#target photoshop

/*
    Trim transparent pixels on all four sides.

    Equivalent Photoshop command:
    Image > Trim...
      Based On: Transparent Pixels
      Trim Away: Top, Bottom, Left, Right
*/

(function () {
    if (app.documents.length === 0) {
        alert("没有打开的文档。请打开一个文档后再运行此脚本。");
        return;
    }

    try {
        app.activeDocument.trim(
            TrimType.TRANSPARENT,
            true,  // Top
            true,  // Left
            true,  // Bottom
            true   // Right
        );
    } catch (error) {
        alert("Trim failed:\n" + error.message);
    }
}());