/*
 * Copyright 2003-2006, Haiku, Inc. All Rights Reserved.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *              Stefano Ceccherini (burton666@libero.it)
 */

// For a deeper understanding of this class, see the BeBook, sez.
// "The Input Server".
// TODO: the bebook says we should highlight in blue/red different "clauses".
// Though it looks like what really matters is the "selection" field in
// the BMessage sent by the input method addon. Have I missed something ?

#include "InlineInput.h"

#include <cstdlib>

struct clause
{
        int32 start;
        int32 end;
};


/*! \brief Constructs a InlineInput object.
        \param messenger The BMessenger of the input server method addon.
*/
BTextView::InlineInput::InlineInput(BMessenger messenger)
        :
        fMessenger(messenger),
        fActive(false),
        fOffset(0),
        fLength(0),
        fSelectionOffset(0),
        fSelectionLength(0),
        fNumClauses(0),
        fClauses(NULL)
{
}


/*! \brief Destructs the object, free the allocated memory.
*/
BTextView::InlineInput::~InlineInput()
{
        ResetClauses();
}


/*! \brief Returns a pointer to the Input Server Method BMessenger
        which requested the transaction.
*/
const BMessenger *
BTextView::InlineInput::Method() const
{
        return &fMessenger;
}


bool
BTextView::InlineInput::IsActive() const
{
        return fActive;
}


void
BTextView::InlineInput::SetActive(bool active)
{
        fActive = active;
}


/*! \brief Return the length of the inputted text.
*/
int32
BTextView::InlineInput::Length() const
{
        return fLength;
}


/*! \brief Sets the length of the text inputted with the input method.
        \param len The length of the text, extracted from the
        B_INPUT_METHOD_CHANGED BMessage.
*/
void
BTextView::InlineInput::SetLength(int32 len)
{
        fLength = len;
}


/*! \brief Returns the offset into the BTextView of the text.
*/
int32
BTextView::InlineInput::Offset() const
{
        return fOffset;
}


/*! \brief Sets the offset into the BTextView of the text.
        \param offset The offset where the text has been inserted.
*/
void
BTextView::InlineInput::SetOffset(int32 offset)
{
        fOffset = offset;
}


/*! \brief Returns the length of the selection, if any.
*/
int32
BTextView::InlineInput::SelectionLength() const
{
        return fSelectionLength;
}


/*! \brief Sets the length of the selection.
        \param length The length of the selection.
*/
void
BTextView::InlineInput::SetSelectionLength(int32 length)
{
        fSelectionLength = length;
}


/*! \brief Returns the offset into the method string of the selection.
*/
int32
BTextView::InlineInput::SelectionOffset() const
{
        return fSelectionOffset;
}


/*! \brief Sets the offset into the method string of the selection.
        \param offset The offset where the selection starts.
*/
void
BTextView::InlineInput::SetSelectionOffset(int32 offset)
{
        fSelectionOffset = offset;
}


/*! \brief Adds a clause (see "The Input Server" sez. for details).
        \param start The offset into the string where the clause starts.
        \param end The offset into the string where the clause finishes.
*/
bool
BTextView::InlineInput::AddClause(int32 start, int32 end)
{
        void *newData = realloc(fClauses, (fNumClauses + 1) * sizeof(clause));
        if (newData == NULL)
                return false;

        fClauses = (clause *)newData;
        fClauses[fNumClauses].start = start;
        fClauses[fNumClauses].end = end;
        fNumClauses++;
        return true;
}


/*! \brief Gets the clause at the given index.
        \param index The index of the clause to get.
        \param start A pointer to an integer which will contain the clause's start offset.
        \param end A pointer to an integer which will contain the clause's end offset.
        \return \c true if the clause exists, \c false if not.
*/
bool
BTextView::InlineInput::GetClause(int32 index, int32 *start, int32 *end) const
{
        bool result = false;
        if (index >= 0 && index < fNumClauses) {
                result = true;
                clause *clause = &fClauses[index];
                if (start)
                        *start = clause->start;
                if (end)
                        *end = clause->end;
        }
        
        return result;
}


int32
BTextView::InlineInput::CountClauses() const
{
        return fNumClauses;
}


/*! \brief Deletes any added clause.
*/
void
BTextView::InlineInput::ResetClauses()
{
        fNumClauses = 0;
        free(fClauses);
        fClauses = NULL;
}