-sm font-semibold text-white hover:bg-emerald-500 active:bg-emerald-700 transition-colors">
+          <Plus size={16} /> Add Printer
+        </button>
+      </div>
+
+      {/* Loading */}
+      {isLoading && (
+        <div className="flex items-center justify-center py-16">
+          <LoadingSpinner />
+        </div>
+      )}
+
+      {/* Error */}
+      {error && (
+        <div className="rounded-lg border border-red-700 bg-red-900/20 p-6 text-center">
+          <p className="text-red-400 mb-2">Failed to load printers.</p>
+          <button
+            onClick={() => refetch()}
+            className="text-sm text-red-300 underline hover:text-red-200"
+          >
+            Retry
+          </button>
+        </div>
+      )}
+
+      {/* Empty */}
+      {!isLoading && !error && printers?.length === 0 && (
+        <div className="rounded-lg border border-slate-700 bg-slate-800 p-12 text-center">
+          <Printer size={40} className="mx-auto mb-3 text-slate-500" />
+          <p className="text-slate-400">No printers found.</p>
+          <p className="text-sm text-slate-500 mt-1">
+            Add a printer to start monitoring your fleet.
+          </p>
+        </div>
+      )}
+
+      {/* Desktop Table */}
+      {!isLoading && !error && (printers?.length ?? 0) > 0 && (
+        <>
+          <div className="hidden lg:block overflow-x-auto rounded-lg border border-slate-700">
+            <table className="w-full text-sm">
+              <thead className="bg-slate-800 text-slate-300">
+                <tr>
+                  <th className="px-4 py-3 text-left font-semibold">Name</th>
+                  <th className="px-4 py-3 text-left font-semibold">Type</th>
+                  <th className="px-4 py-3 text-left font-semibold">Manufacturer</th>
+                  <th className="px-4 py-3 text-left font-semibold">Model</th>
+                  <th className="px-4 py-3 text-center font-semibold">Status</th>
+                  <th className="px-4 py-3 text-left font-semibold">Moonraker</th>
+                  <th className="px-4 py-3 text-left font-semibold">MQTT</th>
+                </tr>
+              </thead>
+              <tbody className="divide-y divide-slate-700">
+                {printers!.map((printer) => {
+                  const status = getConnectionStatus(printer)
+                  const StatusIcon = statusConfig[status].icon
+                  return (
+                    <tr
+                      key={printer.id}
+                      className="bg-slate-800/50 hover:bg-slate-700/50 transition-colors"
+                    >
+                      <td className="px-4 py-3 font-medium text-slate-100">
+                        {printer.name}
+                      </td>
+                      <td className="px-4 py-3 text-slate-300">
+                        {printer.printer_type?.name ?? '—'}
+                      </td>
+                      <td className="px-4 py-3 text-slate-300">
+                        {printer.manufacturer || '—'}
+                      </td>
+                      <td className="px-4 py-3 text-slate-300">
+                        {printer.model || '—'}
+                      </td>
+                      <td className="px-4 py-3 text-center">
+                        <span
+                          className={`inline-flex items-center gap-1.5 rounded-full border px-2.5 py-0.5 text-xs font-medium ${statusConfig[status].className}`}
+                        >
+                          <StatusIcon size={12} />
+                          {statusConfig[status].label}
+                        </span>
+                      </td>
+                      <td className="px-4 py-3">
+                        {printer.moonraker_url ? (
+                          <a
+                            href={printer.moonraker_url}
+                            target="_blank"
+                            rel="noopener noreferrer"
+                            className="inline-flex items-center gap-1.5 text-sky-400 hover:text-sky-300 text-xs truncate max-w-[180px]"
+                            title={printer.moonraker_url}
+                          >
+                            <Globe size={12} className="shrink-0" />
+                            {printer.moonraker_url}
+                          </a>
+                        ) : (
+                          <span className="text-slate-500 text-xs">—</span>
+                        )}
+                      </td>
+                      <td className="px-4 py-3">
+                        {printer.mqtt_broker_host ? (
+                          <div className="space-y-0.5">
+                            <div className="inline-flex items-center gap-1.5 text-xs text-slate-300">
+                              <Radio size={12} className="shrink-0 text-amber-400" />
+                              <span className="truncate max-w-[140px]" title={printer.mqtt_broker_host}>
+                                {printer.mqtt_broker_host}
+                              </span>
+                            </div>
+                            {printer.mqtt_topic_prefix && (
+                              <div className="text-xs text-slate-500 ml-[20px] truncate max-w-[140px]" title={printer.mqtt_topic_prefix}>
+                                topic: {printer.mqtt_topic_prefix}
+                              </div>
+                            )}
+                            <div className="text-xs text-slate-500 ml-[20px]">
+                              TLS: {printer.mqtt_tls_enabled ? 'on' : 'off'}
+                            </div>
+                          </div>
+                        ) : (
+                          <span className="text-slate-500 text-xs">—</span>
+                        )}
+                      </td>
+                    </tr>
+                  )
+                })}
+              </tbody>
+            </table>
+          </div>
+
+          {/* Mobile / Tablet Cards */}
+          <div className="lg:hidden space-y-3">
+            {printers!.map((printer) => {
+              const status = getConnectionStatus(printer)
+              const StatusIcon = statusConfig[status].icon
+              return (
+                <div
+                  key={printer.id}
+                  className="rounded-lg border border-slate-700 bg-slate-800 p-4 space-y-3"
+                >
+                  {/* Top row: name + status */}
+                  <div className="flex items-start justify-between gap-3">
+                    <div className="min-w-0">
+                      <div className="font-semibold text-slate-100 truncate">
+                        {printer.name}
+                      </div>
+                      <div className="text-xs text-slate-400 mt-0.5">
+                        {[
+                          printer.printer_type?.name,
+                          printer.manufacturer,
+                          printer.model,
+                        ]
+                          .filter(Boolean)
+                          .join(' · ') || 'No details'}
+                      </div>
+                    </div>
+                    <span
+                      className={`inline-flex items-center gap-1.5 rounded-full border px-2.5 py-0.5 text-xs font-medium shrink-0 ${statusConfig[status].className}`}
+                    >
+                      <StatusIcon size={12} />
+                      {statusConfig[status].label}
+                    </span>
+                  </div>
+
+                  {/* Connection details */}
+                  <div className="grid grid-cols-1 sm:grid-cols-2 gap-3">
+                    {/* Moonraker */}
+                    <div className="rounded-md bg-slate-900/50 p-3 min-w-0">
+                      <div className="flex items-center gap-1.5 text-xs text-slate-400 mb-1">
+                        <Globe size={12} />
+                        Moonraker
+                      </div>
+                      {printer.moonraker_url ? (
+                        <a
+                          href={printer.moonraker_url}
+                          target="_blank"
+                          rel="noopener noreferrer"
+                          className="text-xs text-sky-400 hover:text-sky-300 break-all"
+                        >
+                          {printer.moonraker_url}
+                        </a>
+                      ) : (
+                        <span className="text-xs text-slate-500">Not configured</span>
+                      )}
+                    </div>
+
+                    {/* MQTT */}
+                    <div className="rounded-md bg-slate-900/50 p-3 min-w-0">
+                      <div className="flex items-center gap-1.5 text-xs text-slate-400 mb-1">
+                        <Radio size={12} />
+                        MQTT
+                      </div>
+                      {printer.mqtt_broker_host ? (
+                        <div className="space-y-0.5 text-xs text-slate-300">
+                          <div className="truncate" title={printer.mqtt_broker_host}>
+                            {printer.mqtt_broker_host}
+                          </div>
+                          {printer.mqtt_topic_prefix && (
+                            <div className="text-slate-500 truncate" title={printer.mqtt_topic_prefix}>
+                              topic: {printer.mqtt_topic_prefix}
+                            </div>
+                          )}
+                          <div className="text-slate-500">
+                            TLS: {printer.mqtt_tls_enabled ? 'on' : 'off'}
+                          </div>
+                        </div>
+                      ) : (
+                        <span className="text-xs text-slate-500">Not configured</span>
+                      )}
+                    </div>
+                  </div>
+                </div>
+              )
+            })}
+          </div>
+        </>
+      )}
+    </div>
+  )
+}

frontend/src/services/filamentService.ts

@@ -0,0 +1,24 @@
+import axios from 'axios'
+import type { FilamentSpool, ListResponse, FilamentFilter } from '../types/filament'
+
+const API_BASE = '/api'
+
+export async function fetchFilaments(filter: FilamentFilter): Promise<ListResponse<FilamentSpool>> {
+  const params = new URLSearchParams()
+  if (filter.material) params.set('material', filter.material)
+  if (filter.finish) params.set('finish', filter.finish)
+  if (filter.color) params.set('color', filter.color)
+  if (filter.low_stock) params.set('low_stock', 'true')
+  if (filter.search) params.set('search', filter.search)
+  if (filter.sort_by) params.set('sort_by', filter.sort_by)
+  if (filter.sort_dir) params.set('sort_dir', filter.sort_dir)
+  if (filter.limit !== undefined) params.set('limit', String(filter.limit))
+  if (filter.offset !== undefined) params.set('offset', String(filter.offset))
+
+  const res = await axios.get<ListResponse<FilamentSpool>>(`${API_BASE}/filaments?${params.toString()}`)
+  return res.data
+}
+
+export async function deleteFilament(id: number): Promise<void> {
+  await axios.delete(`${API_BASE}/filaments/${id}`)
+}

frontend/src/services/printerService.ts

@@ -0,0 +1,9 @@
+import axios from 'axios'
+import type { Printer, PrinterResponse } from '../types/printer'
+
+const API_BASE = '/api'
+
+export async function fetchPrinters(): Promise<Printer[]> {
+  const res = await axios.get<PrinterResponse>(`${API_BASE}/printers`)
+  return res.data.data
+}

frontend/src/types/filament.ts

@@ -0,0 +1,72 @@
+// Extrudex domain types
+
+export interface MaterialBase {
+  id: number
+  name: string
+  density_g_cm3: number
+  extrusion_temp_min?: number
+  extrusion_temp_max?: number
+  bed_temp_min?: number
+  bed_temp_max?: number
+  created_at: string
+  updated_at: string
+}
+
+export interface MaterialFinish {
+  id: number
+  name: string
+  description?: string
+  created_at: string
+  updated_at: string
+}
+
+export interface MaterialModifier {
+  id: number
+  name: string
+  description?: string
+  created_at: string
+  updated_at: string
+}
+
+export interface FilamentSpool {
+  id: number
+  name: string
+  material_base_id: number
+  material_base?: MaterialBase
+  material_finish_id: number
+  material_finish?: MaterialFinish
+  material_modifier_id?: number
+  material_modifier?: MaterialModifier
+  color_hex: string
+  brand?: string
+  diameter_mm: number
+  initial_grams: number
+  remaining_grams: number
+  spool_weight_grams?: number
+  cost_usd?: number
+  low_stock_threshold_grams: number
+  notes?: string
+  barcode?: string
+  deleted_at?: string
+  created_at: string
+  updated_at: string
+}
+
+export interface ListResponse<T> {
+  data: T[]
+  total: number
+  limit: number
+  offset: number
+}
+
+export interface FilamentFilter {
+  material?: string
+  finish?: string
+  color?: string
+  low_stock?: boolean
+  search?: string
+  sort_by?: string
+  sort_dir?: 'asc' | 'desc'
+  limit?: number
+  offset?: number
+}

frontend/src/types/printer.ts

@@ -0,0 +1,29 @@
+export interface PrinterType {
+  id: number
+  name: string
+  created_at: string
+  updated_at: string
+}
+
+export interface Printer {
+  id: number
+  name: string
+  printer_type_id: number
+  printer_type?: PrinterType
+  manufacturer?: string
+  model?: string
+  moonraker_url?: string
+  moonraker_api_key?: string
+  mqtt_broker_host?: string
+  mqtt_topic_prefix?: string
+  mqtt_tls_enabled: boolean
+  is_active: boolean
+  created_at: string
+  updated_at: string
+}
+
+export type ConnectionStatus = 'online' | 'offline' | 'unknown'
+
+export interface PrinterResponse {
+  data: Printer[]
+}