param(
    [string]$ArtifactDir = "",
    [int]$Limit = 20,
    [string]$OutputPath = ""
)

Set-StrictMode -Version Latest
$ErrorActionPreference = "Stop"

$repoRoot = (Resolve-Path (Join-Path $PSScriptRoot "..\..")).ProviderPath
if ($ArtifactDir.Trim() -eq "") {
    $ArtifactDir = Join-Path $repoRoot "artifacts\fabric-loadtest"
}
if ($OutputPath.Trim() -eq "") {
    $OutputPath = Join-Path $ArtifactDir ("fabric-acceptance-summary-" + (Get-Date -Format "yyyyMMdd-HHmmss") + ".json")
}

function Get-PropertyValue {
    param([object]$Item, [string]$Name, $Default = $null)
    if ($null -eq $Item -or -not ($Item.PSObject.Properties.Name -contains $Name)) {
        return $Default
    }
    return $Item.$Name
}

function Convert-RouteModes {
    param([object]$TargetStats)
    $modes = [ordered]@{}
    if ($null -eq $TargetStats) {
        return $modes
    }
    foreach ($targetName in $TargetStats.PSObject.Properties.Name) {
        $stats = $TargetStats.$targetName
        $routeModes = Get-PropertyValue -Item $stats -Name "route_modes"
        if ($null -eq $routeModes) {
            continue
        }
        foreach ($mode in $routeModes.PSObject.Properties.Name) {
            if (-not $modes.Contains($mode)) {
                $modes[$mode] = 0
            }
            $modes[$mode] += [int]$routeModes.$mode
        }
    }
    return $modes
}

function Convert-TargetDistribution {
    param([object]$TargetStreams)
    $out = [ordered]@{}
    if ($null -eq $TargetStreams) {
        return $out
    }
    foreach ($name in $TargetStreams.PSObject.Properties.Name) {
        $out[$name] = [int]$TargetStreams.$name
    }
    return $out
}

$files = @(Get-ChildItem -LiteralPath $ArtifactDir -Filter "*-summary.json" -File | Sort-Object LastWriteTime -Descending | Select-Object -First $Limit)
$runs = @()
foreach ($file in $files) {
    try {
        $summary = Get-Content -LiteralPath $file.FullName -Raw | ConvertFrom-Json
    }
    catch {
        continue
    }
    $runs += [pscustomobject]@{
        run_id = Get-PropertyValue -Item $summary -Name "run_id" -Default $file.BaseName
        verdict = Get-PropertyValue -Item $summary -Name "verdict"
        verdict_reasons = Get-PropertyValue -Item $summary -Name "verdict_reasons"
        docker_context = Get-PropertyValue -Item $summary -Name "docker_context"
        topology_profile = Get-PropertyValue -Item $summary -Name "topology_profile"
        soak = [bool](Get-PropertyValue -Item $summary -Name "soak" -Default $false)
        total_streams = [int64](Get-PropertyValue -Item $summary -Name "total_streams" -Default 0)
        successful_streams = [int64](Get-PropertyValue -Item $summary -Name "successful_streams" -Default 0)
        failed_streams = [int64](Get-PropertyValue -Item $summary -Name "failed_streams" -Default 0)
        failover_events = [int64](Get-PropertyValue -Item $summary -Name "failover_events" -Default 0)
        migration_events = [int64](Get-PropertyValue -Item $summary -Name "migration_events" -Default 0)
        channel_opens = [int64](Get-PropertyValue -Item $summary -Name "channel_opens" -Default 0)
        channel_closes = [int64](Get-PropertyValue -Item $summary -Name "channel_closes" -Default 0)
        channel_leaks = [int64](Get-PropertyValue -Item $summary -Name "channel_leaks" -Default 0)
        throughput_bps = [int64](Get-PropertyValue -Item $summary -Name "throughput_bps" -Default 0)
        channel_churn_per_sec = [int64](Get-PropertyValue -Item $summary -Name "channel_churn_per_sec" -Default 0)
        ack_p95_ms = [int64](Get-PropertyValue -Item $summary -Name "ack_p95_ms" -Default 0)
        ack_p99_ms = [int64](Get-PropertyValue -Item $summary -Name "ack_p99_ms" -Default 0)
        setup_latency_p95_ms = [int64](Get-PropertyValue -Item $summary -Name "setup_latency_p95_ms" -Default 0)
        reroute_latency_p95_ms = [int64](Get-PropertyValue -Item $summary -Name "reroute_latency_p95_ms" -Default 0)
        route_modes = Convert-RouteModes -TargetStats (Get-PropertyValue -Item $summary -Name "target_stats")
        target_streams = Convert-TargetDistribution -TargetStreams (Get-PropertyValue -Item $summary -Name "target_streams")
        container_stats_samples_count = [int](Get-PropertyValue -Item $summary -Name "container_stats_samples_count" -Default 0)
        summary_path = $file.FullName
    }
}

$failed = @($runs | Where-Object { $_.verdict -ne "pass" })
$report = [pscustomobject]@{
    schema_version = "rap.fabric_acceptance_summary.v1"
    generated_at = (Get-Date).ToUniversalTime().ToString("o")
    artifact_dir = (Resolve-Path $ArtifactDir).ProviderPath
    runs_considered = $runs.Count
    pass_count = @($runs | Where-Object { $_.verdict -eq "pass" }).Count
    fail_count = $failed.Count
    all_considered_runs_passed = ($failed.Count -eq 0 -and $runs.Count -gt 0)
    runs = $runs
}

New-Item -ItemType Directory -Force -Path (Split-Path -Parent $OutputPath) | Out-Null
$json = $report | ConvertTo-Json -Depth 30
Set-Content -LiteralPath $OutputPath -Value $json -Encoding UTF8
$json