from __future__ import annotations

from collections.abc import Callable
from dataclasses import replace

import pytest

from mdpolish._artifact_replay import (
    ReplayChange,
    ReplayComponent,
    ReplayError,
    replay_change_chain,
)
from mdpolish.models import markdown_sha256


def change(
    *,
    component_position: int,
    before_text: str,
    after_text: str,
    start: int,
    end: int,
    before_sha256: str,
    after_sha256: str,
    proposal_index: int = 0,
    edit_index: int = 0,
) -> ReplayChange:
    return ReplayChange(
        component_id=f"test.{component_position}",
        component_version="1.0.0",
        component_position=component_position,
        proposal_component_position=component_position,
        proposal_snapshot_sha256=before_sha256,
        proposal_index=proposal_index,
        edit_index=edit_index,
        start=start,
        end=end,
        before=before_text,
        after=after_text,
        before_sha256=before_sha256,
        after_sha256=after_sha256,
    )


def test_replay_builds_zero_change_stages_and_utf16_editor_ranges() -> None:
    original = "\ufeff😀 old\r\nCafe\u0301"
    final = "\ufeff😀 new\r\nCafe\u0301"
    input_hash = markdown_sha256(original)
    final_hash = markdown_sha256(final)
    recorded = change(
        component_position=0,
        before_text="old",
        after_text="new",
        start=3,
        end=6,
        before_sha256=input_hash,
        after_sha256=final_hash,
    )

    replayed = replay_change_chain(
        input_markdown=original,
        input_sha256=input_hash,
        components=(ReplayComponent("test.0", "1.0.0"), ReplayComponent("test.1", "1.0.0")),
        changes=(recorded,),
        current_sha256=final_hash,
        current_markdown=final,
        include_zero_change_stages=True,
    )

    assert replayed.current_markdown == final
    assert len(replayed.stages) == 2
    assert replayed.stages[1].before_markdown == final
    assert replayed.stages[1].after_markdown == final
    assert replayed.stages[1].changes == ()
    assert (replayed.changes[0].line, replayed.changes[0].column) == (1, 4)
    assert (replayed.changes[0].editor_start, replayed.changes[0].editor_end) == (4, 7)


def test_replay_uses_full_descending_application_key_not_record_order() -> None:
    original = "abcd"
    final = "aXXcYY"
    input_hash = markdown_sha256(original)
    final_hash = markdown_sha256(final)
    right = change(
        component_position=0,
        before_text="d",
        after_text="YY",
        start=3,
        end=4,
        before_sha256=input_hash,
        after_sha256=final_hash,
        proposal_index=1,
    )
    left = change(
        component_position=0,
        before_text="b",
        after_text="XX",
        start=1,
        end=2,
        before_sha256=input_hash,
        after_sha256=final_hash,
    )

    replayed = replay_change_chain(
        input_markdown=original,
        input_sha256=input_hash,
        components=(ReplayComponent("test.0", "1.0.0"),),
        changes=(right, left),
        current_sha256=final_hash,
        current_markdown=final,
        include_zero_change_stages=True,
    )

    assert replayed.current_markdown == final


@pytest.mark.parametrize(
    ("mutate", "message"),
    [
        (lambda item: replace(item, component_position=2), "component position"),
        (lambda item: replace(item, proposal_component_position=1), "proposal reference"),
        (lambda item: replace(item, before="bad"), "recorded snapshot"),
        (lambda item: replace(item, after_sha256="0" * 64), "batch hash"),
    ],
)
def test_replay_rejects_untrusted_change_chains(
    mutate: Callable[[ReplayChange], ReplayChange], message: str
) -> None:
    original = "old"
    final = "new"
    input_hash = markdown_sha256(original)
    final_hash = markdown_sha256(final)
    valid = change(
        component_position=0,
        before_text="old",
        after_text="new",
        start=0,
        end=3,
        before_sha256=input_hash,
        after_sha256=final_hash,
    )
    tampered = mutate(valid)

    with pytest.raises(ReplayError, match=message):
        replay_change_chain(
            input_markdown=original,
            input_sha256=input_hash,
            components=(ReplayComponent("test.0", "1.0.0"),),
            changes=(tampered,),
            current_sha256=final_hash,
            current_markdown=final,
            include_zero_change_stages=True,
        )


def test_replay_rejects_conflicting_ranges() -> None:
    original = "abc"
    input_hash = markdown_sha256(original)
    first = change(
        component_position=0,
        before_text="ab",
        after_text="x",
        start=0,
        end=2,
        before_sha256=input_hash,
        after_sha256="0" * 64,
    )
    second = change(
        component_position=0,
        before_text="bc",
        after_text="y",
        start=1,
        end=3,
        before_sha256=input_hash,
        after_sha256="0" * 64,
        proposal_index=1,
    )

    with pytest.raises(ReplayError, match="conflicting"):
        replay_change_chain(
            input_markdown=original,
            input_sha256=input_hash,
            components=(ReplayComponent("test.0", "1.0.0"),),
            changes=(first, second),
            current_sha256=input_hash,
            current_markdown=None,
            include_zero_change_stages=False,
        )