#!/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:
        raise RuntimeError("copy-driver fixture animation data is missing")
    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 = bpy.data.objects.get("WebGapAnimCopyDriverButtonObject")
    if obj is None:
        raise RuntimeError("copy-driver 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-copy-driver-button-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)
    before = state_report()
    expected = [{
        "path": '["drive_target"]',
        "index": 0,
        "expression": "frame * 2.0 + 1.0",
        "type": "SCRIPTED",
        "variableCount": 0,
    }]
    if before["drivers"] != expected:
        raise RuntimeError(f"unexpected copy_driver_button source driver: {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):
        result = bpy.ops.anim.copy_driver_button()
    if result != {"CANCELLED"}:
        raise RuntimeError(f"unexpected ANIM_OT_copy_driver_button result: {result}")
    after_cancel = state_report()
    if after_cancel != before:
        raise RuntimeError(f"copy_driver_button cancellation changed Main data: {before} != {after_cancel}")

    descriptor, temporary = tempfile.mkstemp(prefix="m16-anim-copy-driver-button-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 = state_report()
    finally:
        pathlib.Path(temporary).unlink(missing_ok=True)
    if before != after:
        raise RuntimeError("anim.copy_driver_button save/reopen drift")
    report = {
        "schemaVersion": 1,
        "task": "M16-GAP-00173",
        "operation": "ANIM_COPY_DRIVER_BUTTON_DESKTOP",
        "fixture": str(fixture),
        "fixtureSha256": hashlib.sha256(fixture.read_bytes()).hexdigest(),
        "drivers": after["drivers"],
        "value": after["value"],
        "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(f"anim-copy-driver-button-desktop-ok drivers=1 status={report['operatorStatus']} mainMutation=none saveReopen=exact")


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