import random
import unittest
from edid import parse,dtd

def checksum(b):
    b[127]=(-sum(b[:127]))&255
    return bytes(b)

def base(ext=0):
    b=bytearray(128); b[:8]=bytes.fromhex('00ffffffffffff00'); b[8:10]=bytes.fromhex('4c2d')
    b[18:20]=bytes((1,4)); b[20]=0xa2; b[38:54]=b'\x01\x01'*8; b[126]=ext
    b[54:72]=bytes.fromhex('023a801871382d40582c4500fd1e1100001e')
    b[72:90]=b'\0\0\0\xfc\0TEST PANEL\n  '
    return bytearray(checksum(b))

class Tests(unittest.TestCase):
    def test_identity_and_dtd(self):
        r=parse(base()); self.assertEqual(r['基本信息']['显示器名称'],'TEST PANEL')
        self.assertEqual(r['基本信息']['厂家 PNP 代码'],'SAM')
        t=r['时序'][0]; self.assertEqual(t['分辨率'],'1920×1080p'); self.assertEqual(t['刷新率'],'60.000 Hz')
        self.assertEqual(t['同步'],'H+ V+'); self.assertEqual(t['水平有效/前肩/同步/后肩'],[1920,88,44,148])
    def test_standard(self):
        b=base(); b[38:40]=bytes((129,192)); r=parse(checksum(b))
        self.assertEqual(r['时序'][0]['分辨率'],'1280×720'); self.assertEqual(r['时序'][0]['刷新率'],'60 Hz')
    def test_cta(self):
        b=bytearray(128); payload=bytes.fromhex('429061 23090707 67030c0012343078 e3060c01')
        b[:4]=bytes((2,3,4+len(payload),0x70)); b[4:4+len(payload)]=payload
        r=parse(bytes(base(1))+checksum(b)); text=str(r)
        self.assertIn('1.2.3.4',text); self.assertIn('PQ / ST 2084',text); self.assertIn('3840×2160p 60 Hz',text)
        self.assertIn('600 MHz',text); self.assertIn('LPCM',text)
    def test_missing_extension(self):
        self.assertTrue(parse(base(2))['警告'])
    def test_bad_checksum_and_header(self):
        b=base(); b[0]=1; r=parse(b); self.assertTrue(r['警告']); self.assertIn('失败',r['校验'][0])
    def test_bounds(self):
        with self.assertRaises(ValueError): parse(b'\0'*127)
        b=bytearray(128); b[:5]=bytes((2,3,6,0,0x5f))
        self.assertIn('越界',str(parse(bytes(base(1))+checksum(b))['警告']))
    def test_unknown_extension(self):
        b=bytearray(128); b[0]=0x70
        self.assertIn('暂未解码',str(parse(bytes(base(1))+checksum(b))))
    def test_interlaced(self):
        b=bytes.fromhex('011d8018711c1620582c2500fd1e1100009e')
        t=dtd(b,'test'); self.assertEqual(t['分辨率'],'1920×1080i'); self.assertEqual(t['刷新率'],'60.000 Hz（场率）')
    def test_random_malformed(self):
        rng=random.Random(42)
        for _ in range(1000):
            b=bytearray(rng.randbytes(rng.randint(128,600))); b[18]=1; parse(b)

if __name__=='__main__': unittest.main()