program MyApp;

{$mode objfpc}{$H+}{$J-}

uses
  DotEnv;

var
  Env: TDotEnv;
begin
  // Create and load .env file
  Env := TDotEnv.Create;
  Env.Load;  // Loads .env from current directory
  
  // Read values with type safety
  WriteLn('Database: ', Env.Get('DATABASE_URL'));
  WriteLn('Port: ', Env.GetInt('PORT', 3000));
  WriteLn('Debug mode: ', Env.GetBool('DEBUG', False));
  WriteLn('Pool size: ', Env.GetInt('DB_POOL_SIZE', 5));
  
  // No need to free - advanced records clean up automatically!
end.

var
  Env: TDotEnv;
  Options: TDotEnvOptions;
begin
  // 🟢 Simple usage
  Env := TDotEnv.Create;
  Env.Load;                    // Load .env
  Env.Load('.env.local');      // Load specific file
  
  // 🟡 With options
  Options := TDotEnvOptions.Default;
  Options.Override := True;    // Override existing env vars
  Options.Verbose := True;     // Print debug info  
  Options.Prefix := 'APP_';    // Prefix all keys with APP_
  
  Env := TDotEnv.CreateWithOptions(Options);
  Env.Load;
  
  // 🔵 Load multiple files (later files override earlier ones)
  Env.LoadMultiple(['.env', '.env.local', '.env.development']);

  // 🟣 Load from string (great for testing!)
  Env.LoadFromString('KEY=value' + LineEnding + 'OTHER=test');

  // 🌍 NEW in v1.1.0: Environment-aware loading
  Env.LoadForEnvironment('production');   // Loads .env + .env.production
  Env.LoadForEnvironment();               // Auto-detects from APP_ENV or NODE_ENV
end;

// 📝 Strings
Env.Get('KEY');                    // Returns '' if missing
Env.Get('KEY', 'default');         // Returns 'default' if missing
Env.GetRequired('KEY');            // Raises exception if missing

// 🔢 Integers  
Env.GetInt('PORT');                // Returns 0 if missing/invalid
Env.GetInt('PORT', 3000);          // Returns 3000 if missing/invalid
Env.GetIntRequired('PORT');        // Raises exception if missing/invalid

// ✅ Booleans (recognizes: true/false, yes/no, 1/0, on/off)
Env.GetBool('DEBUG');              // Returns False if missing
Env.GetBool('DEBUG', True);        // Returns True if missing
Env.GetBoolRequired('DEBUG');      // Raises exception if missing

// 🔬 Floats
Env.GetFloat('RATE');              // Returns 0.0 if missing/invalid
Env.GetFloat('RATE', 0.5);         // Returns 0.5 if missing/invalid
Env.GetFloatRequired('RATE');      // Raises exception if missing/invalid

// 📋 Arrays (splits comma-separated values)
Hosts := Env.GetArray('ALLOWED_HOSTS');        // Split by comma
Tags := Env.GetArray('TAGS', ';');             // Split by semicolon

// 💬 NEW in v1.1.0: Interactive prompts (for setup scripts)
DbUrl := Env.GetOrPrompt('DATABASE_URL',
                        'Enter database URL',
                        'postgres://localhost/mydb');
// Prompts user if DATABASE_URL is missing, uses existing value if present

var
  Missing: TStringDynArray;
  I: Integer;
begin
  // ✅ Check if all required keys exist
  if Env.Validate(['DATABASE_URL', 'SECRET_KEY', 'PORT']) then
    WriteLn('All required configuration present!')
  else
  begin
    // 📋 Get list of missing keys
    Missing := Env.GetMissing(['DATABASE_URL', 'SECRET_KEY', 'PORT']);
    WriteLn('Missing configuration:');
    for I := 0 to High(Missing) do
      WriteLn('  - ', Missing[I]);
    Halt(1);
  end;
end;

// 🔍 Check if key exists
if Env.Has('OPTIONAL_FEATURE') then
  EnableFeature;

// 📋 Get all keys and values
Keys := Env.Keys;           // TStringDynArray of all key names
Values := Env.Values;       // TStringDynArray of all values  
Pairs := Env.AsArray;       // TDotEnvPairArray with Key/Value records

// 🔢 Count loaded variables
WriteLn('Loaded ', Env.Count, ' environment variables');

// 🐛 Debug output (shows all loaded key=value pairs)
WriteLn(Env.ToString);

// 📁 See which files were loaded
for I := 0 to High(Env.LoadedFiles) do
  WriteLn('Loaded: ', Env.LoadedFiles[I]);

// 💾 Save environment variables to a file
Env := TDotEnv.Create;
Env.SetToEnv('DATABASE_URL', 'postgres://localhost/mydb');
Env.SetToEnv('PORT', '3000');
Env.SetToEnv('DEBUG', 'true');
Env.Save('.env');  // Writes to .env file

// 📋 Generate .env.example for version control
Env.Load('.env');
Env.GenerateExample('.env', '.env.example');
// Creates .env.example with keys but empty values

// 🌍 Environment-aware loading pattern
Env := TDotEnv.Create;
Env.LoadForEnvironment('development');   // Loads .env + .env.development
Env.LoadForEnvironment('production');    // Loads .env + .env.production
Env.LoadForEnvironment();                // Auto-detects from APP_ENV/NODE_ENV

// 💬 Interactive setup script example
Env := TDotEnv.Create;
Env.Load('.env');  // Try to load existing config
DbUrl := Env.GetOrPrompt('DATABASE_URL',
                        'Enter database URL',
                        'postgres://localhost/mydb');
Port := Env.GetOrPrompt('PORT', 'Enter port', '3000');
Env.Save('.env');  // Save the configuration
WriteLn('Configuration saved!');

uses DotEnv;

begin
  DotEnvLoad;                              // Load .env
  DotEnvLoad('.env.local');                // Load specific file
  
  WriteLn(DotEnvGet('DATABASE_URL'));      // Get value
  WriteLn(DotEnvGet('PORT', '3000'));      // Get with default
  
  DotEnvSet('RUNTIME_VAR', 'value');       // Set at runtime
end.

var
  Options: TDotEnvOptions;
begin
  Options := TDotEnvOptions.Default;  // Start with defaults
  Options.Override := True;
  Options.Prefix := 'MYAPP_';
  
  Env := TDotEnv.CreateWithOptions(Options);
  Env.Load;
  
  // KEY=value in .env becomes accessible as MYAPP_KEY
  WriteLn(Env.Get('MYAPP_KEY'));
end;

uses DotEnv;

var
  Env: TDotEnv;
begin
  Env := TDotEnv.Create;
  Env.Load;
  
  // 🔴 Handle missing required keys
  try
    Env.GetRequired('MISSING_KEY');
  except
    on E: EDotEnvMissingKey do
      WriteLn('Configuration error: ', E.Message);
  end;
  
  // 🔴 Handle invalid type conversions
  try
    Env.GetIntRequired('NOT_A_NUMBER');
  except
    on E: EDotEnvParseError do
      WriteLn('Parse error: ', E.Message);
  end;
end.