#!/usr/bin/env python3
import hashlib
import json
import os
import pathlib
import shutil
import sys
import tempfile

import bpy


ARMATURE_NAME = "WebGapArmatureCollectionUnassignArmature"
OBJECT_NAME = "WebGapArmatureCollectionUnassignObject"
SOURCE_COLLECTION = "WebGapArmatureCollectionUnassignSource"
RETAINED_COLLECTION = "WebGapArmatureCollectionUnassignRetained"
BONE_NAME = "WebGapArmatureCollectionUnassignBone"


def ensure_edit_mode():
    obj = bpy.data.objects.get(OBJECT_NAME)
    armature = bpy.data.armatures.get(ARMATURE_NAME)
    if armature is None or obj is None or obj.type != "ARMATURE" or obj.data != armature:
        raise RuntimeError("armature.collection_unassign fixture is missing")
    bpy.context.view_layer.objects.active = obj
    obj.select_set(True)
    if obj.mode != "EDIT":
        bpy.ops.object.mode_set(mode="EDIT")
    return armature


def state_report():
    armature = ensure_edit_mode()
    selected_bones = sorted(bone.name for bone in armature.edit_bones if bone.select)
    bones = sorted(bone.name for bone in armature.edit_bones)
    bpy.ops.object.mode_set(mode="OBJECT")
    collections = []
    for index, collection in enumerate(armature.collections):
        collections.append(
            {
                "name": collection.name,
                "index": index,
                "bones": sorted(bone.name for bone in collection.bones),
            }
        )
    bpy.context.view_layer.objects.active = bpy.data.objects[OBJECT_NAME]
    bpy.ops.object.mode_set(mode="EDIT")
    return {
        "object": OBJECT_NAME,
        "armature": ARMATURE_NAME,
        "activeIndex": armature.collections.active_index,
        "bones": bones,
        "selectedBones": selected_bones,
        "collections": collections,
    }


def run_operator(already_unassigned):
    armature = ensure_edit_mode()
    poll = bool(bpy.ops.armature.collection_unassign.poll())
    if not poll:
        raise RuntimeError("ARMATURE_OT_collection_unassign poll failed")
    if not already_unassigned:
        result = bpy.ops.armature.collection_unassign()
        if result != {"FINISHED"}:
            raise RuntimeError(f"ARMATURE_OT_collection_unassign returned {result}")
    return poll, not already_unassigned


def main():
    arguments = sys.argv[sys.argv.index("--") + 1 :]
    if len(arguments) != 2:
        raise SystemExit(
            "usage: blender -b --factory-startup --python check-action-armature-collection-unassign-desktop.py -- FIXTURE REPORT"
        )
    fixture, output = (pathlib.Path(value).resolve() for value in arguments)
    bpy.ops.wm.open_mainfile(filepath=str(fixture), load_ui=False)
    before = state_report()
    expected_collections = [SOURCE_COLLECTION, RETAINED_COLLECTION]
    if [collection["name"] for collection in before["collections"]] != expected_collections:
        raise RuntimeError(f"unexpected collection_unassign collections: {before}")
    if before["activeIndex"] != 0 or before["selectedBones"] != [BONE_NAME]:
        raise RuntimeError(f"unexpected collection_unassign active/selection input: {before}")
    source_before = before["collections"][0]["bones"]
    retained_before = before["collections"][1]["bones"]
    if source_before == [] and retained_before == [BONE_NAME]:
        already_unassigned = True
    elif source_before == [BONE_NAME] and retained_before == [BONE_NAME]:
        already_unassigned = False
    else:
        raise RuntimeError(f"unexpected collection_unassign membership input: {before}")
    poll, changed = run_operator(already_unassigned)
    after = state_report()
    if after["activeIndex"] != 0 or after["selectedBones"] != [BONE_NAME]:
        raise RuntimeError(f"collection_unassign changed active or selection state: {after}")
    actual_members = {collection["name"]: collection["bones"] for collection in after["collections"]}
    expected_members = {SOURCE_COLLECTION: [], RETAINED_COLLECTION: [BONE_NAME]}
    if actual_members != expected_members:
        raise RuntimeError(f"collection_unassign did not remove only the active membership: {after}")

    bpy.ops.object.mode_set(mode="OBJECT")
    descriptor, temporary = tempfile.mkstemp(prefix="m16-armature-collection-unassign-reopen-", suffix=".blend")
    os.close(descriptor)
    temporary_path = pathlib.Path(temporary)
    try:
        bpy.ops.wm.save_as_mainfile(filepath=str(temporary_path), check_existing=False, compress=True)
        bpy.ops.wm.open_mainfile(filepath=str(temporary_path), load_ui=False)
        reopened = state_report()
        if reopened != after:
            raise RuntimeError(f"armature.collection_unassign save/reopen drift: {after} != {reopened}")
        shutil.copyfile(temporary_path, fixture)
        report = {
            "schemaVersion": 1,
            "task": "M16-GAP-00230",
            "operation": "ARMATURE_COLLECTION_UNASSIGN_DESKTOP",
            "fixture": str(fixture),
            "fixtureSha256": hashlib.sha256(fixture.read_bytes()).hexdigest(),
            "before": before,
            "after": reopened,
            "activeCollection": SOURCE_COLLECTION,
            "unassignedBone": BONE_NAME,
            "poll": poll,
            "operatorStatus": "FINISHED" if changed else "SKIPPED_ALREADY_APPLIED",
            "mainMutation": "ACTIVE_COLLECTION_MEMBERSHIP_REMOVED" if changed else "ACTIVE_COLLECTION_ALREADY_EMPTY",
            "saveReopen": "EXACT",
            "blenderVersion": bpy.app.version_string,
        }
        output.parent.mkdir(parents=True, exist_ok=True)
        output.write_text(json.dumps(report, indent=2, sort_keys=True) + "\n", encoding="utf-8")
        print("armature-collection-unassign-desktop-ok poll=true source=empty retained=bone saveReopen=exact")
    finally:
        temporary_path.unlink(missing_ok=True)


if __name__ == "__main__":
    try:
        main()
    except Exception as error:
        print(f"armature-collection-unassign-desktop-failed: {error}")
        raise SystemExit(1)