"""合成保存筛选重跑与字段归因。"""
import json

old = {"AAA": {"price": 18, "eps": 1, "revision": "v1"},
       "BBB": {"price": 24, "eps": 1, "revision": "v1"},
       "CCC": {"price": 15, "eps": 1, "revision": "v1"},
       "DDD": {"price": 21, "eps": 1, "revision": "v1"},
       "FFF": {"price": 10, "eps": 1, "revision": "v1"}}
new = {"AAA": {"price": 22, "eps": 1, "revision": "v1"},
       "BBB": {"price": 24, "eps": 1.5, "revision": "v2", "event": "correction"},
       "DDD": {"price": 19, "eps": 1, "revision": "v1"},
       "EEE": {"price": 17, "eps": 1, "revision": "v1"},
       "FFF": {"price": 10, "eps": 1, "revision": "v1"}}

def run(snapshot):
    return {s for s, r in snapshot.items() if r["eps"] > 0 and r["price"] / r["eps"] < 20}

before, after = run(old), run(new)
changes = {}
for symbol in sorted(before ^ after):
    if symbol not in old or symbol not in new:
        cause = "universe"
    else:
        fields = [f for f in ("price", "eps") if old[symbol][f] != new[symbol][f]]
        cause = "+".join(fields)
        if "eps" in fields:
            cause += ":" + new[symbol].get("event", "unresolved")
    changes[symbol] = cause
assert run(old) == before
assert before == {"AAA", "CCC", "FFF"}
assert after == {"BBB", "DDD", "EEE", "FFF"}
assert changes == {"AAA": "price", "BBB": "eps:correction", "CCC": "universe", "DDD": "price", "EEE": "universe"}
assert old["BBB"]["revision"] != new["BBB"]["revision"]
print(json.dumps({"added": sorted(after-before), "removed": sorted(before-after),
                  "retained": sorted(before & after), "causes": changes}, sort_keys=True))