"""Unit tests for canonical flow files (export.py). No DB or LFX needed."""

import json

from app.flows import export


def test_filename_stem_keeps_original_names():
    assert export.filename_stem("simple_rule") == "simple_rule"
    assert export.filename_stem("test_flow") == "test_flow"
    assert export.filename_stem("Gehaltserhöhung") == "Gehaltserhöhung"
    assert export.filename_stem("Dachsanierung 200k") == "Dachsanierung 200k"
    assert export.filename_stem("  A/B\\C  ") == "A-B-C"
    assert export.filename_stem('a:b*c?d"e<f>g|h') == "a-b-c-d-e-f-g-h"
    assert export.filename_stem("trailing...") == "trailing"
    assert export.filename_stem("") == "flow"


def test_canonical_bytes_stable_under_key_reorder():
    doc = {"name": "x", "data": {"nodes": [], "edges": []}, "tags": ["b", "a"]}
    shuffled = {"tags": ["b", "a"], "data": {"edges": [], "nodes": []}, "name": "x"}
    assert export.canonical_bytes(shuffled) == export.canonical_bytes(doc)
    assert export.content_hash(doc) == export.content_hash(shuffled)


def test_write_and_read_roundtrip_is_byte_stable(tmp_path):
    doc = {"name": "My Flow", "data": {"nodes": [], "edges": []}}
    path = export.write_flow_file(tmp_path, doc)
    assert path == tmp_path / "My Flow.json"
    assert json.loads(path.read_text()) == doc
    # Rewriting identical content is byte-identical (no phantom git diffs).
    before = path.read_bytes()
    export.write_flow_file(tmp_path, doc)
    assert path.read_bytes() == before


def test_iter_flow_files_only_top_level_json(tmp_path):
    (tmp_path / "a.json").write_text("{}")
    (tmp_path / "b.txt").write_text("{}")
    sub = tmp_path / "sub"
    sub.mkdir()
    (sub / "c.json").write_text("{}")
    assert export.iter_flow_files(tmp_path) == [tmp_path / "a.json"]


def test_find_reuse_path_matches_identical_content_first(tmp_path):
    doc = {"name": "Simple Rule", "data": {"nodes": [], "edges": []}}
    other = tmp_path / "other-name.json"
    other.write_text(export.canonical_bytes(doc).decode())
    path, identical = export.find_reuse_path(tmp_path, dict(doc))
    assert (path, identical) == (other, True)


def test_find_reuse_path_matches_same_name(tmp_path):
    old = {"name": "Simple Rule", "data": {"nodes": [], "edges": []}, "extra": 1}
    (tmp_path / "simple_rule.json").write_text(json.dumps(old))
    new = {"name": "Simple Rule", "data": {"nodes": [], "edges": []}}
    path, identical = export.find_reuse_path(tmp_path, new)
    assert (path, identical) == (tmp_path / "simple_rule.json", False)


def test_find_reuse_path_no_match_and_missing_dir(tmp_path):
    (tmp_path / "a.json").write_text(json.dumps({"name": "Other"}))
    assert export.find_reuse_path(tmp_path, {"name": "Neu"}) == (None, False)
    assert export.find_reuse_path(tmp_path / "gibts-nicht", {"name": "Neu"}) == (None, False)


def test_find_reuse_path_skips_unreadable_files(tmp_path):
    (tmp_path / "kaputt.json").write_text("{kein json")
    assert export.find_reuse_path(tmp_path, {"name": "Neu"}) == (None, False)


def test_write_flow_file_is_world_readable(tmp_path):
    import os
    import stat

    doc = {"name": "Lesbar", "data": {"nodes": [], "edges": []}}
    path = export.write_flow_file(tmp_path, doc)
    mode = stat.S_IMODE(os.stat(path).st_mode)
    # Read bits for user/group/other (mkstemp defaults to 0o600; on Windows
    # chmod maps to 0o666, so only assert the read bits, not the exact mode).
    assert mode & 0o444 == 0o444, f"expected world-readable, got {oct(mode)}"