import pytest
from jaydiff.merge import merge_add, merge_delete, merge_update, merge_full

# ── merge_* ───────────────────────────────────────────────────────────────

class TestJayMerge:
    def test_merge_add_to_empty(self):
        assert merge_add({}, {'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}}

    def test_merge_add_new_key(self):
        assert merge_add({'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}},
                             {'d': 'icecream'}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}, 'd': 'icecream'}

    def test_merge_add_existing_unchanged(self):
        assert merge_add({'a': 'hamburger', 'b': 'fries', 'c': {'f': 'coffee'}, 'd': 'icecream'},
                             {'d': 'icecream'}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': {'f': 'coffee'}, 'd': 'icecream'}

    def test_merge_delete_top_key(self):
        assert merge_delete({'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}, 'd': 'icecream'},
                                {'d': 'icecream'}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}}

    def test_merge_delete_nested_key(self):
        assert merge_delete({'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}},
                                {'c': {'f': 'coffee'}}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke'}}

    def test_merge_delete_nested_leaves_sibling(self):
        assert merge_delete({'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}},
                                {'c': {'e': 'coke'}}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': {'f': 'coffee'}}


class TestJayMergeFull:
    def test_passthrough_when_old_empty(self):
        assert merge_full({}, {'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}}

    def test_empty_diff_unchanged(self):
        assert merge_full({'a': 'hamburger', 'b': 'fries', 'c': 'coke'}, {}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': 'coke'}

    def test_update(self):
        assert merge_full({'a': 'hamburger', 'b': 'fries', 'c': 'coke'}, {'update': {'c': 'pepsi'}}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': 'pepsi'}

    def test_update_add(self):
        assert merge_full({'a': 'hamburger', 'b': 'fries', 'c': 'pepsi'}, {'update_add': {'c': 'coke'}}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': 'coke'}

    def test_delete(self):
        assert merge_full({'a': 'hamburger', 'b': 'fries', 'c': 'pepsi', 'd': 'icecream'},
                              {'delete': {'d': 'icecream'}}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': 'pepsi'}

    def test_add_delete_update_combined(self):
        assert merge_full({'a': 'hamburger', 'b': 'fries', 'c': 'pepsi'},
                              {'add': {'d': 'icecream'}, 'delete': {'b': 'fries'}, 'update': {'c': 'coke'}}) \
            == {'a': 'hamburger', 'd': 'icecream', 'c': 'coke'}

    def test_nested_update_and_delete(self):
        assert merge_full({'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}},
                              {'delete': {'a': 'hamburger', 'b': 'fries', 'c': {'f': 'coffee'}},
                               'update': {'c': {'e': 'pepsi'}}}) \
            == {'c': {'e': 'pepsi'}}

    def test_update_add_new_subkey(self):
        assert merge_full({'a': 'hamburger', 'b': 'fries', 'c': {'e': 'coke', 'f': 'coffee'}},
                              {'update_add': {'c': {'e': 'pepsi', 'h': 'cake'}}}) \
            == {'a': 'hamburger', 'b': 'fries', 'c': {'e': 'pepsi', 'f': 'coffee', 'h': 'cake'}}

    def test_real_world_snapshot_update(self):
        old = {'charging': {
            'batteryStatus': {'value': {'carCapturedTimestamp': '2024-10-19T05:34:34Z', 'cruisingRangeElectric_km': 192}},
            'chargingStatus': {'value': {'carCapturedTimestamp': '2024-10-19T05:34:34Z'}},
            'chargingSettings': {'value': {'carCapturedTimestamp': '2024-10-19T05:34:30Z'}},
            'plugStatus': {'value': {'carCapturedTimestamp': '2024-10-19T05:34:29Z'}}}}
        update = {'charging': {
            'batteryStatus': {'value': {'carCapturedTimestamp': '2024-10-19T05:35:46Z', 'cruisingRangeElectric_km': 191}},
            'chargingStatus': {'value': {'carCapturedTimestamp': '2024-10-19T05:35:46Z'}}}}
        add = {'charging': {'batteryStatus': {'value': {'currentSOC_pct': 55}}},
               'fuelStatus': {'rangeStatus': {'value': {'primaryEngine': {'currentSOC_pct': 55}}}},
               'measurements': {'fuelLevelStatus': {'value': {'currentSOC_pct': 55}}}}
        delete = {'charging': {
            'chargingSettings': {'value': {'carCapturedTimestamp': '2024-10-19T05:34:30Z'}},
            'plugStatus': {'value': {'carCapturedTimestamp': '2024-10-19T05:34:29Z'}}}}
        result = merge_full(old, {'update': update, 'add': add, 'delete': delete})
        assert result == old