# Importa configurazione e assembly necessari
Add-Type -AssemblyName System.Web
. "$PSScriptRoot\conf.ps1"

$scriptName = $MyInvocation.MyCommand.Name
$logFile = Join-Path $env:logDir "${scriptName}.log"
"start" | Out-File -FilePath $logFile

# Imposta il percorso di output nella cartella sql
$OutputPath = Join-Path $env:workdir "transito\tabelle"

# Verifica che la directory di output esista, altrimenti la crea
if (-not (Test-Path -Path $OutputPath)) {
    New-Item -ItemType Directory -Path $OutputPath | Out-Null
}

try {
    # Carica l'assembly System.Data
    Add-Type -AssemblyName System.Data

    # Query per estrarre la definizione delle tabelle
    $query = @"
    WITH TableColumns AS (
        SELECT DISTINCT
            t.object_id,
            (
                SELECT STUFF((
                    SELECT ',' + CHAR(13) + CHAR(10) +
                        CHAR(9) + '[' + c2.name + '] ' +
                        CASE 
                            WHEN t2.name IN ('char', 'varchar', 'nchar', 'nvarchar') 
                                THEN t2.name + '(' + 
                                    CASE 
                                        WHEN c2.max_length = -1 THEN 'MAX'
                                        WHEN t2.name LIKE 'n%' THEN CAST(c2.max_length/2 AS VARCHAR)
                                        ELSE CAST(c2.max_length AS VARCHAR)
                                    END + ')'
                            WHEN t2.name IN ('decimal', 'numeric') 
                                THEN t2.name + '(' + CAST(c2.[precision] AS VARCHAR) + ',' + CAST(c2.[scale] AS VARCHAR) + ')'
                            ELSE t2.name
                        END +
                        CASE WHEN c2.is_nullable = 0 THEN ' NOT NULL' ELSE ' NULL' END +
                        CASE WHEN ic.is_identity = 1 THEN ' IDENTITY(' + CAST(IDENT_SEED(OBJECT_SCHEMA_NAME(t.object_id) + '.' + OBJECT_NAME(t.object_id)) AS VARCHAR) + ',' + CAST(IDENT_INCR(OBJECT_SCHEMA_NAME(t.object_id) + '.' + OBJECT_NAME(t.object_id)) AS VARCHAR) + ')' ELSE '' END +
                        CASE WHEN dc.definition IS NOT NULL THEN ' DEFAULT ' + dc.definition ELSE '' END
                    FROM sys.columns c2
                    INNER JOIN sys.types t2 ON c2.user_type_id = t2.user_type_id
                    LEFT JOIN sys.identity_columns ic ON ic.object_id = c2.object_id AND ic.column_id = c2.column_id
                    LEFT JOIN sys.default_constraints dc ON dc.parent_object_id = c2.object_id AND dc.parent_column_id = c2.column_id
                    WHERE c2.object_id = t.object_id
                    ORDER BY c2.column_id
                    FOR XML PATH('')
                ), 1, 2, '')
            ) as ColumnDefinitions
        FROM sys.tables t
    ),
    TablePrimaryKeys AS (
        SELECT DISTINCT
            i.object_id,
            (
                SELECT CHAR(13) + CHAR(10) + 'ALTER TABLE [' + OBJECT_SCHEMA_NAME(i.object_id) + '].[' + OBJECT_NAME(i.object_id) + '] ADD CONSTRAINT [' + i.name + '] PRIMARY KEY ' +
                CASE WHEN i.type = 1 THEN 'CLUSTERED' ELSE 'NONCLUSTERED' END +
                ' (' + STUFF((
                    SELECT ',' + QUOTENAME(c2.name)
                    FROM sys.index_columns ic2
                    INNER JOIN sys.columns c2 ON c2.object_id = ic2.object_id AND c2.column_id = ic2.column_id
                    WHERE ic2.object_id = i.object_id AND ic2.index_id = i.index_id
                    ORDER BY ic2.key_ordinal
                    FOR XML PATH('')
                ), 1, 1, '') + ')'
            ) as PkDefinition
        FROM sys.indexes i
        WHERE i.is_primary_key = 1
    )
    SELECT 
        s.name as SchemaName,
        t.name as TableName,
        CONCAT(
            'CREATE TABLE [', s.name, '].[', t.name, '] (', CHAR(13), CHAR(10),
            tc.ColumnDefinitions,
            CHAR(13), CHAR(10), ')',
            ISNULL(pk.PkDefinition, '')
        ) as TableDefinition
    FROM sys.tables t
    INNER JOIN sys.schemas s ON t.schema_id = s.schema_id
    INNER JOIN TableColumns tc ON tc.object_id = t.object_id
    LEFT JOIN TablePrimaryKeys pk ON pk.object_id = t.object_id
    WHERE t.is_ms_shipped = 0

"@

    # Esegui la query
    Write-Host "Eseguo query su $env:dbHostInput..."
    "Eseguo query su $env:dbHostInput..." | Out-File -FilePath $logFile -Append

    try {
        # Crea la connessione e esegui la query
        $connectionString = "Server=$($env:dbHostInput);Database=$($env:dbNameInput);User Id=$($env:dbUserInput);Password=$($env:dbPasswordInput);TrustServerCertificate=True;Connection Timeout=30"
        Write-Host "Tentativo di connessione a $($env:dbHostInput)..."
        
        $connection = New-Object System.Data.SqlClient.SqlConnection($connectionString)
        $command = New-Object System.Data.SqlClient.SqlCommand($query, $connection)
        $adapter = New-Object System.Data.SqlClient.SqlDataAdapter($command)
        $dataset = New-Object System.Data.DataSet
        $adapter.Fill($dataset) | Out-Null
        $tables = $dataset.Tables[0]
    }
    catch {
        Write-Error "Errore di connessione al database: $($_.Exception.Message)"
        Write-Host "Dettagli connessione:"
        Write-Host "Server: $($env:dbHostInput)"
        Write-Host "Database: $($env:dbNameInput)"
        Write-Host "Utente: $($env:dbUserInput)"
        throw
    }
    
    Write-Host "Trovate $($tables.Count) tabelle"
    "Trovate $($tables.Count) tabelle" | Out-File -FilePath $logFile -Append

    # Funzione per formattare il nome del file
    function Format-FileName {
        param([string]$name)
        # Sostituisce caratteri non validi con underscore
        $invalidChars = [IO.Path]::GetInvalidFileNameChars()
        $invalidChars += '[', ']', ' ', '(', ')', '{', '}', '´', '`', '''', '"'
        $result = $name
        foreach ($char in $invalidChars) {
            $result = $result.Replace($char, '_')
        }
        return $result
    }

    # Per ogni tabella trovata
    Write-Host "Inizio elaborazione tabelle..."
    "Inizio elaborazione tabelle..." | Out-File -FilePath $logFile -Append

    foreach ($table in $tables) {
        $schemaName = Format-FileName $table.SchemaName
        $tableName = Format-FileName $table.TableName
        $definition = $table.TableDefinition

        # Crea il nome del file
        $fileName = Join-Path $OutputPath "${schemaName}_${tableName}.sql"
        
        Write-Host "Elaboro ${schemaName}.${tableName}..."
        "Elaboro ${schemaName}.${tableName}..." | Out-File -FilePath $logFile -Append

        # Pulisci e formatta il contenuto
        $content = $definition.Trim()
        # Rimuovi caratteri speciali e di escape HTML
        $content = $content -replace '
|#x0D;|\r|\n', "`r`n"
        $content = [System.Web.HttpUtility]::HtmlDecode($content)
        $content += "`r`nGO"

        # Rimuovi righe vuote multiple e normalizza i line endings
        $lines = $content -split "\r?\n" | Where-Object { -not [string]::IsNullOrWhiteSpace($_) }
        $content = $lines -join "`r`n"

        try {
            # Scrivi il contenuto nel file con codifica UTF8 con BOM
            [System.IO.File]::WriteAllText($fileName, $content, [System.Text.UTF8Encoding]::new($true))

            Write-Host "Creato file per tabella: ${schemaName}.${tableName}" -ForegroundColor Green
            "Creato file per tabella: ${schemaName}.${tableName}" | Out-File -FilePath $logFile -Append
        } catch {
            $errorMessage = "ERRORE durante la scrittura del file per ${schemaName}.${tableName}: $($_.Exception.Message)"
            Write-Host $errorMessage -ForegroundColor Red
            $errorMessage | Out-File -FilePath $logFile -Append
        }
    }

    Write-Host "`nEstrazione completata con successo!"
} catch {
    Write-Error "Errore durante l'estrazione delle tabelle: $_"
    exit 1
}