import json

from dvc.cli import main


def test_metrics_diff_simple(tmp_dir, scm, dvc, run_copy_metrics):
    def _gen(val):
        tmp_dir.gen({"m_temp.yaml": str(val)})
        run_copy_metrics("m_temp.yaml", "m.yaml", metrics=["m.yaml"])
        dvc.scm.commit(str(val))

    _gen(1)
    _gen(2)
    _gen(3)

    expected = {"m.yaml": {"": {"old": 1, "new": 3, "diff": 2}}}

    assert dvc.metrics.diff(a_rev="HEAD~2") == expected


def test_metrics_diff_yaml(tmp_dir, scm, dvc, run_copy_metrics):
    def _gen(val):
        metrics = {"a": {"b": {"c": val, "d": 1, "e": str(val)}}}
        (tmp_dir / "m_temp.yaml").dump(metrics)
        run_copy_metrics(
            "m_temp.yaml", "m.yaml", metrics=["m.yaml"], commit=str(val)
        )

    _gen(1)
    _gen(2)
    _gen(3)

    expected = {"m.yaml": {"a.b.c": {"old": 1, "new": 3, "diff": 2}}}

    assert dvc.metrics.diff(a_rev="HEAD~2") == expected


def test_metrics_diff_json(tmp_dir, scm, dvc, run_copy_metrics):
    def _gen(val):
        metrics = {"a": {"b": {"c": val, "d": 1, "e": str(val)}}}
        (tmp_dir / "m_temp.json").dump(metrics)
        run_copy_metrics(
            "m_temp.json", "m.json", metrics=["m.json"], commit=str(val)
        )

    _gen(1)
    _gen(2)
    _gen(3)

    expected = {"m.json": {"a.b.c": {"old": 1, "new": 3, "diff": 2}}}
    assert dvc.metrics.diff(a_rev="HEAD~2") == expected


def test_metrics_diff_json_unchanged(tmp_dir, scm, dvc, run_copy_metrics):
    def _gen(val):
        metrics = {"a": {"b": {"c": val, "d": 1, "e": str(val)}}}
        (tmp_dir / "m_temp.json").dump(metrics)
        run_copy_metrics(
            "m_temp.json", "m.json", metrics=["m.json"], commit=str(val)
        )

    _gen(1)
    _gen(2)
    _gen(1)

    assert dvc.metrics.diff(a_rev="HEAD~2") == {}


def test_metrics_diff_broken_json(tmp_dir, scm, dvc, run_copy_metrics):
    metrics = {"a": {"b": {"c": 1, "d": 1, "e": "3"}}}
    (tmp_dir / "m_temp.json").dump(metrics)
    run_copy_metrics(
        "m_temp.json",
        "m.json",
        metrics_no_cache=["m.json"],
        commit="add metrics",
    )

    (tmp_dir / "m.json").write_text(json.dumps(metrics) + "ma\nlformed\n")

    assert dvc.metrics.diff() == {
        "m.json": {
            "a.b.c": {"old": 1, "new": None},
            "a.b.d": {"old": 1, "new": None},
        }
    }


def test_metrics_diff_no_metrics(tmp_dir, scm, dvc):
    tmp_dir.scm_gen({"foo": "foo"}, commit="add foo")
    assert dvc.metrics.diff(a_rev="HEAD~1") == {}


def test_metrics_diff_new_metric(tmp_dir, scm, dvc, run_copy_metrics):
    metrics = {"a": {"b": {"c": 1, "d": 1, "e": "3"}}}
    (tmp_dir / "m_temp.json").dump(metrics)
    run_copy_metrics("m_temp.json", "m.json", metrics_no_cache=["m.json"])

    assert dvc.metrics.diff() == {
        "m.json": {
            "a.b.c": {"old": None, "new": 1},
            "a.b.d": {"old": None, "new": 1},
        }
    }


def test_metrics_diff_deleted_metric(tmp_dir, scm, dvc, run_copy_metrics):
    metrics = {"a": {"b": {"c": 1, "d": 1, "e": "3"}}}
    (tmp_dir / "m_temp.json").dump(metrics)
    run_copy_metrics(
        "m_temp.json",
        "m.json",
        metrics_no_cache=["m.json"],
        commit="add metrics",
    )

    (tmp_dir / "m.json").unlink()

    assert dvc.metrics.diff() == {
        "m.json": {
            "a.b.c": {"old": 1, "new": None},
            "a.b.d": {"old": 1, "new": None},
        }
    }


def test_metrics_diff_with_unchanged(tmp_dir, scm, dvc, run_copy_metrics):
    tmp_dir.gen("metrics_temp.yaml", "foo: 1\nxyz: 10")
    run_copy_metrics(
        "metrics_temp.yaml",
        "metrics.yaml",
        metrics_no_cache=["metrics.yaml"],
        commit="1",
    )

    tmp_dir.scm_gen("metrics.yaml", "foo: 2\nxyz: 10", commit="2")
    tmp_dir.scm_gen("metrics.yaml", "foo: 3\nxyz: 10", commit="3")

    assert dvc.metrics.diff(a_rev="HEAD~2", all=True) == {
        "metrics.yaml": {
            "foo": {"old": 1, "new": 3, "diff": 2},
            "xyz": {"old": 10, "new": 10, "diff": 0},
        }
    }


def test_no_commits(tmp_dir):
    from scmrepo.git import Git

    from dvc.repo import Repo

    git = Git.init(tmp_dir.fs_path)
    assert git.no_commits

    assert Repo.init().metrics.diff() == {}


def test_metrics_diff_dirty(tmp_dir, scm, dvc, run_copy_metrics):
    def _gen(val):
        tmp_dir.gen({"m_temp.yaml": str(val)})
        run_copy_metrics("m_temp.yaml", "m.yaml", metrics=["m.yaml"])
        dvc.scm.commit(str(val))

    _gen(1)
    _gen(2)
    _gen(3)

    tmp_dir.gen({"m.yaml": "4"})

    expected = {"m.yaml": {"": {"old": 3, "new": 4, "diff": 1}}}

    assert dvc.metrics.diff() == expected


def test_metrics_diff_cli(tmp_dir, scm, dvc, run_copy_metrics, caplog, capsys):
    def _gen(val):
        tmp_dir.gen({"m_temp.yaml": f"foo: {val}"})
        run_copy_metrics("m_temp.yaml", "m.yaml", metrics=["m.yaml"])
        dvc.scm.commit(str(val))

    _gen(1.23456789)
    _gen(2.34567891011)
    _gen(3.45678910111213)

    caplog.clear()
    capsys.readouterr()  # clearing the buffer
    assert main(["metrics", "diff", "HEAD~2"]) == 0

    captured = capsys.readouterr()

    assert captured.out == (
        "Path    Metric    HEAD~2    workspace    Change\n"
        "m.yaml  foo       1.23457   3.45679      2.22222\n"
    )


def test_metrics_diff_non_metrics(tmp_dir, scm, dvc):
    def _gen(val):
        tmp_dir.scm_gen({"some_file.yaml": f"foo: {val}"}, commit=str(val))

    _gen(1)
    _gen(2)
    _gen(3)

    result = dvc.metrics.diff(targets=["some_file.yaml"], a_rev="HEAD~2")
    assert result == {
        "some_file.yaml": {"foo": {"old": 1, "new": 3, "diff": 2}}
    }