# Stage 43: open her in the Blender GUI on a slow, endless turntable.
#
#   blender <blend> --python 43_spin.py
#
# Runs inside the GUI session. Puts a linear 360-degree Z rotation on the body over SECONDS_PER_TURN
# and starts playback; the scene loops, and because the last frame is the same pose as the first,
# the turn is seamless and runs until you stop it.
#
# sync_mode is set to FRAME_DROP on purpose: left at the default, Blender plays this 32k mesh as
# fast as the viewport can draw it, which is far faster than the fps you asked for. FRAME_DROP
# makes playback honour real time, so "slow" actually means slow.
import bpy
import math

SECONDS_PER_TURN = 50.0
FPS = 24


def setup():
    ob = max([o for o in bpy.data.objects if o.type == 'MESH'],
             key=lambda o: len(o.data.vertices))
    bpy.context.view_layer.objects.active = ob
    for o in bpy.data.objects:
        o.select_set(o is ob)

    scn = bpy.context.scene
    scn.render.fps = FPS
    scn.sync_mode = 'FRAME_DROP'
    n = int(round(SECONDS_PER_TURN * FPS))
    scn.frame_start = 1
    scn.frame_end = n                      # frame n+1 would repeat frame 1, so end at n
    scn.frame_set(1)

    # Blender 5.x uses slotted actions, so `action.fcurves` no longer exists and reaching the
    # curves means walking layers/strips/channelbags. Not needed: set the interpolation default
    # BEFORE inserting, and let the scene's loop supply the extrapolation. A constant-interpolated
    # turntable would visibly stutter, so LINEAR here is the whole point.
    bpy.context.preferences.edit.keyframe_new_interpolation_type = 'LINEAR'
    ob.animation_data_clear()
    ob.rotation_mode = 'XYZ'
    ob.rotation_euler = (0.0, 0.0, 0.0)
    ob.keyframe_insert("rotation_euler", index=2, frame=1)
    ob.rotation_euler = (0.0, 0.0, 2.0 * math.pi)
    ob.keyframe_insert("rotation_euler", index=2, frame=n + 1)

    for area in bpy.context.screen.areas:
        if area.type != 'VIEW_3D':
            continue
        sp = area.spaces.active
        sp.shading.type = 'MATERIAL'
        sp.shading.use_scene_lights = False
        sp.shading.use_scene_world = False
        sp.overlay.show_floor = False
        sp.overlay.show_axis_x = False
        sp.overlay.show_axis_y = False
        sp.overlay.show_text = False
        sp.overlay.show_cursor = False
        sp.overlay.show_object_origins = False
        sp.clip_start = 0.01
        sp.clip_end = 100.0
        for region in area.regions:
            if region.type == 'WINDOW':
                with bpy.context.temp_override(area=area, region=region):
                    bpy.ops.view3d.view_axis(type='FRONT')
                    bpy.ops.view3d.view_selected()
                    # pull back a little: her arms swing toward camera through the turn
                    bpy.ops.view3d.zoom(delta=-2)
    ob.select_set(False)                   # drop the selection outline for a clean look

    for window in bpy.context.window_manager.windows:
        scr = window.screen
        for area in scr.areas:
            if area.type == 'VIEW_3D':
                with bpy.context.temp_override(window=window, screen=scr, area=area):
                    bpy.ops.screen.animation_play()
                break
    print(f"SPIN_READY {n} frames at {FPS} fps = {SECONDS_PER_TURN:.0f}s per turn", flush=True)
    return None


bpy.app.timers.register(setup, first_interval=0.6)