#Requires -Version 5.1
<#
.SYNOPSIS
    Bookworm Smart Assistant v6.6-rc2 Agent 信任边界体系一键回滚
.DESCRIPTION
    代号: v6.6-rc2-20260422-1859
    按分级回滚 P3 → P2 → P1 → P0 各阶段，最终重签 HMAC 完整性链。
    数据文件 (logs/agent-returns.jsonl, state/claim-mismatches.jsonl) 不删除，保留审计。

    Linux/WSL 用户: 逐步等价 bash 版待 port。核心动作参见每步注释的 bash 等价。
.PARAMETER Scope
    回滚范围:
      all       -- 全量回滚到 v6.5.1 (默认)
      P3-only   -- 仅移除 agent-claim-cross-verify.js
      P2-down   -- 移除 P3 + Dashboard + 诚实度统计
      P1-down   -- 移除 P3 + P2 + verifier + snapshot-taker (保留 P0 观察)
.PARAMETER DryRun
    预演模式: 只打印 "将移除 / 将恢复" 提示, 不实际执行任何删除/写入,
    不调用 integrity-check --generate, 不追加 evolution-log.
    真回滚前强烈建议先跑一次 -DryRun 审视预期动作。
.EXAMPLE
    pwsh .\rollback-v6.6-rc2.ps1
    pwsh .\rollback-v6.6-rc2.ps1 -Scope P3-only
    pwsh .\rollback-v6.6-rc2.ps1 -DryRun              # 预演全量回滚
    pwsh .\rollback-v6.6-rc2.ps1 -Scope P1-down -DryRun
.NOTES
    每一步都是幂等的 (Test-Path 先查再删)。多次运行无副作用。
    成功执行后 evolution-log.jsonl 追加一条 rollback 事件。
#>
param(
    [ValidateSet('all','P3-only','P2-down','P1-down')]
    [string]$Scope = 'all',
    [switch]$DryRun
)

$ErrorActionPreference = 'Stop'
$CLAUDE_ROOT = Join-Path $env:USERPROFILE '.claude'
$HOOKS       = Join-Path $CLAUDE_ROOT 'hooks'
$SCRIPTS     = Join-Path $CLAUDE_ROOT 'scripts'
$STATE       = Join-Path $CLAUDE_ROOT 'state'
$CONFIG      = Join-Path $CLAUDE_ROOT 'config'
$CONSTITUTION = Join-Path $CLAUDE_ROOT 'constitution\anti-arrogance.md'
$SETTINGS    = Join-Path $CLAUDE_ROOT 'settings.json'
$EVOLUTION   = Join-Path $CLAUDE_ROOT 'debug\evolution-log.jsonl'
$CODE        = 'v6.6-rc2-20260422-1859'

function Write-Step { param([string]$Msg) Write-Host "[rollback] $Msg" -ForegroundColor Cyan }
function Remove-IfExists {
    param([string]$Path, [string]$Tag)
    if (Test-Path -LiteralPath $Path) {
        if ($script:DryRun) {
            Write-Step "$Tag [DRY-RUN] 将移除: $Path"
        } else {
            Remove-Item -LiteralPath $Path -Force
            Write-Step "$Tag 已移除: $Path"
        }
    } else {
        Write-Step "$Tag 不存在 (跳过): $Path"
    }
}
function Restore-LatestBak {
    param([string]$Target, [string]$BakPrefix, [string]$Tag)
    $dir  = Split-Path $Target -Parent
    $name = Split-Path $Target -Leaf
    $pattern = "$name.$BakPrefix*"
    $bak = Get-ChildItem -LiteralPath $dir -Filter $pattern -ErrorAction SilentlyContinue |
           Sort-Object LastWriteTime -Descending | Select-Object -First 1
    if ($bak) {
        if ($script:DryRun) {
            Write-Step "$Tag [DRY-RUN] 将从 $($bak.Name) 恢复"
        } else {
            Copy-Item -LiteralPath $bak.FullName -Destination $Target -Force
            Write-Step "$Tag 已从 $($bak.Name) 恢复"
        }
    } else {
        Write-Step "$Tag 未找到 $pattern 备份 (可能未曾应用该阶段)"
    }
}

# Scope → 各阶段是否执行 (PowerShell 无 goto, 用标志位分级控制流)
$runP3 = $true
$runP2 = ($Scope -ne 'P3-only')
$runP1 = ($Scope -notin @('P3-only','P2-down'))
$runP0 = ($Scope -eq 'all')

$modeTag = if ($DryRun) { ' [DRY-RUN 预演模式]' } else { '' }
Write-Host "============================================================" -ForegroundColor Yellow
Write-Host " Bookworm v6.6-rc2 回滚$modeTag · Scope=$Scope" -ForegroundColor Yellow
Write-Host " 阶段执行: P3=$runP3  P2=$runP2  P1=$runP1  P0=$runP0" -ForegroundColor Yellow
Write-Host "============================================================" -ForegroundColor Yellow

# ------------------------------------------------------------------
# P3 层 (T12)
# ------------------------------------------------------------------
if ($runP3) {
    Write-Step '--- Phase P3 ---'
    # bash: rm -f $CLAUDE_ROOT/hooks/agent-claim-cross-verify.js
    Remove-IfExists (Join-Path $HOOKS 'agent-claim-cross-verify.js') '[T12]'
    Remove-IfExists (Join-Path $CONFIG 'cross-verify-budget.json')    '[T12]'
}

# ------------------------------------------------------------------
# P2 层 (T09, T10, T11)
# ------------------------------------------------------------------
if ($runP2) {
    Write-Step '--- Phase P2 ---'
    Remove-IfExists (Join-Path $HOOKS 'agent-honesty-stats.js')             '[T09]'
    Remove-IfExists (Join-Path $CLAUDE_ROOT 'dashboard\agent-honesty.html') '[T11]'
    # T10 对 daily-health-snapshot.js 是扩展, 走 sentinel 撤销 (待 T10 补丁填充 undo 段)
    Write-Step '[T10] TODO: 调用 scripts/patches/v6.6-rc2-04-health-snapshot-ext.js --undo (T10 落地后填充)'
    Remove-IfExists (Join-Path $CONFIG 'health-weights.json')               '[T09/T10 参数]'
}

# ------------------------------------------------------------------
# P1 层 (T05, T06, T07, T08)
# ------------------------------------------------------------------
if ($runP1) {
    Write-Step '--- Phase P1 ---'
    Remove-IfExists (Join-Path $HOOKS 'agent-claim-verifier.js')   '[T07]'
    Remove-IfExists (Join-Path $HOOKS 'agent-snapshot-taker.js')   '[T06]'
    # T05 对 subagent-route-injector.js 追加契约模板, 回滚到 P0 版本
    Restore-LatestBak (Join-Path $HOOKS 'subagent-route-injector.js') 'bak.v6.6-rc2-03-claim-contract' '[T05]'
}

# ------------------------------------------------------------------
# P0 层 (T02, T03, T04)
# ------------------------------------------------------------------
if ($runP0) {
    Write-Step '--- Phase P0 ---'
    # T02: 卸载 agent-claim-observer.js + 撤销 SubagentStop 挂载
    Remove-IfExists (Join-Path $HOOKS 'agent-claim-observer.js') '[T02 hook]'
    Restore-LatestBak $SETTINGS 'bak.v6.6-rc2-01-register-subagent-stop' '[T02 settings]'

    # T03: subagent-route-injector 恢复 v5.2 版本 (P0 traceId 注入)
    Restore-LatestBak (Join-Path $HOOKS 'subagent-route-injector.js') 'bak.v6.6-rc2-02-inject-traceid' '[T03]'

    # T04: 宪法追加段删除 + log-rotator 配置回退
    Write-Step '[T04] 宪法 sentinel 段删除:'
    if (Test-Path -LiteralPath $CONSTITUTION) {
        $text = Get-Content -LiteralPath $CONSTITUTION -Raw -Encoding UTF8
        $pattern = '(?s)<!-- closure-loop:agent-trust:v1 -->.*?<!-- /closure-loop:agent-trust:v1 -->'
        if ($text -match $pattern) {
            if ($DryRun) {
                Write-Step '  [DRY-RUN] 将移除 sentinel 段 (原子写)'
            } else {
                $cleaned = [regex]::Replace($text, $pattern, '').TrimEnd() + "`n"
                # 原子写
                $tmp = "$CONSTITUTION.tmp.rollback.$PID"
                [IO.File]::WriteAllText($tmp, $cleaned, [Text.UTF8Encoding]::new($false))
                Move-Item -LiteralPath $tmp -Destination $CONSTITUTION -Force
                Write-Step '  sentinel 段已移除 (原子写)'
            }
        } else {
            Write-Step '  sentinel 段不存在 (跳过)'
        }
    }
    Restore-LatestBak (Join-Path $HOOKS 'log-rotator.js') 'bak.v6.6-rc2-04-log-rotator' '[T04]'

    # 数据文件 保留审计 (原 prompt 第 8 条: 保留 logs/ 和 state/ 数据)
    Write-Step 'logs/agent-returns.jsonl 和 state/claim-mismatches.jsonl 按审计要求保留'
}

# ------------------------------------------------------------------
# 最后: HMAC 完整性链重签 (所有 scope 都执行)
# ------------------------------------------------------------------
Write-Step '--- Reseal HMAC ---'
if ($DryRun) {
    Write-Step '[DRY-RUN] 将调用: node hooks/integrity-check.js --generate'
    Write-Step '[DRY-RUN] 将追加 evolution-log.jsonl rollback 事件'
} else {
    # bash: node $CLAUDE_ROOT/hooks/integrity-check.js --generate
    & node (Join-Path $HOOKS 'integrity-check.js') --generate
    if ($LASTEXITCODE -ne 0) {
        throw "integrity-check --generate 失败, exit=$LASTEXITCODE"
    }

    # 追加 evolution-log
    try {
        $entry = @{
            ts        = (Get-Date).ToString('o')
            event     = 'rollback'
            code      = $CODE
            scope     = $Scope
            operator  = "$env:USERNAME@$env:COMPUTERNAME"
        } | ConvertTo-Json -Compress
        Add-Content -LiteralPath $EVOLUTION -Value $entry -Encoding UTF8
        Write-Step 'evolution-log.jsonl 已追加 rollback 事件'
    } catch {
        Write-Step "evolution-log 追加失败 (非阻塞): $_"
    }
}

$finishTag = if ($DryRun) { '预演完成 (未实际变更)' } else { '回滚完成' }
Write-Host ''
Write-Host '============================================================' -ForegroundColor Green
Write-Host " $finishTag · Scope=$Scope" -ForegroundColor Green
if (-not $DryRun) {
    Write-Host " 下一步验证: node $HOOKS\integrity-check.js (PostToolUse 模拟)" -ForegroundColor Green
}
Write-Host '============================================================' -ForegroundColor Green