unit datamodule;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, FileUtil, ExtCtrls, ZConnection, ZDataset, IdHTTP, MQTT,
  LR_Class, LR_Desgn, LR_DBSet, FPReportDesigner, fpreport, fpJson, intf,
  LMessages, LCLIntf, Forms;

type

  { TDM }

  TDM = class(TDataModule)
    conn: TZConnection;
    http: TIdHTTP;
    InnerQry: TZQuery;
    MqttAutoPing: TTimer;
    pubQry: TZQuery;
    procedure MqttAutoPingTimer(Sender: TObject);
  private

  public
    MQTTClient:TMQTTClient;

    WebServer:string;//服务器地址
    UName:string;//登录用户名
    UUID:string;//用户UUID
    USign:string;//用户签名图片地址
    UGonghao:string;//用户工号
    UOffice:string;//用户科室
    DB_Host:string;//数据库地址
    DB_Name:string;//数据库名称
    DB_Port:integer;//数据库端口
    DB_User:string;//数据库用户名
    DB_Pwd:string;//数据库密码
    Use_Local_goods:boolean;//是否使用本地商品库存
    Company:string;//公司名称
    Department:string;//部门名称
    DB_MsgHost:string;//消息服务器地址
    DB_MsgPort:integer;//消息服务器端口

    PrinterID:string;//打印机台编号
    PrinterName:string;//选中的打印机名称
    PrintTemplate:string;//打印模板文件

    procedure AddSysLog(AAction,ADetail:string);//记录系统日志
    procedure CreateMqttClient;//创建消息客户端对象
    function  ConectMqttServer:boolean;//连接到消息服务器并订阅主题
    function CreateSendMessageOfJson(ATopic, APayload:string;ACategory:string=''):string;//创建发送消息时的JSON字符串

    procedure OnMqttConnAck(Sender: TObject; ReturnCode: integer);
    procedure OnMqttPingResp(Sender: TObject);
    procedure OnMqttPublish(Sender: TObject; topic, payload: ansistring; retain: boolean);
    procedure OnMqttSubAck(Sender: TObject; MessageID: integer; GrantedQoS: integer);
    procedure OnMqttUnsubAck(Sender: TObject; MessageID: integer);

    function ExtractDanhaoFromJsonString(AString:string):string;//从JSON字符串中解析出处方单号
  end;

var
  DM: TDM;

implementation

{$R *.frm}

{ TDM }

procedure TDM.MqttAutoPingTimer(Sender: TObject);
begin
  if MqttClient<>nil then
  begin
    if MqttClient.isConnected then
    begin
      try
        MqttClient.PingReq;
      finally
      end;
    end;
  end;
end;

procedure TDM.AddSysLog(AAction, ADetail: string);
begin
  with InnerQry do
  begin
    Close;
    Sql.Clear;
    Sql.Add('insert into public.sys_logs (uuid, uname, ukind, action, detail) values (:uuid, :uname, :ukind, :action, :detail)');
    Params.ParamByName('uuid').AsString:=Self.UUID;
    Params.ParamByName('uname').AsString:=Self.UName;
    Params.ParamByName('ukind').AsString:='s';
    Params.ParamByName('action').AsString:=AAction;
    Params.ParamByName('detail').AsString:=ADetail;
    ExecSQL;
  end;
end;

procedure TDM.CreateMqttClient;
begin
  MQTTClient:=TMQTTClient.Create(Dm.DB_MsgHost,Dm.DB_MsgPort);
  MQTTClient.OnConnAck:=@OnMqttConnAck;
  MQTTClient.OnPingResp:=@OnMqttPingResp;
  MQTTClient.OnPublish:=@OnMqttPublish;
  MQTTClient.OnSubAck:=@OnMqttSubAck;
  MQTTClient.OnUnSubAck:=@OnMqttUnsubAck;
end;

function TDM.ConectMqttServer: boolean;
var
  mTimeout:Longword;
begin
  Result:=False;
  try
    MqttClient.Connect;
  except
    Result:=False;
    Exit;
  end;
  mTimeout:=GetTickCount64;
  while (GetTickCount64-mTimeout)<30000 do
  begin
    if MqttClient.isConnected then
    begin
      //订阅主题
      MqttClient.Subscribe('$queue/chufangprint/#');//处方打印
      Result:=True;
      Break;
    end;
  end;
end;

function TDM.CreateSendMessageOfJson(ATopic, APayload: string; ACategory: string
  ): string;
begin
  //生成发送消息的JSON字符串
  Result:='{"topic":"'+ATopic+'","payload":'+APayload+'}';
end;

procedure TDM.OnMqttConnAck(Sender: TObject; ReturnCode: integer);
begin

end;

procedure TDM.OnMqttPingResp(Sender: TObject);
begin

end;

procedure TDM.OnMqttPublish(Sender: TObject; topic, payload: ansistring;
  retain: boolean);
var
  m:string;
begin
  m:=Self.CreateSendMessageOfJson(topic,payload);
  SendMessage(Application.MainFormHandle,MSG_PUBLISH_MESSAGE,integer(@m),1);
end;

procedure TDM.OnMqttSubAck(Sender: TObject; MessageID: integer;
  GrantedQoS: integer);
begin

end;

procedure TDM.OnMqttUnsubAck(Sender: TObject; MessageID: integer);
begin

end;

function TDM.ExtractDanhaoFromJsonString(AString: string): string;
var
  mJson,mPayload:TJsonData;
  mTopic:string;
  mStream:TStringStream;
begin
  {Payload结构:
    {"sid":"101",
     "sname":"李时珍",
     "stime":"2021-06-01 22:18:48",
     "scat":"：",
     "smsg":"CFSD10100000054"}
  }
  Result:='';
  mStream:=TStringStream.Create(AString,TEncoding.UTF8);
  mStream.Seek(0,soBeginning);
  try
    mJson:=GetJson(mStream);
  except
    mStream.Free;
    Exit;
  end;
  mStream.Free;
  if mJson.FindPath('topic')<>nil then
  begin
    mTopic:=mJson.FindPath('topic').AsString;
    if Pos('chufangprint',mTopic)=1 then
    begin
      //只处理chufangprint频道消息
      mPayload:=mJson.FindPath('payload');
      if mPayload<>nil then
      begin
        if mPayload.FindPath('smsg')<>nil then
          Result:=mPayload.FindPath('smsg').AsString;
      end;
    end;
  end;
end;

end.