[CmdletBinding()]
param(
    [Parameter(Mandatory = $true)]
    [string]$PsqlPath,

    [Parameter(Mandatory = $true)]
    [string]$AdminUser,

    [Parameter(Mandatory = $true)]
    [string]$AdminPassword,

    [Parameter(Mandatory = $true)]
    [ValidateRange(1, 65535)]
    [int]$PostgreSqlPort,

    [Parameter(Mandatory = $true)]
    [string]$DatabaseName,

    [Parameter(Mandatory = $true)]
    [string]$DatabaseUser,

    [Parameter(Mandatory = $true)]
    [string]$DatabasePassword,

    [Parameter(Mandatory = $true)]
    [ValidateRange(1, 65535)]
    [int]$ApplicationPort,

    [Parameter(Mandatory = $false)]
    [ValidateSet('full', 'cartridge')]
    [string]$Edition = 'full',

    [Parameter(Mandatory = $true)]
    [string]$ConfigPath
)

$ErrorActionPreference = 'Stop'

trap {
    $logDirectory = Split-Path -Parent $ConfigPath
    New-Item -ItemType Directory -Path $logDirectory -Force -ErrorAction SilentlyContinue | Out-Null
    $_ | Out-String | Set-Content -LiteralPath (Join-Path $logDirectory 'install-error.log') -Encoding UTF8
    $env:PGPASSWORD = $null
    exit 1
}

function Assert-SafeIdentifier {
    param([string]$Value, [string]$Label)
    if ($Value -notmatch '^[A-Za-z_][A-Za-z0-9_]*$') {
        throw "$Label содержит недопустимые символы."
    }
}

function Quote-Identifier {
    param([string]$Value)
    return '"' + $Value.Replace('"', '""') + '"'
}

function Quote-Literal {
    param([string]$Value)
    return "'" + $Value.Replace("'", "''") + "'"
}

function Convert-PsqlOutput {
    param([string]$Text)

    if ([string]::IsNullOrEmpty($Text)) {
        return $Text
    }

    # Russian PostgreSQL messages can be emitted in the Windows ANSI code page
    # while Windows PowerShell 5.1 decodes them as the OEM code page.
    if ($Text -match '[\u2500-\u259F]') {
        try {
            $culture = [System.Globalization.CultureInfo]::CurrentCulture
            $oemEncoding = [System.Text.Encoding]::GetEncoding($culture.TextInfo.OEMCodePage)
            $ansiEncoding = [System.Text.Encoding]::GetEncoding($culture.TextInfo.ANSICodePage)
            return $ansiEncoding.GetString($oemEncoding.GetBytes($Text))
        }
        catch {
            return $Text
        }
    }

    return $Text
}

function Invoke-Psql {
    param(
        [string]$Database,
        [string]$Sql,
        [string]$Username = $AdminUser,
        [switch]$Capture
    )

    $sqlFilePath = Join-Path `
        ([System.IO.Path]::GetTempPath()) `
        ("inventera-{0}.sql" -f ([Guid]::NewGuid().ToString('N')))

    [System.IO.File]::WriteAllText(
        $sqlFilePath,
        $Sql + [Environment]::NewLine,
        [System.Text.UTF8Encoding]::new($false)
    )

    try {
        $arguments = @(
            '--host', '127.0.0.1',
            '--port', [string]$PostgreSqlPort,
            '--username', $Username,
            '--dbname', $Database,
            '--no-password',
            '--set', 'ON_ERROR_STOP=1',
            '--tuples-only',
            '--no-align',
            '--file', $sqlFilePath
        )

        $previousErrorActionPreference = $ErrorActionPreference
        try {
            $ErrorActionPreference = 'Continue'
            $output = & $PsqlPath @arguments 2>&1
            $exitCode = $LASTEXITCODE
        }
        finally {
            $ErrorActionPreference = $previousErrorActionPreference
        }

        $outputText = Convert-PsqlOutput -Text (
            ($output -join [Environment]::NewLine).Trim()
        )

        if ($exitCode -ne 0) {
            if ($outputText -eq '') {
                $outputText = "psql завершился с кодом $exitCode."
            }
            throw $outputText
        }

        if ($Capture) {
            return $outputText
        }

        if ($outputText -ne '') {
            Write-Host $outputText
        }
    }
    finally {
        Remove-Item -LiteralPath $sqlFilePath -Force -ErrorAction SilentlyContinue
    }
}

if (-not (Test-Path -LiteralPath $PsqlPath -PathType Leaf)) {
    throw "Не найден psql.exe: $PsqlPath"
}

Assert-SafeIdentifier -Value $AdminUser -Label 'Логин администратора PostgreSQL'
Assert-SafeIdentifier -Value $DatabaseName -Label 'Имя базы данных'
Assert-SafeIdentifier -Value $DatabaseUser -Label 'Логин пользователя базы данных'

$env:PGPASSWORD = $AdminPassword
$connected = $false
$lastConnectionError = $null

for ($attempt = 1; $attempt -le 45; $attempt++) {
    try {
        Invoke-Psql -Database 'postgres' -Sql 'SELECT 1;' | Out-Null
        $connected = $true
        break
    }
    catch {
        $lastConnectionError = $_
        Start-Sleep -Seconds 2
    }
}

if (-not $connected) {
    throw "Не удалось подключиться к PostgreSQL на порту $PostgreSqlPort. $lastConnectionError"
}

$databaseIdentifier = Quote-Identifier $DatabaseName
$databaseLiteral = Quote-Literal $DatabaseName
$userIdentifier = Quote-Identifier $DatabaseUser
$userLiteral = Quote-Literal $DatabaseUser
$passwordLiteral = Quote-Literal $DatabasePassword

$roleExists = Invoke-Psql -Database 'postgres' -Sql "SELECT 1 FROM pg_roles WHERE rolname = $userLiteral;" -Capture
if ($roleExists -eq '1') {
    Invoke-Psql -Database 'postgres' -Sql "ALTER ROLE $userIdentifier WITH LOGIN PASSWORD $passwordLiteral;"
}
else {
    Invoke-Psql -Database 'postgres' -Sql "CREATE ROLE $userIdentifier WITH LOGIN PASSWORD $passwordLiteral;"
}

$databaseExists = Invoke-Psql -Database 'postgres' -Sql "SELECT 1 FROM pg_database WHERE datname = $databaseLiteral;" -Capture
if ($databaseExists -ne '1') {
    Invoke-Psql -Database 'postgres' -Sql "CREATE DATABASE $databaseIdentifier OWNER $userIdentifier ENCODING 'UTF8';"
}
else {
    Invoke-Psql -Database 'postgres' -Sql "ALTER DATABASE $databaseIdentifier OWNER TO $userIdentifier;"
}

Invoke-Psql -Database 'postgres' -Sql "GRANT ALL PRIVILEGES ON DATABASE $databaseIdentifier TO $userIdentifier;"

$env:PGPASSWORD = $DatabasePassword
try {
    Invoke-Psql `
        -Database $DatabaseName `
        -Username $DatabaseUser `
        -Sql 'SELECT 1;' | Out-Null
}
catch {
    throw "Не удалось проверить подключение с учётными данными приложения. $_"
}

$configDirectory = Split-Path -Parent $ConfigPath
New-Item -ItemType Directory -Path $configDirectory -Force | Out-Null

$config = [ordered]@{
    edition = $Edition
    database = [ordered]@{
        host = '127.0.0.1'
        port = $PostgreSqlPort
        name = $DatabaseName
        user = $DatabaseUser
        password = $DatabasePassword
    }
    application = [ordered]@{
        host = '0.0.0.0'
        port = $ApplicationPort
    }
}

$config | ConvertTo-Json -Depth 4 | Set-Content -LiteralPath $ConfigPath -Encoding UTF8
$env:PGPASSWORD = $null
Write-Host "База данных $DatabaseName и конфигурация Inventera подготовлены."