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

import bpy


def driver_report(obj):
    if obj is None or obj.animation_data is None:
        return []
    drivers = []
    for curve in obj.animation_data.drivers:
        driver = curve.driver
        drivers.append(
            {
                "path": curve.data_path,
                "index": curve.array_index,
                "expression": driver.expression if driver else "",
                "type": driver.type if driver else "",
                "variableCount": len(driver.variables) if driver else 0,
            }
        )
    drivers.sort(key=lambda value: (value["path"], value["index"]))
    return drivers


def state_report(obj):
    if obj is None:
        raise RuntimeError("driver-button-add fixture object is missing")
    return {"drivers": driver_report(obj), "value": round(float(obj["drive_target"]), 6)}


def main():
    arguments = sys.argv[sys.argv.index("--") + 1 :]
    if len(arguments) != 2:
        raise SystemExit(
            "usage: blender -b --python check-action-driver-button-add-desktop.py -- FIXTURE REPORT"
        )
    fixture, output = (pathlib.Path(value).resolve() for value in arguments)
    output.unlink(missing_ok=True)
    bpy.ops.wm.open_mainfile(filepath=str(fixture), load_ui=False)
    obj = bpy.data.objects.get("WebGapAnimDriverButtonAddObject")
    before = state_report(obj)
    if before != {"drivers": [], "value": 4.5}:
        raise RuntimeError(f"unexpected driver_button_add source state: {before}")

    window = bpy.context.window
    screen = window.screen
    area = next(candidate for candidate in screen.areas if candidate.type == "PROPERTIES")
    region = next(candidate for candidate in area.regions if candidate.type == "WINDOW")
    with bpy.context.temp_override(window=window, screen=screen, area=area, region=region):
        poll = bool(bpy.ops.anim.driver_button_add.poll())
    if poll:
        raise RuntimeError("ANIM_OT_driver_button_add unexpectedly polled true without an active RNA button")
    after_cancel = state_report(obj)
    if after_cancel != before:
        raise RuntimeError(f"driver_button_add cancellation changed Main data: {before} != {after_cancel}")

    descriptor, temporary = tempfile.mkstemp(prefix="m16-anim-driver-button-add-reopen-", suffix=".blend")
    os.close(descriptor)
    pathlib.Path(temporary).unlink(missing_ok=True)
    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 = state_report(bpy.data.objects.get("WebGapAnimDriverButtonAddObject"))
    finally:
        pathlib.Path(temporary).unlink(missing_ok=True)
    if before != after:
        raise RuntimeError("anim.driver_button_add save/reopen drift")
    report = {
        "schemaVersion": 1,
        "task": "M16-GAP-00174",
        "operation": "ANIM_DRIVER_BUTTON_ADD_DESKTOP",
        "fixture": str(fixture),
        "fixtureSha256": hashlib.sha256(fixture.read_bytes()).hexdigest(),
        "drivers": after["drivers"],
        "value": after["value"],
        "poll": poll,
        "operatorStatus": "CANCELLED",
        "mainMutation": "NONE",
        "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("anim-driver-button-add-desktop-ok poll=false status=CANCELLED mainMutation=none saveReopen=exact")


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