/**
* Copyright (c) 2026 Ivan Iraci <ivan.iraci@professioneit.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
import type { TextEdit } from 'vscode-languageserver-protocol';
import type { RenameInput } from '../schemas/tool-schemas.js';
import type { RenameResponse, RenameEdit } from '../types.js';
import { prepareFile, toPosition } from './utils.js';
import { fromLspRange, getLineContent } from '../utils/position.js';
import { uriToPath, readFile } from '../utils/uri.js';
import { LSPError, LSPErrorCode } from '../types.js';
import * as fs from 'fs/promises';
/**
* Convert TextEdit to RenameEdit.
*/
async function textEditToRenameEdit(
edit: TextEdit,
uri: string,
cachedContent?: string
): Promise<RenameEdit> {
const filePath = uriToPath(uri);
let content = cachedContent;
if (!content) {
try {
content = await readFile(filePath);
} catch {
content = '';
}
}
const { start, end } = fromLspRange(edit.range, content);
const contextLine = getLineContent(content, start.line) ?? '';
return {
range: { start, end },
new_text: edit.newText,
context: contextLine.trim(),
};
}
/**
* Apply edits to a file.
*/
async function applyEditsToFile(
filePath: string,
edits: TextEdit[]
): Promise<void> {
// Read current content
const content = await readFile(filePath);
// Sort edits by position in reverse order (apply from end to start)
// to maintain correct positions for earlier edits
const sortedEdits = [...edits].sort((a, b) => {
if (a.range.start.line !== b.range.start.line) {
return b.range.start.line - a.range.start.line;
}
return b.range.start.character - a.range.start.character;
});
// Apply edits
const lines = content.split('\n');
let currentContent = content;
for (const edit of sortedEdits) {
// Calculate byte offsets
let startOffset = 0;
for (let i = 0; i < edit.range.start.line; i++) {
startOffset += (lines[i]?.length ?? 0) + 1; // +1 for newline
}
startOffset += edit.range.start.character;
let endOffset = 0;
for (let i = 0; i < edit.range.end.line; i++) {
endOffset += (lines[i]?.length ?? 0) + 1;
}
endOffset += edit.range.end.character;
// Apply the edit
currentContent =
currentContent.substring(0, startOffset) +
edit.newText +
currentContent.substring(endOffset);
}
// Write back
await fs.writeFile(filePath, currentContent, 'utf-8');
}
/**
* Handle lsp_rename tool call.
*/
export async function handleRename(
input: RenameInput
): Promise<RenameResponse> {
const { file_path, line, column, new_name, dry_run } = input;
const { client, uri, content } = await prepareFile(file_path);
// Convert position
const position = toPosition(line, column, content);
// First, check if rename is valid at this position
const prepareResult = await client.prepareRename(uri, position);
if (!prepareResult) {
throw new LSPError(
LSPErrorCode.RENAME_NOT_ALLOWED,
'Rename is not allowed at this position',
'Move cursor to a renameable symbol (variable, function, class, etc.)',
{ file_path, position: { line, column } }
);
}
// Extract original name if available
let originalName: string | undefined;
if ('placeholder' in prepareResult) {
originalName = prepareResult.placeholder;
}
// Perform rename
const workspaceEdit = await client.rename(uri, position, new_name);
if (!workspaceEdit || !workspaceEdit.changes) {
const emptyResult: RenameResponse = {
changes: {},
files_affected: 0,
edits_count: 0,
applied: false,
};
if (originalName) {
emptyResult.original_name = originalName;
}
return emptyResult;
}
// Convert to our format
const changes: Record<string, RenameEdit[]> = {};
let totalEdits = 0;
// Cache file contents to avoid reading the same file multiple times
const contentCache = new Map<string, string>();
contentCache.set(uri, content);
for (const [fileUri, edits] of Object.entries(workspaceEdit.changes)) {
const filePath = uriToPath(fileUri);
// Get or cache content
let fileContent = contentCache.get(fileUri);
if (!fileContent) {
try {
fileContent = await readFile(filePath);
contentCache.set(fileUri, fileContent);
} catch {
fileContent = '';
}
}
// Convert edits
const renameEdits: RenameEdit[] = [];
for (const edit of edits) {
renameEdits.push(await textEditToRenameEdit(edit, fileUri, fileContent));
totalEdits++;
}
changes[filePath] = renameEdits;
}
// Apply changes if not dry run
if (!dry_run) {
for (const [fileUri, edits] of Object.entries(workspaceEdit.changes)) {
const filePath = uriToPath(fileUri);
await applyEditsToFile(filePath, edits);
}
}
const response: RenameResponse = {
changes,
files_affected: Object.keys(changes).length,
edits_count: totalEdits,
applied: !dry_run,
};
if (originalName) {
response.original_name = originalName;
}
return response;
}
