/// <summary>
/// Builds an Answer String from the Specified FsdStatus Object
/// </summary>
/// <param name="fsdStatus"></param>
/// <returns></returns>
public ReadOnlySpan <byte> BuildAnswerString(FsdStatus fsdStatus)
{
using var result = new MemoryStream(fsdStatus.Fields.Sum(field => field.Name.Length + field.Value.Length + 4));
foreach (var field in fsdStatus.Fields)
{
result.Write(Encoding.ASCII.GetBytes($"{field.Name}={field.Value}\0"));
}
result.WriteByte(0);
return(result.ToArray());
}
/// <summary>
/// Parses through the template looking for leading ANSI formatting on field specifications
/// </summary>
/// <param name="template"></param>
/// <param name="status"></param>
public void GetFieldAnsi(ReadOnlySpan <byte> template, FsdStatus status)
{
var currentField = 0;
var foundFieldCharacter = 0xFF;
for (var i = 0; i < template.Length; i++)
{
var c = template[i];
//If it's the character we previously found, keep going
if (c == foundFieldCharacter)
{
continue;
}
//We're past the field now, reset the character
foundFieldCharacter = '\xFF';
//If it's a new line, increment Y and set X back to -1
if (c == '\r')
{
continue;
}
//If we're not in a field definition, keep moving
if (c != '?' && c != '$' && c != '!')
{
continue;
}
//Found a field definition character, check to see if the next character is the same
if (template[i + 1] != c)
{
continue;
}
//Assume the ANSI format specification is within the first 10 characters
var extractedAnsi = ExtractFieldAnsi(template.Slice(i - 10, 10));
//Error Fields are their own special little snowflakes
if (c == '!')
{
status.ErrorField.FieldAnsi = extractedAnsi;
}
else
{
status.Fields[currentField].FieldAnsi = extractedAnsi;
currentField++;
}
//Set our Position
foundFieldCharacter = c;
}
}
/// <summary>
/// Determines the X,Y coordinates of specified template fields by stripping ANSI from the field template
/// and parsing each character, each new line increments Y and sets X back to 1.
///
/// Note: X,Y for ANSI starts at 1,1 being the top left of the terminal (not 0,0)
/// </summary>
/// <param name="template"></param>
/// <param name="status"></param>
public void GetFieldPositions(ReadOnlySpan <byte> template, FsdStatus status)
{
//Get Template and Strip out ANSI Characters
var templateString = Encoding.ASCII.GetString(StripAnsi(template));
var currentY = 1; //ANSI x/y positions are 1 based, so first loop these will be 1,1
var currentX = 0;
var currentField = 0;
var currentFieldLength = 0;
var foundFieldCharacter = '\xFF';
for (var i = 0; i < templateString.Length; i++)
{
var c = templateString[i];
//Increment the X Position
currentX++;
//If it's the character we previously found, keep going
if (c == foundFieldCharacter)
{
currentFieldLength++;
continue;
}
//If we're past it, and the previous field Character wasn't the default, mark the length
if (foundFieldCharacter != '\xFF')
{
//Special Case for Error Field
if (foundFieldCharacter == '!')
{
status.ErrorField.FieldLength = currentFieldLength + 1;
}
else
{
//Standard Fields
status.Fields[currentField - 1].FieldLength = currentFieldLength + 1;
}
currentFieldLength = 0;
}
//We're past the field now, reset the character
foundFieldCharacter = '\xFF';
//If it's a new line, increment Y and set X back to -1
if (c == '\n')
{
currentY++;
currentX = 0;
continue;
}
if (c != '?' && c != '$' && c != '!')
{
continue;
}
//If the next character is a known control character, then we're in a field definition
switch (templateString[i + 1])
{
case '?':
case '$':
case '!':
break;
default:
//Otherwise keep searching
continue;
}
//Define the field based on the field specification character used
switch (c)
{
case '!': //Error Message Field
//Add a new field for the Error, as it's not included in the Field Spec
status.ErrorField = new FsdFieldSpec {
FsdFieldType = EnumFsdFieldType.Error, X = currentX, Y = currentY
};
foundFieldCharacter = c;
continue;
case '$': //Numeric Field
status.Fields[currentField].FsdFieldType = EnumFsdFieldType.Numeric;
status.Fields[currentField].X = currentX;
status.Fields[currentField].Y = currentY;
break;
default: //Text or Multiple Choice
status.Fields[currentField].X = currentX;
status.Fields[currentField].Y = currentY;
break;
}
currentField++;
foundFieldCharacter = c;
}
}