unit PM.EmbeddedAssets;

(*
  Serves the password-manager HTML/JS/CSS from Win32 RCDATA resources
  embedded inside PMServer.exe by BuildAssets.ps1.

  Workflow:
    1. Edit ../../index.html, ../../js/*.js, ../../css/*.css
    2. Run delphi-backend/assets/BuildAssets.ps1
    3. Rebuild — exe ships self-contained
    4. Run — TryServe pulls bytes from HInstance resources

  No disk I/O at runtime. No external files needed beside PMServer.exe.

  The manifest (URL path -> resource name) is generated alongside the .res:
  delphi-backend/assets/assets.inc, included below via {$I}. If the file
  does not exist (BuildAssets.ps1 never ran), the compile-time fallback
  registers no assets and TryServe always returns False.
*)

interface

uses
  System.SysUtils, System.Classes,
  IdCustomHTTPServer;

type
  TEmbeddedAsset = record
    UrlPath: string;
    ResName: string;
  end;

function TryServeEmbedded(ARequest: TIdHTTPRequestInfo;
  AResponse: TIdHTTPResponseInfo): Boolean;

implementation

uses
  Winapi.Windows;

// The manifest is auto-generated. A stub is checked in so the project
// compiles before BuildAssets.ps1 ever runs; running the script overwrites
// it with the real list.
{$I ..\assets\assets.inc}

function MimeTypeFor(const AExt: string): string;
var
  E: string;
begin
  E := LowerCase(AExt);
  if (E = '.html') or (E = '.htm') then Exit('text/html; charset=utf-8');
  if E = '.js'   then Exit('application/javascript; charset=utf-8');
  if E = '.mjs'  then Exit('application/javascript; charset=utf-8');
  if E = '.css'  then Exit('text/css; charset=utf-8');
  if E = '.json' then Exit('application/json; charset=utf-8');
  if E = '.svg'  then Exit('image/svg+xml');
  if E = '.png'  then Exit('image/png');
  if E = '.jpg'  then Exit('image/jpeg');
  if E = '.jpeg' then Exit('image/jpeg');
  if E = '.gif'  then Exit('image/gif');
  if E = '.ico'  then Exit('image/x-icon');
  if E = '.woff' then Exit('font/woff');
  if E = '.woff2' then Exit('font/woff2');
  Result := 'application/octet-stream';
end;

function FindResourceFor(const AUrlPath: string; out AResName: string): Boolean;
var
  I: Integer;
  LPath: string;
begin
  LPath := AUrlPath;
  if (LPath = '') or (LPath = '/') then LPath := '/index.html';
  for I := 0 to EMBEDDED_ASSET_COUNT - 1 do
    if SameText(EMBEDDED_ASSETS[I].UrlPath, LPath) then
    begin
      AResName := EMBEDDED_ASSETS[I].ResName;
      Exit(True);
    end;
  Result := False;
end;

function TryServeEmbedded(ARequest: TIdHTTPRequestInfo;
  AResponse: TIdHTTPResponseInfo): Boolean;
var
  LResName, LExt: string;
  LStream: TResourceStream;
  LMS: TMemoryStream;
begin
  Result := False;
  if not SameText(ARequest.Command, 'GET') then Exit;
  if not FindResourceFor(ARequest.Document, LResName) then Exit;
  if FindResource(HInstance, PChar(LResName), RT_RCDATA) = 0 then Exit;

  LExt := ExtractFileExt(ARequest.Document);
  if (LExt = '') and ((ARequest.Document = '') or (ARequest.Document = '/')) then
    LExt := '.html';
  AResponse.ContentType := MimeTypeFor(LExt);

  LStream := TResourceStream.Create(HInstance, LResName, RT_RCDATA);
  try
    // Copy into a TMemoryStream so Indy can own and free it after the response.
    LMS := TMemoryStream.Create;
    LMS.CopyFrom(LStream, 0);
    LMS.Position := 0;
    AResponse.ContentStream   := LMS;
    AResponse.FreeContentStream := True;
  finally
    LStream.Free;
  end;
  AResponse.ResponseNo := 200;
  Result := True;
end;

end.