feat: unified, editable frontmatter editor in publish modal

- Preset fields (from settings) are now seeded as editable/deletable rows in
  the modal alongside custom ones, using one consistent row style.
- The note's own merged frontmatter is shown as read-only (disabled) rows at
  the top of the list (only when 'Merge document frontmatter' is on, and only
  for keys not overridden by an editable row).
- Drops the separate read-only 'resolved' text preview; the rows are the
  WYSIWYG result.

Adds pure, unit-tested composeFrontmatter()/docFrontmatterToPairs() and removes
the superseded resolveFrontmatter(). Editable rows are authoritative: on a key
collision they override the merged document field. Presets are deep-copied so
editing rows never mutates saved settings.

Co-Authored-By: Claude

src/PublishModal.ts

@@ -1,5 +1,5 @@
 import { App, Modal, Setting } from "obsidian";
-import { Pair, parseNote, resolveFrontmatter } from "./frontmatter";
+import { Pair, composeFrontmatter, docFrontmatterToPairs, parseNote } from "./frontmatter";
 import { Strategy } from "./images";
 import { JekyllPublishSettings } from "./settings";
 import { deriveDate, deriveSlug } from "./slug";
@@ -15,18 +15,26 @@ export interface ModalResult {
 export class PublishModal extends Modal {
   private result: ModalResult;
   private mergeDoc = true;
-  private custom: Pair[] = [];
+  /** Editable rows = preset fields (seeded from settings) + custom additions. */
+  private editableRows: Pair[];
+  /** The note's own frontmatter, shown read-only when merge is on. */
+  private readonly docPairs: Pair[];
+  private fmEl!: HTMLElement;
 
   constructor(
     app: App,
-    private settings: JekyllPublishSettings,
+    settings: JekyllPublishSettings,
     private noteText: string,
-    private filename: string,
+    filename: string,
     private onSubmit: (r: ModalResult) => void
   ) {
     super(app);
     const { frontmatter } = parseNote(noteText);
     const title = typeof frontmatter.title === "string" ? frontmatter.title : "";
+    this.docPairs = docFrontmatterToPairs(frontmatter);
+    // Deep-copy the presets so editing/deleting rows here never mutates the
+    // saved settings.
+    this.editableRows = settings.presetFrontmatter.map((p) => ({ key: p.key, value: p.value }));
     this.result = {
       frontmatterPairs: [],
       slug: deriveSlug({ title, filename }),
@@ -37,13 +45,7 @@ export class PublishModal extends Modal {
   }
 
   private recompute() {
-    const { frontmatter } = parseNote(this.noteText);
-    this.result.frontmatterPairs = resolveFrontmatter(
-      this.settings.presetFrontmatter,
-      frontmatter,
-      this.custom,
-      this.mergeDoc
-    );
+    this.result.frontmatterPairs = composeFrontmatter(this.docPairs, this.editableRows, this.mergeDoc);
   }
 
   onOpen() {
@@ -63,16 +65,23 @@ export class PublishModal extends Modal {
         .setValue(this.result.strategy)
         .onChange((v) => (this.result.strategy = v as Strategy))
     );
-    new Setting(contentEl).setName("Merge document frontmatter").addToggle((t) =>
-      t.setValue(this.mergeDoc).onChange((v) => { this.mergeDoc = v; this.renderFrontmatter(); })
-    );
+    new Setting(contentEl)
+      .setName("Merge document frontmatter")
+      .setDesc("Include the note's own frontmatter (shown read-only below).")
+      .addToggle((t) =>
+        t.setValue(this.mergeDoc).onChange((v) => {
+          this.mergeDoc = v;
+          this.renderFrontmatter();
+        })
+      );
 
+    contentEl.createEl("h3", { text: "Frontmatter" });
     this.fmEl = contentEl.createDiv();
     this.renderFrontmatter();
 
     new Setting(contentEl).addButton((b) =>
       b.setButtonText("Add property").onClick(() => {
-        this.custom.push({ key: "", value: "" });
+        this.editableRows = [...this.editableRows, { key: "", value: "" }];
         this.renderFrontmatter();
       })
     );
@@ -88,25 +97,52 @@ export class PublishModal extends Modal {
     );
   }
 
-  private fmEl!: HTMLElement;
   private renderFrontmatter() {
     this.recompute();
     this.fmEl.empty();
-    this.fmEl.createEl("h3", { text: "Frontmatter (resolved)" });
-    for (const p of this.result.frontmatterPairs) {
-      this.fmEl.createDiv({ cls: "jekyll-publish-row", text: `${p.key}: ${p.value}` });
-    }
-    if (this.custom.length) {
-      this.fmEl.createEl("h4", { text: "Custom properties" });
-      this.custom.forEach((row, i) => {
-        const div = this.fmEl.createDiv({ cls: "jekyll-publish-row" });
-        const k = div.createEl("input", { value: row.key, placeholder: "key" });
-        const v = div.createEl("input", { value: row.value, placeholder: "value" });
-        k.oninput = () => { this.custom[i].key = k.value; this.recompute(); };
-        v.oninput = () => { this.custom[i].value = v.value; this.recompute(); };
-      });
+
+    const editableKeys = new Set(
+      this.editableRows.filter((r) => r.key.trim() !== "").map((r) => r.key)
+    );
+
+    // Document fields (read-only) first — only those not overridden by an
+    // editable row, so the modal never shows a key twice.
+    if (this.mergeDoc) {
+      const docRows = this.docPairs.filter((p) => !editableKeys.has(p.key));
+      for (const p of docRows) {
+        const row = this.fmEl.createDiv({ cls: "jekyll-publish-row" });
+        const k = row.createEl("input", { cls: "jekyll-publish-doc", value: p.key });
+        const v = row.createEl("input", { cls: "jekyll-publish-doc", value: p.value });
+        k.disabled = true;
+        v.disabled = true;
+        k.title = "From the note's frontmatter (edit the note to change)";
+        v.title = k.title;
+      }
     }
+
+    // Editable rows (presets + custom) — same style, all editable and deletable.
+    this.editableRows.forEach((row, i) => {
+      const div = this.fmEl.createDiv({ cls: "jekyll-publish-row" });
+      const k = div.createEl("input", { value: row.key, placeholder: "key" });
+      const v = div.createEl("input", { value: row.value, placeholder: "value" });
+      k.oninput = () => {
+        this.editableRows = this.editableRows.map((r, j) => (j === i ? { ...r, key: k.value } : r));
+        this.recompute();
+      };
+      v.oninput = () => {
+        this.editableRows = this.editableRows.map((r, j) => (j === i ? { ...r, value: v.value } : r));
+        this.recompute();
+      };
+      const del = div.createEl("button", { cls: "jekyll-publish-del", text: "×" });
+      del.setAttr("aria-label", "Delete property");
+      del.onclick = () => {
+        this.editableRows = this.editableRows.filter((_, j) => j !== i);
+        this.renderFrontmatter();
+      };
+    });
   }
 
-  onClose() { this.contentEl.empty(); }
+  onClose() {
+    this.contentEl.empty();
+  }
 }

src/frontmatter.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, test } from "vitest";
-import { parseNote, resolveFrontmatter, serializeFrontmatter } from "./frontmatter";
+import { composeFrontmatter, docFrontmatterToPairs, parseNote, serializeFrontmatter } from "./frontmatter";
 
 describe("parseNote", () => {
   test("splits frontmatter and body, strips BOM", () => {
@@ -12,27 +12,70 @@ describe("parseNote", () => {
   });
 });
 
-describe("resolveFrontmatter", () => {
-  const presets = [{ key: "layout", value: "post" }, { key: "kind", value: "essay" }];
-  test("presets only when mergeDoc is false", () => {
-    expect(resolveFrontmatter(presets, { title: "X" }, [], false)).toEqual(presets);
-  });
-  test("merge appends doc keys and doc overrides preset value", () => {
-    const r = resolveFrontmatter(presets, { kind: "note", title: "X" }, [], true);
-    expect(r).toEqual([
-      { key: "layout", value: "post" },
-      { key: "kind", value: "note" },
-      { key: "title", value: "X" },
+describe("docFrontmatterToPairs", () => {
+  test("converts a record to ordered string pairs", () => {
+    const pairs = docFrontmatterToPairs({
+      title: "Hello",
+      date: new Date("2026-02-06T00:00:00Z"),
+      draft: true,
+    });
+    expect(pairs).toEqual([
+      { key: "title", value: "Hello" },
+      { key: "date", value: "2026-02-06" },
+      { key: "draft", value: "true" },
     ]);
   });
-  test("custom rows come last and override everything", () => {
-    const r = resolveFrontmatter(presets, {}, [{ key: "layout", value: "page" }], false);
-    expect(r[0]).toEqual({ key: "layout", value: "page" });
-    expect(r).toHaveLength(2);
+  test("empty record yields an empty array", () => {
+    expect(docFrontmatterToPairs({})).toEqual([]);
   });
-  test("date object is rendered as YYYY-MM-DD", () => {
-    const r = resolveFrontmatter([], { date: new Date("2026-06-11T00:00:00Z") }, [], true);
-    expect(r).toEqual([{ key: "date", value: "2026-06-11" }]);
+});
+
+describe("composeFrontmatter", () => {
+  const doc = [
+    { key: "title", value: "Hello" },
+    { key: "date", value: "2026-02-06" },
+  ];
+  const editable = [
+    { key: "layout", value: "post" },
+    { key: "kind", value: "essay" },
+  ];
+
+  test("merge on: document fields first, then editable rows", () => {
+    expect(composeFrontmatter(doc, editable, true)).toEqual([
+      { key: "title", value: "Hello" },
+      { key: "date", value: "2026-02-06" },
+      { key: "layout", value: "post" },
+      { key: "kind", value: "essay" },
+    ]);
+  });
+  test("merge off: only the editable rows", () => {
+    expect(composeFrontmatter(doc, editable, false)).toEqual(editable);
+  });
+  test("an editable row overrides a document field with the same key (doc field dropped)", () => {
+    const ed = [
+      { key: "title", value: "Override" },
+      { key: "layout", value: "post" },
+    ];
+    expect(composeFrontmatter(doc, ed, true)).toEqual([
+      { key: "date", value: "2026-02-06" },
+      { key: "title", value: "Override" },
+      { key: "layout", value: "post" },
+    ]);
+  });
+  test("blank-key editable rows are skipped", () => {
+    const ed = [
+      { key: "", value: "" },
+      { key: "layout", value: "post" },
+      { key: "  ", value: "x" },
+    ];
+    expect(composeFrontmatter([], ed, true)).toEqual([{ key: "layout", value: "post" }]);
+  });
+  test("duplicate editable keys: last value wins at first position", () => {
+    const ed = [
+      { key: "tag", value: "a" },
+      { key: "tag", value: "b" },
+    ];
+    expect(composeFrontmatter([], ed, false)).toEqual([{ key: "tag", value: "b" }]);
   });
 });
 

src/frontmatter.ts

@@ -14,12 +14,26 @@ export function parseNote(text: string): { frontmatter: Record<string, unknown>;
   return { frontmatter, body: stripped.slice(m[0].length) };
 }
 
-export function resolveFrontmatter(
-  presets: Pair[],
-  docFrontmatter: Record<string, unknown>,
-  custom: Pair[],
-  mergeDoc: boolean
-): Pair[] {
+/**
+ * Convert a parsed note's frontmatter object into ordered, stringified pairs
+ * suitable for display (read-only) and composition.
+ */
+export function docFrontmatterToPairs(docFrontmatter: Record<string, unknown>): Pair[] {
+  return Object.entries(docFrontmatter).map(([key, v]) => ({ key, value: stringifyScalar(v) }));
+}
+
+/**
+ * Build the final frontmatter for the post.
+ *
+ * Editable rows (the preset fields seeded from settings plus any custom rows
+ * the user added) are authoritative: on a key collision they win over the
+ * document's own merged fields, which appear first (and are shown read-only in
+ * the modal). Blank-key rows are dropped; duplicate editable keys keep the last
+ * value at the first position.
+ */
+export function composeFrontmatter(docPairs: Pair[], editableRows: Pair[], mergeDoc: boolean): Pair[] {
+  const editable = editableRows.filter((r) => r.key.trim() !== "");
+  const editableKeys = new Set(editable.map((r) => r.key));
   const out: Pair[] = [];
   const idx = new Map<string, number>();
   const put = (key: string, value: string) => {
@@ -27,9 +41,8 @@ export function resolveFrontmatter(
     if (at !== undefined) out[at] = { key, value };
     else { idx.set(key, out.length); out.push({ key, value }); }
   };
-  for (const p of presets) put(p.key, p.value);
-  if (mergeDoc) for (const [k, v] of Object.entries(docFrontmatter)) put(k, stringifyScalar(v));
-  for (const c of custom) put(c.key, c.value);
+  if (mergeDoc) for (const p of docPairs) if (!editableKeys.has(p.key)) put(p.key, p.value);
+  for (const r of editable) put(r.key, r.value);
   return out;
 }
 

styles.css

@@ -1,2 +1,17 @@
-.jekyll-publish-row { display: flex; gap: 8px; margin-bottom: 6px; }
+.jekyll-publish-row { display: flex; gap: 8px; margin-bottom: 6px; align-items: center; }
 .jekyll-publish-row input { flex: 1; }
+
+/* Read-only document frontmatter fields shown when "Merge document
+   frontmatter" is on — visually muted to signal they cannot be edited here. */
+.jekyll-publish-row input.jekyll-publish-doc {
+  opacity: 0.65;
+  cursor: not-allowed;
+}
+
+/* Delete button on an editable property row. */
+.jekyll-publish-del {
+  flex: 0 0 auto;
+  width: 28px;
+  padding: 0;
+  line-height: 1;
+}