"""Golden-manifest tests for the Connac2 container extractor.

Runs against whatever MediaTek blobs exist on this host (skip otherwise).
Golden values observed from linux-firmware snapshot 2026-04-20; when a value
here fails against a newer snapshot, the blob changed — update the golden
value *and* note it in the changelog, don't silently absorb it.
"""
import os
import subprocess
import sys
import unittest
from pathlib import Path

REPO = Path(__file__).resolve().parent.parent
FW = Path(os.environ.get('MTK_FW_DIR', '/lib/firmware/mediatek'))

# filename -> (chip_id, eco, n_region, hidden_trailer_string_or_None)
# Golden values observed from linux-firmware HEAD (2026-06-19 tree:
# mt7981/mt7986 = 20260515 builds; mt7915/mt7916 = 2022/2024 builds,
# unchanged since). When a value here fails against a newer snapshot, the
# blob changed — update the golden *and* record the diff (docs/reports/).
GOLDEN_WM = {
    'mt7981_wm.bin': (0x14, 0, 11,
                      't-neptune-main-mt7915-1953-MT7981_MP2111_IMP-20260515121129'),
    'mt7986_wm.bin': (0x0f, 0, 11,
                      't-neptune-main-mt7915-1953-MT7986_MP2111_IMP-20260515120228'),
    'mt7916_wm.bin': (0x13, 0, 9,
                      't-neptune-main-mt7915-1953-MT7916_MP2111_IMP-20240823170147'),
    'mt7915_wm.bin': (0x0b, 1, 7,
                      't-neptune-mp-mt7915-2045-MT7915_MP_7_4_2045-20220929103802'),
}
GOLDEN_WA = {
    'mt7981_wa.bin': (0x00, 0, 3, None),
    'mt7986_wa.bin': (0x00, 0, 3, None),
    'mt7916_wa.bin': (0x00, 0, 3, None),
    'mt7915_wa.bin': (0x00, 1, 3, None),
}


def parse(path: Path, out: Path) -> dict:
    out.mkdir(parents=True, exist_ok=True)
    sys.path.insert(0, str(REPO / 'tools'))
    import mtk_fw_extract as x
    return (x.carve_patch if 'patch' in path.name else x.carve_ram)(path, out)


class LayoutClosure(unittest.TestCase):
    """sum(region.len) + hidden trailer + table + trailer == file size."""

    def test_closure(self):
        blobs = sorted(FW.glob('mt79*_wm.bin')) + sorted(FW.glob('mt79*_wa.bin'))
        if not blobs:
            self.skipTest('no mediatek blobs on this host')
        import struct
        T = struct.Struct('<5B2s10s15sI')
        R = struct.Struct('<III4sIIBB14s')
        for p in blobs:
            with self.subTest(blob=p.name):
                d = p.read_bytes()
                n = d[len(d) - T.size + 2]
                tbl = len(d) - T.size - n * R.size
                data_end = sum(R.unpack_from(d, tbl + i * R.size)[5]
                               for i in range(n))
                self.assertEqual(
                    data_end + (tbl - data_end) + n * R.size + T.size, len(d),
                    'layout does not close')


class GoldenRAM(unittest.TestCase):

    def run_one(self, name, golden, outdir):
        p = FW / name
        if not p.exists():
            self.skipTest(f'{name} not present')
        info = parse(p, outdir)
        chip, eco, n, hidden = golden
        self.assertEqual(info['chip_id'], chip, name)
        self.assertEqual(info['eco'], eco, name)
        self.assertEqual(info['n_region'], n, name)
        ht = info.get('hidden_trailer', {})
        self.assertEqual(ht.get('string'), hidden, name)

    def test_wm(self):
        for name, golden in GOLDEN_WM.items():
            with self.subTest(blob=name):
                self.run_one(name, golden, REPO / 'extracted' / 'test_wm')

    def test_wa(self):
        for name, golden in GOLDEN_WA.items():
            with self.subTest(blob=name):
                self.run_one(name, golden, REPO / 'extracted' / 'test_wa')


class GoldenPatch(unittest.TestCase):

    def test_patch(self):
        golden = {'mt7981_rom_patch.bin': 1, 'mt7986_rom_patch.bin': 1,
                  'mt7916_rom_patch.bin': 1, 'mt7915_rom_patch.bin': 2}
        for p in sorted(FW.glob('mt79*_rom_patch.bin')):
            with self.subTest(blob=p.name):
                info = parse(p, REPO / 'extracted' / 'test_patch')
                self.assertEqual(info['platform'], 'ALPS')
                self.assertEqual(info['n_region'], golden[p.name])
                for sec in info['sections']:
                    self.assertEqual(sec['type'], '0x30002')
                    self.assertEqual(sec['enc_type'], 0)  # plaintext (F4)


if __name__ == '__main__':
    unittest.main(verbosity=2)