Export ONLY the currently selected asset(s) to T3D (SLIM, with dialogs)

"""
UE 4.27.2 - Export ONLY the currently selected asset(s) to T3D (SLIM, with dialogs)

Exports only assets highlighted in the Content Browser (single or multi-select).
Mirrors the /Game/... hierarchy under DEST_ROOT. Existing files at the destination
that are NOT the selected asset are left untouched. Shows a popup at start (if
nothing exportable was selected) and at completion.

Setup:
    Requires "Python Editor Script Plugin" (Edit > Plugins > Scripting).

Usage:
    1. In the Content Browser, select one or more assets (Ctrl/Shift-click).
    2. File > Execute Python Script...  OR  right-click > Scripted Asset Actions.
"""

import os
import re
import unreal

# ============================================================
# CONFIG
# ============================================================
DEST_ROOT = r"F:/AI-ALIENS-T3D-slim"

WHITELIST = {
    "Blueprint",
    "WidgetBlueprint",
    "BehaviorTree",
    "BlackboardData",
    "EnvQuery",
    "UserDefinedEnum",
    "UserDefinedStruct",
    "AnimBlueprint",
    "Material",
    "MaterialFunction",
    "MaterialInstanceConstant",
}
# ============================================================


# ---- UI helpers ----------------------------------------------

def format_bytes(n):
    if n < 1024:
        return "%d B" % n
    if n < 1024 * 1024:
        return "%.1f KB" % (n / 1024.0)
    return "%.1f MB" % (n / (1024.0 * 1024.0))


def show_dialog(title, message):
    """Modal OK dialog. Falls back to Output Log if the API is missing."""
    try:
        unreal.EditorDialog.show_message(title, message, unreal.AppMsgType.OK)
    except Exception as e:
        unreal.log_warning("[Dialog fallback: %s] %s | %s" % (e, title, message))


# ---- Optimizer -----------------------------------------------

_DROP_LINE = re.compile(
    r"^\s*("
    r"NodePosX|NodePosY|NodeHeight|NodeWidth|"
    r"NodeGuid|BlueprintGuid|GraphGuid|VarGuid|"
    r"bLegacyNeedToPurgeSkelRefs|"
    r"bCommentBubblePinned|bCommentBubbleVisible|"
    r"bUserSetEnabledState|"
    r"PinPreviewIndex|"
    r"ThumbnailInfo"
    r")\s*="
)
_DROP_INDEXED = re.compile(r"^\s*(LastEditedDocuments|CategorySorting)\(\d+\)\s*=")

_SKIP_OBJECT_HINTS = ("SceneThumbnailInfo",)

_INLINE_STRIP = [
    re.compile(r"PersistentGuid=00000000000000000000000000000000,"),
    re.compile(r"bIsReference=False,"),
    re.compile(r"bIsConst=False,"),
    re.compile(r"bIsWeakPointer=False,"),
    re.compile(r"bIsUObjectWrapper=False,"),
    re.compile(r"bHidden=False,"),
    re.compile(r"bNotConnectable=False,"),
    re.compile(r"bDefaultValueIsReadOnly=False,"),
    re.compile(r"bDefaultValueIsIgnored=False,"),
    re.compile(r"bAdvancedView=False,"),
    re.compile(r"bOrphanedPin=False,"),
    re.compile(r'PinType\.PinSubCategory="",'),
    re.compile(r"PinType\.PinSubCategoryObject=None,"),
    re.compile(r"PinType\.PinSubCategoryMemberReference=\(\),"),
    re.compile(r"PinType\.PinValueType=\(\),"),
    re.compile(r"PinType\.ContainerType=None,"),
    re.compile(r'PinToolTip="[^"]*",'),
    re.compile(r"PinFriendlyName=NSLOCTEXT\([^)]*\),"),
    re.compile(r'AutogeneratedDefaultValue="[^"]*",'),
]


def optimize_t3d_text(text):
    try:
        lines = text.split("\n")
        out = []
        skip_depth = 0
        for raw in lines:
            line = raw.rstrip("\r")
            stripped = line.strip()
            if skip_depth > 0:
                if stripped.startswith("Begin Object"):
                    skip_depth += 1
                elif stripped.startswith("End Object"):
                    skip_depth -= 1
                continue
            if stripped.startswith("Begin Object") and any(
                h in stripped for h in _SKIP_OBJECT_HINTS
            ):
                skip_depth = 1
                continue
            if _DROP_LINE.match(line) or _DROP_INDEXED.match(line):
                continue
            for pat in _INLINE_STRIP:
                line = pat.sub("", line)
            out.append(line)
        return "\r\n".join(out)
    except Exception as e:
        unreal.log_warning("optimize_t3d_text failed (%s); keeping raw." % e)
        return text


# ---- Export helpers ------------------------------------------

def content_path_to_relative(content_path):
    if content_path.startswith("/Game/"):
        return content_path[len("/Game/"):]
    if content_path == "/Game":
        return ""
    return content_path.lstrip("/")


def export_asset(asset, out_file):
    task = unreal.AssetExportTask()
    task.object = asset
    task.filename = out_file
    task.automated = True
    task.prompt = False
    task.replace_identical = True
    task.use_file_archive = False
    task.write_empty_files = False
    return unreal.Exporter.run_asset_export_task(task)


def slim_file_in_place(path):
    with open(path, "rb") as f:
        raw = f.read()
    orig = len(raw)
    try:
        text = raw.decode("utf-8")
    except UnicodeDecodeError:
        text = raw.decode("utf-8", errors="replace")
    new_bytes = optimize_t3d_text(text).encode("utf-8")
    with open(path, "wb") as f:
        f.write(new_bytes)
    return orig, len(new_bytes)


# ---- Main ----------------------------------------------------

def main():
    selected = unreal.EditorUtilityLibrary.get_selected_asset_data()
    if not selected:
        show_dialog(
            "T3D Export",
            "Nothing selected.\n\nHighlight one or more assets in the Content Browser and try again.",
        )
        return

    total = len(selected)
    unreal.log("Destination : %s" % DEST_ROOT)
    unreal.log("Selected    : %d asset(s)" % total)

    exported = skipped = failed = 0
    skipped_names = []
    failed_list = []
    total_orig = 0
    total_new = 0

    for i, ad in enumerate(selected, start=1):
        name = str(ad.asset_name)
        cls = str(ad.asset_class)

        if cls not in WHITELIST:
            skipped += 1
            skipped_names.append("%s (%s)" % (name, cls))
            unreal.log_warning(
                "[%d/%d] SKIP (not in whitelist: %s)  %s" % (i, total, cls, name)
            )
            continue

        pkg_path = str(ad.package_path)
        asset = ad.get_asset()
        if asset is None:
            failed += 1
            failed_list.append("%s (load failed)" % name)
            continue

        rel = content_path_to_relative(pkg_path)
        out_dir = os.path.normpath(os.path.join(DEST_ROOT, rel))
        try:
            os.makedirs(out_dir, exist_ok=True)
        except Exception as e:
            failed += 1
            failed_list.append("%s (mkdir: %s)" % (name, e))
            continue

        out_file = os.path.join(out_dir, name + ".t3d")
        ok = export_asset(asset, out_file)
        if not ok:
            failed += 1
            failed_list.append(name)
            unreal.log_warning("[%d/%d] FAIL %s" % (i, total, name))
            continue

        try:
            orig, new = slim_file_in_place(out_file)
            total_orig += orig
            total_new += new
            reduction = (1 - new / orig) * 100 if orig else 0
            exported += 1
            unreal.log(
                "[%d/%d] OK   %s   %d -> %d bytes (-%.0f%%)"
                % (i, total, name, orig, new, reduction)
            )
        except Exception as e:
            exported += 1
            unreal.log_warning(
                "[%d/%d] OK (slim failed: %s) %s" % (i, total, e, name)
            )

    unreal.log("=" * 60)
    unreal.log(
        "Done.  Exported=%d   Skipped(not-whitelisted)=%d   Failed=%d"
        % (exported, skipped, failed)
    )
    if total_orig:
        overall = (1 - total_new / total_orig) * 100
        unreal.log(
            "Total size: %d -> %d bytes  (saved %.0f%%)"
            % (total_orig, total_new, overall)
        )

    # -- Popup summary --
    if exported > 0:
        msg = "Exported %d of %d asset(s) to:\n%s" % (exported, total, DEST_ROOT)
        if total_orig:
            overall = (1 - total_new / total_orig) * 100
            msg += "\n\nSize:  %s  ->  %s   (saved %.0f%%)" % (
                format_bytes(total_orig), format_bytes(total_new), overall,
            )
        if skipped:
            msg += "\n\nSkipped (not a supported type): %d" % skipped
        if failed:
            msg += "\nFailed: %d" % failed
        show_dialog("T3D Export Complete", msg)
    else:
        msg = "No assets were exported.\n\n"
        if skipped:
            preview = "\n".join("  - " + n for n in skipped_names[:8])
            more = "" if len(skipped_names) <= 8 else "\n  ...and %d more" % (len(skipped_names) - 8)
            msg += "Skipped (not a supported type): %d\n%s%s\n\n" % (skipped, preview, more)
        if failed:
            msg += "Failed: %d\n\n" % failed
        msg += "Supported: Blueprint, WidgetBlueprint, BehaviorTree, BlackboardData, EnvQuery, UserDefinedEnum/Struct, AnimBlueprint, Material, MaterialFunction, MaterialInstanceConstant."
        show_dialog("T3D Export - Nothing Done", msg)


main()