InkNote/frontend/src/export/markdown.test.ts

import { describe, it, expect } from "vitest";

import { noteToMarkdown, safeFilename } from "./markdown";
import type { DocNode } from "../editor/content";

const doc = (...content: DocNode[]): DocNode => ({ type: "doc", content });
const para = (...content: DocNode[]): DocNode => ({ type: "paragraph", content });
const text = (t: string, marks?: { type: string; attrs?: Record<string, unknown> }[]): DocNode =>
  ({ type: "text", text: t, ...(marks ? { marks } : {}) }) as DocNode;
const md = (d: DocNode, o = {}) => noteToMarkdown(d, o);

describe("text and marks", () => {
  it("writes a plain paragraph", () => {
    expect(md(doc(para(text("Hallo Welt"))))).toBe("Hallo Welt");
  });

  it("renders bold, italic and strikethrough", () => {
    expect(md(doc(para(text("fett", [{ type: "bold" }]))))).toBe("**fett**");
    expect(md(doc(para(text("kursiv", [{ type: "italic" }]))))).toBe("*kursiv*");
    expect(md(doc(para(text("weg", [{ type: "strike" }]))))).toBe("~~weg~~");
  });

  it("falls back to HTML for underline, which Markdown lacks", () => {
    expect(md(doc(para(text("unter", [{ type: "underline" }]))))).toBe("<u>unter</u>");
  });

  it("keeps a web link", () => {
    const out = md(doc(para(text("hier", [{ type: "link", attrs: { href: "https://example.com" } }]))));
    expect(out).toBe("[hier](https://example.com)");
  });

  it("escapes characters that would otherwise become syntax mid-line", () => {
    expect(md(doc(para(text("2 * 3 _und_ [mehr]"))))).toBe("2 \\* 3 \\_und\\_ \\[mehr\\]");
  });

  it("leaves ordinary punctuation alone, so the result stays readable", () => {
    expect(md(doc(para(text("Hallo. Alles gut! Preis: 5-10 EUR (ca.)"))))).toBe(
      "Hallo. Alles gut! Preis: 5-10 EUR (ca.)"
    );
  });

  it("escapes a leading marker so a paragraph does not become a list", () => {
    expect(md(doc(para(text("- kein Listenpunkt"))))).toBe("\\- kein Listenpunkt");
    expect(md(doc(para(text("1. kein Punkt"))))).toBe("\\1. kein Punkt");
    expect(md(doc(para(text("# keine Ueberschrift"))))).toBe("\\# keine Ueberschrift");
  });

  it("does not escape inside a code span, where backslashes are literal", () => {
    expect(md(doc(para(text("a_b", [{ type: "code" }]))))).toBe("`a_b`");
  });

  it("turns a hard break into a Markdown line break", () => {
    expect(md(doc(para(text("eins"), { type: "hardBreak" }, text("zwei"))))).toBe("eins  \nzwei");
  });
});

describe("blocks", () => {
  it("writes headings at their level", () => {
    expect(md(doc({ type: "heading", attrs: { level: 2 }, content: [text("Titel")] }))).toBe("## Titel");
  });

  it("clamps an out-of-range heading level instead of emitting nonsense", () => {
    expect(md(doc({ type: "heading", attrs: { level: 99 }, content: [text("X")] }))).toBe("###### X");
  });

  it("writes a bullet list", () => {
    const list = {
      type: "bulletList",
      content: [
        { type: "listItem", content: [para(text("eins"))] },
        { type: "listItem", content: [para(text("zwei"))] },
      ],
    };
    expect(md(doc(list))).toBe("- eins\n- zwei");
  });

  it("numbers an ordered list from its start attribute", () => {
    const list = {
      type: "orderedList",
      attrs: { start: 3 },
      content: [
        { type: "listItem", content: [para(text("drei"))] },
        { type: "listItem", content: [para(text("vier"))] },
      ],
    };
    expect(md(doc(list))).toBe("3. drei\n4. vier");
  });

  it("writes task state as a checkbox, so it survives the trip", () => {
    const list = {
      type: "taskList",
      content: [
        { type: "taskItem", attrs: { checked: true }, content: [para(text("erledigt"))] },
        { type: "taskItem", attrs: { checked: false }, content: [para(text("offen"))] },
      ],
    };
    expect(md(doc(list))).toBe("- [x] erledigt\n- [ ] offen");
  });

  it("writes a quote with every line prefixed", () => {
    const quote = { type: "blockquote", content: [para(text("zitiert"))] };
    expect(md(doc(quote))).toBe("> zitiert");
  });

  it("divides the blocks inside a quote, so a list does not swallow what follows", () => {
    const quote = {
      type: "blockquote",
      content: [
        { type: "heading", attrs: { level: 3 }, content: [text("Quartalszahlen")] },
        {
          type: "bulletList",
          content: [
            { type: "listItem", content: [para(text("Umsatz"))] },
            { type: "listItem", content: [para(text("Gewinn"))] },
          ],
        },
        para(text("Alles nach Plan.")),
      ],
    } as DocNode;
    // The dividing line is quoted as well: an empty line would end the quote.
    expect(md(doc(quote))).toBe(
      "> ### Quartalszahlen\n>\n> - Umsatz\n> - Gewinn\n>\n> Alles nach Plan."
    );
  });

  it("quotes a quote inside a quote", () => {
    const inner = { type: "blockquote", content: [para(text("innen"))] } as DocNode;
    const outer = { type: "blockquote", content: [para(text("außen")), inner] } as DocNode;
    expect(md(doc(outer))).toBe("> außen\n>\n> > innen");
  });

  it("fences a code block and keeps its language", () => {
    const code = { type: "codeBlock", attrs: { language: "js" }, content: [text("const a = 1;")] };
    expect(md(doc(code))).toBe("```js\nconst a = 1;\n```");
  });

  it("writes a horizontal rule", () => {
    expect(md(doc({ type: "horizontalRule" }))).toBe("---");
  });
});

describe("tables", () => {
  const cell = (t: string, type = "tableCell"): DocNode => ({ type, content: [para(text(t))] });

  it("writes a header row and separator", () => {
    const table = {
      type: "table",
      content: [
        { type: "tableRow", content: [cell("A", "tableHeader"), cell("B", "tableHeader")] },
        { type: "tableRow", content: [cell("1"), cell("2")] },
      ],
    };
    expect(md(doc(table))).toBe("| A | B |\n| --- | --- |\n| 1 | 2 |");
  });

  it("gives a headerless table an empty header, since Markdown has no other form", () => {
    const table = {
      type: "table",
      content: [{ type: "tableRow", content: [cell("1"), cell("2")] }],
    };
    const out = md(doc(table)).split("\n");
    expect(out[1]).toBe("| --- | --- |");
    expect(out[2]).toBe("| 1 | 2 |");
  });

  it("escapes a pipe inside a cell so the table does not break apart", () => {
    const table = {
      type: "table",
      content: [{ type: "tableRow", content: [cell("a|b", "tableHeader")] }],
    };
    expect(md(doc(table))).toContain("a\\|b");
    expect(md(doc(table))).not.toContain("a\\\\|b");
  });

  it("pads a short row so the columns stay aligned", () => {
    const table = {
      type: "table",
      content: [
        { type: "tableRow", content: [cell("A", "tableHeader"), cell("B", "tableHeader")] },
        { type: "tableRow", content: [cell("1")] },
      ],
    };
    expect(md(doc(table))).toContain("| 1 |  |");
  });
});

describe("images and note links", () => {
  it("points an attachment at its file in the archive", () => {
    const img = { type: "image", attrs: { attachmentId: "abc", alt: "Bild" } };
    const out = md(doc(img), { attachmentPath: (id: string) => `images/${id}.png` });
    expect(out).toBe("![Bild](images/abc.png)");
  });

  it("links to another exported note", () => {
    const link = para({ type: "noteLink", attrs: { noteId: "n1", label: "Andere Notiz" } });
    const out = md(doc(link), { notePath: (id: string) => `${id}.md` });
    expect(out).toBe("[Andere Notiz](n1.md)");
  });

  it("degrades a link to a note that was not exported, rather than leaving a dead file link", () => {
    const link = para({ type: "noteLink", attrs: { noteId: "n1", label: "Andere Notiz" } });
    expect(md(doc(link), { notePath: () => null })).toBe("Andere Notiz");
  });
});

describe("document framing", () => {
  it("puts the title in a heading", () => {
    expect(md(doc(para(text("Text"))), { title: "Meine Notiz" })).toBe("# Meine Notiz\n\nText");
  });

  it("says when a drawing could not come along, instead of dropping it silently", () => {
    const out = md(doc(para(text("Text"))), { hasDrawing: true });
    expect(out).toContain("drawing");
  });

  it("collapses the blank lines the block rules emit generously", () => {
    const out = md(doc(para(text("a")), para(), para(), para(text("b"))));
    expect(out).not.toMatch(/\n{3,}/);
  });

  it("survives an empty document", () => {
    expect(md(doc())).toBe("");
    expect(md({ type: "doc" })).toBe("");
  });

  it("keeps the children of a node type it does not know", () => {
    const weird = { type: "somethingNew", content: [para(text("trotzdem da"))] };
    expect(md(doc(weird))).toBe("trotzdem da");
  });
});

describe("safeFilename", () => {
  it("strips characters a filesystem would refuse", () => {
    expect(safeFilename('a/b\\c:d*e?f"g<h>i|j')).toBe("a-b-c-d-e-f-g-h-i-j");
  });

  it("falls back when nothing usable is left", () => {
    expect(safeFilename("")).toBe("Note");
    expect(safeFilename("///")).toBe("---");
  });

  it("caps the length", () => {
    expect(safeFilename("x".repeat(200)).length).toBe(80);
  });
});