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

import bpy


def action_channels(action):
    channels = []
    for layer in action.layers:
        for strip in layer.strips:
            for bag in strip.channelbags:
                for curve in bag.fcurves:
                    channels.append({
                        "path": curve.data_path,
                        "index": curve.array_index,
                        "frames": [round(float(keyframe.co.x), 6) for keyframe in curve.keyframe_points],
                    })
    channels.sort(key=lambda value: (value["path"], value["index"]))
    return channels


def action_report():
    obj = bpy.data.objects.get("WebGapActionUnlinkObject")
    if obj is None or obj.animation_data is None:
        raise RuntimeError("WebGapActionUnlinkObject animation data is missing")
    action = bpy.data.actions.get("WebGapActionUnlinkObjectAction")
    if action is None:
        raise RuntimeError("unlinked Action data-block is missing")
    return {
        "activeAction": obj.animation_data.action.name if obj.animation_data.action else None,
        "unlinkedAction": {
            "name": action.name,
            "users": action.users,
            "useFakeUser": action.use_fake_user,
            "channels": action_channels(action),
        },
    }


def main():
    arguments = sys.argv[sys.argv.index("--") + 1:]
    if len(arguments) != 2:
        raise SystemExit("usage: blender -b --python check-action-unlink-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 = action_report()
    if before["activeAction"] is not None or before["unlinkedAction"]["users"] != 1 or not before["unlinkedAction"]["useFakeUser"]:
        raise RuntimeError(f"unexpected action.unlink result: {before}")
    descriptor, temporary = tempfile.mkstemp(prefix="m16-action-unlink-reopen-", suffix=".blend")
    os.close(descriptor)
    try:
        bpy.ops.wm.save_as_mainfile(filepath=temporary, check_existing=False, compress=True)
        bpy.ops.wm.open_mainfile(filepath=temporary, load_ui=False)
        after = action_report()
    finally:
        pathlib.Path(temporary).unlink(missing_ok=True)
    if before != after:
        raise RuntimeError(f"action.unlink save/reopen drift: {before} != {after}")
    report = {
        "schemaVersion": 1,
        "task": "M16-GAP-00146",
        "operation": "ACTION_UNLINK_DESKTOP",
        "fixture": str(fixture),
        "fixtureSha256": hashlib.sha256(fixture.read_bytes()).hexdigest(),
        "action": after,
        "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("action-unlink-desktop-ok activeAction=none fakeUser=true saveReopen=exact")


if __name__ == "__main__":
    main()