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

import bpy


ARMATURE_NAME = "WebGapArmatureSymmetrizeArmature"
OBJECT_NAME = "WebGapArmatureSymmetrizeObject"
SOURCE_BONE = "WebGapArmatureSymmetrizeSource.L"
MIRRORED_BONE = "WebGapArmatureSymmetrizeSource.R"
OTHER_BONE = "WebGapArmatureSymmetrizeOther"


def vector(value):
    return [round(float(component), 6) for component in value]


def ensure_edit_mode():
    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.symmetrize 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()
    bones = []
    for bone in armature.edit_bones:
        bones.append({
            "name": bone.name,
            "selected": bool(bone.select),
            "hidden": bool(bone.hide),
            "parent": bone.parent.name if bone.parent else None,
            "connected": bool(bone.use_connect),
            "head": vector(bone.head),
            "tail": vector(bone.tail),
        })
    return {
        "object": OBJECT_NAME,
        "armature": ARMATURE_NAME,
        "activeBone": armature.edit_bones.active.name if armature.edit_bones.active else None,
        "bones": bones,
    }


def stable(value):
    return {
        "object": value["object"],
        "armature": value["armature"],
        "activeBone": value["activeBone"],
        "bones": sorted(value["bones"], key=lambda bone: bone["name"]),
    }


def main():
    arguments = sys.argv[sys.argv.index("--") + 1 :]
    if len(arguments) != 2:
        raise SystemExit("usage: blender -b --factory-startup --python checker -- 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 = {bone["name"] for bone in before["bones"]}
    already_applied = MIRRORED_BONE in names and SOURCE_BONE in names
    if not already_applied:
        if names != {SOURCE_BONE, OTHER_BONE}:
            raise RuntimeError(f"unexpected armature.symmetrize fixture: {before}")
        if not next(bone for bone in before["bones"] if bone["name"] == SOURCE_BONE)["selected"]:
            raise RuntimeError(f"symmetrize source is not selected: {before}")
    ensure_edit_mode()
    poll = bool(bpy.ops.armature.symmetrize.poll())
    if not poll:
        raise RuntimeError("ARMATURE_OT_symmetrize poll failed")
    if not already_applied:
        result = bpy.ops.armature.symmetrize(direction="NEGATIVE_X")
        if result != {"FINISHED"}:
            raise RuntimeError(f"ARMATURE_OT_symmetrize returned {result}")
    after = state_report()
    by_name = {bone["name"]: bone for bone in after["bones"]}
    if MIRRORED_BONE not in by_name or SOURCE_BONE not in by_name or OTHER_BONE not in by_name:
        raise RuntimeError(f"symmetrize did not create the mirrored bone: {after}")
    source = by_name[SOURCE_BONE]
    mirrored = by_name[MIRRORED_BONE]
    other = by_name[OTHER_BONE]
    if source["head"] != [1.0, 0.0, 0.0] or source["tail"] != [1.0, 1.0, 0.0]:
        raise RuntimeError(f"symmetrize changed source geometry: {after}")
    if mirrored["head"] != [-1.0, 0.0, 0.0] or mirrored["tail"] != [-1.0, 1.0, 0.0]:
        raise RuntimeError(f"symmetrize mirror geometry mismatch: {after}")
    if other["selected"]:
        raise RuntimeError(f"symmetrize selected unrelated bone: {after}")
    bpy.ops.object.mode_set(mode="OBJECT")
    descriptor, temporary = tempfile.mkstemp(prefix="m16-armature-symmetrize-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 stable(reopened) != stable(after):
            raise RuntimeError(f"armature.symmetrize save/reopen drift: {after} != {reopened}")
        shutil.copyfile(temporary_path, fixture)
        report = {
            "schemaVersion": 1,
            "task": "M16-GAP-00263",
            "operation": "ARMATURE_SYMMETRIZE_DESKTOP",
            "fixture": str(fixture),
            "fixtureSha256": hashlib.sha256(fixture.read_bytes()).hexdigest(),
            "before": before,
            "after": reopened,
            "sourceBone": SOURCE_BONE,
            "mirroredBone": MIRRORED_BONE,
            "otherBone": OTHER_BONE,
            "direction": "NEGATIVE_X",
            "operatorStatus": "FINISHED" if not already_applied else "SKIPPED_ALREADY_APPLIED",
            "mainMutation": "MIRRORED_SELECTED_BONE" if not already_applied else "MIRRORED_BONE_ALREADY_PRESENT",
            "poll": poll,
            "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"armature-symmetrize-desktop-ok source={SOURCE_BONE} mirrored={MIRRORED_BONE} direction=negative_x saveReopen=exact")
    finally:
        temporary_path.unlink(missing_ok=True)


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