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

import bpy


ARMATURE_NAME = "WebGapArmatureCollectionAddArmature"
OBJECT_NAME = "WebGapArmatureCollectionAddObject"
SOURCE_COLLECTION = "WebGapArmatureCollectionAddExisting"
NEW_COLLECTION = "Bones"
BONE_NAME = "WebGapArmatureCollectionAddBone"


def state_report():
    armature = bpy.data.armatures.get(ARMATURE_NAME)
    obj = bpy.data.objects.get(OBJECT_NAME)
    if armature is None or obj is None or obj.type != "ARMATURE" or obj.data != armature:
        raise RuntimeError("armature.collection_add fixture is missing")
    collections = []
    for index, collection in enumerate(armature.collections):
        collections.append({"name": collection.name, "index": index, "bones": sorted(bone.name for bone in collection.bones)})
    return {"object": OBJECT_NAME, "armature": ARMATURE_NAME, "activeIndex": armature.collections.active_index, "collections": collections}


def run_operator(already_added):
    bpy.context.view_layer.objects.active = bpy.data.objects[OBJECT_NAME]
    bpy.data.objects[OBJECT_NAME].select_set(True)
    armature = bpy.data.armatures[ARMATURE_NAME]
    if not already_added:
        armature.collections.active_index = 0
    poll = bool(bpy.ops.armature.collection_add.poll())
    if not poll:
        raise RuntimeError("ARMATURE_OT_collection_add poll failed")
    if not already_added:
        result = bpy.ops.armature.collection_add()
        if result != {"FINISHED"}:
            raise RuntimeError(f"ARMATURE_OT_collection_add returned {result}")
    return poll, not already_added


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-add-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()
    names = {collection["name"] for collection in before["collections"]}
    if names == {SOURCE_COLLECTION, NEW_COLLECTION}:
        already_added = True
    elif names == {SOURCE_COLLECTION}:
        already_added = False
    else:
        raise RuntimeError(f"unexpected collection_add input: {before}")
    poll, changed = run_operator(already_added)
    after = state_report()
    if len(after["collections"]) != 2:
        raise RuntimeError(f"collection_add did not produce exactly two collections: {before} -> {after}")
    source = next((collection for collection in after["collections"] if collection["name"] == SOURCE_COLLECTION), None)
    added = next((collection for collection in after["collections"] if collection["name"] == NEW_COLLECTION), None)
    if source is None or added is None or source["index"] != 0 or added["index"] != 1:
        raise RuntimeError(f"collection_add produced unexpected collections: {after}")
    if source["bones"] != [BONE_NAME] or added["bones"]:
        raise RuntimeError(f"collection_add changed collection membership: {after}")

    descriptor, temporary = tempfile.mkstemp(prefix="m16-armature-collection-add-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_add save/reopen drift: {after} != {reopened}")
        shutil.copyfile(temporary_path, fixture)
        report = {
            "schemaVersion": 1,
            "task": "M16-GAP-00221",
            "operation": "ARMATURE_COLLECTION_ADD_DESKTOP",
            "fixture": str(fixture),
            "fixtureSha256": hashlib.sha256(fixture.read_bytes()).hexdigest(),
            "before": before,
            "after": reopened,
            "alreadyAdded": not changed,
            "poll": poll,
            "operatorStatus": "FINISHED" if changed else "SKIPPED_ALREADY_APPLIED",
            "mainMutation": "BONE_COLLECTION_ADDED" if changed else "ALREADY_BONE_COLLECTION_ADDED",
            "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-add-desktop-ok poll=true collection=Bones saveReopen=exact")
    finally:
        temporary_path.unlink(missing_ok=True)


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