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/*
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 * dart-sass.ts
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 *
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 * Copyright (C) 2020-2025 Posit Software, PBC
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 */
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import { join } from "../deno_ral/path.ts";
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import { architectureToolsPath } from "./resources.ts";
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import { execProcess } from "./process.ts";
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import { TempContext } from "./temp.ts";
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import { lines } from "./text.ts";
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import { debug, info } from "../deno_ral/log.ts";
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import { existsSync } from "../deno_ral/fs.ts";
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import { warnOnce } from "./log.ts";
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import { isWindows } from "../deno_ral/platform.ts";
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export function dartSassInstallDir() {
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  return architectureToolsPath("dart-sass");
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}
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export async function dartSassVersion() {
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  return await dartCommand(["--version"]);
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}
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export async function dartCompile(
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  input: string,
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  outputFilePath: string,
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  temp: TempContext,
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  loadPaths?: string[],
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  compressed?: boolean,
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): Promise<string | undefined> {
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  // Write the scss to a file
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  // We were previously passing it via stdin, but that can be overflowed
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  const inputFilePath = temp.createFile({ suffix: ".scss" });
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  // Write the css itself to a file
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  Deno.writeTextFileSync(inputFilePath, input);
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  const args = [
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    inputFilePath,
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    outputFilePath,
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    "--style",
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    compressed ? "compressed" : "expanded",
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    "--quiet", // Remove this flag to get depedency warnings from SASS
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  ];
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  if (loadPaths) {
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    loadPaths.forEach((loadPath) => {
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      args.push(`--load-path=${loadPath}`);
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    });
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  }
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  await dartCommand(args);
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  return outputFilePath;
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}
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/**
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 * Options for dartCommand
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 */
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export interface DartCommandOptions {
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  /**
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   * Override the dart-sass install directory.
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   * Used for testing with non-standard paths (spaces, accented characters).
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   */
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  installDir?: string;
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}
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/**
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 * Resolve the dart-sass command and its base arguments.
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 *
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 * On Windows, calls dart.exe + sass.snapshot directly instead of going
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 * through sass.bat. The bundled sass.bat is a thin wrapper generated by
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 * dart_cli_pkg that just runs:
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 *   "%SCRIPTPATH%\src\dart.exe" "%SCRIPTPATH%\src\sass.snapshot" %arguments%
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 *
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 * Template source:
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 *   https://github.com/google/dart_cli_pkg/blob/main/lib/src/templates/standalone/executable.bat.mustache
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 * Upstream issue to ship standalone .exe instead of .bat + dart.exe:
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 *   https://github.com/google/dart_cli_pkg/issues/67
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 *
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 * Bypassing sass.bat avoids multiple .bat file issues on Windows:
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 * - Deno quoting bugs with spaced paths (#13997)
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 * - cmd.exe OEM code page misreading UTF-8 accented paths (#14267)
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 * - Enterprise group policy blocking .bat execution (#6651)
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 */
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function resolveSassCommand(options?: DartCommandOptions): {
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  cmd: string;
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  baseArgs: string[];
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} {
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  const installDir = options?.installDir;
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  if (installDir == null) {
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    // Only check env var override when no explicit installDir is provided.
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    // If QUARTO_DART_SASS doesn't exist on disk, fall through to use the
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    // bundled dart-sass at the default architectureToolsPath.
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    const dartOverrideCmd = Deno.env.get("QUARTO_DART_SASS");
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    if (dartOverrideCmd) {
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      if (!existsSync(dartOverrideCmd)) {
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        warnOnce(
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          `Specified QUARTO_DART_SASS does not exist, using built in dart sass.`,
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        );
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      } else {
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        return { cmd: dartOverrideCmd, baseArgs: [] };
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      }
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    }
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  }
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  const sassDir = installDir ?? architectureToolsPath("dart-sass");
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  if (isWindows) {
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    return {
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      cmd: join(sassDir, "src", "dart.exe"),
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      baseArgs: [join(sassDir, "src", "sass.snapshot")],
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    };
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  }
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  return { cmd: join(sassDir, "sass"), baseArgs: [] };
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}
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export async function dartCommand(
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  args: string[],
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  options?: DartCommandOptions,
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) {
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  const { cmd, baseArgs } = resolveSassCommand(options);
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  const result = await execProcess({
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    cmd,
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    args: [...baseArgs, ...args],
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    stdout: "piped",
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    stderr: "piped",
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  });
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  if (result.success) {
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    if (result.stderr) {
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      info(result.stderr);
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    }
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    return result.stdout;
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  } else {
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    debug(`[DART cmd]    : ${cmd}`);
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    debug(`[DART args]   : ${[...baseArgs, ...args].join(" ")}`);
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    debug(`[DART stdout] : ${result.stdout}`);
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    debug(`[DART stderr] : ${result.stderr}`);
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    const errLines = lines(result.stderr || "");
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    // truncate the last 2 lines (they include a pointer to the temp file containing
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    // all of the concatenated sass, which is more or less incomprehensible for users.
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    const errMsg = errLines.slice(0, errLines.length - 2).join("\n");
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    throw new Error("Theme file compilation failed:\n\n" + errMsg);
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  }
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}
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