#!/usr/bin/env python3
"""EAN-13 生成本地复算（湖北易千亿彩 · 69803093 段）
结构: 8位前缀 69803093 + 4位产品码 + 1位校验
校验: 前12位左起权重 1,3,1,3... ; check=(10-sum%10)%10"""
def ean13_check(d12: str) -> int:
    total = sum(int(d) * (1 if i % 2 == 0 else 3) for i, d in enumerate(d12))
    return (10 - total % 10) % 10

def make(pc: int) -> str:
    d12 = "69803093" + f"{pc:04d}"
    return d12 + str(ean13_check(d12))

if __name__ == "__main__":
    # 1) 复算文档里的例子，验证算法
    print("=== 算法自检 ===")
    for pc, expect in ((2900, "6980309329009"), (3400, "6980309334003"), (9999, "6980309399996")):
        got = make(pc)
        print(f"  pc {pc:>4} → {got}  {'✅' if got == expect else '❌ 期望 ' + expect}")
    doc_wrong = make(1000)
    print(f"  pc 1000 → {doc_wrong}  （文档写 6980309310004，实为 {doc_wrong} ← 文档该例有误）")
    print(f"  pc 0000 → {make(0)}")
    print()
    # 2) 为 Walmart 分配 47 个（pc 3400..3446）
    START, N = 3400, 47
    codes = [make(START + i) for i in range(N)]
    assert len(set(codes)) == N, "批内重复"
    for c in codes:
        assert ean13_check(c[:12]) == int(c[12]), f"校验位错 {c}"
    print(f"=== 分配 pc {START}~{START+N-1} 共 {N} 个（校验位全部复核通过）===")
    for i, c in enumerate(codes):
        print(f"  {START+i:>4}  {c}")
    open("/home/admin9webs/walmart建品/ean_69803093_%d-%d.txt" % (START, START + N - 1), "w").write("\n".join(codes) + "\n")
    print(f"\n已落盘: ean_69803093_{START}-{START+N-1}.txt")
    print(f"下一号应为 pc {START+N} → {make(START+N)}；剩余 {9999-(START+N)+1} 个")