diff --git a/lib/editor/draft.test.ts b/lib/editor/draft.test.ts
new file mode 100644
index 0000000..98a76fb
--- /dev/null
+++ b/lib/editor/draft.test.ts
@@ -0,0 +1,40 @@
+import { describe, expect, it } from "vitest";
+
+import type { SerializedBlock } from "@/lib/blocks";
+
+import {
+  createEditorBlock,
+  duplicateBlock,
+  moveBlock,
+  moveBlockTo,
+} from "./draft";
+
+const blocks: SerializedBlock[] = ["a", "b", "c"].map((id, sortOrder) => ({
+  id,
+  type: "separator",
+  schemaVersion: 1,
+  config: {},
+  sortOrder,
+}));
+
+describe("editor block operations", () => {
+  it("moves blocks with keyboard-friendly relative operations", () => {
+    expect(moveBlock(blocks, "b", -1).map((block) => block.id)).toEqual(["b", "a", "c"]);
+    expect(moveBlock(blocks, "a", -1)).toEqual(blocks);
+    expect(moveBlock(blocks, "b", 1).map((block) => block.sortOrder)).toEqual([0, 1, 2]);
+  });
+
+  it("supports pointer drop targets and duplication with stable order", () => {
+    expect(moveBlockTo(blocks, "a", "c").map((block) => block.id)).toEqual(["b", "c", "a"]);
+    expect(duplicateBlock(blocks, "b", "copy").map((block) => block.id)).toEqual(["a", "b", "copy", "c"]);
+  });
+
+  it("requires a configured source for data-backed blocks", () => {
+    expect(createEditorBlock("comparison-chart")).toBeNull();
+    expect(createEditorBlock("heading", undefined, "heading-id")).toMatchObject({
+      id: "heading-id",
+      type: "heading",
+      config: { text: "หัวข้อใหม่" },
+    });
+  });
+});
diff --git a/lib/editor/draft.ts b/lib/editor/draft.ts
new file mode 100644
index 0000000..7265788
--- /dev/null
+++ b/lib/editor/draft.ts
@@ -0,0 +1,179 @@
+import type { SerializedBlock } from "@/lib/blocks";
+import type { DataSourceSnapshot, PageSnapshot } from "@/lib/content/types";
+
+export interface EditorDraft {
+  pageId: string;
+  title: string;
+  slug: string;
+  visible: boolean;
+  publicNote: string | null;
+  blocks: SerializedBlock[];
+}
+
+export function draftFromSnapshot(snapshot: PageSnapshot): EditorDraft {
+  return {
+    pageId: snapshot.page.id,
+    title: snapshot.page.title,
+    slug: snapshot.page.slug,
+    visible: snapshot.page.visible,
+    publicNote: snapshot.page.publicNote,
+    blocks: structuredClone(snapshot.blocks),
+  };
+}
+
+export function normalizeBlockOrder(
+  blocks: readonly SerializedBlock[],
+): SerializedBlock[] {
+  return blocks.map((block, sortOrder) => ({ ...block, sortOrder }));
+}
+
+export function moveBlock(
+  blocks: readonly SerializedBlock[],
+  blockId: string,
+  direction: -1 | 1,
+): SerializedBlock[] {
+  const current = blocks.findIndex((block) => block.id === blockId);
+  const target = current + direction;
+  if (current < 0 || target < 0 || target >= blocks.length) return [...blocks];
+  const next = [...blocks];
+  [next[current], next[target]] = [next[target], next[current]];
+  return normalizeBlockOrder(next);
+}
+
+export function moveBlockTo(
+  blocks: readonly SerializedBlock[],
+  blockId: string,
+  targetId: string,
+): SerializedBlock[] {
+  const from = blocks.findIndex((block) => block.id === blockId);
+  const target = blocks.findIndex((block) => block.id === targetId);
+  if (from < 0 || target < 0 || from === target) return [...blocks];
+  const next = [...blocks];
+  const [moved] = next.splice(from, 1);
+  next.splice(target, 0, moved);
+  return normalizeBlockOrder(next);
+}
+
+export function duplicateBlock(
+  blocks: readonly SerializedBlock[],
+  blockId: string,
+  id = crypto.randomUUID(),
+): SerializedBlock[] {
+  const index = blocks.findIndex((block) => block.id === blockId);
+  if (index < 0) return [...blocks];
+  const clone = structuredClone(blocks[index]);
+  clone.id = id;
+  const next = [...blocks];
+  next.splice(index + 1, 0, clone);
+  return normalizeBlockOrder(next);
+}
+
+function sourceFields(source: DataSourceSnapshot | undefined) {
+  const text = source?.fields.find((field) => field.type !== "number")?.key ?? "name";
+  const numbers = source?.fields.filter((field) => field.type === "number" || field.formula) ?? [];
+  return { text, numbers };
+}
+
+export function createEditorBlock(
+  type: string,
+  source?: DataSourceSnapshot,
+  id = crypto.randomUUID(),
+): SerializedBlock | null {
+  const nestedId = () => crypto.randomUUID();
+  const { text, numbers } = sourceFields(source);
+  const numeric = numbers[0]?.key ?? "value";
+  const configs: Record<string, Record<string, unknown> | null> = {
+    profile: { title: "หัวข้อโปรไฟล์", summary: "เพิ่มคำแนะนำสั้น ๆ", badges: [] },
+    "rich-text": { content: [{ type: "paragraph", text: "เริ่มเขียนเนื้อหาที่นี่" }] },
+    heading: { text: "หัวข้อใหม่", level: 2 },
+    callout: { title: "ข้อควรรู้", body: "เพิ่มรายละเอียด", tone: "info" },
+    "stat-cards": {
+      title: "ค่าสำคัญ",
+      items: [{ id: nestedId(), label: "ค่า", value: "—" }],
+    },
+    "key-value": {
+      items: [{ id: nestedId(), label: "หัวข้อ", value: "รายละเอียด" }],
+      columns: 2,
+    },
+    ranking: source
+      ? {
+          title: "อันดับ",
+          dataSourceId: source.id,
+          labelField: text,
+          valueField: numeric,
+          higherIsBetter: true,
+        }
+      : null,
+    "team-composition": source
+      ? {
+          title: "ทีมแนะนำ",
+          dataSourceId: source.id,
+          teamField: text,
+          memberFields: [text],
+        }
+      : null,
+    rotation: {
+      title: "ลำดับการเล่น",
+      steps: [{ id: nestedId(), action: "เพิ่มขั้นตอน" }],
+    },
+    table: source
+      ? {
+          dataSourceId: source.id,
+          columns: source.fields.slice(0, 4).map((field) => ({
+            field: field.key,
+            label: field.label,
+            align: field.type === "number" ? "end" : "start",
+          })),
+        }
+      : null,
+    "comparison-chart": source && numbers.length > 0
+      ? {
+          title: "กราฟเปรียบเทียบ",
+          dataSourceId: source.id,
+          categoryField: text,
+          series: [{ field: numeric, label: numbers[0].label, color: "chart-1" }],
+          presentation: "horizontal-bar",
+          normalization: "raw",
+          sort: "authored",
+          showValues: true,
+          showLegend: false,
+          tableFallback: true,
+        }
+      : null,
+    image: null,
+    gallery: null,
+    tabs: {
+      tabs: [
+        { id: nestedId(), label: "ตัวเลือก 1", content: "เพิ่มรายละเอียด" },
+        { id: nestedId(), label: "ตัวเลือก 2", content: "เพิ่มรายละเอียด" },
+      ],
+    },
+    accordion: {
+      items: [{ id: nestedId(), title: "หัวข้อ", content: "เพิ่มรายละเอียด" }],
+    },
+    section: { title: "ส่วนใหม่" },
+    columns: { columns: 2, gap: "normal" },
+    links: {
+      links: [{ id: nestedId(), label: "ลิงก์", href: "/", description: "เพิ่มคำอธิบาย" }],
+    },
+    separator: {},
+  };
+  const config = configs[type];
+  if (!config) return null;
+  return {
+    id,
+    type,
+    schemaVersion: 1,
+    config,
+    responsiveLayout: {
+      width: ["ranking", "table", "comparison-chart", "team-composition", "gallery"].includes(type)
+        ? "wide"
+        : "content",
+      mobileSpan: 4,
+      tabletSpan: 8,
+      desktopSpan: 12,
+      hideOnMobile: false,
+    },
+    sortOrder: 0,
+  };
+}