from __future__ import annotations

import base64
import hashlib
import json
from pathlib import Path

import pytest

from app.fonts.store import FontCatalog, FontValidationError
from app.templates.store import TemplateStore, prepare_scene
from app.animations.store import AnimationStore

ID = "builtin:walnut-bus-8x16"


def scene(font=ID):
    return prepare_scene(dict(version=1, width=64, height=64,
        pixelRgb=base64.b64encode(bytes(64*64*3)).decode("ascii"),
        elements=[dict(id="text",type="text",text="高铁路",font=font,size=16,x=0,y=8,align="left",color="#FFFFFF")]))


class ChangingFont:
    def __init__(self, catalog):
        self.catalog, self.version = catalog, 1

    def render_version(self, identifier):
        return str(self.version)*64 if identifier == ID else None

    def resolve(self, identifier):
        return self.catalog.resolve(ID if self.version == 1 else "builtin:walnut-bus-16x32")


def test_template_cache_rebuilt_without_revision_or_record_change(tmp_path):
    owner=ChangingFont(FontCatalog(tmp_path))
    store=TemplateStore(tmp_path, font_resolver=owner.resolve)
    item=store.create("bus",scene())
    path=store.thumbnail_path(item["id"])
    record=store._record_path(item["id"])
    before_bytes, before_record = path.read_bytes(), record.read_bytes()
    assert "font_v=" in item["thumbnail_url"]
    owner.version=2
    restarted=TemplateStore(tmp_path,font_resolver=owner.resolve)
    updated=restarted.list()["templates"][0]
    assert updated["revision"] == item["revision"]
    assert record.read_bytes() == before_record
    assert path.read_bytes() != before_bytes
    assert updated["thumbnail_url"] != item["thumbnail_url"]
    stable=path.stat().st_mtime_ns
    TemplateStore(tmp_path,font_resolver=owner.resolve)
    assert path.stat().st_mtime_ns == stable


def test_animation_cache_rebuilt_without_scene_or_revision_change(tmp_path):
    owner=ChangingFont(FontCatalog(tmp_path))
    store=AnimationStore(tmp_path,font_resolver=owner.resolve)
    item=store.create_from_frames("bus",[dict(scene=scene(),duration_ms=100)])
    frame=store.get(item["id"])["frames"][0]
    stored_frame=store._read(item["id"])["frames"][0]
    path=store._thumb_dir(item["id"])/stored_frame["thumbnail"]
    record=store._path(item["id"])
    before_bytes, before_record = path.read_bytes(), record.read_bytes()
    owner.version=2
    restarted=AnimationStore(tmp_path,font_resolver=owner.resolve)
    updated=restarted.get(item["id"])
    assert updated["revision"] == item["revision"]
    assert record.read_bytes() == before_record
    assert path.read_bytes() != before_bytes
    assert updated["frames"][0]["thumbnail_url"] != frame["thumbnail_url"]
    stable=path.stat().st_mtime_ns
    AnimationStore(tmp_path,font_resolver=owner.resolve)
    assert path.stat().st_mtime_ns == stable


def test_unrelated_thumbnails_untouched(tmp_path):
    owner=ChangingFont(FontCatalog(tmp_path))
    store=TemplateStore(tmp_path,font_resolver=owner.resolve)
    item=store.create("normal",scene("default"))
    path=store.thumbnail_path(item["id"])
    stable=path.read_bytes(),path.stat().st_mtime_ns
    assert "font_v=" not in item["thumbnail_url"]
    owner.version=2
    TemplateStore(tmp_path,font_resolver=owner.resolve)
    assert (path.read_bytes(),path.stat().st_mtime_ns) == stable


def test_exact_obsolete_retirement_and_corruption_preservation(tmp_path, monkeypatch):
    import app.fonts.store as module
    bundle=Path(module.__file__).parent/'bundled'
    registration=json.loads((bundle/'manifest.json').read_text(encoding='utf-8'))
    old_payload=b'old-font-fixture'
    old_digest=hashlib.sha256(old_payload).hexdigest()
    registration['obsolete']=[old_digest]
    registration['aliases']={f'user:{old_digest}:0':ID}
    # Substitute only the registration reader, retaining real bundled font
    # files and checksum validation; fixture files never need old private state.
    real_read=Path.read_text
    def read(path,*args,**kwargs):
        if path == bundle/'manifest.json':return json.dumps(registration)
        return real_read(path,*args,**kwargs)
    monkeypatch.setattr(Path,'read_text',read)
    root=tmp_path/'fonts';root.mkdir()
    old=root/f'{old_digest}.font';old.write_bytes(old_payload)
    unrelated=root/'unregistered.font';unrelated.write_bytes(b'keep')
    catalog=FontCatalog(tmp_path)
    assert not old.exists()
    assert unrelated.read_bytes() == b'keep'
    assert catalog.resolve(f'user:{old_digest}:0') == catalog.resolve(ID)
    old.write_bytes(b'corrupt')
    with pytest.raises(FontValidationError,match='preserved'):
        FontCatalog(tmp_path)
    assert old.read_bytes() == b'corrupt'