package xugu

import (
	"database/sql/driver"
	"encoding/base64"
	"encoding/binary"
	"errors"
	"fmt"
	"unsafe"
)

type xuguStmt struct {

	// 上下文连接句柄指针
	stmt_conn *xuguConn

	// 布尔值，用于标识执行的 SQL 语句是否已准备好
	prepared bool

	// 接受准备好的 SQL 语句的代码
	prename []byte

	// 布尔值，用于标识游标是否启用
	curopend bool

	// 游标名称
	curname []byte

	// 执行的 SQL 语句中的参数数量
	param_count int
	mysql       string

	// 上下文结果集句柄指针
	result unsafe.Pointer
}

/* Collect error information from the database server */
func (self *xuguStmt) get_error() error {
	// message := cgo_c_calloc(ERROR_BUFF_SIZE)
	// defer func() {
	// 	cgo_c_free(unsafe.Pointer(message))
	// }()

	// var length C.int
	// cgo_xgc_error(&self.stmt_conn, message, &length)
	// return errors.New(C.GoString(message))
	return errors.New("xuguStmt error")
}

/* {{ */
func (stmt *xuguStmt) Close() error {
	fmt.Println("\n>>>>>> (stmt *xuguStmt) Close method called")
	return nil
}

func (stmt *xuguStmt) NumInput() int {
	fmt.Println("\n>>>>>NumInput method called")

	parser := &xuguParse{
		bind_type:   0,
		param_count: 0,
		position:    0,
	}

	fmt.Println("stmt.mysql: ", stmt.mysql)
	return parser.assertParamCount(stmt.mysql)
	//return 0
}

func (stmt *xuguStmt) Exec(args []driver.Value) (driver.Result, error) {
	fmt.Println(">>>>>>>Exec method called")
	result := &xuguResult{
		affectedRows: 0,
		insertId:     0,
	}
	//最终发送消息给服务器
	XGC_Execute(stmt.stmt_conn, stmt.mysql)
	//处理服务器返回
	stmt.stmt_conn.conn.Read(stmt.stmt_conn.readBuff.buf)
	readBuf := stmt.stmt_conn.readBuff
	//fmt.Println("Message from server:", (buffer[:n]))
	fmt.Println("Message from server:", string(stmt.stmt_conn.readBuff.buf))
	//读取一字节
	char := readBuf.peekChar()
	switch char {
	case '$':
		fmt.Println("消息类型为$")
	case 'I':
		readBuf.idx++
		fmt.Println("消息类型为I")
		//Rowid_Len
		Rowid_Len := binary.BigEndian.Uint32(readBuf.readNext(4))
		fmt.Println("Rowid_Len", Rowid_Len)
		//Rowid_Data	// Base64 解码
		Rowid_Data, err := base64.StdEncoding.DecodeString(string(readBuf.readNext(int(Rowid_Len))))
		if err != nil {
			fmt.Println("Error decoding:", err)

		}
		fmt.Println("Rowid_Data: ", string(Rowid_Data))

	case 'U':
		fmt.Println("消息类型为U")
	case 'D':
		fmt.Println("消息类型为D")
	case 'E':
		fmt.Println("消息类型为E")
	case 'W':
		fmt.Println("消息类型为W")
	case 'M':
		fmt.Println("消息类型为M")
	}

	//return nil, errors.New("Exec not implemented")
	return result, nil
}

func (stmt *xuguStmt) Query(args []driver.Value) (driver.Rows, error) {
	fmt.Println("\n>>>>>>Query method called")
	fmt.Println("stmt.mysql: ", stmt.mysql)
	if switchSQLType(stmt.mysql) != SQL_SELECT {
		return nil, errors.New("The executed SQL statement is not a SELECT")
	}
	if !stmt.prepared {
		return nil, errors.New("SQL statement is not Prepared")
	}

	parser := &xuguParse{
		bind_type:   0,
		param_count: 0,
		position:    0,
	}

	if len(args) != 0 {
		for pos, param := range args {
			err := parser.assertParamType(param, pos)
			if err != nil {
				return nil, err
			}
		}

	}
	// if len(parser.Val) != parser.assertParamCount(stmt.mysql) {
	// 	return nil, errors.New("The number of parameters does not match")
	// }

	//最终发送消息给服务器
	XGC_Execute(stmt.stmt_conn, stmt.mysql)

	//----------------处理服务器查询返回

	stmt.stmt_conn.conn.Read(stmt.stmt_conn.readBuff.buf)

	//fmt.Println("Message from server:", (buffer[:n]))
	fmt.Println("Message from server:", string(stmt.stmt_conn.readBuff.buf))
	//fmt.Println("\nMessage from server2:", (stmt.stmt_conn.readBuff.buf))
	results, err := parseSelectResult(stmt.stmt_conn.readBuff)
	if err != nil {
		fmt.Println("parseSelectResult parseSelectResult err", err.Error())
		return nil, err
	}

	fmt.Println("results:", results)

	a := &xuguRows{
		results:   results,
		prepared:  stmt.prepared,
		rows_conn: stmt.stmt_conn,
	}
	fmt.Println("\n>>>>>>stmt Query  end==============================================================")
	return a, nil
}