<#
.SYNOPSIS
    JingTian rclone Sync Script
    
.DESCRIPTION
    Syncs the local BenjaminTeam folder with the remote Ubuntu server.
    - Main folders: One-way sync (Windows -> Server)
    - _LLM_Sync folder: Bidirectional sync
    
.PARAMETER LocalPath
    Path to the local BenjaminTeam folder.
    
.PARAMETER RclonePath
    Path to rclone.exe. Default: auto-detect
    
.PARAMETER LogDir
    Directory for log files. Default: %LOCALAPPDATA%\JingTian\logs
    
.PARAMETER Verbose
    Show detailed output during sync.
#>

param(
    [string]$LocalPath = "",
    [string]$RclonePath = "",
    [string]$LogDir = "$env:LOCALAPPDATA\JingTian\logs",
    [switch]$VerboseOutput
)

# Configuration
$RemoteName = "jingtian-server"
$RemotePath = "/data/jingtian/BenjaminTeam"
$LLMSyncFolder = "_LLM_Sync"

# Find rclone if not specified
if (-not $RclonePath -or -not (Test-Path $RclonePath)) {
    $possiblePaths = @(
        "$env:LOCALAPPDATA\rclone\rclone.exe",
        "C:\rclone\rclone.exe",
        "rclone.exe"
    )
    foreach ($path in $possiblePaths) {
        if (Test-Path $path) {
            $RclonePath = $path
            break
        }
    }
}

if (-not (Test-Path $RclonePath)) {
    Write-Error "rclone not found. Please run setup.ps1 first."
    exit 1
}

# Find LocalPath if not specified (check common locations)
if (-not $LocalPath -or -not (Test-Path $LocalPath)) {
    $searchPaths = @(
        "$env:USERPROFILE\Documents\BenjaminTeam",
        "$env:USERPROFILE\Documents\Benjamin Team",
        "D:\BenjaminTeam",
        "C:\BenjaminTeam"
    )
    foreach ($path in $searchPaths) {
        if (Test-Path $path) {
            $LocalPath = $path
            break
        }
    }
}

if (-not (Test-Path $LocalPath)) {
    Write-Error "BenjaminTeam folder not found. Please specify -LocalPath"
    exit 1
}

# Setup logging
$timestamp = Get-Date -Format "yyyy-MM-dd_HH-mm-ss"
$logFile = Join-Path $LogDir "sync.log"
$detailLogFile = Join-Path $LogDir "sync_$timestamp.log"

if (-not (Test-Path $LogDir)) {
    New-Item -ItemType Directory -Path $LogDir -Force | Out-Null
}

function Write-Log {
    param([string]$Message, [string]$Level = "INFO")
    $ts = Get-Date -Format "yyyy-MM-dd HH:mm:ss"
    $logLine = "[$ts] [$Level] $Message"
    Add-Content -Path $logFile -Value $logLine
    
    if ($VerboseOutput) {
        switch ($Level) {
            "ERROR" { Write-Host $logLine -ForegroundColor Red }
            "WARN"  { Write-Host $logLine -ForegroundColor Yellow }
            "OK"    { Write-Host $logLine -ForegroundColor Green }
            default { Write-Host $logLine }
        }
    }
}

# ============================================================
# MAIN SYNC LOGIC
# ============================================================

Write-Log "========== Sync Started =========="
Write-Log "Local:  $LocalPath"
Write-Log "Remote: ${RemoteName}:${RemotePath}"

$syncErrors = @()
$startTime = Get-Date

# ------------------------------------------------------------
# Phase 1: One-way sync (Windows -> Server) for main folders
# Excludes _LLM_Sync which is handled separately
# ------------------------------------------------------------

Write-Log "Phase 1: Syncing main folders (Windows -> Server)..."

$rcloneArgs = @(
    "sync",
    $LocalPath,
    "${RemoteName}:${RemotePath}",
    "--exclude", "$LLMSyncFolder/**",
    "--transfers", "4",
    "--checkers", "8",
    "--contimeout", "60s",
    "--timeout", "300s",
    "--retries", "3",
    "--low-level-retries", "10",
    "--stats", "1m",
    "--stats-one-line",
    "--log-file", $detailLogFile,
    "--log-level", "INFO"
)

if ($VerboseOutput) {
    $rcloneArgs += "--progress"
}

try {
    $result = & $RclonePath @rcloneArgs 2>&1
    if ($LASTEXITCODE -eq 0) {
        Write-Log "Phase 1 complete: Main folders synced successfully" "OK"
    } else {
        Write-Log "Phase 1 warning: rclone exited with code $LASTEXITCODE" "WARN"
        $syncErrors += "Main folder sync had warnings (exit code: $LASTEXITCODE)"
    }
} catch {
    Write-Log "Phase 1 error: $_" "ERROR"
    $syncErrors += "Main folder sync failed: $_"
}

# ------------------------------------------------------------
# Phase 2: Bidirectional sync for _LLM_Sync folder
# Uses rclone bisync for true bidirectional sync
# ------------------------------------------------------------

Write-Log "Phase 2: Syncing _LLM_Sync folder (bidirectional)..."

$llmLocalPath = Join-Path $LocalPath $LLMSyncFolder
$llmRemotePath = "${RemoteName}:${RemotePath}/${LLMSyncFolder}"

# Ensure local _LLM_Sync exists
if (-not (Test-Path $llmLocalPath)) {
    New-Item -ItemType Directory -Path $llmLocalPath -Force | Out-Null
    Write-Log "Created local _LLM_Sync folder"
}

# Check if bisync has been initialized (look for .rclone-bisync directory)
$bisyncStateDir = "$env:USERPROFILE\.cache\rclone\bisync"
$bisyncStateFile = Join-Path $bisyncStateDir "*.lst"

# For first run, we need to use --resync to initialize
$needsResync = $false
if (-not (Test-Path $bisyncStateDir) -or -not (Get-ChildItem $bisyncStateFile -ErrorAction SilentlyContinue)) {
    Write-Log "First bisync run detected, will initialize with --resync"
    $needsResync = $true
}

$bisyncArgs = @(
    "bisync",
    $llmLocalPath,
    $llmRemotePath,
    "--transfers", "4",
    "--checkers", "8",
    "--contimeout", "60s",
    "--timeout", "300s",
    "--retries", "3",
    "--log-file", $detailLogFile,
    "--log-level", "INFO"
)

if ($needsResync) {
    $bisyncArgs += "--resync"
    $bisyncArgs += "--resync-mode", "newer"
}

if ($VerboseOutput) {
    $bisyncArgs += "--progress"
}

try {
    $result = & $RclonePath @bisyncArgs 2>&1
    if ($LASTEXITCODE -eq 0) {
        Write-Log "Phase 2 complete: _LLM_Sync folder synced successfully" "OK"
    } else {
        # bisync can return non-zero for various reasons, check output
        Write-Log "Phase 2 warning: bisync exited with code $LASTEXITCODE" "WARN"
        $syncErrors += "_LLM_Sync bisync had warnings (exit code: $LASTEXITCODE)"
    }
} catch {
    Write-Log "Phase 2 error: $_" "ERROR"
    $syncErrors += "_LLM_Sync sync failed: $_"
}

# ------------------------------------------------------------
# Summary
# ------------------------------------------------------------

$endTime = Get-Date
$duration = $endTime - $startTime

Write-Log "========== Sync Completed =========="
Write-Log "Duration: $($duration.TotalSeconds.ToString('F1')) seconds"

if ($syncErrors.Count -gt 0) {
    Write-Log "Completed with $($syncErrors.Count) warning(s):" "WARN"
    foreach ($err in $syncErrors) {
        Write-Log "  - $err" "WARN"
    }
    exit 1
} else {
    Write-Log "All syncs completed successfully" "OK"
    exit 0
}