Telegram: add inline button model selection for /models and /model commands

src/telegram/model-buttons.ts

@@ -0,0 +1,210 @@
+/**
+ * Telegram inline button utilities for model selection.
+ *
+ * Callback data patterns (max 64 bytes for Telegram):
+ * - mdl_prov              - show providers list
+ * - mdl_list_{prov}_{pg}  - show models for provider (page N, 1-indexed)
+ * - mdl_sel_{provider/id} - select model
+ * - mdl_back              - back to providers list
+ */
+
+export type ButtonRow = Array<{ text: string; callback_data: string }>;
+
+export type ParsedModelCallback =
+  | { type: "providers" }
+  | { type: "list"; provider: string; page: number }
+  | { type: "select"; provider: string; model: string }
+  | { type: "back" };
+
+export type ProviderInfo = {
+  id: string;
+  count: number;
+};
+
+export type ModelsKeyboardParams = {
+  provider: string;
+  models: string[];
+  currentModel?: string;
+  currentPage: number;
+  totalPages: number;
+  pageSize?: number;
+};
+
+const MODELS_PAGE_SIZE = 8;
+
+/**
+ * Parse a model callback_data string into a structured object.
+ * Returns null if the data doesn't match a known pattern.
+ */
+export function parseModelCallbackData(data: string): ParsedModelCallback | null {
+  const trimmed = data.trim();
+  if (!trimmed.startsWith("mdl_")) {
+    return null;
+  }
+
+  if (trimmed === "mdl_prov" || trimmed === "mdl_back") {
+    return { type: trimmed === "mdl_prov" ? "providers" : "back" };
+  }
+
+  // mdl_list_{provider}_{page}
+  const listMatch = trimmed.match(/^mdl_list_([a-z0-9_-]+)_(\d+)$/i);
+  if (listMatch) {
+    const [, provider, pageStr] = listMatch;
+    const page = Number.parseInt(pageStr ?? "1", 10);
+    if (provider && Number.isFinite(page) && page >= 1) {
+      return { type: "list", provider, page };
+    }
+  }
+
+  // mdl_sel_{provider/model}
+  const selMatch = trimmed.match(/^mdl_sel_(.+)$/);
+  if (selMatch) {
+    const modelRef = selMatch[1];
+    if (modelRef) {
+      const slashIndex = modelRef.indexOf("/");
+      if (slashIndex > 0 && slashIndex < modelRef.length - 1) {
+        return {
+          type: "select",
+          provider: modelRef.slice(0, slashIndex),
+          model: modelRef.slice(slashIndex + 1),
+        };
+      }
+    }
+  }
+
+  return null;
+}
+
+/**
+ * Build provider selection keyboard with 2 providers per row.
+ */
+export function buildProviderKeyboard(providers: ProviderInfo[]): ButtonRow[] {
+  if (providers.length === 0) {
+    return [];
+  }
+
+  const rows: ButtonRow[] = [];
+  let currentRow: ButtonRow = [];
+
+  for (const provider of providers) {
+    const button = {
+      text: `${provider.id} (${provider.count})`,
+      callback_data: `mdl_list_${provider.id}_1`,
+    };
+
+    currentRow.push(button);
+
+    if (currentRow.length === 2) {
+      rows.push(currentRow);
+      currentRow = [];
+    }
+  }
+
+  // Push any remaining button
+  if (currentRow.length > 0) {
+    rows.push(currentRow);
+  }
+
+  return rows;
+}
+
+/**
+ * Build model list keyboard with pagination and back button.
+ */
+export function buildModelsKeyboard(params: ModelsKeyboardParams): ButtonRow[] {
+  const { provider, models, currentModel, currentPage, totalPages } = params;
+  const pageSize = params.pageSize ?? MODELS_PAGE_SIZE;
+
+  if (models.length === 0) {
+    return [[{ text: "<< Back", callback_data: "mdl_back" }]];
+  }
+
+  const rows: ButtonRow[] = [];
+
+  // Calculate page slice
+  const startIndex = (currentPage - 1) * pageSize;
+  const endIndex = Math.min(startIndex + pageSize, models.length);
+  const pageModels = models.slice(startIndex, endIndex);
+
+  // Model buttons - one per row
+  const currentModelId = currentModel?.includes("/")
+    ? currentModel.split("/").slice(1).join("/")
+    : currentModel;
+
+  for (const model of pageModels) {
+    const isCurrentModel = model === currentModelId;
+    const displayText = truncateModelId(model, 38);
+    const text = isCurrentModel ? `${displayText} ✓` : displayText;
+
+    rows.push([
+      {
+        text,
+        callback_data: `mdl_sel_${provider}/${model}`,
+      },
+    ]);
+  }
+
+  // Pagination row
+  if (totalPages > 1) {
+    const paginationRow: ButtonRow = [];
+
+    if (currentPage > 1) {
+      paginationRow.push({
+        text: "◀ Prev",
+        callback_data: `mdl_list_${provider}_${currentPage - 1}`,
+      });
+    }
+
+    paginationRow.push({
+      text: `${currentPage}/${totalPages}`,
+      callback_data: `mdl_list_${provider}_${currentPage}`, // noop
+    });
+
+    if (currentPage < totalPages) {
+      paginationRow.push({
+        text: "Next ▶",
+        callback_data: `mdl_list_${provider}_${currentPage + 1}`,
+      });
+    }
+
+    rows.push(paginationRow);
+  }
+
+  // Back button
+  rows.push([{ text: "<< Back", callback_data: "mdl_back" }]);
+
+  return rows;
+}
+
+/**
+ * Build "Browse providers" button for /model summary.
+ */
+export function buildBrowseProvidersButton(): ButtonRow[] {
+  return [[{ text: "Browse providers", callback_data: "mdl_prov" }]];
+}
+
+/**
+ * Truncate model ID for display, preserving end if too long.
+ */
+function truncateModelId(modelId: string, maxLen: number): string {
+  if (modelId.length <= maxLen) {
+    return modelId;
+  }
+  // Show last part with ellipsis prefix
+  return `…${modelId.slice(-(maxLen - 1))}`;
+}
+
+/**
+ * Get page size for model list pagination.
+ */
+export function getModelsPageSize(): number {
+  return MODELS_PAGE_SIZE;
+}
+
+/**
+ * Calculate total pages for a model list.
+ */
+export function calculateTotalPages(totalModels: number, pageSize?: number): number {
+  const size = pageSize ?? MODELS_PAGE_SIZE;
+  return size > 0 ? Math.ceil(totalModels / size) : 1;
+}