docs: add frontend UI architecture and ComfyUI widget guidelines

- Document dual UI systems: standalone web UI and ComfyUI custom node widgets
- Add ComfyUI widget development guidelines including styling and constraints
- Update terminology in LoraRandomizerNode from 'frontend/backend' to 'fixed/always' for clarity
- Include UI constraints for ComfyUI widgets: minimize vertical space, avoid dynamic height changes, keep UI simple

vue-widgets/src/components/LoraRandomizerWidget.vue

@@ -13,6 +13,9 @@
       :roll-mode="state.rollMode.value"
       :is-rolling="state.isRolling.value"
       :is-clip-strength-disabled="state.isClipStrengthDisabled.value"
+      :last-used="state.lastUsed.value"
+      :current-loras="currentLoras"
+      :can-reuse-last="canReuseLast"
       @update:count-mode="state.countMode.value = $event"
       @update:count-fixed="state.countFixed.value = $event"
       @update:count-min="state.countMin.value = $event"
@@ -23,13 +26,15 @@
       @update:clip-strength-min="state.clipStrengthMin.value = $event"
       @update:clip-strength-max="state.clipStrengthMax.value = $event"
       @update:roll-mode="state.rollMode.value = $event"
-      @roll="handleRoll"
+      @generate-fixed="handleGenerateFixed"
+      @always-randomize="handleAlwaysRandomize"
+      @reuse-last="handleReuseLast"
     />
   </div>
 </template>
 
 <script setup lang="ts">
-import { onMounted } from 'vue'
+import { onMounted, computed, ref, watch } from 'vue'
 import LoraRandomizerSettingsView from './lora-randomizer/LoraRandomizerSettingsView.vue'
 import { useLoraRandomizerState } from '../composables/useLoraRandomizerState'
 import type { ComponentWidget, RandomizerConfig, LoraEntry } from '../composables/types'
@@ -43,11 +48,31 @@ const props = defineProps<{
 // State management
 const state = useLoraRandomizerState(props.widget)
 
-// Handle roll button click
-const handleRoll = async () => {
-  try {
-    console.log('[LoraRandomizerWidget] Roll button clicked')
+// Track current loras from the loras widget
+const currentLoras = ref<LoraEntry[]>([])
 
+// Computed property to check if we can reuse last
+const canReuseLast = computed(() => {
+  const lastUsed = state.lastUsed.value
+  if (!lastUsed || lastUsed.length === 0) return false
+  return !areLorasEqual(currentLoras.value, lastUsed)
+})
+
+// Helper function to compare two lora lists
+const areLorasEqual = (a: LoraEntry[], b: LoraEntry[]): boolean => {
+  if (a.length !== b.length) return false
+  const sortedA = [...a].sort((x, y) => x.name.localeCompare(y.name))
+  const sortedB = [...b].sort((x, y) => x.name.localeCompare(y.name))
+  return sortedA.every((lora, i) =>
+    lora.name === sortedB[i].name &&
+    lora.strength === sortedB[i].strength &&
+    lora.clipStrength === sortedB[i].clipStrength
+  )
+}
+
+// Handle "Generate Fixed" button click
+const handleGenerateFixed = async () => {
+  try {
     // Get pool config from connected pool_config input
     const poolConfig = (props.node as any).getPoolConfig?.() || null
 
@@ -55,46 +80,116 @@ const handleRoll = async () => {
     const lorasWidget = props.node.widgets?.find((w: any) => w.name === "loras")
     const lockedLoras: LoraEntry[] = (lorasWidget?.value || []).filter((lora: LoraEntry) => lora.locked === true)
 
-    console.log('[LoraRandomizerWidget] Pool config:', poolConfig)
-    console.log('[LoraRandomizerWidget] Locked loras:', lockedLoras)
+    // Call API to get random loras
+    const randomLoras = await state.rollLoras(poolConfig, lockedLoras)
+
+    // Update the loras widget with the new selection
+    if (lorasWidget) {
+      lorasWidget.value = randomLoras
+      currentLoras.value = randomLoras
+    }
+
+    // Set roll mode to fixed
+    state.rollMode.value = 'fixed'
+  } catch (error) {
+    console.error('[LoraRandomizerWidget] Error generating fixed LoRAs:', error)
+    alert('Failed to generate LoRAs: ' + (error as Error).message)
+  }
+}
+
+// Handle "Always Randomize" button click
+const handleAlwaysRandomize = async () => {
+  try {
+    // Get pool config from connected pool_config input
+    const poolConfig = (props.node as any).getPoolConfig?.() || null
+
+    // Get locked loras from the loras widget
+    const lorasWidget = props.node.widgets?.find((w: any) => w.name === "loras")
+    const lockedLoras: LoraEntry[] = (lorasWidget?.value || []).filter((lora: LoraEntry) => lora.locked === true)
 
     // Call API to get random loras
     const randomLoras = await state.rollLoras(poolConfig, lockedLoras)
 
-    console.log('[LoraRandomizerWidget] Got random LoRAs:', randomLoras)
-
     // Update the loras widget with the new selection
-    // This will be handled by emitting an event or directly updating the loras widget
-    // For now, we'll emit a custom event that the parent widget handler can catch
-    if (typeof (props.widget as any).onRoll === 'function') {
-      (props.widget as any).onRoll(randomLoras)
+    if (lorasWidget) {
+      lorasWidget.value = randomLoras
+      currentLoras.value = randomLoras
     }
+
+    // Set roll mode to always
+    state.rollMode.value = 'always'
   } catch (error) {
-    console.error('[LoraRandomizerWidget] Error rolling LoRAs:', error)
-    alert('Failed to roll LoRAs: ' + (error as Error).message)
+    console.error('[LoraRandomizerWidget] Error generating random LoRAs:', error)
+    alert('Failed to generate LoRAs: ' + (error as Error).message)
   }
 }
 
+// Handle "Reuse Last" button click
+const handleReuseLast = () => {
+  const lastUsedLoras = state.useLastUsed()
+  if (lastUsedLoras) {
+    // Update the loras widget with the last used combination
+    const lorasWidget = props.node.widgets?.find((w: any) => w.name === 'loras')
+    if (lorasWidget) {
+      lorasWidget.value = lastUsedLoras
+      currentLoras.value = lastUsedLoras
+    }
+
+    // Switch to fixed mode
+    state.rollMode.value = 'fixed'
+  }
+}
+
+// Watch for changes to the loras widget to track current loras
+watch(() => props.node.widgets?.find((w: any) => w.name === 'loras')?.value, (newVal) => {
+  if (newVal && Array.isArray(newVal)) {
+    currentLoras.value = newVal
+  }
+}, { immediate: true, deep: true })
+
 // Lifecycle
 onMounted(async () => {
   // Setup serialization
   props.widget.serializeValue = async () => {
     const config = state.buildConfig()
-    console.log('[LoraRandomizerWidget] Serializing config:', config)
     return config
   }
 
   // Handle external value updates (e.g., loading workflow, paste)
   props.widget.onSetValue = (v) => {
-    console.log('[LoraRandomizerWidget] Restoring from config:', v)
     state.restoreFromConfig(v as RandomizerConfig)
   }
 
   // Restore from saved value
   if (props.widget.value) {
-    console.log('[LoraRandomizerWidget] Restoring from saved value:', props.widget.value)
     state.restoreFromConfig(props.widget.value as RandomizerConfig)
   }
+
+  // Override onExecuted to handle backend UI updates
+  const originalOnExecuted = (props.node as any).onExecuted?.bind(props.node)
+
+  ;(props.node as any).onExecuted = function(output: any) {
+    console.log("[LoraRandomizerWidget] Node executed with output:", output)
+
+    // Update last_used from backend
+    if (output?.last_used !== undefined) {
+      state.lastUsed.value = output.last_used
+      console.log(`[LoraRandomizerWidget] Updated last_used: ${output.last_used ? output.last_used.length : 0} LoRAs`)
+    }
+
+    // Update loras widget if backend provided new loras
+    const lorasWidget = props.node.widgets?.find((w: any) => w.name === 'loras')
+    if (lorasWidget && output?.loras && Array.isArray(output.loras)) {
+      console.log("[LoraRandomizerWidget] Received loras data from backend:", output.loras)
+      lorasWidget.value = output.loras
+      currentLoras.value = output.loras
+    }
+
+    // Call original onExecuted if it exists
+    if (originalOnExecuted) {
+      return originalOnExecuted(output)
+    }
+  }
 })
 </script>
 

vue-widgets/src/components/lora-randomizer/LastUsedPreview.vue

@@ -0,0 +1,155 @@
+<template>
+  <div class="last-used-preview">
+    <div class="last-used-preview__content">
+      <div
+        v-for="lora in displayLoras"
+        :key="lora.name"
+        class="last-used-preview__item"
+      >
+        <img
+          v-if="previewUrls[lora.name]"
+          :src="previewUrls[lora.name]"
+          class="last-used-preview__thumb"
+          @error="onImageError(lora.name)"
+        />
+        <div v-else class="last-used-preview__thumb last-used-preview__thumb--placeholder">
+          <svg viewBox="0 0 16 16" fill="currentColor">
+            <path d="M6.002 5.5a1.5 1.5 0 1 1-3 0 1.5 1.5 0 0 1 3 0z"/>
+            <path d="M2.002 1a2 2 0 0 0-2 2v10a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V3a2 2 0 0 0-2-2h-12zm12 1a1 1 0 0 1 1 1v6.5l-3.777-1.947a.5.5 0 0 0-.577.093l-3.71 3.71-2.66-1.772a.5.5 0 0 0-.63.062L1.002 12V3a1 1 0 0 1 1-1h12z"/>
+          </svg>
+        </div>
+        <div class="last-used-preview__info">
+          <span class="last-used-preview__name">{{ lora.name }}</span>
+          <span class="last-used-preview__strength">
+            M: {{ lora.strength }}{{ lora.clipStrength !== undefined ? ` / C: ${lora.clipStrength}` : '' }}
+          </span>
+        </div>
+      </div>
+      <div v-if="loras.length > 5" class="last-used-preview__more">
+        +{{ (loras.length - 5).toLocaleString() }} more LoRAs
+      </div>
+    </div>
+  </div>
+</template>
+
+<script setup lang="ts">
+import { ref, computed } from 'vue'
+import type { LoraEntry } from '../../composables/types'
+
+const props = defineProps<{
+  loras: LoraEntry[]
+}>()
+
+const displayLoras = computed(() => props.loras.slice(0, 5))
+
+// Preview URLs cache
+const previewUrls = ref<Record<string, string>>({})
+
+// Fetch preview URL for a lora using API
+const fetchPreviewUrl = async (loraName: string) => {
+  try {
+    const response = await fetch(`/api/lm/loras/preview-url?name=${encodeURIComponent(loraName)}`)
+
+    if (response.ok) {
+      const data = await response.json()
+      if (data.preview_url) {
+        previewUrls.value[loraName] = data.preview_url
+      }
+    }
+  } catch (error) {
+    // Silent fail, just use placeholder
+  }
+}
+
+// Load preview URLs on mount
+props.loras.forEach(lora => {
+  fetchPreviewUrl(lora.name)
+})
+
+const onImageError = (loraName: string) => {
+  previewUrls.value[loraName] = ''
+}
+</script>
+
+<style scoped>
+.last-used-preview {
+  position: absolute;
+  bottom: 100%;
+  right: 0;
+  margin-bottom: 8px;
+  z-index: 100;
+  width: 280px;
+}
+
+.last-used-preview__content {
+  background: var(--comfy-menu-bg, #1a1a1a);
+  border: 1px solid var(--border-color, #444);
+  border-radius: 6px;
+  padding: 8px;
+  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
+  display: flex;
+  flex-direction: column;
+  gap: 4px;
+}
+
+.last-used-preview__item {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  padding: 4px 6px;
+  background: var(--comfy-input-bg, #333);
+  border-radius: 4px;
+}
+
+.last-used-preview__thumb {
+  width: 28px;
+  height: 28px;
+  object-fit: cover;
+  border-radius: 3px;
+  flex-shrink: 0;
+  background: rgba(0, 0, 0, 0.2);
+}
+
+.last-used-preview__thumb--placeholder {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  color: var(--fg-color, #fff);
+  opacity: 0.2;
+}
+
+.last-used-preview__thumb--placeholder svg {
+  width: 14px;
+  height: 14px;
+}
+
+.last-used-preview__info {
+  flex: 1;
+  display: flex;
+  flex-direction: column;
+  gap: 1px;
+  min-width: 0;
+}
+
+.last-used-preview__name {
+  font-size: 11px;
+  color: var(--fg-color, #fff);
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.last-used-preview__strength {
+  font-size: 10px;
+  color: var(--fg-color, #fff);
+  opacity: 0.5;
+}
+
+.last-used-preview__more {
+  font-size: 11px;
+  color: var(--fg-color, #fff);
+  opacity: 0.5;
+  text-align: center;
+  padding: 4px;
+}
+</style>

vue-widgets/src/components/lora-randomizer/LoraRandomizerSettingsView.vue

@@ -135,48 +135,73 @@
       </div>
     </div>
 
-    <!-- Roll Mode -->
+    <!-- Roll Mode - New 3-button design -->
     <div class="setting-section">
       <label class="setting-label">Roll Mode</label>
-      <div class="roll-mode-selector">
-        <label class="radio-label">
-          <input
-            type="radio"
-            name="roll-mode"
-            value="frontend"
-            :checked="rollMode === 'frontend'"
-            @change="$emit('update:rollMode', 'frontend')"
+      <div class="roll-buttons-with-tooltip">
+        <div class="roll-buttons">
+          <button
+            class="roll-button"
+            :class="{ selected: rollMode === 'fixed' }"
+            :disabled="isRolling"
+            @click="$emit('generate-fixed')"
+          >
+            <svg class="roll-button__icon" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+              <rect x="2" y="2" width="20" height="20" rx="5"/>
+              <circle cx="12" cy="12" r="3"/>
+              <circle cx="6" cy="8" r="1.5"/>
+              <circle cx="18" cy="16" r="1.5"/>
+            </svg>
+            <span class="roll-button__text">Generate Fixed</span>
+          </button>
+          <button
+            class="roll-button"
+            :class="{ selected: rollMode === 'always' }"
+            :disabled="isRolling"
+            @click="$emit('always-randomize')"
+          >
+            <svg class="roll-button__icon" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+              <path d="M21 12a9 9 0 1 1-6.219-8.56"/>
+              <path d="M21 3v5h-5"/>
+              <circle cx="12" cy="12" r="3"/>
+              <circle cx="6" cy="8" r="1.5"/>
+              <circle cx="18" cy="16" r="1.5"/>
+            </svg>
+            <span class="roll-button__text">Always Randomize</span>
+          </button>
+          <button
+            class="roll-button"
+            :class="{ selected: rollMode === 'fixed' && canReuseLast && areLorasEqual(currentLoras, lastUsed) }"
+            :disabled="!canReuseLast"
+            @mouseenter="showTooltip = true"
+            @mouseleave="showTooltip = false"
+            @click="$emit('reuse-last')"
+          >
+            <svg class="roll-button__icon" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+              <path d="M9 14 4 9l5-5"/>
+              <path d="M4 9h10.5a5.5 5.5 0 0 1 5.5 5.5v0a5.5 5.5 0 0 1-5.5 5.5H11"/>
+            </svg>
+            <span class="roll-button__text">Reuse Last</span>
+          </button>
+        </div>
+
+        <!-- Last Used Preview Tooltip -->
+        <Transition name="tooltip">
+          <LastUsedPreview
+            v-if="showTooltip && lastUsed && lastUsed.length > 0"
+            :loras="lastUsed"
           />
-          <span>Frontend Roll (fixed until re-rolled)</span>
-        </label>
-        <button
-          class="roll-button"
-          :disabled="rollMode !== 'frontend' || isRolling"
-          @click="$emit('roll')"
-        >
-          <span class="roll-button__content">
-            <svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><rect width="18" height="18" x="3" y="3" rx="2" ry="2"></rect><path d="M8 8h.01"></path><path d="M16 16h.01"></path><path d="M16 8h.01"></path><path d="M8 16h.01"></path></svg>
-            Roll
-          </span>
-        </button>
-      </div>
-      <div class="roll-mode-selector">
-        <label class="radio-label">
-          <input
-            type="radio"
-            name="roll-mode"
-            value="backend"
-            :checked="rollMode === 'backend'"
-            @change="$emit('update:rollMode', 'backend')"
-          />
-          <span>Backend Roll (randomizes each execution)</span>
-        </label>
+        </Transition>
       </div>
     </div>
   </div>
 </template>
 
 <script setup lang="ts">
+import { ref } from 'vue'
+import LastUsedPreview from './LastUsedPreview.vue'
+import type { LoraEntry } from '../../composables/types'
+
 defineProps<{
   countMode: 'fixed' | 'range'
   countFixed: number
@@ -187,9 +212,12 @@ defineProps<{
   useSameClipStrength: boolean
   clipStrengthMin: number
   clipStrengthMax: number
-  rollMode: 'frontend' | 'backend'
+  rollMode: 'fixed' | 'always'
   isRolling: boolean
   isClipStrengthDisabled: boolean
+  lastUsed: LoraEntry[] | null
+  currentLoras: LoraEntry[]
+  canReuseLast: boolean
 }>()
 
 defineEmits<{
@@ -202,9 +230,25 @@ defineEmits<{
   'update:useSameClipStrength': [value: boolean]
   'update:clipStrengthMin': [value: number]
   'update:clipStrengthMax': [value: number]
-  'update:rollMode': [value: 'frontend' | 'backend']
-  roll: []
+  'update:rollMode': [value: 'fixed' | 'always']
+  'generate-fixed': []
+  'always-randomize': []
+  'reuse-last': []
 }>()
+
+const showTooltip = ref(false)
+
+const areLorasEqual = (a: LoraEntry[] | null, b: LoraEntry[] | null): boolean => {
+  if (!a || !b) return false
+  if (a.length !== b.length) return false
+  const sortedA = [...a].sort((x, y) => x.name.localeCompare(y.name))
+  const sortedB = [...b].sort((x, y) => x.name.localeCompare(y.name))
+  return sortedA.every((lora, i) =>
+    lora.name === sortedB[i].name &&
+    lora.strength === sortedB[i].strength &&
+    lora.clipStrength === sortedB[i].clipStrength
+  )
+}
 </script>
 
 <style scoped>
@@ -330,41 +374,75 @@ defineEmits<{
   cursor: pointer;
 }
 
+/* Roll buttons with tooltip container */
+.roll-buttons-with-tooltip {
+  position: relative;
+}
+
+/* Roll buttons container */
+.roll-buttons {
+  display: grid;
+  grid-template-columns: 1fr 1fr 1fr;
+  gap: 8px;
+}
+
 .roll-button {
-  padding: 8px 16px;
-  background: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%);
-  border: none;
+  padding: 8px 10px;
+  background: rgba(30, 30, 36, 0.6);
+  border: 1px solid rgba(255, 255, 255, 0.1);
   border-radius: 4px;
-  color: white;
-  font-size: 13px;
+  display: flex;
+  flex-direction: row;
+  align-items: center;
+  justify-content: center;
+  gap: 6px;
+  color: #e4e4e7;
+  font-size: 11px;
   font-weight: 500;
   cursor: pointer;
   transition: all 0.2s;
   white-space: nowrap;
-  display: flex;
-  align-items: center;
-  justify-content: center;
 }
 
 .roll-button:hover:not(:disabled) {
-  background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
-  transform: translateY(-1px);
-  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
+  background: rgba(66, 153, 225, 0.2);
+  border-color: rgba(66, 153, 225, 0.4);
+  color: #bfdbfe;
 }
 
-.roll-button:active:not(:disabled) {
-  transform: translateY(0);
+.roll-button.selected {
+  background: rgba(66, 153, 225, 0.3);
+  border-color: rgba(66, 153, 225, 0.6);
+  color: #e4e4e7;
+  box-shadow: 0 0 0 1px rgba(66, 153, 225, 0.3);
 }
 
 .roll-button:disabled {
-  opacity: 0.5;
+  opacity: 0.4;
   cursor: not-allowed;
-  background: linear-gradient(135deg, #52525b 0%, #3f3f46 100%);
 }
 
-.roll-button__content {
-  display: inline-flex;
-  align-items: center;
-  gap: 6px;
+.roll-button__icon {
+  width: 20px;
+  height: 20px;
+  flex-shrink: 0;
+}
+
+.roll-button__text {
+  font-size: 11px;
+  text-align: center;
+  line-height: 1.2;
+}
+
+/* Tooltip transitions */
+.tooltip-enter-active,
+.tooltip-leave-active {
+  transition: opacity 0.15s ease, transform 0.15s ease;
+}
+
+.tooltip-enter-from,
+.tooltip-leave-to {
+  opacity: 0;
+  transform: translateY(4px);
 }
 </style>