<#
.SYNOPSIS
  Verify that a code-review report carries a line-coverage gate (fail-closed).

.DESCRIPTION
  Enforces the "three-piece suite" guarantee defined in project-review/SKILL.md
  Step 8.7: whole-project / feature review reports MUST contain a line coverage
  (xingfugai) field in their coverage section, and its value MUST be >= the
  configured target (default 95%).  A missing field means the review never ran
  coverage_tool(gate="both+line") (or forgot the three-piece data) and the
  report would otherwise look green with no line coverage.

  Scope handling: only whole-project and feature reviews are gated; other
  scopes (e.g. change-level) are skipped.

  Exit codes: 0 = line coverage present and >= target (or scope not gated);
  1 = blocking violation (missing line coverage or below target).

.PARAMETER Repo
  Repository root. Defaults to the current directory.

.PARAMETER Report
  Optional relative path (under docs/reviews/) to a specific report file.
  Defaults to the newest *.md report in docs/reviews/.

.PARAMETER Target
  Minimum line-coverage percentage. Default 95.

.EXAMPLE
  powershell -File verify-line-coverage.ps1 -Repo D:\AuraSpace
  powershell -File verify-line-coverage.ps1 -Repo D:\AuraSpace -Report full-project-review-2026-08-17-101500.md
#>
param(
    [string]$Repo = "",
    [string]$Report = "",
    [double]$Target = 95.0
)

$ErrorActionPreference = "Stop"

function Write-Step([string]$msg) { Write-Host "  $msg" -ForegroundColor DarkGray }
function Write-Ok([string]$msg)   { Write-Host "  [OK] $msg" -ForegroundColor Green }
function Write-Bad([string]$msg)  { Write-Host "  [!!] $msg" -ForegroundColor Red }
function Write-Warn([string]$msg) { Write-Host "  [!] $msg" -ForegroundColor Yellow }

# Resolve repo root ---------------------------------------------------------
if ([string]::IsNullOrWhiteSpace($Repo)) { $Repo = (Get-Location).Path }
$root = (Resolve-Path -LiteralPath $Repo).Path
$reviewsDir = Join-Path $root "docs\reviews"

Write-Host "verify-line-coverage: repo = $root (target $Target%)"
Write-Host ""

# Locate the report --------------------------------------------------------
$reportPath = ""
if (-not [string]::IsNullOrWhiteSpace($Report)) {
    $reportPath = Join-Path $reviewsDir $Report
    if (-not (Test-Path -LiteralPath $reportPath)) {
        Write-Bad "report not found: $reportPath"
        exit 1
    }
} else {
    if (-not (Test-Path -LiteralPath $reviewsDir)) {
        Write-Warn "docs/reviews/ does not exist - no report to verify"
        Write-Host "RESULT: PASS (no report)" -ForegroundColor Green
        exit 0
    }
    $reportPath = Get-ChildItem -LiteralPath $reviewsDir -File |
        Where-Object { $_.Extension -eq ".md" } |
        Sort-Object LastWriteTime -Descending |
        Select-Object -First 1 -ExpandProperty FullName
    if (-not $reportPath) {
        Write-Warn "no .md report in docs/reviews/ - nothing to verify"
        Write-Host "RESULT: PASS (no report)" -ForegroundColor Green
        exit 0
    }
}

Write-Step "checking report: $reportPath"

# Parse scope from header (line like: 档位：standard · 范围：whole-project · 基线：...)
$content = [System.IO.File]::ReadAllText($reportPath, [System.Text.Encoding]::UTF8)
$scope = ""
$scopeLine = ($content -split "`n" | Where-Object { $_ -match "范围" } | Select-Object -First 1)
if ($scopeLine -and $scopeLine -match "范围\**[:：]\s*([^\s·*]+)") {
    $scope = $Matches[1].Trim()
}

# Scope gate: only change-level reviews are skipped.  whole-project / feature
# AND any custom scope value (e.g. scope="evm") that still produced a coverage
# section must be checked for line coverage.
if ($scope -eq "change-level") {
    Write-Warn "scope = '$scope' is not gated on line coverage (change-level only)"
    Write-Host "RESULT: PASS (scope not gated)" -ForegroundColor Green
    exit 0
}
Write-Step "scope = '$scope' (gated)"

# Parse ## 覆盖度 section
$covSection = ""
$lines = $content -split "`r?`n"
for ($i = 0; $i -lt $lines.Count; $i++) {
    if ($lines[$i] -match "^##\s*\**覆盖度\**") {
        $j = $i + 1
        $buf = @()
        while ($j -lt $lines.Count -and -not ($lines[$j] -match "^##\s")) {
            $buf += $lines[$j]; $j++
        }
        $covSection = $buf -join "`n"
        break
    }
}
if (-not $covSection) {
    Write-Bad "no coverage section found - line coverage cannot be verified"
    exit 1
}

# Line-coverage field present?
$lineLine = ($covSection -split "`n" | Where-Object { $_ -match "行覆盖" } | Select-Object -First 1)
if (-not $lineLine) {
    Write-Bad "coverage section has NO line-coverage field - gate='both+line' was not run (or three-piece data missing)"
    Write-Step "coverage section:"
    foreach ($l in ($covSection -split "`n" | Where-Object { $_.Trim() })) { Write-Step "  $($l.Trim())" }
    exit 1
}

# "未执行" marker means gate never ran
if ($lineLine -match "未执行") {
    Write-Bad "line coverage = NOT RUN (gate='both+line' not run or three-piece data missing)"
    Write-Step $lineLine.Trim()
    exit 1
}

# Extract percentage (行覆盖：99.8% — 目标 95.0%（缺口 0 文件）✅)
if ($lineLine -match "行覆盖\**[:：]\s*([0-9.]+)\s*%") {
    $pct = [double]$Matches[1]
    if ($pct -lt $Target) {
        Write-Bad "line coverage $pct% < target $Target%"
        Write-Step $lineLine.Trim()
        exit 1
    }
    Write-Ok "line coverage = $pct% (>= $Target%)"
    if ($lineLine -match "缺口\s*([0-9]+)\s*文件" -and [int]$Matches[1] -gt 0) {
        Write-Warn "line-coverage gap files present: $($Matches[1])"
    }
    Write-Host "RESULT: PASS - line coverage verified" -ForegroundColor Green
    exit 0
}

Write-Bad "unable to parse line-coverage percentage from: $($lineLine.Trim())"
exit 1