import * as yaml from 'yaml';
import {
FrontmatterResult,
WikiLink,
Heading,
TextOccurrence,
Position,
} from './types.js';
export function parseFrontmatter(content: string): FrontmatterResult {
const lines = content.split('\n');
if (lines[0]?.trim() !== '---') {
return {
data: null,
error: null,
rawYaml: null,
contentStartLine: 0,
};
}
let endIndex = -1;
for (let i = 1; i < lines.length; i++) {
if (lines[i].trim() === '---') {
endIndex = i;
break;
}
}
if (endIndex === -1) {
return {
data: null,
error: 'Frontmatter missing closing delimiter',
rawYaml: lines.slice(1).join('\n'),
contentStartLine: 0,
};
}
const yamlContent = lines.slice(1, endIndex).join('\n');
if (yamlContent.trim() === '') {
return {
data: {},
error: null,
rawYaml: '',
contentStartLine: endIndex + 1,
};
}
try {
const parsed = yaml.parse(yamlContent);
return {
data: parsed as Record<string, unknown>,
error: null,
rawYaml: yamlContent,
contentStartLine: endIndex + 1,
};
} catch (error: unknown) {
const err = error as Error;
return {
data: null,
error: `YAML parse error: ${err.message}`,
rawYaml: yamlContent,
contentStartLine: endIndex + 1,
};
}
}
export function serializeFrontmatter(fm: Record<string, unknown>): string {
return yaml.stringify(fm).trim();
}
export function updateFrontmatterInContent(
content: string,
updates: Record<string, unknown>
): string {
const parsed = parseFrontmatter(content);
const lines = content.split('\n');
const newFrontmatter = serializeFrontmatter(updates);
if (parsed.data === null && parsed.error === null) {
return `---\n${newFrontmatter}\n---\n${content}`;
}
if (parsed.error) {
const endIndex = lines.findIndex((line, idx) => idx > 0 && line.trim() === '---');
if (endIndex > 0) {
const contentAfterFrontmatter = lines.slice(endIndex + 1).join('\n');
return `---\n${newFrontmatter}\n---\n${contentAfterFrontmatter}`;
}
return `---\n${newFrontmatter}\n---\n${content}`;
}
const contentAfterFrontmatter = lines.slice(parsed.contentStartLine).join('\n');
return `---\n${newFrontmatter}\n---\n${contentAfterFrontmatter}`;
}
const WIKILINK_PATTERNS = {
embed: /!\[\[([^\]#|]+)(?:#([^\]|]+))?(?:\|([^\]]+))?\]\]/g,
link: /(?<!!)\[\[([^\]#|]+)(?:#([^\]|]+))?(?:\|([^\]]+))?\]\]/g,
};
export function extractWikilinks(content: string): WikiLink[] {
const links: WikiLink[] = [];
const lines = content.split('\n');
lines.forEach((line, lineIndex) => {
for (const match of line.matchAll(WIKILINK_PATTERNS.embed)) {
links.push({
raw: match[0],
target: match[1].trim(),
heading: match[2]?.trim() || null,
alias: match[3]?.trim() || null,
isEmbed: true,
line: lineIndex + 1,
column: match.index!,
});
}
for (const match of line.matchAll(WIKILINK_PATTERNS.link)) {
links.push({
raw: match[0],
target: match[1].trim(),
heading: match[2]?.trim() || null,
alias: match[3]?.trim() || null,
isEmbed: false,
line: lineIndex + 1,
column: match.index!,
});
}
});
return links;
}
export function replaceWikilinkTarget(
content: string,
oldTarget: string,
newTarget: string
): string {
const links = extractWikilinks(content);
let result = content;
let offset = 0;
for (const link of links) {
if (link.target === oldTarget) {
const newLink = link.raw.replace(
`[[${oldTarget}`,
`[[${newTarget}`
);
const lines = result.split('\n');
const lineIndex = link.line - 1;
const line = lines[lineIndex];
const col = link.column + offset;
lines[lineIndex] =
line.substring(0, col) +
newLink +
line.substring(col + link.raw.length);
result = lines.join('\n');
offset += newLink.length - link.raw.length;
}
}
return result;
}
export function insertWikilink(
content: string,
link: string,
position: Position
): string {
const lines = content.split('\n');
const lineIndex = position.line - 1;
if (lineIndex < 0 || lineIndex >= lines.length) {
throw new Error(`Invalid line number: ${position.line}`);
}
const line = lines[lineIndex];
const before = line.substring(0, position.column);
const after = line.substring(position.column);
lines[lineIndex] = `${before}[[${link}]]${after}`;
return lines.join('\n');
}
export function extractHeadings(content: string): Heading[] {
const headings: Heading[] = [];
const lines = content.split('\n');
const headingRegex = /^(#{1,6})\s+(.+)$/;
lines.forEach((line, index) => {
const match = line.match(headingRegex);
if (match) {
const level = match[1].length;
const text = match[2].trim();
const id = text
.toLowerCase()
.replace(/[^\w\s-]/g, '')
.replace(/\s+/g, '-');
headings.push({
level,
text,
line: index + 1,
id,
});
}
});
return headings;
}
export function findTextOccurrences(
content: string,
pattern: string,
isRegex: boolean = false
): TextOccurrence[] {
const occurrences: TextOccurrence[] = [];
const lines = content.split('\n');
const regex = isRegex
? new RegExp(pattern, 'gi')
: new RegExp(escapeRegex(pattern), 'gi');
lines.forEach((line, lineIndex) => {
for (const match of line.matchAll(regex)) {
const column = match.index!;
const contextStart = Math.max(0, column - 50);
const contextEnd = Math.min(line.length, column + match[0].length + 50);
occurrences.push({
line: lineIndex + 1,
column,
matchText: match[0],
contextBefore: line.substring(contextStart, column),
contextAfter: line.substring(column + match[0].length, contextEnd),
});
}
});
return occurrences;
}
export function removeWikilink(content: string, target: string): string {
const links = extractWikilinks(content);
const linesToRemove = links
.filter((link) => link.target === target)
.reverse();
let result = content;
for (const link of linesToRemove) {
const lines = result.split('\n');
const lineIndex = link.line - 1;
const line = lines[lineIndex];
lines[lineIndex] =
line.substring(0, link.column) +
line.substring(link.column + link.raw.length);
result = lines.join('\n');
}
return result;
}
export function getLineContext(content: string, lineNumber: number): string {
const lines = content.split('\n');
const lineIndex = lineNumber - 1;
if (lineIndex < 0 || lineIndex >= lines.length) {
return '';
}
return lines[lineIndex];
}
function escapeRegex(str: string): string {
return str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
}
