/// <summary>
/// - Processes a character event into an Action that occurs while in the DcsParam state.
/// Events in this state will:
/// 1. Ignore C0 control characters
/// 2. Ignore Delete characters
/// 3. Collect DCS parameter data
/// 4. Enter DcsIntermediate if we see an intermediate
/// 5. Begin to ignore all remaining parameters when an invalid character is detected (DcsIgnore)
/// 6. Dispatch the Final character in preparation for parsing the data string
/// </summary>
/// <param name="ch"></param>
private void EventDCSParam(byte ch)
{
if (ASCIIChars.IsC0Code(ch))
{
this.ActionIgnore(ch);
}
else if (ASCIIChars.IsDelete(ch))
{
this.ActionIgnore(ch);
}
else if (ASCIIChars.IsNumericParamValue(ch) || ASCIIChars.IsParameterDelimiter(ch))
{
this.ActionParam(ch);
}
else if (ASCIIChars.IsIntermediate(ch))
{
this.ActionCollect(ch);
this.EnterDCSIntermediate();
}
else if (ASCIIChars.IsParameterInvalid(ch))
{
this.EnterDCSIgnore();
}
else
{
this.ActionDCSDispatch(ch);
}
}
/// <summary>
/// 当状态改变为Ground的时候触发
/// </summary>
/// <param name="ch"></param>
private void EventGround(byte ch)
{
if (ASCIIChars.IsC0Code(ch) || ASCIIChars.IsDelete(ch))
{
// 如果是C0控制字符和Delete字符，说明要执行动作
this.ActionExecute(ch);
}
else if (ASCIIChars.IsPrintable(ch))
{
// 其他字符直接打印
this.ActionPrint(ch);
}
else
{
// 不是可见字符，当多字节字符处理，用UTF8编码
// UTF8参考：https://www.cnblogs.com/fnlingnzb-learner/p/6163205.html
if (this.unicodeText.Count == 0)
{
bool bit6 = BytesExtentions.GetBit(ch, 5);
this.unicodeText.Capacity = bit6 ? 3 : 2;
}
this.unicodeText.Add(ch);
if (this.unicodeText.Count == this.unicodeText.Capacity)
{
string text = Encoding.UTF8.GetString(this.unicodeText.ToArray());
this.ActionPrint(text);
this.unicodeText.Clear();
}
}
}
/// <summary>
/// - Processes a character event into an Action that occurs while in the CsiEntry state.
/// Events in this state will:
/// 1. Execute C0 control characters
/// 2. Ignore Delete characters
/// 3. Collect Intermediate characters
/// 4. Begin to ignore all remaining parameters when an invalid character is detected (CsiIgnore)
/// 5. Store parameter data
/// 6. Collect Control Sequence Private markers
/// 7. Dispatch a control sequence with parameters for action
/// </summary>
/// <param name="ch"></param>
private void EventCSIEntry(byte ch)
{
if (ASCIIChars.IsC0Code(ch))
{
this.ActionExecute(ch);
}
else if (ASCIIChars.IsDelete(ch))
{
this.ActionIgnore(ch);
}
else if (ASCIIChars.IsIntermediate(ch))
{
this.ActionCollect(ch);
this.EnterCSIIntermediate();
}
else if (ASCIIChars.IsCSIInvalid(ch))
{
this.EnterCSIIgnore();
}
else if (ASCIIChars.IsNumericParamValue(ch) || ASCIIChars.IsParameterDelimiter(ch))
{
this.ActionParam(ch);
this.EnterCSIParam();
}
else if (ASCIIChars.IsCSIPrivateMarker(ch))
{
this.ActionCollect(ch);
this.EnterCSIParam();
}
else
{
this.ActionCSIDispatch(ch);
this.EnterGround();
}
}
/// <summary>
/// - Processes a character event into a Action that occurs while in the OscParam state.
/// Events in this state will:
/// 1. Trigger the OSC action associated with the param on an OscTerminator
/// 2. If we see a ESC, enter the OscTermination state. We'll wait for one
/// more character before we dispatch the string.
/// 3. Ignore OscInvalid characters.
/// 4. Collect everything else into the OscString
/// </summary>
/// <param name="ch"></param>
private void EventOSCString(byte ch)
{
if (ASCIIChars.IsOSCTerminator(ch))
{
// 出现了OSC结束符，那么进入Ground状态
this.ActionOSCDispatch(ch);
this.EnterGround();
}
else if (ASCIIChars.IsEscape(ch))
{
// OSC状态下出现了ESC字符，那么有两种情况会出现：
// 1. ESC后面有ST字符，说明是OSC状态结束了
// 2. ESC后面没有ST字符，说明是ESC状态
// 所以这里定义一个OSCTermination状态来处理这两种状态
this.EnterOSCTermination();
}
else if (ASCIIChars.IsOSCIndicator(ch))
{
// OSC非法字符，忽略
this.ActionIgnore(ch);
}
else
{
// 剩下的就是OSC的有效字符，收集
this.oscString.Append((char)ch);
}
}
/// <summary>
/// - Processes a character event into an Action that occurs while in the EscapeIntermediate state.
/// Events in this state will:
/// 1. Execute C0 control characters
/// 2. Ignore Delete characters
/// 3. Collect Intermediate characters
/// 4. Dispatch an Escape action.
/// </summary>
/// <param name="ch"></param>
private void EventEscapeIntermediate(byte ch)
{
if (ASCIIChars.IsC0Code(ch))
{
this.ActionExecute(ch);
}
else if (ASCIIChars.IsIntermediate(ch))
{
this.ActionCollect(ch);
}
else if (ASCIIChars.IsDelete(ch))
{
this.ActionIgnore(ch);
}
else if (this.isAnsiMode)
{
this.ActionEscDispatch(ch);
this.EnterGround();
}
else if (ASCIIChars.IsVt52CursorAddress(ch))
{
this.EnterVt52Param();
}
else
{
this.ActionVt52EscDispatch(ch);
this.EnterGround();
}
}
/// <summary>
/// 当状态变成Escape的时候触发
/// </summary>
/// <param name="ch"></param>
private void EventEscape(byte ch)
{
if (ASCIIChars.IsC0Code(ch))
{
this.ActionExecute(ch);
}
else if (ASCIIChars.IsDelete(ch))
{
this.ActionIgnore(ch);
}
else if (ASCIIChars.IsIntermediate(ch))
{
this.ActionCollect(ch);
this.EnterEscapeIntermediate();
}
else if (this.isAnsiMode)
{
if (ASCIIChars.IsCSIIndicator(ch))
{
// 0x5B，进入到了csi entry状态
this.EnterCSIEntry();
}
else if (ASCIIChars.IsOSCIndicator(ch))
{
// 0x5D，进入到了osc状态
this.EnterOSCParam();
}
else if (ASCIIChars.IsDCSIndicator(ch))
{
// 0x50，进入到了dcs状态
this.EnterDCSEntry();
}
else
{
this.ActionEscDispatch(ch);
this.EnterGround();
}
}
else if (ASCIIChars.IsVt52CursorAddress(ch))
{
// 判断是否是VT52模式下的移动光标指令, 当进入了VT52模式下才会触发
// 在VT52模式下只有移动光标的指令有参数，所以这里把移动光标的指令单独做处理
this.EnterVt52Param();
}
else
{
// 这里是其他的不带参数的VT52控制字符
this.ActionVt52EscDispatch(ch);
this.EnterGround();
}
}
/// <summary>
/// - Processes a character event into an Action that occurs while in the DcsPassThrough state.
/// Events in this state will:
/// 1. Pass through if character is valid.
/// 2. Ignore everything else.
/// The termination state is handled outside when an ESC is seen.
/// </summary>
/// <param name="ch"></param>
private void EventDCSPassThrough(byte ch)
{
if (ASCIIChars.IsC0Code(ch) || ASCIIChars.IsDCSPassThroughValid(ch))
{
if (!this.dcsStringHandler(ch))
{
this.EnterDCSIgnore();
}
}
else
{
this.ActionIgnore(ch);
}
}
/// <summary>
/// - Handle the two-character termination of a OSC sequence.
/// Events in this state will:
/// 1. Trigger the OSC action associated with the param on an OscTerminator
/// 2. Otherwise treat this as a normal escape character event.
/// </summary>
/// <param name="ch"></param>
private void EventOSCTermination(byte ch)
{
if (ASCIIChars.IsStringTermination(ch))
{
// OSC状态下出现了ESC后，后面紧跟着ST字符，说明是OSC状态结束了
this.ActionOSCDispatch(ch);
this.EnterGround();
}
else
{
// OSC状态下出现了ESC后，后面没有ST字符，说明要Cancel OSC状态并直接进入ESC模式
this.EnterEscape();
this.EventEscape(ch);
}
}
/// <summary>
/// 收集CSI状态下的Parameter字符
/// - Triggers the Param action to indicate that the state machine should store this character as a part of a parameter
/// to a control sequence.
/// </summary>
/// <param name="ch"></param>
private void ActionParam(byte ch)
{
if (this.parameters.Count == 0)
{
this.parameters.Add(0);
}
if (ASCIIChars.IsParameterDelimiter(ch))
{
this.parameters.Add(0);
}
else
{
int last = this.parameters.Last();
this.parameters[this.parameters.Count - 1] = this.AccumulateTo(ch, last);
}
}
/// <summary>
/// - Processes a character event into an Action that occurs while in the DcsIntermediate state.
/// Events in this state will:
/// 1. Ignore C0 control characters
/// 2. Ignore Delete characters
/// 3. Collect intermediate data.
/// 4. Begin to ignore all remaining intermediates when an invalid character is detected (DcsIgnore)
/// 5. Dispatch the Final character in preparation for parsing the data string
/// </summary>
/// <param name="ch"></param>
private void EventDCSIntermediate(byte ch)
{
if (ASCIIChars.IsC0Code(ch))
{
this.ActionIgnore(ch);
}
else if (ASCIIChars.IsDelete(ch))
{
this.ActionIgnore(ch);
}
else if (ASCIIChars.IsIntermediate(ch))
{
this.ActionCollect(ch);
}
else if (ASCIIChars.IsIntermediateInvalid(ch))
{
this.EnterDCSIgnore();
}
else
{
this.ActionDCSDispatch(ch);
}
}
/// <summary>
/// Processes a character event into an Action that occurs while in the CsiIgnore state.
/// Events in this state will:
/// 1. Execute C0 control characters
/// 2. Ignore Delete characters
/// 3. Collect Intermediate characters
/// 4. Begin to ignore all remaining parameters when an invalid character is detected (CsiIgnore)
/// 5. Return to Ground
/// </summary>
/// <param name="ch"></param>
private void EventCSIIgnore(byte ch)
{
if (ASCIIChars.IsC0Code(ch))
{
this.ActionExecute(ch);
}
else if (ASCIIChars.IsDelete(ch))
{
this.ActionIgnore(ch);
}
else if (ASCIIChars.IsIntermediate(ch))
{
this.ActionIgnore(ch);
}
else if (ASCIIChars.IsIntermediateInvalid(ch))
{
this.ActionIgnore(ch);
}
else
{
this.EnterGround();
}
}
/// <summary>
/// 进入到了OSC状态，开始解析OSC命令
/// </summary>
/// <param name="ch"></param>
private void EventOSCParam(byte ch)
{
if (ASCIIChars.IsOSCTerminator(ch))
{
// OSC状态下出现了BEL结束符
// 参考terminal的做法，进入Ground状态
this.EnterGround();
}
else if (ASCIIChars.IsNumericParamValue(ch))
{
// OSC状态下的数字，收集起来
this.ActionOSCParam(ch);
}
else if (ASCIIChars.IsOSCDelimiter(ch))
{
// OSC状态下出现了分隔符，说明要开始收集字符串了
this.EnterOSCString();
}
else
{
// 其他所有的字符都忽略
this.ActionIgnore(ch);
}
}
/// <summary>
/// - Processes a character event into an Action that occurs while in the Vt52Param state.
/// Events in this state will:
/// 1. Execute C0 control characters
/// 2. Ignore Delete characters
/// 3. Store exactly two parameter characters
/// 4. Dispatch a control sequence with parameters for action (always Direct Cursor Address)
/// </summary>
/// <param name="ch"></param>
private void EventVt52Param(byte ch)
{
if (ASCIIChars.IsC0Code(ch))
{
this.ActionExecute(ch);
}
else if (ASCIIChars.IsDelete(ch))
{
this.ActionIgnore(ch);
}
else
{
this.parameters.Add(ch);
if (this.parameters.Count == 2)
{
// The command character is processed before the parameter values,
// but it will always be 'Y', the Direct Cursor Address command.
// 到了这里说明Y指令的参数收集完了，可以执行了，因为Y指令是移动光标指令，有且只有两个参数
this.ActionVt52EscDispatch((byte)'Y');
this.EnterGround();
}
}
}
/// <summary>
/// 解析终端字节流
/// </summary>
/// <param name="bytes">要解析的字节流</param>
public void ProcessCharacters(byte[] bytes)
{
int length = bytes.Length;
for (int i = 0; i < length; i++)
{
byte ch = bytes[i];
// 在OSCString的状态下，ESC转义字符可以用作OSC状态的结束符，所以在这里不进入ESC状态
if (ASCIIChars.IsEscape(ch) && this.state != VTStates.OSCString)
{
this.EnterEscape();
}
else
{
switch (this.state)
{
case VTStates.Ground:
{
this.EventGround(ch);
break;
}
case VTStates.Escape:
{
this.EventEscape(ch);
break;
}
case VTStates.EscapeIntermediate:
{
this.EventEscapeIntermediate(ch);
break;
}
case VTStates.OSCParam:
{
this.EventOSCParam(ch);
break;
}
case VTStates.OSCString:
{
this.EventOSCString(ch);
break;
}
case VTStates.OSCTermination:
{
this.EventOSCTermination(ch);
break;
}
case VTStates.CSIEntry:
{
this.EventCSIEntry(ch);
break;
}
case VTStates.CSIIntermediate:
{
this.EventCSIIntermediate(ch);
break;
}
case VTStates.CSIIgnore:
{
this.EventCSIIgnore(ch);
break;
}
case VTStates.CSIParam:
{
this.EventCSIParam(ch);
break;
}
case VTStates.DCSEntry:
{
this.EventDCSEntry(ch);
break;
}
case VTStates.DCSIgnore:
{
this.EventDCSIgnore(ch);
break;
}
case VTStates.DCSIntermediate:
{
this.EventDCSIntermediate(ch);
break;
}
case VTStates.DCSParam:
{
this.EventDCSParam(ch);
break;
}
case VTStates.DCSPassthrough:
{
this.EventDCSPassThrough(ch);
break;
}
case VTStates.Vt52Param:
{
this.EventVt52Param(ch);
break;
}
}
}
}
}