"""
Teilt ils_library.dxf in einzelne DXF-Dateien pro Block auf.
Jede Ausgabedatei enthaelt den Block + alle seine Unterblock-Abhaengigkeiten.
Aufruf: python split_block_library.py
"""
import os
import sys
import ezdxf
from ezdxf.document import Drawing

# Pfade
SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
PROJECT_ROOT = os.path.dirname(SCRIPT_DIR)
LIB_PATH = os.path.join(PROJECT_ROOT, "data", "block_libraries", "ils_library.dxf")
OUT_DIR = os.path.join(PROJECT_ROOT, "data", "ils")

# Nur diese Bloecke exportieren (alle fuer den Vario-Foerderer relevanten)
EXPORT_PREFIXES = (
    "Vario_",
    "Staustrecke_",
    "_3D_AS_",
    "_3D_ES_",
)

# Abhaengigkeiten: KS_EIN und KS_AUS muessen immer mitgeliefert werden
ALWAYS_INCLUDE = {"KS_EIN", "KS_AUS"}


def collect_dependencies(src_doc: Drawing, blockname: str, visited: set) -> set:
    """Gibt alle Unterblock-Namen zurueck, die 'blockname' direkt oder transitiv benoetigt."""
    if blockname in visited:
        return visited
    visited.add(blockname)
    if blockname not in src_doc.blocks:
        return visited
    blk = src_doc.blocks[blockname]
    for entity in blk:
        if entity.dxftype() == "INSERT":
            ref = entity.dxf.name
            collect_dependencies(src_doc, ref, visited)
    return visited


def copy_block(src_doc: Drawing, dst_doc: Drawing, blockname: str):
    """Kopiert einen Block und seine Abhaengigkeiten von src nach dst."""
    deps = collect_dependencies(src_doc, blockname, set())

    for name in deps:
        if name not in src_doc.blocks:
            continue
        if name in dst_doc.blocks:
            continue

        src_blk = src_doc.blocks[name]

        # Neuen Block im Zieldokument anlegen
        dst_blk = dst_doc.blocks.new(
            name=name,
            base_point=src_blk.block.dxf.base_point if hasattr(src_blk.block.dxf, "base_point") else (0, 0, 0),
        )

        # Alle Entities kopieren (ausser BLOCK/ENDBLK - die werden automatisch erstellt)
        for entity in src_blk:
            try:
                dst_blk.add_entity(entity.copy())
            except Exception:
                pass


def export_block(src_doc: Drawing, blockname: str, out_dir: str):
    """Exportiert einen einzelnen Block als eigene DXF-Datei."""
    safe_name = blockname.replace("/", "_").replace("\\", "_")
    out_path = os.path.join(out_dir, safe_name + ".dxf")

    dst_doc = ezdxf.new(dxfversion="R2010")
    dst_doc.units = src_doc.units

    # Layer aus Quelldatei uebernehmen (nur die benutzten)
    for layer in src_doc.layers:
        if layer.dxf.name not in dst_doc.layers:
            try:
                dst_doc.layers.new(
                    name=layer.dxf.name,
                    dxfattribs={"color": layer.dxf.get("color", 7)},
                )
            except Exception:
                pass

    # Block + Abhaengigkeiten kopieren
    copy_block(src_doc, dst_doc, blockname)

    dst_doc.saveas(out_path)
    return out_path


def main():
    print(f"Lese Bibliothek: {LIB_PATH}")
    if not os.path.exists(LIB_PATH):
        print(f"FEHLER: Datei nicht gefunden: {LIB_PATH}")
        sys.exit(1)

    src_doc = ezdxf.readfile(LIB_PATH)
    print(f"  Geladen. Bloecke gesamt: {len(list(src_doc.blocks))}")

    os.makedirs(OUT_DIR, exist_ok=True)

    # Relevante Bloecke filtern
    to_export = []
    for blk in src_doc.blocks:
        name = blk.name
        if name.startswith("*"):
            continue
        if any(name.startswith(p) for p in EXPORT_PREFIXES) or name in ALWAYS_INCLUDE:
            to_export.append(name)

    print(f"  Zu exportierende Bloecke: {len(to_export)}")

    ok = 0
    fail = 0
    for name in sorted(to_export):
        try:
            out = export_block(src_doc, name, OUT_DIR)
            # KS_EIN/KS_AUS pruefen
            check_doc = ezdxf.readfile(out)
            has_ks_ein = "KS_EIN" in check_doc.blocks
            has_ks_aus = "KS_AUS" in check_doc.blocks
            ks_status = ""
            if name not in ALWAYS_INCLUDE:
                blk = check_doc.blocks[name]
                inserts = [e.dxf.name for e in blk if e.dxftype() == "INSERT"]
                has_ks_ein_ref = "KS_EIN" in inserts
                has_ks_aus_ref = "KS_AUS" in inserts
                ks_status = f"  KS_EIN={'ja' if has_ks_ein_ref else 'NEIN'}  KS_AUS={'ja' if has_ks_aus_ref else 'NEIN'}"
            print(f"  OK  {name}{ks_status}")
            ok += 1
        except Exception as e:
            print(f"  FEHLER  {name}: {e}")
            fail += 1

    print(f"\nErgebnis: {ok} exportiert, {fail} Fehler")
    print(f"Ausgabeverzeichnis: {OUT_DIR}")


if __name__ == "__main__":
    main()