"""R616：只替换冻结策略函数，控制输入与执行器，追踪首次分支和路径差异。"""
from copy import deepcopy
from difflib import unified_diff
from inspect import getsource

PRICES = [100, 100, 101, 99]
CONTROLS = {'data': PRICES, 'config': {'initial_cash': 1000, 'target_qty': 1},
            'engine': 'synthetic-next-price-v1'}


def signal_v1(current, previous):
    return current >= previous


def signal_v2(current, previous):
    return current > previous


def check_controls(left, right):
    if left != right:
        raise ValueError('non-code controls changed')


def run(strategy):
    cash, shares = CONTROLS['config']['initial_cash'], 0
    signals, targets, fills = {}, [], []
    for t in [1, 2]:
        signal = int(strategy(PRICES[t], PRICES[t-1]))
        signals[(t, 'S')] = signal
        target = signal * CONTROLS['config']['target_qty']
        weight = target * PRICES[t] / (cash + shares * PRICES[t])
        targets.append((t, target, weight))
        qty = target - shares
        if qty:
            fills.append((t+1, qty, PRICES[t+1]))
        cash -= qty * PRICES[t+1]
        shares = target
    return {'signals': signals, 'targets': targets, 'fills': fills,
            'equity': cash + shares * PRICES[-1]}


def first_signal_difference(left, right):
    for key in sorted(left.keys() | right.keys()):
        if key not in left or key not in right:
            return {'status': 'missing_record', 'key': key}
        if left[key] != right[key]:
            return {'status': 'changed', 'key': key, 'old': left[key], 'new': right[key]}
    return None


check_controls(CONTROLS, deepcopy(CONTROLS))
a, b = run(signal_v1), run(signal_v2)
first = first_signal_difference(a['signals'], b['signals'])
assert first == {'status': 'changed', 'key': (1, 'S'), 'old': 1, 'new': 0}
assert a['fills'] == [(2, 1, 101)] and b['fills'] == [(3, 1, 99)]
assert a['equity'] == 998 and b['equity'] == 1000
assert a['targets'][0][2] == .1 and b['targets'][0][2] == 0
assert a['signals'][(2,'S')] == b['signals'][(2,'S')] == 1
patch = ''.join(unified_diff(getsource(signal_v1).splitlines(True),
                            getsource(signal_v2).splitlines(True),
                            fromfile='v1', tofile='v2'))
assert '-    return current >= previous' in patch
assert '+    return current > previous' in patch
reordered = dict(reversed(list(a['signals'].items())))
assert first_signal_difference(a['signals'], reordered) is None
missing = dict(a['signals']); del missing[(2,'S')]
assert first_signal_difference(a['signals'], missing)['status'] == 'missing_record'
changed = deepcopy(CONTROLS); changed['config']['target_qty'] = 2
try:
    check_controls(CONTROLS, changed)
except ValueError:
    pass
else:
    raise AssertionError('mixed configuration accepted')
print('first_signal_session=1 security=S branch=equality old=1 new=0')
print('first_target_weight=0.1,0.0 old_fills=' + str(a['fills']) + ' new_fills=' + str(b['fills']))
print('final_equity=' + str((a['equity'],b['equity'])) + ' later_fill_difference=position_path')
print('row_reorder=equal missing_record=explicit mixed_controls=rejected')