;============================================================
;   iron_grpc.hsp — 簡易 gRPC クライアント (.NET版)
;
;   HttpClient を使用した gRPC-JSON 形式の呼び出し。
;   application/grpc+json コンテントタイプで HTTP/2 POST。
;   Protobuf は使わず JSON ベースの簡易版。hsp3net 専用。
;
;   API:
;     grpc_set_endpoint "http://localhost:50051"  サーバー設定
;     grpc_call "pkg.Service/Method", "json_body", response
;       Unary 呼び出し → stat (0=成功)
;
;   例:
;     #include "iron_grpc.hsp"
;     grpc_set_endpoint "http://localhost:50051"
;     grpc_call "greet.Greeter/SayHello", "{\"name\":\"HSP\"}", resp
;     if stat == 0 : mes resp
;
;   注意:
;     - 本モジュールは gRPC-JSON (非公式) を使用した簡易版
;     - 本格的な Protobuf シリアライズには別途 DLL が必要
;     - サーバー側が gRPC-JSON をサポートしている必要あり
;     - gRPC-Web や Envoy プロキシ経由での利用を想定
;============================================================

#ifndef __iron_grpc_hsp__
#define __iron_grpc_hsp__

#module iron_grpc

dim _grpc_cs_loaded, 1
sdim _grpc_endpoint, 256

#deffunc _grpc_load_cs
	if _grpc_cs_loaded : return
	sdim cs, 8192
	cs  = "using System;using System.Net;using System.Net.Http;"
	cs += "using System.Text;using System.IO;"
	cs += "public class HspGrpc {"
	cs += "  static string _endpoint=\"\";"
	cs += "  public static string SetEndpoint(string ep) { _endpoint=ep; return \"0|\"; }"
	; gRPC-Web compatible call using HttpWebRequest
	; (HttpClient with HTTP/2 requires .NET Core, so we use gRPC-Web format)
	cs += "  public static string Call(string method, string jsonBody) {"
	cs += "    try { if(_endpoint==\"\") return \"-1|endpoint not set\";"
	cs += "    string url=_endpoint+\"/\"+method;"
	cs += "    var req=(HttpWebRequest)WebRequest.Create(url);"
	cs += "    req.Method=\"POST\";"
	cs += "    req.ContentType=\"application/grpc-web-text\";"
	cs += "    req.Headers.Add(\"x-grpc-web\",\"1\");"
	cs += "    req.Accept=\"application/grpc-web-text\";"
	; gRPC-Web format: 1 byte flag + 4 byte length + body
	cs += "    var bodyBytes=Encoding.UTF8.GetBytes(jsonBody);"
	cs += "    var frame=new byte[5+bodyBytes.Length];"
	cs += "    frame[0]=0;"  ; no compression
	cs += "    frame[1]=(byte)((bodyBytes.Length>>24)&0xFF);"
	cs += "    frame[2]=(byte)((bodyBytes.Length>>16)&0xFF);"
	cs += "    frame[3]=(byte)((bodyBytes.Length>>8)&0xFF);"
	cs += "    frame[4]=(byte)(bodyBytes.Length&0xFF);"
	cs += "    Array.Copy(bodyBytes,0,frame,5,bodyBytes.Length);"
	cs += "    var b64=Convert.ToBase64String(frame);"
	cs += "    var sendBytes=Encoding.UTF8.GetBytes(b64);"
	cs += "    req.ContentLength=sendBytes.Length;"
	cs += "    using(var s=req.GetRequestStream()) s.Write(sendBytes,0,sendBytes.Length);"
	cs += "    using(var resp=(HttpWebResponse)req.GetResponse())"
	cs += "    using(var sr=new StreamReader(resp.GetResponseStream())) {"
	cs += "    string raw=sr.ReadToEnd();"
	; Decode gRPC-Web response (base64 -> skip 5 byte header -> UTF-8)
	cs += "    try { var decoded=Convert.FromBase64String(raw);"
	cs += "    if(decoded.Length>5) { string result=Encoding.UTF8.GetString(decoded,5,decoded.Length-5);"
	cs += "    return \"0|\"+result; }"
	cs += "    return \"0|\"+raw; }"
	cs += "    catch { return \"0|\"+raw; } } }"
	cs += "    catch(WebException we) {"
	cs += "    if(we.Response!=null) {"
	cs += "      using(var sr=new StreamReader(we.Response.GetResponseStream()))"
	cs += "      return \"-1|\"+sr.ReadToEnd(); }"
	cs += "    return \"-1|\"+we.Message; }"
	cs += "    catch(Exception e) { return \"-1|\"+e.Message; } }"
	cs += "}"
	loadnet cs, 3
	_grpc_cs_loaded = 1
	return

;------------------------------------------------------------
; grpc_set_endpoint "http://localhost:50051"
;   gRPC サーバーのエンドポイントを設定。
;------------------------------------------------------------
#deffunc grpc_set_endpoint str endpoint, \
	local pHelper, local pResult
	_grpc_load_cs
	_grpc_endpoint = endpoint
	newnet pHelper, "", "HspGrpc", 1
	netres pResult
	mcall pHelper, "SetEndpoint", endpoint
	return 0

;------------------------------------------------------------
; grpc_call "package.Service/Method", "json_body", var_response
;   Unary gRPC 呼び出し。stat=0 で成功。
;------------------------------------------------------------
#deffunc grpc_call str method, str json_body, var out_response, \
	local pHelper, local pResult, local s, local p
	_grpc_load_cs
	sdim out_response, 65536
	newnet pHelper, "", "HspGrpc", 1
	netres pResult
	mcall pHelper, "Call", method, json_body
	s = nettoval(pResult, 2)
	p = instr(s, 0, "|")
	if p < 0 : return -1
	rc = int(strmid(s, 0, p))
	out_response = strmid(s, p + 1, strlen(s) - p - 1)
	return rc

#global

#endif