"""Regression coverage for single-pass sidebar session partitioning."""

from __future__ import annotations

from pathlib import Path

ROOT = Path(__file__).resolve().parents[1]
SESSIONS_JS = (ROOT / "static" / "sessions.js").read_text(encoding="utf-8")


def _function_block(name: str) -> str:
    start = SESSIONS_JS.index(f"function {name}(")
    brace = SESSIONS_JS.index("{", start)
    depth = 0
    for idx in range(brace, len(SESSIONS_JS)):
        char = SESSIONS_JS[idx]
        if char == "{":
            depth += 1
        elif char == "}":
            depth -= 1
            if depth == 0:
                return SESSIONS_JS[start : idx + 1]
    raise AssertionError(f"unbalanced braces in {name}")


def _partition_block() -> str:
    return _function_block("_partitionSidebarSessionRows")


def test_render_uses_single_pass_partition_helper():
    render_body = _function_block("renderSessionListFromCache")

    assert "_partitionSidebarSessionRows(allMatched, activeSidForSidebar)" in render_body
    assert "_renderSidebarRowsFromRawSessions(sessionsRaw, [...referenceRaw, ..._scopedSidebarReferenceRows(isCliView, projectIdFor)])" in render_body
    assert "const renderedWebuiSessionCount=_serverWebuiSessionCount===null" in render_body
    assert "const renderedCliSessionCount=_serverCliSessionCount===null" in render_body
    assert "? _renderSidebarRowsFromRawSessions(webuiSessionsRaw, [...webuiReferenceRaw, ..._scopedSidebarReferenceRows(false, projectIdFor)]).length" in render_body
    assert "? _renderSidebarRowsFromRawSessions(cliSessionsRaw, [...cliReferenceRaw, ..._scopedSidebarReferenceRows(true, projectIdFor)]).length" in render_body
    assert ": null;" in render_body
    assert "null is a deliberate \"not computed\" sentinel" in render_body
    assert "const webuiSessionTabCount=_sessionSourceTabCount('webui', renderedWebuiSessionCount, renderedCliSessionCount);" in render_body
    assert "const cliSessionTabCount=_sessionSourceTabCount('cli', renderedWebuiSessionCount, renderedCliSessionCount);" in render_body
    assert "const count=filter==='cli'?cliSessionTabCount:webuiSessionTabCount;" in render_body
    assert "const count=filter==='cli'?renderedCliSessionCount:renderedWebuiSessionCount;" not in render_body
    assert "withMessages.filter(" not in render_body


def test_partition_helper_applies_message_source_project_and_archive_gates():
    block = _partition_block()

    assert "function _sidebarRowHasVisibleMessages(s, activeSidForSidebar)" in SESSIONS_JS
    assert "_sidebarRowHasVisibleMessages(s, activeSidForSidebar)" in block
    assert "if(_sessionSourceFilter==='cli' && !window._showCliSessions && cliSessionCount===0)" in block
    assert "const showCliOnly=_sessionSourceFilter==='cli';" in block
    assert "if(!_showArchived&&s.archived) continue;" in block
    assert "if(s.archived){" in block
    assert "const serverArchivedCount=showCliOnly?_archivedCliCount:_archivedWebuiCount;" in block
    assert "archivedCount: Math.max(showCliOnly ? cliArchivedCount : webuiArchivedCount, Number(serverArchivedCount||0))," in block
    assert "return {" in block
    assert "profileFiltered: showCliOnly ? cliProfileFiltered : webuiProfileFiltered," in block
    assert "sessionsRaw: showCliOnly ? cliSessionsRaw : webuiSessionsRaw," in block


def test_partition_helper_keeps_raw_source_counts_while_render_owns_visible_counts():
    render_body = _function_block("renderSessionListFromCache")

    assert "webuiSessionCount," not in _partition_block()
    assert "cliSessionCount," in _partition_block()
    assert "webuiReferenceRaw," in _partition_block()
    assert "cliReferenceRaw," in _partition_block()
    assert "webuiSessionsRaw," in _partition_block()
    assert "cliSessionsRaw," in _partition_block()
    assert "const renderedWebuiSessionCount=_serverWebuiSessionCount===null" in render_body
    assert "const renderedCliSessionCount=_serverCliSessionCount===null" in render_body
    assert "? _renderSidebarRowsFromRawSessions(webuiSessionsRaw, [...webuiReferenceRaw, ..._scopedSidebarReferenceRows(false, projectIdFor)]).length" in render_body
    assert "? _renderSidebarRowsFromRawSessions(cliSessionsRaw, [...cliReferenceRaw, ..._scopedSidebarReferenceRows(true, projectIdFor)]).length" in render_body
    assert "function _countRenderedSidebarRowsFromRawSessions" not in SESSIONS_JS
    assert "function _renderSidebarRowsFromRawSessions(sessionsRaw, referenceSessionsRaw){" in SESSIONS_JS
    assert "_attachChildSessionsToSidebarRows(_collapseSessionLineageForSidebar(sessionsRaw), sessionsRaw, referenceRows)" in SESSIONS_JS


def test_archive_load_more_uses_source_wide_loaded_count_and_hides_under_filters():
    render_body = _function_block("renderSessionListFromCache")

    assert "function _sessionArchivePagingFilterActive()" in SESSIONS_JS
    assert "const archivePagingFilterActive=_sessionArchivePagingFilterActive();" in render_body
    assert "if(_showArchived&&!archivePagingFilterActive){" in render_body
    assert "const loadedArchivedCount=sidebarRows.filter" in render_body
    assert "const archiveLoadCapReached=Number(_archivedRowsLoadedLimit||0)>=SESSION_ARCHIVED_MAX_LOADED_LIMIT;" in render_body
    assert "const remainingArchived=archiveLoadCapReached?0:Math.max(0, Number(activeArchivedTotal||0)-loadedArchivedCount);" in render_body
    assert "const remainingArchived=Math.max(0, Number(activeArchivedTotal||0)-loadedArchivedCount);" not in render_body
    assert "orderedSessions.filter(s=>s&&s.archived).length" not in render_body