#!/usr/bin/env python3
"""Materialize previously verified fixed Git archives for an isolated PDFium build."""
import hashlib
import json
from pathlib import Path, PurePosixPath
import tarfile

ROOT = Path(__file__).resolve().parents[2]


def sha(path):
    with path.open('rb') as stream: return hashlib.file_digest(stream,'sha256').hexdigest()


def main():
    reports=[ROOT/'tests/results/source-archives/pdfium-git/report.json',
             ROOT/'tests/results/source-archives/pdfium-gitlink/report.json']
    repositories=[]
    for path in reports:
        report=json.loads(path.read_text()); assert report['success']
        repositories.extend(report['repositories'])
    source=ROOT/'build-pdfium-intent/source'
    source.mkdir(parents=True,exist_ok=False)
    output=ROOT/'tests/results/pdfium-intent-build'; output.mkdir(parents=True,exist_ok=False)
    materialized=[]; links=[]; total=0; count=0
    for repository in repositories:
        archive=ROOT/repository['archive']; inventory=ROOT/repository['inventory']
        assert sha(archive)==repository['archiveSha256'] and sha(inventory)==repository['inventorySha256']
        expected={r['path']:r for line in inventory.open() if (r:=json.loads(line))['archived']}
        prefix='pdfium/'+('' if repository['path']=='.' else repository['path']+'/')
        found=set()
        with tarfile.open(archive) as stream:
            for member in stream:
                assert member.name.startswith(prefix)
                relative=member.name.removeprefix(prefix)
                if member.isdir(): continue
                assert relative in expected and relative not in found
                found.add(relative); row=expected[relative]
                name=PurePosixPath(member.name.removeprefix('pdfium/'))
                assert not name.is_absolute() and '..' not in name.parts and '\\' not in str(name)
                path=source/name; assert path.resolve().is_relative_to(source) and not path.exists()
                path.parent.mkdir(parents=True,exist_ok=True)
                if member.issym():
                    assert row['mode']=='120000' and member.linkname==row['linkTarget']
                    target=PurePosixPath(member.linkname)
                    assert not target.is_absolute() and (path.parent/target).resolve().is_relative_to(source)
                    assert hashlib.sha256(member.linkname.encode()).hexdigest()==row['sha256']
                    links.append((path,member.linkname))
                    continue
                assert member.isfile() and row['mode'] in ('100644','100755') and member.size==row['bytes']
                total+=member.size; count+=1
                assert member.size<=256*1024**2 and total<=2*1024**3 and count<=100000
                digest=hashlib.sha256()
                with stream.extractfile(member) as incoming, path.open('xb') as outgoing:
                    for chunk in iter(lambda:incoming.read(1024*1024),b''):
                        digest.update(chunk); outgoing.write(chunk)
                assert digest.hexdigest()==row['sha256']
                path.chmod(0o755 if row['mode']=='100755' else 0o644)
        assert found==expected.keys()
        materialized.append({k:repository[k] for k in ('path','revision','archive','archiveSha256','inventory','inventorySha256')})
    for path,target in links:
        assert (path.parent/target).resolve().is_file()
        path.symlink_to(target)
    record={'success':True,'preparerSha256':sha(Path(__file__)),'source':str(source.relative_to(ROOT)),
            'repositories':materialized,'regularFiles':count,'regularBytes':total,'symlinks':len(links),
            'sourceReports':{str(p.relative_to(ROOT)):sha(p) for p in reports},
            'scope':'Fixed sources materialized for a separate local build. No source hooks, downloads or build executed by this preparer. Production dependency remains unchanged.'}
    (output/'source-materialization.json').write_text(json.dumps(record,indent=2)+'\n')
    print(json.dumps({'repositories':len(materialized),'regularFiles':count,'regularBytes':total,'symlinks':len(links)}))


if __name__=='__main__':main()