4 files changed, 919 insertions, 0 deletions
diff --git a/docs/README.md b/docs/README.md
new file mode 100644
index 0000000..f115e96
--- /dev/null
+++ b/docs/README.md
@@ -0,0 +1,2 @@
+## GENERATED CODE
+Yes, this is non hand artisanally crafted code, it may be a bit nuts
diff --git a/docs/package.json b/docs/package.json
new file mode 100644
index 0000000..cfcc1a9
--- /dev/null
+++ b/docs/package.json
@@ -0,0 +1,9 @@
+{
+  "name": "99-docs",
+  "private": true,
+  "type": "module",
+  "scripts": {
+    "generate": "node --experimental-strip-types src/generate.ts",
+    "check": "node --experimental-strip-types src/generate.ts --check"
+  }
+}
diff --git a/docs/src/generate.ts b/docs/src/generate.ts
new file mode 100644
index 0000000..e25b5ad
--- /dev/null
+++ b/docs/src/generate.ts
@@ -0,0 +1,896 @@
+import { promises as fs } from "node:fs";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+
+type DocsTag = "base" | "include";
+
+type FieldDoc = {
+  name: string;
+  type: string;
+  line: number;
+  descriptionLines: string[];
+  defaultValue?: string;
+};
+
+type ClassDoc = {
+  name: string;
+  extendsType?: string;
+  line: number;
+  filePath: string;
+  tags: Set<DocsTag>;
+  descriptionLines: string[];
+  fields: FieldDoc[];
+  references: string[];
+};
+
+const COMMENT_LINE = /^\s*---\s?(.*)$/;
+
+async function main(): Promise<void> {
+  const checkMode = process.argv.includes("--check");
+  const stdoutMode = process.argv.includes("--stdout");
+
+  const scriptDir = path.dirname(fileURLToPath(import.meta.url));
+  const docsRoot = path.resolve(scriptDir, "..");
+  const repoRoot = path.resolve(docsRoot, "..");
+  const luaRoot = path.join(repoRoot, "lua", "99");
+  const readmePath = path.join(docsRoot, "README.md");
+
+  const luaFiles = await collectLuaFiles(luaRoot);
+  const parsedClasses = await parseClassesFromFiles(luaFiles, repoRoot);
+  const classesByName = dedupeClasses(parsedClasses);
+
+  attachReferences(classesByName);
+
+  const rootNames = [...classesByName.values()]
+    .filter((cls) => cls.tags.has("base"))
+    .map((cls) => cls.name)
+    .sort((a, b) => a.localeCompare(b));
+
+  const reachableNames = resolveReachableTypes(rootNames, classesByName);
+  const documentedNames = reachableNames.filter((name) => {
+    const cls = classesByName.get(name);
+    return Boolean(cls && (cls.tags.has("base") || cls.tags.has("include")));
+  });
+
+  const markdown = renderMarkdown(documentedNames, classesByName);
+
+  if (stdoutMode) {
+    process.stdout.write(markdown);
+    return;
+  }
+
+  if (checkMode) {
+    const existing = await readFileIfExists(readmePath);
+    if (existing !== markdown) {
+      console.error("[docs] README.md is out of date. Run: ./gen-docs");
+      process.exitCode = 1;
+      return;
+    }
+
+    console.log("[docs] README.md is up to date");
+    return;
+  }
+
+  await fs.writeFile(readmePath, markdown, "utf8");
+  console.log(`[docs] wrote ${path.relative(repoRoot, readmePath)}`);
+}
+
+function renderMarkdown(
+  documentedNames: string[],
+  classesByName: Map<string, ClassDoc>,
+): string {
+  const lines: string[] = [];
+
+  lines.push("# 99");
+  lines.push("The AI Neovim experience");
+
+  if (documentedNames.length === 0) {
+    lines.push("");
+    lines.push("No documented types found.");
+    return `${lines.join("\n")}\n`;
+  }
+
+  for (const name of documentedNames) {
+    const cls = classesByName.get(name);
+    if (!cls) {
+      continue;
+    }
+
+    lines.push("");
+    lines.push(`## ${cls.name}`);
+
+    const classDescription = renderDescription(cls.descriptionLines);
+    if (classDescription.length > 0) {
+      lines.push(...classDescription);
+    } else {
+      lines.push("No description.");
+    }
+
+    lines.push("");
+    lines.push("### Description");
+    lines.push("| Name | Type | Default Value |");
+    lines.push("| --- | --- | --- |");
+
+    if (cls.fields.length === 0) {
+      lines.push("| - | - | - |");
+    } else {
+      for (const field of cls.fields) {
+        lines.push(
+          `| \`${escapeTableCell(field.name)}\` | \`${escapeTableCell(field.type)}\` | ${escapeTableCell(field.defaultValue ?? "-")} |`,
+        );
+      }
+    }
+
+    lines.push("");
+    lines.push("### API");
+
+    if (cls.fields.length === 0) {
+      lines.push("No properties.");
+    } else {
+      for (const field of cls.fields) {
+        lines.push("");
+        lines.push(`#### ${field.name}`);
+
+        const fieldDescription = renderDescription(field.descriptionLines);
+        if (fieldDescription.length > 0) {
+          lines.push(...fieldDescription);
+        } else {
+          lines.push("No description.");
+        }
+
+        if (field.defaultValue) {
+          lines.push("");
+          lines.push(`**default**: ${field.defaultValue}`);
+        }
+      }
+    }
+  }
+
+  return `${lines.join("\n")}\n`;
+}
+
+function renderDescription(rawLines: string[]): string[] {
+  const trimmed = trimEdgeBlankLines(rawLines);
+  return trimmed;
+}
+
+function trimEdgeBlankLines(lines: string[]): string[] {
+  let start = 0;
+  let end = lines.length;
+
+  while (start < end && lines[start]?.trim().length === 0) {
+    start += 1;
+  }
+
+  while (end > start && lines[end - 1]?.trim().length === 0) {
+    end -= 1;
+  }
+
+  return lines.slice(start, end);
+}
+
+function escapeTableCell(value: string): string {
+  const normalized = normalizeWhitespace(value);
+  if (normalized.length === 0) {
+    return "-";
+  }
+
+  return normalized.replace(/\|/g, "\\|");
+}
+
+function resolveReachableTypes(
+  roots: string[],
+  classesByName: Map<string, ClassDoc>,
+): string[] {
+  const visited = new Set<string>();
+  const queue = [...roots];
+  const order: string[] = [];
+
+  while (queue.length > 0) {
+    const name = queue.shift();
+    if (!name || visited.has(name)) {
+      continue;
+    }
+
+    const cls = classesByName.get(name);
+    if (!cls) {
+      continue;
+    }
+
+    visited.add(name);
+    order.push(name);
+
+    for (const ref of cls.references) {
+      if (!visited.has(ref)) {
+        queue.push(ref);
+      }
+    }
+  }
+
+  return order;
+}
+
+function attachReferences(classesByName: Map<string, ClassDoc>): void {
+  const names = new Set(classesByName.keys());
+
+  for (const cls of classesByName.values()) {
+    const refs = new Set<string>();
+
+    if (cls.extendsType) {
+      for (const token of extractTypeTokens(cls.extendsType)) {
+        if (token !== cls.name && names.has(token)) {
+          refs.add(token);
+        }
+      }
+    }
+
+    for (const field of cls.fields) {
+      for (const token of extractTypeTokens(field.type)) {
+        if (token !== cls.name && names.has(token)) {
+          refs.add(token);
+        }
+      }
+    }
+
+    cls.references = [...refs].sort((a, b) => a.localeCompare(b));
+  }
+}
+
+function extractTypeTokens(typeExpression: string): string[] {
+  const withoutStrings = typeExpression.replace(
+    /"(?:\\.|[^"\\])*"|'(?:\\.|[^'\\])*'/g,
+    " ",
+  );
+
+  const matches = withoutStrings.match(/[A-Za-z_][A-Za-z0-9_.]*/g);
+  return matches ?? [];
+}
+
+function dedupeClasses(parsed: ClassDoc[]): Map<string, ClassDoc> {
+  const sorted = [...parsed].sort((a, b) => {
+    const byName = a.name.localeCompare(b.name);
+    if (byName !== 0) {
+      return byName;
+    }
+
+    const byPath = a.filePath.localeCompare(b.filePath);
+    if (byPath !== 0) {
+      return byPath;
+    }
+
+    return a.line - b.line;
+  });
+
+  const classesByName = new Map<string, ClassDoc>();
+
+  for (const cls of sorted) {
+    const existing = classesByName.get(cls.name);
+    if (!existing) {
+      classesByName.set(cls.name, cls);
+      continue;
+    }
+
+    classesByName.set(cls.name, pickPreferredClass(existing, cls));
+  }
+
+  return classesByName;
+}
+
+function pickPreferredClass(a: ClassDoc, b: ClassDoc): ClassDoc {
+  const score = (cls: ClassDoc): number => {
+    const docsWeight = cls.tags.size > 0 ? 1000 : 0;
+    const testPenalty = cls.filePath.includes("/test/") ? -100 : 0;
+    return docsWeight + cls.fields.length + testPenalty;
+  };
+
+  return score(b) > score(a) ? b : a;
+}
+
+async function parseClassesFromFiles(
+  luaFiles: string[],
+  repoRoot: string,
+): Promise<ClassDoc[]> {
+  const classes: ClassDoc[] = [];
+
+  for (const file of luaFiles) {
+    const source = await fs.readFile(file, "utf8");
+    const relative = normalizePath(path.relative(repoRoot, file));
+    classes.push(...parseLuaDocClasses(source, relative));
+  }
+
+  return classes;
+}
+
+function parseLuaDocClasses(source: string, filePath: string): ClassDoc[] {
+  const lines = source.split(/\r?\n/);
+  const classes: ClassDoc[] = [];
+
+  let pendingTags = new Set<DocsTag>();
+  let currentClass: ClassDoc | undefined;
+  let currentField: FieldDoc | undefined;
+
+  const flushCurrentClass = (): void => {
+    if (!currentClass) {
+      return;
+    }
+
+    classes.push(currentClass);
+    currentClass = undefined;
+    currentField = undefined;
+  };
+
+  for (let i = 0; i < lines.length; i += 1) {
+    const commentMatch = lines[i]?.match(COMMENT_LINE);
+
+    if (!commentMatch) {
+      flushCurrentClass();
+      pendingTags = new Set<DocsTag>();
+      continue;
+    }
+
+    const text = commentMatch[1] ?? "";
+    const tagText = text.trim();
+
+    if (tagText.startsWith("@class ")) {
+      flushCurrentClass();
+
+      const parsedClass = parseClassSignature(tagText.slice("@class ".length));
+      if (!parsedClass) {
+        pendingTags = new Set<DocsTag>();
+        continue;
+      }
+
+      currentClass = {
+        name: parsedClass.name,
+        extendsType: parsedClass.extendsType,
+        line: i + 1,
+        filePath,
+        tags: pendingTags,
+        descriptionLines: parsedClass.description ? [parsedClass.description] : [],
+        fields: [],
+        references: [],
+      };
+      pendingTags = new Set<DocsTag>();
+      currentField = undefined;
+      continue;
+    }
+
+    const docsTag = parseDocsTag(tagText);
+    if (docsTag) {
+      if (currentClass) {
+        currentClass.tags.add(docsTag);
+      } else {
+        pendingTags.add(docsTag);
+      }
+      continue;
+    }
+
+    if (!currentClass) {
+      continue;
+    }
+
+    if (tagText.startsWith("@field ")) {
+      const field = parseFieldSignature(tagText.slice("@field ".length), i + 1);
+      if (field) {
+        currentClass.fields.push(field);
+        currentField = field;
+      }
+      continue;
+    }
+
+    if (tagText.startsWith("@")) {
+      flushCurrentClass();
+      pendingTags = new Set<DocsTag>();
+      continue;
+    }
+
+    if (text.trim().length === 0) {
+      if (currentField) {
+        currentField.descriptionLines.push("");
+      } else {
+        currentClass.descriptionLines.push("");
+      }
+      continue;
+    }
+
+    if (currentField) {
+      applyFieldDocLine(currentField, text);
+    } else {
+      currentClass.descriptionLines.push(text);
+    }
+  }
+
+  flushCurrentClass();
+  return classes;
+}
+
+function parseDocsTag(text: string): DocsTag | undefined {
+  if (!text.startsWith("@docs ")) {
+    return undefined;
+  }
+
+  const value = text
+    .slice("@docs ".length)
+    .trim()
+    .split(/\s+/)[0]
+    ?.toLowerCase();
+
+  if (value === "base") {
+    return "base";
+  }
+
+  if (value === "include" || value === "included") {
+    return "include";
+  }
+
+  return undefined;
+}
+
+function parseClassSignature(signature: string): {
+  name: string;
+  extendsType?: string;
+  description?: string;
+} | null {
+  const text = signature.trim();
+  if (text.length === 0) {
+    return null;
+  }
+
+  let cursor = 0;
+  while (cursor < text.length && !/[\s:]/.test(text[cursor]!)) {
+    cursor += 1;
+  }
+
+  const name = text.slice(0, cursor);
+  if (name.length === 0) {
+    return null;
+  }
+
+  let rest = text.slice(cursor).trim();
+  let extendsType: string | undefined;
+
+  if (rest.startsWith(":")) {
+    rest = rest.slice(1).trim();
+
+    let extendsCursor = 0;
+    while (extendsCursor < rest.length && !/\s/.test(rest[extendsCursor]!)) {
+      extendsCursor += 1;
+    }
+
+    extendsType = rest.slice(0, extendsCursor).trim();
+    rest = rest.slice(extendsCursor).trim();
+  }
+
+  return {
+    name,
+    extendsType,
+    description: rest.length > 0 ? rest : undefined,
+  };
+}
+
+function parseFieldSignature(signature: string, line: number): FieldDoc | null {
+  const text = signature.trim();
+  if (text.length === 0) {
+    return null;
+  }
+
+  const firstSpace = text.search(/\s/);
+  if (firstSpace < 0) {
+    const normalized = normalizeFieldOptionality(text, "unknown");
+    return {
+      name: normalized.name,
+      type: normalized.type,
+      line,
+      descriptionLines: [],
+    };
+  }
+
+  const rawName = text.slice(0, firstSpace).trim();
+  const remainder = text.slice(firstSpace + 1).trim();
+  const { type, description } = splitTypeAndDescription(remainder);
+  const normalized = normalizeFieldOptionality(rawName, type);
+
+  const field: FieldDoc = {
+    name: normalized.name,
+    type: normalized.type,
+    line,
+    descriptionLines: [],
+  };
+
+  if (description) {
+    applyFieldDocLine(field, description);
+  }
+
+  return field;
+}
+
+function normalizeFieldOptionality(
+  rawName: string,
+  rawType: string,
+): { name: string; type: string } {
+  const optional = rawName.endsWith("?");
+  const name = optional ? rawName.slice(0, -1) : rawName;
+  let type = normalizeWhitespace(rawType);
+
+  if (optional) {
+    type = ensureNilInType(type);
+  }
+
+  return { name, type };
+}
+
+function ensureNilInType(typeExpression: string): string {
+  if (/\bnil\b/.test(typeExpression)) {
+    return typeExpression;
+  }
+
+  return `${typeExpression} | nil`;
+}
+
+function splitTypeAndDescription(input: string): {
+  type: string;
+  description?: string;
+} {
+  const text = input.trim();
+  if (text.length === 0) {
+    return { type: "unknown" };
+  }
+
+  let i = 0;
+  let inQuote: '"' | "'" | null = null;
+  let angleDepth = 0;
+  let parenDepth = 0;
+  let braceDepth = 0;
+  let expectTypeAtom = true;
+
+  while (i < text.length) {
+    const ch = text[i]!;
+
+    if (inQuote) {
+      if (ch === "\\") {
+        i += 2;
+        continue;
+      }
+
+      if (ch === inQuote) {
+        inQuote = null;
+      }
+
+      i += 1;
+      continue;
+    }
+
+    if (ch === '"' || ch === "'") {
+      inQuote = ch;
+      expectTypeAtom = false;
+      i += 1;
+      continue;
+    }
+
+    if (ch === "<") {
+      angleDepth += 1;
+      expectTypeAtom = true;
+      i += 1;
+      continue;
+    }
+
+    if (ch === ">") {
+      angleDepth = Math.max(0, angleDepth - 1);
+      expectTypeAtom = false;
+      i += 1;
+      continue;
+    }
+
+    if (ch === "(") {
+      parenDepth += 1;
+      expectTypeAtom = true;
+      i += 1;
+      continue;
+    }
+
+    if (ch === ")") {
+      parenDepth = Math.max(0, parenDepth - 1);
+      expectTypeAtom = false;
+      i += 1;
+      continue;
+    }
+
+    if (ch === "{") {
+      braceDepth += 1;
+      expectTypeAtom = true;
+      i += 1;
+      continue;
+    }
+
+    if (ch === "}") {
+      braceDepth = Math.max(0, braceDepth - 1);
+      expectTypeAtom = false;
+      i += 1;
+      continue;
+    }
+
+    if (ch === "|" || ch === "," || ch === ":") {
+      expectTypeAtom = true;
+      i += 1;
+      continue;
+    }
+
+    if (ch === "?") {
+      expectTypeAtom = false;
+      i += 1;
+      continue;
+    }
+
+    if (ch === "[" && text[i + 1] === "]") {
+      expectTypeAtom = false;
+      i += 2;
+      continue;
+    }
+
+    if (/\s/.test(ch)) {
+      let j = i;
+      while (j < text.length && /\s/.test(text[j]!)) {
+        j += 1;
+      }
+
+      if (j >= text.length) {
+        i = j;
+        break;
+      }
+
+      const next = text[j]!;
+      const nested = angleDepth > 0 || parenDepth > 0 || braceDepth > 0;
+      if (nested) {
+        i = j;
+        continue;
+      }
+
+      if (
+        next === "|"
+        || next === ","
+        || next === ":"
+        || next === ">"
+        || next === ")"
+        || next === "}"
+        || next === "?"
+      ) {
+        i = j;
+        continue;
+      }
+
+      if (next === "[" && text[j + 1] === "]") {
+        i = j;
+        continue;
+      }
+
+      if (expectTypeAtom && /[A-Za-z_"']/.test(next)) {
+        i = j;
+        continue;
+      }
+
+      if (!expectTypeAtom && /[A-Za-z_"']/.test(next)) {
+        break;
+      }
+
+      i = j;
+      continue;
+    }
+
+    expectTypeAtom = false;
+    i += 1;
+  }
+
+  const type = text.slice(0, i).trim();
+  const description = text.slice(i).trim();
+
+  return {
+    type: type.length > 0 ? type : "unknown",
+    description: description.length > 0 ? description : undefined,
+  };
+}
+
+function applyFieldDocLine(field: FieldDoc, line: string): void {
+  const { cleanedText, defaultValue } = stripDefaultDirective(line);
+
+  if (defaultValue && !field.defaultValue) {
+    field.defaultValue = defaultValue;
+  }
+
+  if (cleanedText.trim().length > 0) {
+    field.descriptionLines.push(cleanedText);
+  }
+}
+
+function stripDefaultDirective(text: string): {
+  cleanedText: string;
+  defaultValue?: string;
+} {
+  let cursor = 0;
+  let capturedDefault: string | undefined;
+  const keptChunks: string[] = [];
+
+  while (cursor < text.length) {
+    const tail = text.slice(cursor);
+    const match = /\bdefault\s*=\s*/i.exec(tail);
+    if (!match) {
+      keptChunks.push(tail);
+      break;
+    }
+
+    const start = cursor + match.index;
+    const valueStart = start + match[0].length;
+    const parsed = readDefaultValue(text, valueStart);
+    if (!parsed) {
+      keptChunks.push(tail);
+      break;
+    }
+
+    keptChunks.push(text.slice(cursor, start));
+    if (!capturedDefault) {
+      capturedDefault = parsed.value.trim();
+    }
+
+    cursor = parsed.end;
+  }
+
+  return {
+    cleanedText: keptChunks.join(""),
+    defaultValue: capturedDefault,
+  };
+}
+
+function readDefaultValue(
+  source: string,
+  startIndex: number,
+): { value: string; end: number } | undefined {
+  let i = startIndex;
+  while (i < source.length && /\s/.test(source[i]!)) {
+    i += 1;
+  }
+
+  if (i >= source.length) {
+    return undefined;
+  }
+
+  const start = i;
+  const opening = source[i]!;
+
+  if (opening === '"' || opening === "'") {
+    i += 1;
+    while (i < source.length) {
+      const ch = source[i]!;
+      if (ch === "\\") {
+        i += 2;
+        continue;
+      }
+
+      i += 1;
+      if (ch === opening) {
+        break;
+      }
+    }
+
+    return {
+      value: source.slice(start, i),
+      end: i,
+    };
+  }
+
+  if (opening === "{" || opening === "[" || opening === "(") {
+    const pairs: Record<string, string> = {
+      "{": "}",
+      "[": "]",
+      "(": ")",
+    };
+
+    const stack: string[] = [pairs[opening]!];
+    i += 1;
+    let inQuote: '"' | "'" | null = null;
+
+    while (i < source.length) {
+      const ch = source[i]!;
+
+      if (inQuote) {
+        if (ch === "\\") {
+          i += 2;
+          continue;
+        }
+
+        i += 1;
+        if (ch === inQuote) {
+          inQuote = null;
+        }
+        continue;
+      }
+
+      if (ch === '"' || ch === "'") {
+        inQuote = ch;
+        i += 1;
+        continue;
+      }
+
+      if (ch === "{" || ch === "[" || ch === "(") {
+        stack.push(pairs[ch]!);
+        i += 1;
+        continue;
+      }
+
+      const expected = stack.at(-1);
+      if (expected && ch === expected) {
+        stack.pop();
+        i += 1;
+        if (stack.length === 0) {
+          break;
+        }
+        continue;
+      }
+
+      i += 1;
+    }
+
+    return {
+      value: source.slice(start, i),
+      end: i,
+    };
+  }
+
+  while (i < source.length && !/\s/.test(source[i]!)) {
+    i += 1;
+  }
+
+  return {
+    value: source.slice(start, i),
+    end: i,
+  };
+}
+
+async function collectLuaFiles(root: string): Promise<string[]> {
+  const out: string[] = [];
+
+  async function walk(current: string): Promise<void> {
+    const entries = await fs.readdir(current, { withFileTypes: true });
+    entries.sort((a, b) => a.name.localeCompare(b.name));
+
+    for (const entry of entries) {
+      const fullPath = path.join(current, entry.name);
+      if (entry.isDirectory()) {
+        await walk(fullPath);
+        continue;
+      }
+
+      if (entry.isFile() && fullPath.endsWith(".lua")) {
+        out.push(fullPath);
+      }
+    }
+  }
+
+  await walk(root);
+  return out;
+}
+
+async function readFileIfExists(filePath: string): Promise<string | undefined> {
+  try {
+    return await fs.readFile(filePath, "utf8");
+  } catch (error) {
+    if (
+      typeof error === "object"
+      && error !== null
+      && "code" in error
+      && error.code === "ENOENT"
+    ) {
+      return undefined;
+    }
+
+    throw error;
+  }
+}
+
+function normalizeWhitespace(text: string): string {
+  return text.replace(/\s+/g, " ").trim();
+}
+
+function normalizePath(value: string): string {
+  return value.replace(/\\/g, "/");
+}
+
+void main();
diff --git a/docs/tsconfig.json b/docs/tsconfig.json
new file mode 100644
index 0000000..defa730
--- /dev/null
+++ b/docs/tsconfig.json
@@ -0,0 +1,12 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
+    "strict": true,
+    "noEmit": true,
+    "skipLibCheck": true,
+    "verbatimModuleSyntax": true
+  },
+  "include": ["src/**/*.ts"]
+}