VirtuosoChris/QuakeConsoleWidget.h

## QuakeConsoleWidget.h
//
//  ConsoleWidget.h
//
//  Created by VirtuosoChris on 8/17/20.
//  Forked from Example Console code in IMGUI samples
//  https://github.com/ocornut/imgui/blob/master/imgui_demo.cpp

#ifndef ConsoleWidget_h
#define ConsoleWidget_h

#include <Depends/VirtuosoConsole/GameConsole.h>
#include <Depends/VirtuosoConsole/GameConsole.cpp>

#include <Depends/VirtuosoConsole/BaseLog.h>

#include <Depends/VirtuosoConsole/SimpleLog.h>


#include <set>

struct ConsoleBuf : public std::streambuf
{
    std::vector<std::string> items;

    struct membuf: std::streambuf
    {
        membuf(const char* begin, const char* end)
        {
             this->setg((char*)begin, (char*)begin, (char*)end);
        }
    };

    ConsoleBuf()
    {
        items.push_back("");
    }

    std::string& curStr()
    {
        int idx = items.size()-1;
        return items[idx];
    }

    int overflow(int c)
    {
        if (c != EOF)
        {
            if (c == '\n')
            {
                items.push_back("");
            }
            else
            {
                 curStr() +=(char)c;
            }
        }
        return c;
    }

    std::streamsize xsputn ( const char * s, std::streamsize n )
    {
        membuf mb(s, s + n);

        std::istream ib(&mb);

        while (!ib.eof())
        {
            std::string ln;
            std::getline(ib, ln);
            curStr()+=ln;

            if (!ib.eof())
            {
                items.push_back("");
            }
        }

        return n;
    }
};


struct ConsoleWidget : public Virtuoso::GameConsole, public Virtuoso::BaseLog, public std::ostream
{
    ConsoleBuf strb;
    char                  InputBuf[256];
    int                   HistoryPos;    // -1: new line, 0..History.Size-1 browsing history.
    ImGuiTextFilter       Filter;
    bool                  AutoScroll;
    bool                  ScrollToBottom;

    virtual std::ostream& status()
    {
        return *this;
    }

    virtual std::ostream& error()
    {
        return (*this)<<"[error] : ";
    }

    virtual std::ostream& echo()
    {
        return (*this)<<"> ";
    }

    virtual std::ostream& warning()
    {
         return (*this)<<"[warning] : ";
    }

    ConsoleWidget() : std::ostream(&strb)
    {
        ClearLog();
        memset(InputBuf, 0, sizeof(InputBuf));
        HistoryPos = -1;

        // "CLASSIFY" is here to provide the test case where "C"+[tab] completes to "CL" and display multiple matches.

        AutoScroll = true;
        ScrollToBottom = false;
    }
    ~ConsoleWidget()
    {
    }

    // Portable helpers
    static int   Stricmp(const char* s1, const char* s2)         { int d; while ((d = toupper(*s2) - toupper(*s1)) == 0 && *s1) { s1++; s2++; } return d; }
    static int   Strnicmp(const char* s1, const char* s2, int n) { int d = 0; while (n > 0 && (d = toupper(*s2) - toupper(*s1)) == 0 && *s1) { s1++; s2++; n--; } return d; }
    static char* Strdup(const char* s)                           { size_t len = strlen(s) + 1; void* buf = malloc(len); IM_ASSERT(buf); return (char*)memcpy(buf, (const void*)s, len); }
    static void  Strtrim(char* s)                                { char* str_end = s + strlen(s); while (str_end > s && str_end[-1] == ' ') str_end--; *str_end = 0; }

    void ClearLog()
    {
        strb.items.clear();
        strb.items.push_back("");
    }

    void optionsMenu()
    {
        ImGui::Checkbox("Auto-scroll", &AutoScroll);
    }

    void Draw(const char* title, bool* p_open)
    {
        ImGui::SetNextWindowSize(ImVec2(520, 600), ImGuiCond_FirstUseEver);
        if (!ImGui::Begin(title, p_open))
        {
            ImGui::End();
            return;
        }

        // As a specific feature guaranteed by the library, after calling Begin() the last Item represent the title bar.
        // So e.g. IsItemHovered() will return true when hovering the title bar.
        // Here we create a context menu only available from the title bar.
        if (ImGui::BeginPopupContextItem())
        {
            if (ImGui::MenuItem("Close Console"))
                *p_open = false;
            ImGui::EndPopup();
        }

        ImGui::TextWrapped("Enter 'HELP' for help, press TAB to use text completion.");

        // TODO: display items starting from the bottom

        if (ImGui::SmallButton("Clear")){ ClearLog(); } ImGui::SameLine();

        bool copy_to_clipboard = ImGui::SmallButton("Copy");

        ImGui::Separator();

        // Options menu
        if (ImGui::BeginPopup("Options"))
        {
            optionsMenu();
            ImGui::EndPopup();
        }

        // Options, Filter
        if (ImGui::Button("Options"))
            ImGui::OpenPopup("Options");
        ImGui::SameLine();
        Filter.Draw("Filter (\"incl,-excl\") (\"error\")", 180);
        ImGui::Separator();

        // Reserve enough left-over height for 1 separator + 1 input text
        const float footer_height_to_reserve = ImGui::GetStyle().ItemSpacing.y + ImGui::GetFrameHeightWithSpacing();
        ImGui::BeginChild("ScrollingRegion", ImVec2(0, -footer_height_to_reserve), false, ImGuiWindowFlags_HorizontalScrollbar);
        if (ImGui::BeginPopupContextWindow())
        {
            if (ImGui::Selectable("Clear")) ClearLog();
            ImGui::EndPopup();
        }

        // Display every line as a separate entry so we can change their color or add custom widgets.
        // If you only want raw text you can use ImGui::TextUnformatted(log.begin(), log.end());
        // NB- if you have thousands of entries this approach may be too inefficient and may require user-side clipping
        // to only process visible items. The clipper will automatically measure the height of your first item and then
        // "seek" to display only items in the visible area.
        // To use the clipper we can replace your standard loop:
        //      for (int i = 0; i < Items.Size; i++)
        //   With:
        //      ImGuiListClipper clipper(Items.Size);
        //      while (clipper.Step())
        //         for (int i = clipper.DisplayStart; i < clipper.DisplayEnd; i++)
        // - That your items are evenly spaced (same height)
        // - That you have cheap random access to your elements (you can access them given their index,
        //   without processing all the ones before)
        // You cannot this code as-is if a filter is active because it breaks the 'cheap random-access' property.
        // We would need random-access on the post-filtered list.
        // A typical application wanting coarse clipping and filtering may want to pre-compute an array of indices
        // or offsets of items that passed the filtering test, recomputing this array when user changes the filter,
        // and appending newly elements as they are inserted. This is left as a task to the user until we can manage
        // to improve this example code!
        // If your items are of variable height:
        // - Split them into same height items would be simpler and facilitate random-seeking into your list.
        // - Consider using manual call to IsRectVisible() and skipping extraneous decoration from your items.
        ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(4, 1)); // Tighten spacing
        if (copy_to_clipboard)
            ImGui::LogToClipboard();
        for (int i = 0; i < strb.items.size(); i++)
        {
            const char* item = strb.items[i].c_str();
            if (!Filter.PassFilter(item))
                continue;

            // Normally you would store more information in your item than just a string.
            // (e.g. make Items[] an array of structure, store color/type etc.)
            ImVec4 color;
            bool has_color = false;
            if (strstr(item, "[error]"))
            {
                color = ImVec4(2.0f, 0.2f, 0.2f, 1.0f); has_color = true;
            }
            else if (strncmp(item, "# ", 2) == 0)
            {
                color = ImVec4(1.0f, 0.8f, 0.6f, 1.0f); has_color = true;
            }
            if (strstr(item, "[warning]"))
            {
                color = ImVec4(1.0f, 1.0f, 0.0f, 1.0f); has_color = true;
            }
            if (strstr(item, "> "))
            {
                 color = ImVec4(1.0f, 0.8f, 0.6f, 1.0f); has_color = true;
            }

            if (has_color)
                ImGui::PushStyleColor(ImGuiCol_Text, color);
            ImGui::TextUnformatted(item);
            if (has_color)
                ImGui::PopStyleColor();
        }
        if (copy_to_clipboard)
            ImGui::LogFinish();

        if (ScrollToBottom || (AutoScroll && ImGui::GetScrollY() >= ImGui::GetScrollMaxY()))
            ImGui::SetScrollHereY(1.0f);
        ScrollToBottom = false;

        ImGui::PopStyleVar();
        ImGui::EndChild();
        ImGui::Separator();

        // Command-line
        bool reclaim_focus = false;
        ImGuiInputTextFlags input_text_flags = ImGuiInputTextFlags_EnterReturnsTrue | ImGuiInputTextFlags_CallbackCompletion | ImGuiInputTextFlags_CallbackHistory;
        if (ImGui::InputText("Input", InputBuf, IM_ARRAYSIZE(InputBuf), input_text_flags, &TextEditCallbackStub, (void*)this))
        {
            char* s = InputBuf;
            Strtrim(s);
            if (s[0])
                ExecCommand(s);
            strcpy(s, "");
            reclaim_focus = true;
        }

        // Auto-focus on window apparition
        ImGui::SetItemDefaultFocus();
        if (reclaim_focus)
            ImGui::SetKeyboardFocusHere(-1); // Auto focus previous widget

        ImGui::End();
    }

    void ExecCommand(const char* command_line)
    {
        // Insert into history. First find match and delete it so it can be pushed to the back.
        // This isn't trying to be smart or optimal.
        HistoryPos = -1;

        commandExecute(command_line, *this);

        // On command input, we scroll to bottom even if AutoScroll==false
        ScrollToBottom = true;
    }

    // In C++11 you'd be better off using lambdas for this sort of forwarding callbacks
    static int TextEditCallbackStub(ImGuiInputTextCallbackData* data)
    {
        ConsoleWidget* console = (ConsoleWidget*)data->UserData;
        return console->TextEditCallback(data);
    }

    int TextEditCallback(ImGuiInputTextCallbackData* data)
    {
        switch (data->EventFlag)
        {
            case ImGuiInputTextFlags_CallbackCompletion:
            {
                // Example of TEXT COMPLETION

                // Locate beginning of current word
                const char* word_end = data->Buf + data->CursorPos;
                const char* word_start = word_end;
                while (word_start > data->Buf)
                {
                    const char c = word_start[-1];
                    if (c == ' ' || c == '\t' || c == ',' || c == ';')
                        break;
                    word_start--;
                }

                // Build a list of candidates
                ImVector<const char*> candidates;
                //for (int i = 0; i < Commands.Size; i++)
                for (auto it = commandTable.begin(); it != commandTable.end(); it++)
                {
                    const char* cmd = it->first.c_str();
                    if (Strnicmp(cmd, word_start, (int)(word_end - word_start)) == 0)
                    {
                        candidates.push_back(cmd);
                    }
                }

                if (candidates.Size == 0)
                {
                    // No match
                    //AddLog("No match for %.*s, , word_start);
                    (*this)<<"No match for ";
                    (*this)<<(int)(word_end - word_start);
                    (*this)<<' '<<word_start;
                    (*this)<<"!\n";
                }
                else if (candidates.Size == 1)
                {
                    // Single match. Delete the beginning of the word and replace it entirely so we've got nice casing.
                    data->DeleteChars((int)(word_start - data->Buf), (int)(word_end - word_start));
                    data->InsertChars(data->CursorPos, candidates[0]);
                    data->InsertChars(data->CursorPos, " ");
                }
                else
                {
                    // Multiple matches. Complete as much as we can..
                    // So inputing "C"+Tab will complete to "CL" then display "CLEAR" and "CLASSIFY" as matches.
                    int match_len = (int)(word_end - word_start);
                    for (;;)
                    {
                        int c = 0;
                        bool all_candidates_matches = true;
                        for (int i = 0; i < candidates.Size && all_candidates_matches; i++)
                            if (i == 0)
                                c = toupper(candidates[i][match_len]);
                            else if (c == 0 || c != toupper(candidates[i][match_len]))
                                all_candidates_matches = false;
                        if (!all_candidates_matches)
                            break;
                        match_len++;
                    }

                    if (match_len > 0)
                    {
                        data->DeleteChars((int)(word_start - data->Buf), (int)(word_end - word_start));
                        data->InsertChars(data->CursorPos, candidates[0], candidates[0] + match_len);
                    }

                    // List matches
                    (*this)<<"Possible matches:\n";
                    for (int i = 0; i < candidates.Size; i++)
                        (*this)<<"- "<<candidates[i]<<'\n';
                }

                break;
            }
            case ImGuiInputTextFlags_CallbackHistory:
            {
                // Example of HISTORY
                const int prev_history_pos = HistoryPos;
                if (data->EventKey == ImGuiKey_UpArrow)
                {
                    if (HistoryPos == -1)
                        HistoryPos = history_buffer.size() - 1;
                    else if (HistoryPos > 0)
                        HistoryPos--;
                }
                else if (data->EventKey == ImGuiKey_DownArrow)
                {
                    if (HistoryPos != -1)
                        if (++HistoryPos >= history_buffer.size())
                            HistoryPos = -1;
                }

                // A better implementation would preserve the data on the current input line along with cursor position.
                if (prev_history_pos != HistoryPos)
                {
                    const char* history_str = (HistoryPos >= 0) ? history_buffer[HistoryPos].c_str() : "";
                    data->DeleteChars(0, data->BufTextLen);
                    data->InsertChars(0, history_str);
                }
            }
        }
        return 0;
    }
};

static void ShowExampleAppConsole(bool* p_open)
{
    static ConsoleWidget console;
    console.Draw("Example: Console", p_open);
}

#endif /* ConsoleWidget_h */
	//
	// ConsoleWidget.h
	//
	// Created by VirtuosoChris on 8/17/20.
	// Forked from Example Console code in IMGUI samples
	// https://github.com/ocornut/imgui/blob/master/imgui_demo.cpp

	#ifndef ConsoleWidget_h
	#define ConsoleWidget_h

	#include <Depends/VirtuosoConsole/GameConsole.h>
	#include <Depends/VirtuosoConsole/GameConsole.cpp>

	#include <Depends/VirtuosoConsole/BaseLog.h>

	#include <Depends/VirtuosoConsole/SimpleLog.h>


	#include <set>

	struct ConsoleBuf : public std::streambuf
	{
	std::vector<std::string> items;

	struct membuf: std::streambuf
	{
	membuf(const char* begin, const char* end)
	{
	this->setg((char)begin, (char)begin, (char*)end);
	}
	};

	ConsoleBuf()
	{
	items.push_back("");
	}

	std::string& curStr()
	{
	int idx = items.size()-1;
	return items[idx];
	}

	int overflow(int c)
	{
	if (c != EOF)
	{
	if (c == '\n')
	{
	items.push_back("");
	}
	else
	{
	curStr() +=(char)c;
	}
	}
	return c;
	}

	std::streamsize xsputn ( const char * s, std::streamsize n )
	{
	membuf mb(s, s + n);

	std::istream ib(&mb);

	while (!ib.eof())
	{
	std::string ln;
	std::getline(ib, ln);
	curStr()+=ln;

	if (!ib.eof())
	{
	items.push_back("");
	}
	}

	return n;
	}
	};


	struct ConsoleWidget : public Virtuoso::GameConsole, public Virtuoso::BaseLog, public std::ostream
	{
	ConsoleBuf strb;
	char InputBuf[256];
	int HistoryPos; // -1: new line, 0..History.Size-1 browsing history.
	ImGuiTextFilter Filter;
	bool AutoScroll;
	bool ScrollToBottom;

	virtual std::ostream& status()
	{
	return *this;
	}

	virtual std::ostream& error()
	{
	return (*this)<<"[error] : ";
	}

	virtual std::ostream& echo()
	{
	return (*this)<<"> ";
	}

	virtual std::ostream& warning()
	{
	return (*this)<<"[warning] : ";
	}

	ConsoleWidget() : std::ostream(&strb)
	{
	ClearLog();
	memset(InputBuf, 0, sizeof(InputBuf));
	HistoryPos = -1;

	// "CLASSIFY" is here to provide the test case where "C"+[tab] completes to "CL" and display multiple matches.

	AutoScroll = true;
	ScrollToBottom = false;
	}
	~ConsoleWidget()
	{
	}

	// Portable helpers
	static int Stricmp(const char* s1, const char* s2) { int d; while ((d = toupper(s2) - toupper(s1)) == 0 && *s1) { s1++; s2++; } return d; }
	static int Strnicmp(const char* s1, const char* s2, int n) { int d = 0; while (n > 0 && (d = toupper(s2) - toupper(s1)) == 0 && *s1) { s1++; s2++; n--; } return d; }
	static char* Strdup(const char* s) { size_t len = strlen(s) + 1; void* buf = malloc(len); IM_ASSERT(buf); return (char)memcpy(buf, (const void)s, len); }
	static void Strtrim(char* s) { char* str_end = s + strlen(s); while (str_end > s && str_end[-1] == ' ') str_end--; *str_end = 0; }

	void ClearLog()
	{
	strb.items.clear();
	strb.items.push_back("");
	}

	void optionsMenu()
	{
	ImGui::Checkbox("Auto-scroll", &AutoScroll);
	}

	void Draw(const char* title, bool* p_open)
	{
	ImGui::SetNextWindowSize(ImVec2(520, 600), ImGuiCond_FirstUseEver);
	if (!ImGui::Begin(title, p_open))
	{
	ImGui::End();
	return;
	}

	// As a specific feature guaranteed by the library, after calling Begin() the last Item represent the title bar.
	// So e.g. IsItemHovered() will return true when hovering the title bar.
	// Here we create a context menu only available from the title bar.
	if (ImGui::BeginPopupContextItem())
	{
	if (ImGui::MenuItem("Close Console"))
	*p_open = false;
	ImGui::EndPopup();
	}

	ImGui::TextWrapped("Enter 'HELP' for help, press TAB to use text completion.");

	// TODO: display items starting from the bottom

	if (ImGui::SmallButton("Clear")){ ClearLog(); } ImGui::SameLine();

	bool copy_to_clipboard = ImGui::SmallButton("Copy");

	ImGui::Separator();

	// Options menu
	if (ImGui::BeginPopup("Options"))
	{
	optionsMenu();
	ImGui::EndPopup();
	}

	// Options, Filter
	if (ImGui::Button("Options"))
	ImGui::OpenPopup("Options");
	ImGui::SameLine();
	Filter.Draw("Filter (\"incl,-excl\") (\"error\")", 180);
	ImGui::Separator();

	// Reserve enough left-over height for 1 separator + 1 input text
	const float footer_height_to_reserve = ImGui::GetStyle().ItemSpacing.y + ImGui::GetFrameHeightWithSpacing();
	ImGui::BeginChild("ScrollingRegion", ImVec2(0, -footer_height_to_reserve), false, ImGuiWindowFlags_HorizontalScrollbar);
	if (ImGui::BeginPopupContextWindow())
	{
	if (ImGui::Selectable("Clear")) ClearLog();
	ImGui::EndPopup();
	}

	// Display every line as a separate entry so we can change their color or add custom widgets.
	// If you only want raw text you can use ImGui::TextUnformatted(log.begin(), log.end());
	// NB- if you have thousands of entries this approach may be too inefficient and may require user-side clipping
	// to only process visible items. The clipper will automatically measure the height of your first item and then
	// "seek" to display only items in the visible area.
	// To use the clipper we can replace your standard loop:
	// for (int i = 0; i < Items.Size; i++)
	// With:
	// ImGuiListClipper clipper(Items.Size);
	// while (clipper.Step())
	// for (int i = clipper.DisplayStart; i < clipper.DisplayEnd; i++)
	// - That your items are evenly spaced (same height)
	// - That you have cheap random access to your elements (you can access them given their index,
	// without processing all the ones before)
	// You cannot this code as-is if a filter is active because it breaks the 'cheap random-access' property.
	// We would need random-access on the post-filtered list.
	// A typical application wanting coarse clipping and filtering may want to pre-compute an array of indices
	// or offsets of items that passed the filtering test, recomputing this array when user changes the filter,
	// and appending newly elements as they are inserted. This is left as a task to the user until we can manage
	// to improve this example code!
	// If your items are of variable height:
	// - Split them into same height items would be simpler and facilitate random-seeking into your list.
	// - Consider using manual call to IsRectVisible() and skipping extraneous decoration from your items.
	ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(4, 1)); // Tighten spacing
	if (copy_to_clipboard)
	ImGui::LogToClipboard();
	for (int i = 0; i < strb.items.size(); i++)
	{
	const char* item = strb.items[i].c_str();
	if (!Filter.PassFilter(item))
	continue;

	// Normally you would store more information in your item than just a string.
	// (e.g. make Items[] an array of structure, store color/type etc.)
	ImVec4 color;
	bool has_color = false;
	if (strstr(item, "[error]"))
	{
	color = ImVec4(2.0f, 0.2f, 0.2f, 1.0f); has_color = true;
	}
	else if (strncmp(item, "# ", 2) == 0)
	{
	color = ImVec4(1.0f, 0.8f, 0.6f, 1.0f); has_color = true;
	}
	if (strstr(item, "[warning]"))
	{
	color = ImVec4(1.0f, 1.0f, 0.0f, 1.0f); has_color = true;
	}
	if (strstr(item, "> "))
	{
	color = ImVec4(1.0f, 0.8f, 0.6f, 1.0f); has_color = true;
	}

	if (has_color)
	ImGui::PushStyleColor(ImGuiCol_Text, color);
	ImGui::TextUnformatted(item);
	if (has_color)
	ImGui::PopStyleColor();
	}
	if (copy_to_clipboard)
	ImGui::LogFinish();

	if (ScrollToBottom \|\| (AutoScroll && ImGui::GetScrollY() >= ImGui::GetScrollMaxY()))
	ImGui::SetScrollHereY(1.0f);
	ScrollToBottom = false;

	ImGui::PopStyleVar();
	ImGui::EndChild();
	ImGui::Separator();

	// Command-line
	bool reclaim_focus = false;
	ImGuiInputTextFlags input_text_flags = ImGuiInputTextFlags_EnterReturnsTrue \| ImGuiInputTextFlags_CallbackCompletion \| ImGuiInputTextFlags_CallbackHistory;
	if (ImGui::InputText("Input", InputBuf, IM_ARRAYSIZE(InputBuf), input_text_flags, &TextEditCallbackStub, (void*)this))
	{
	char* s = InputBuf;
	Strtrim(s);
	if (s[0])
	ExecCommand(s);
	strcpy(s, "");
	reclaim_focus = true;
	}

	// Auto-focus on window apparition
	ImGui::SetItemDefaultFocus();
	if (reclaim_focus)
	ImGui::SetKeyboardFocusHere(-1); // Auto focus previous widget

	ImGui::End();
	}

	void ExecCommand(const char* command_line)
	{
	// Insert into history. First find match and delete it so it can be pushed to the back.
	// This isn't trying to be smart or optimal.
	HistoryPos = -1;

	commandExecute(command_line, *this);

	// On command input, we scroll to bottom even if AutoScroll==false
	ScrollToBottom = true;
	}

	// In C++11 you'd be better off using lambdas for this sort of forwarding callbacks
	static int TextEditCallbackStub(ImGuiInputTextCallbackData* data)
	{
	ConsoleWidget* console = (ConsoleWidget*)data->UserData;
	return console->TextEditCallback(data);
	}

	int TextEditCallback(ImGuiInputTextCallbackData* data)
	{
	switch (data->EventFlag)
	{
	case ImGuiInputTextFlags_CallbackCompletion:
	{
	// Example of TEXT COMPLETION

	// Locate beginning of current word
	const char* word_end = data->Buf + data->CursorPos;
	const char* word_start = word_end;
	while (word_start > data->Buf)
	{
	const char c = word_start[-1];
	if (c == ' ' \|\| c == '\t' \|\| c == ',' \|\| c == ';')
	break;
	word_start--;
	}

	// Build a list of candidates
	ImVector<const char*> candidates;
	//for (int i = 0; i < Commands.Size; i++)
	for (auto it = commandTable.begin(); it != commandTable.end(); it++)
	{
	const char* cmd = it->first.c_str();
	if (Strnicmp(cmd, word_start, (int)(word_end - word_start)) == 0)
	{
	candidates.push_back(cmd);
	}
	}

	if (candidates.Size == 0)
	{
	// No match
	//AddLog("No match for %.*s, , word_start);
	(*this)<<"No match for ";
	(*this)<<(int)(word_end - word_start);
	(*this)<<' '<<word_start;
	(*this)<<"!\n";
	}
	else if (candidates.Size == 1)
	{
	// Single match. Delete the beginning of the word and replace it entirely so we've got nice casing.
	data->DeleteChars((int)(word_start - data->Buf), (int)(word_end - word_start));
	data->InsertChars(data->CursorPos, candidates[0]);
	data->InsertChars(data->CursorPos, " ");
	}
	else
	{
	// Multiple matches. Complete as much as we can..
	// So inputing "C"+Tab will complete to "CL" then display "CLEAR" and "CLASSIFY" as matches.
	int match_len = (int)(word_end - word_start);
	for (;;)
	{
	int c = 0;
	bool all_candidates_matches = true;
	for (int i = 0; i < candidates.Size && all_candidates_matches; i++)
	if (i == 0)
	c = toupper(candidates[i][match_len]);
	else if (c == 0 \|\| c != toupper(candidates[i][match_len]))
	all_candidates_matches = false;
	if (!all_candidates_matches)
	break;
	match_len++;
	}

	if (match_len > 0)
	{
	data->DeleteChars((int)(word_start - data->Buf), (int)(word_end - word_start));
	data->InsertChars(data->CursorPos, candidates[0], candidates[0] + match_len);
	}

	// List matches
	(*this)<<"Possible matches:\n";
	for (int i = 0; i < candidates.Size; i++)
	(*this)<<"- "<<candidates[i]<<'\n';
	}

	break;
	}
	case ImGuiInputTextFlags_CallbackHistory:
	{
	// Example of HISTORY
	const int prev_history_pos = HistoryPos;
	if (data->EventKey == ImGuiKey_UpArrow)
	{
	if (HistoryPos == -1)
	HistoryPos = history_buffer.size() - 1;
	else if (HistoryPos > 0)
	HistoryPos--;
	}
	else if (data->EventKey == ImGuiKey_DownArrow)
	{
	if (HistoryPos != -1)
	if (++HistoryPos >= history_buffer.size())
	HistoryPos = -1;
	}

	// A better implementation would preserve the data on the current input line along with cursor position.
	if (prev_history_pos != HistoryPos)
	{
	const char* history_str = (HistoryPos >= 0) ? history_buffer[HistoryPos].c_str() : "";
	data->DeleteChars(0, data->BufTextLen);
	data->InsertChars(0, history_str);
	}
	}
	}
	return 0;
	}
	};

	static void ShowExampleAppConsole(bool* p_open)
	{
	static ConsoleWidget console;
	console.Draw("Example: Console", p_open);
	}

	#endif /* ConsoleWidget_h */