"""Tests for scripts/merge_prefs.py"""
import shutil
from pathlib import Path
from xml.etree import ElementTree as ET

import pytest

import merge_prefs

FIXTURES = Path(__file__).parent / "fixtures"


def _parse(path: Path) -> ET.Element:
    return ET.parse(path).getroot()


def _attr(root: ET.Element, *id_path: str) -> dict:
    """Walk id_path through nested <group id=...> elements, return attribs."""
    node = root
    for id_val in id_path:
        node = next(
            (c for c in node if c.get("id") == id_val), None
        )
        assert node is not None, f"Node with id={id_val!r} not found"
    return dict(node.attrib)


# ── merge into existing prefs ─────────────────────────────────────────────────

def test_merge_changes_patched_attributes(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-fresh.xml", prefs)
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cc")
    root = _parse(prefs)
    assert _attr(root, "options", "scroll")["mousewheel-zoom"] == "false"
    assert _attr(root, "options", "zoom")["mousewheel-zoom-ctrl"] == "true"
    assert _attr(root, "tools", "nodes")["square-handles"] == "true"


def test_merge_creates_missing_nodes(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-fresh.xml", prefs)
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cc")
    root = _parse(prefs)
    assert _attr(root, "options", "new-group")["new-attr"] == "new-value"


def test_merge_preserves_user_nodes(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-user-custom.xml", prefs)
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cc")
    root = _parse(prefs)
    assert _attr(root, "options", "user-custom-setting")["my-value"] == "keep-this"
    assert _attr(root, "tools", "user-tool-pref")["color"] == "#ff0000"


def test_merge_preserves_existing_unknown_attributes(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-user-custom.xml", prefs)
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cc")
    root = _parse(prefs)
    assert _attr(root, "tools", "nodes").get("user-pref") == "preserved"


def test_merge_is_idempotent(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-fresh.xml", prefs)
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cc")
    content_after_first = prefs.read_text()
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cc")
    content_after_second = prefs.read_text()
    assert content_after_first == content_after_second


# ── lenient: no prefs file ────────────────────────────────────────────────────

def test_merge_creates_prefs_when_missing(tmp_path):
    prefs = tmp_path / "inkscape" / "preferences.xml"
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cc")
    assert prefs.exists()
    root = _parse(prefs)
    assert _attr(root, "options", "scroll")["mousewheel-zoom"] == "false"


def test_merge_creates_parent_dirs_when_missing(tmp_path):
    prefs = tmp_path / "deep" / "nested" / "dir" / "preferences.xml"
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cc")
    assert prefs.exists()


# ── preset overrides ──────────────────────────────────────────────────────────

def test_preset_cc_sets_keys_file(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-fresh.xml", prefs)
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cc")
    root = _parse(prefs)
    assert _attr(root, "options", "keyboard")["file"] == "illustrator-cc"


def test_preset_cs6_sets_keys_file(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-fresh.xml", prefs)
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cs6")
    root = _parse(prefs)
    assert _attr(root, "options", "keyboard")["file"] == "illustrator-cs6"


def test_preset_cc_sets_px_units(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-fresh.xml", prefs)
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cc")
    root = _parse(prefs)
    assert _attr(root, "options", "units")["doc"] == "px"


def test_preset_cs6_sets_pt_units(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-fresh.xml", prefs)
    merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cs6")
    root = _parse(prefs)
    assert _attr(root, "options", "units")["doc"] == "pt"


# ── error handling ────────────────────────────────────────────────────────────

def test_merge_raises_on_malformed_prefs(tmp_path):
    prefs = tmp_path / "preferences.xml"
    prefs.write_text("this is not xml")
    with pytest.raises(ET.ParseError):
        merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "cc")


def test_merge_raises_on_missing_patch(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-fresh.xml", prefs)
    with pytest.raises(FileNotFoundError):
        merge_prefs.merge(prefs, tmp_path / "nonexistent-patch.xml", "cc")


def test_merge_raises_on_malformed_patch(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-fresh.xml", prefs)
    bad_patch = tmp_path / "bad-patch.xml"
    bad_patch.write_text("not xml at all")
    with pytest.raises(ET.ParseError):
        merge_prefs.merge(prefs, bad_patch, "cc")


def test_merge_raises_on_invalid_preset(tmp_path):
    prefs = tmp_path / "preferences.xml"
    shutil.copy(FIXTURES / "prefs-fresh.xml", prefs)
    with pytest.raises(ValueError, match="Unknown preset"):
        merge_prefs.merge(prefs, FIXTURES / "patch-minimal.xml", "bad-preset")