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+// [ImGui] this is a slightly modified version of stb_truetype.h 1.9. Those changes would need to be pushed into nothings/sb
+// [ImGui] - fixed linestart handler when over last character of multi-line buffer + simplified existing code (#588, #815)
+// [ImGui] - fixed a state corruption/crash bug in stb_text_redo and stb_textedit_discard_redo (#715)
+// [ImGui] - fixed a crash bug in stb_textedit_discard_redo (#681)
+// [ImGui] - fixed some minor warnings
+
+// stb_textedit.h - v1.9 - public domain - Sean Barrett
+// Development of this library was sponsored by RAD Game Tools
+//
+// This C header file implements the guts of a multi-line text-editing
+// widget; you implement display, word-wrapping, and low-level string
+// insertion/deletion, and stb_textedit will map user inputs into
+// insertions & deletions, plus updates to the cursor position,
+// selection state, and undo state.
+//
+// It is intended for use in games and other systems that need to build
+// their own custom widgets and which do not have heavy text-editing
+// requirements (this library is not recommended for use for editing large
+// texts, as its performance does not scale and it has limited undo).
+//
+// Non-trivial behaviors are modelled after Windows text controls.
+//
+//
+// LICENSE
+//
+// This software is dual-licensed to the public domain and under the following
+// license: you are granted a perpetual, irrevocable license to copy, modify,
+// publish, and distribute this file as you see fit.
+//
+//
+// DEPENDENCIES
+//
+// Uses the C runtime function 'memmove', which you can override
+// by defining STB_TEXTEDIT_memmove before the implementation.
+// Uses no other functions. Performs no runtime allocations.
+//
+//
+// VERSION HISTORY
+//
+// 1.9 (2016-08-27) customizable move-by-word
+// 1.8 (2016-04-02) better keyboard handling when mouse button is down
+// 1.7 (2015-09-13) change y range handling in case baseline is non-0
+// 1.6 (2015-04-15) allow STB_TEXTEDIT_memmove
+// 1.5 (2014-09-10) add support for secondary keys for OS X
+// 1.4 (2014-08-17) fix signed/unsigned warnings
+// 1.3 (2014-06-19) fix mouse clicking to round to nearest char boundary
+// 1.2 (2014-05-27) fix some RAD types that had crept into the new code
+// 1.1 (2013-12-15) move-by-word (requires STB_TEXTEDIT_IS_SPACE )
+// 1.0 (2012-07-26) improve documentation, initial public release
+// 0.3 (2012-02-24) bugfixes, single-line mode; insert mode
+// 0.2 (2011-11-28) fixes to undo/redo
+// 0.1 (2010-07-08) initial version
+//
+// ADDITIONAL CONTRIBUTORS
+//
+// Ulf Winklemann: move-by-word in 1.1
+// Fabian Giesen: secondary key inputs in 1.5
+// Martins Mozeiko: STB_TEXTEDIT_memmove
+//
+// Bugfixes:
+// Scott Graham
+// Daniel Keller
+// Omar Cornut
+//
+// USAGE
+//
+// This file behaves differently depending on what symbols you define
+// before including it.
+//
+//
+// Header-file mode:
+//
+// If you do not define STB_TEXTEDIT_IMPLEMENTATION before including this,
+// it will operate in "header file" mode. In this mode, it declares a
+// single public symbol, STB_TexteditState, which encapsulates the current
+// state of a text widget (except for the string, which you will store
+// separately).
+//
+// To compile in this mode, you must define STB_TEXTEDIT_CHARTYPE to a
+// primitive type that defines a single character (e.g. char, wchar_t, etc).
+//
+// To save space or increase undo-ability, you can optionally define the
+// following things that are used by the undo system:
+//
+// STB_TEXTEDIT_POSITIONTYPE small int type encoding a valid cursor position
+// STB_TEXTEDIT_UNDOSTATECOUNT the number of undo states to allow
+// STB_TEXTEDIT_UNDOCHARCOUNT the number of characters to store in the undo buffer
+//
+// If you don't define these, they are set to permissive types and
+// moderate sizes. The undo system does no memory allocations, so
+// it grows STB_TexteditState by the worst-case storage which is (in bytes):
+//
+// [4 + sizeof(STB_TEXTEDIT_POSITIONTYPE)] * STB_TEXTEDIT_UNDOSTATE_COUNT
+// + sizeof(STB_TEXTEDIT_CHARTYPE) * STB_TEXTEDIT_UNDOCHAR_COUNT
+//
+//
+// Implementation mode:
+//
+// If you define STB_TEXTEDIT_IMPLEMENTATION before including this, it
+// will compile the implementation of the text edit widget, depending
+// on a large number of symbols which must be defined before the include.
+//
+// The implementation is defined only as static functions. You will then
+// need to provide your own APIs in the same file which will access the
+// static functions.
+//
+// The basic concept is that you provide a "string" object which
+// behaves like an array of characters. stb_textedit uses indices to
+// refer to positions in the string, implicitly representing positions
+// in the displayed textedit. This is true for both plain text and
+// rich text; even with rich text stb_truetype interacts with your
+// code as if there was an array of all the displayed characters.
+//
+// Symbols that must be the same in header-file and implementation mode:
+//
+// STB_TEXTEDIT_CHARTYPE the character type
+// STB_TEXTEDIT_POSITIONTYPE small type that a valid cursor position
+// STB_TEXTEDIT_UNDOSTATECOUNT the number of undo states to allow
+// STB_TEXTEDIT_UNDOCHARCOUNT the number of characters to store in the undo buffer
+//
+// Symbols you must define for implementation mode:
+//
+// STB_TEXTEDIT_STRING the type of object representing a string being edited,
+// typically this is a wrapper object with other data you need
+//
+// STB_TEXTEDIT_STRINGLEN(obj) the length of the string (ideally O(1))
+// STB_TEXTEDIT_LAYOUTROW(&r,obj,n) returns the results of laying out a line of characters
+// starting from character #n (see discussion below)
+// STB_TEXTEDIT_GETWIDTH(obj,n,i) returns the pixel delta from the xpos of the i'th character
+// to the xpos of the i+1'th char for a line of characters
+// starting at character #n (i.e. accounts for kerning
+// with previous char)
+// STB_TEXTEDIT_KEYTOTEXT(k) maps a keyboard input to an insertable character
+// (return type is int, -1 means not valid to insert)
+// STB_TEXTEDIT_GETCHAR(obj,i) returns the i'th character of obj, 0-based
+// STB_TEXTEDIT_NEWLINE the character returned by _GETCHAR() we recognize
+// as manually wordwrapping for end-of-line positioning
+//
+// STB_TEXTEDIT_DELETECHARS(obj,i,n) delete n characters starting at i
+// STB_TEXTEDIT_INSERTCHARS(obj,i,c*,n) insert n characters at i (pointed to by STB_TEXTEDIT_CHARTYPE*)
+//
+// STB_TEXTEDIT_K_SHIFT a power of two that is or'd in to a keyboard input to represent the shift key
+//
+// STB_TEXTEDIT_K_LEFT keyboard input to move cursor left
+// STB_TEXTEDIT_K_RIGHT keyboard input to move cursor right
+// STB_TEXTEDIT_K_UP keyboard input to move cursor up
+// STB_TEXTEDIT_K_DOWN keyboard input to move cursor down
+// STB_TEXTEDIT_K_LINESTART keyboard input to move cursor to start of line // e.g. HOME
+// STB_TEXTEDIT_K_LINEEND keyboard input to move cursor to end of line // e.g. END
+// STB_TEXTEDIT_K_TEXTSTART keyboard input to move cursor to start of text // e.g. ctrl-HOME
+// STB_TEXTEDIT_K_TEXTEND keyboard input to move cursor to end of text // e.g. ctrl-END
+// STB_TEXTEDIT_K_DELETE keyboard input to delete selection or character under cursor
+// STB_TEXTEDIT_K_BACKSPACE keyboard input to delete selection or character left of cursor
+// STB_TEXTEDIT_K_UNDO keyboard input to perform undo
+// STB_TEXTEDIT_K_REDO keyboard input to perform redo
+//
+// Optional:
+// STB_TEXTEDIT_K_INSERT keyboard input to toggle insert mode
+// STB_TEXTEDIT_IS_SPACE(ch) true if character is whitespace (e.g. 'isspace'),
+// required for default WORDLEFT/WORDRIGHT handlers
+// STB_TEXTEDIT_MOVEWORDLEFT(obj,i) custom handler for WORDLEFT, returns index to move cursor to
+// STB_TEXTEDIT_MOVEWORDRIGHT(obj,i) custom handler for WORDRIGHT, returns index to move cursor to
+// STB_TEXTEDIT_K_WORDLEFT keyboard input to move cursor left one word // e.g. ctrl-LEFT
+// STB_TEXTEDIT_K_WORDRIGHT keyboard input to move cursor right one word // e.g. ctrl-RIGHT
+// STB_TEXTEDIT_K_LINESTART2 secondary keyboard input to move cursor to start of line
+// STB_TEXTEDIT_K_LINEEND2 secondary keyboard input to move cursor to end of line
+// STB_TEXTEDIT_K_TEXTSTART2 secondary keyboard input to move cursor to start of text
+// STB_TEXTEDIT_K_TEXTEND2 secondary keyboard input to move cursor to end of text
+//
+// Todo:
+// STB_TEXTEDIT_K_PGUP keyboard input to move cursor up a page
+// STB_TEXTEDIT_K_PGDOWN keyboard input to move cursor down a page
+//
+// Keyboard input must be encoded as a single integer value; e.g. a character code
+// and some bitflags that represent shift states. to simplify the interface, SHIFT must
+// be a bitflag, so we can test the shifted state of cursor movements to allow selection,
+// i.e. (STB_TEXTED_K_RIGHT|STB_TEXTEDIT_K_SHIFT) should be shifted right-arrow.
+//
+// You can encode other things, such as CONTROL or ALT, in additional bits, and
+// then test for their presence in e.g. STB_TEXTEDIT_K_WORDLEFT. For example,
+// my Windows implementations add an additional CONTROL bit, and an additional KEYDOWN
+// bit. Then all of the STB_TEXTEDIT_K_ values bitwise-or in the KEYDOWN bit,
+// and I pass both WM_KEYDOWN and WM_CHAR events to the "key" function in the
+// API below. The control keys will only match WM_KEYDOWN events because of the
+// keydown bit I add, and STB_TEXTEDIT_KEYTOTEXT only tests for the KEYDOWN
+// bit so it only decodes WM_CHAR events.
+//
+// STB_TEXTEDIT_LAYOUTROW returns information about the shape of one displayed
+// row of characters assuming they start on the i'th character--the width and
+// the height and the number of characters consumed. This allows this library
+// to traverse the entire layout incrementally. You need to compute word-wrapping
+// here.
+//
+// Each textfield keeps its own insert mode state, which is not how normal
+// applications work. To keep an app-wide insert mode, update/copy the
+// "insert_mode" field of STB_TexteditState before/after calling API functions.
+//
+// API
+//
+// void stb_textedit_initialize_state(STB_TexteditState *state, int is_single_line)
+//
+// void stb_textedit_click(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, float x, float y)
+// void stb_textedit_drag(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, float x, float y)
+// int stb_textedit_cut(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+// int stb_textedit_paste(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, STB_TEXTEDIT_CHARTYPE *text, int len)
+// void stb_textedit_key(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int key)
+//
+// Each of these functions potentially updates the string and updates the
+// state.
+//
+// initialize_state:
+// set the textedit state to a known good default state when initially
+// constructing the textedit.
+//
+// click:
+// call this with the mouse x,y on a mouse down; it will update the cursor
+// and reset the selection start/end to the cursor point. the x,y must
+// be relative to the text widget, with (0,0) being the top left.
+//
+// drag:
+// call this with the mouse x,y on a mouse drag/up; it will update the
+// cursor and the selection end point
+//
+// cut:
+// call this to delete the current selection; returns true if there was
+// one. you should FIRST copy the current selection to the system paste buffer.
+// (To copy, just copy the current selection out of the string yourself.)
+//
+// paste:
+// call this to paste text at the current cursor point or over the current
+// selection if there is one.
+//
+// key:
+// call this for keyboard inputs sent to the textfield. you can use it
+// for "key down" events or for "translated" key events. if you need to
+// do both (as in Win32), or distinguish Unicode characters from control
+// inputs, set a high bit to distinguish the two; then you can define the
+// various definitions like STB_TEXTEDIT_K_LEFT have the is-key-event bit
+// set, and make STB_TEXTEDIT_KEYTOCHAR check that the is-key-event bit is
+// clear.
+//
+// When rendering, you can read the cursor position and selection state from
+// the STB_TexteditState.
+//
+//
+// Notes:
+//
+// This is designed to be usable in IMGUI, so it allows for the possibility of
+// running in an IMGUI that has NOT cached the multi-line layout. For this
+// reason, it provides an interface that is compatible with computing the
+// layout incrementally--we try to make sure we make as few passes through
+// as possible. (For example, to locate the mouse pointer in the text, we
+// could define functions that return the X and Y positions of characters
+// and binary search Y and then X, but if we're doing dynamic layout this
+// will run the layout algorithm many times, so instead we manually search
+// forward in one pass. Similar logic applies to e.g. up-arrow and
+// down-arrow movement.)
+//
+// If it's run in a widget that *has* cached the layout, then this is less
+// efficient, but it's not horrible on modern computers. But you wouldn't
+// want to edit million-line files with it.
+
+
+////////////////////////////////////////////////////////////////////////////
+////////////////////////////////////////////////////////////////////////////
+////
+//// Header-file mode
+////
+////
+
+#ifndef INCLUDE_STB_TEXTEDIT_H
+#define INCLUDE_STB_TEXTEDIT_H
+
+////////////////////////////////////////////////////////////////////////
+//
+// STB_TexteditState
+//
+// Definition of STB_TexteditState which you should store
+// per-textfield; it includes cursor position, selection state,
+// and undo state.
+//
+
+#ifndef STB_TEXTEDIT_UNDOSTATECOUNT
+#define STB_TEXTEDIT_UNDOSTATECOUNT 99
+#endif
+#ifndef STB_TEXTEDIT_UNDOCHARCOUNT
+#define STB_TEXTEDIT_UNDOCHARCOUNT 999
+#endif
+#ifndef STB_TEXTEDIT_CHARTYPE
+#define STB_TEXTEDIT_CHARTYPE int
+#endif
+#ifndef STB_TEXTEDIT_POSITIONTYPE
+#define STB_TEXTEDIT_POSITIONTYPE int
+#endif
+
+typedef struct
+{
+ // private data
+ STB_TEXTEDIT_POSITIONTYPE where;
+ short insert_length;
+ short delete_length;
+ short char_storage;
+} StbUndoRecord;
+
+typedef struct
+{
+ // private data
+ StbUndoRecord undo_rec [STB_TEXTEDIT_UNDOSTATECOUNT];
+ STB_TEXTEDIT_CHARTYPE undo_char[STB_TEXTEDIT_UNDOCHARCOUNT];
+ short undo_point, redo_point;
+ short undo_char_point, redo_char_point;
+} StbUndoState;
+
+typedef struct
+{
+ /////////////////////
+ //
+ // public data
+ //
+
+ int cursor;
+ // position of the text cursor within the string
+
+ int select_start; // selection start point
+ int select_end;
+ // selection start and end point in characters; if equal, no selection.
+ // note that start may be less than or greater than end (e.g. when
+ // dragging the mouse, start is where the initial click was, and you
+ // can drag in either direction)
+
+ unsigned char insert_mode;
+ // each textfield keeps its own insert mode state. to keep an app-wide
+ // insert mode, copy this value in/out of the app state
+
+ /////////////////////
+ //
+ // private data
+ //
+ unsigned char cursor_at_end_of_line; // not implemented yet
+ unsigned char initialized;
+ unsigned char has_preferred_x;
+ unsigned char single_line;
+ unsigned char padding1, padding2, padding3;
+ float preferred_x; // this determines where the cursor up/down tries to seek to along x
+ StbUndoState undostate;
+} STB_TexteditState;
+
+
+////////////////////////////////////////////////////////////////////////
+//
+// StbTexteditRow
+//
+// Result of layout query, used by stb_textedit to determine where
+// the text in each row is.
+
+// result of layout query
+typedef struct
+{
+ float x0,x1; // starting x location, end x location (allows for align=right, etc)
+ float baseline_y_delta; // position of baseline relative to previous row's baseline
+ float ymin,ymax; // height of row above and below baseline
+ int num_chars;
+} StbTexteditRow;
+#endif //INCLUDE_STB_TEXTEDIT_H
+
+
+////////////////////////////////////////////////////////////////////////////
+////////////////////////////////////////////////////////////////////////////
+////
+//// Implementation mode
+////
+////
+
+
+// implementation isn't include-guarded, since it might have indirectly
+// included just the "header" portion
+#ifdef STB_TEXTEDIT_IMPLEMENTATION
+
+#ifndef STB_TEXTEDIT_memmove
+#include <string.h>
+#define STB_TEXTEDIT_memmove memmove
+#endif
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Mouse input handling
+//
+
+// traverse the layout to locate the nearest character to a display position
+static int stb_text_locate_coord(STB_TEXTEDIT_STRING *str, float x, float y)
+{
+ StbTexteditRow r;
+ int n = STB_TEXTEDIT_STRINGLEN(str);
+ float base_y = 0, prev_x;
+ int i=0, k;
+
+ r.x0 = r.x1 = 0;
+ r.ymin = r.ymax = 0;
+ r.num_chars = 0;
+
+ // search rows to find one that straddles 'y'
+ while (i < n) {
+ STB_TEXTEDIT_LAYOUTROW(&r, str, i);
+ if (r.num_chars <= 0)
+ return n;
+
+ if (i==0 && y < base_y + r.ymin)
+ return 0;
+
+ if (y < base_y + r.ymax)
+ break;
+
+ i += r.num_chars;
+ base_y += r.baseline_y_delta;
+ }
+
+ // below all text, return 'after' last character
+ if (i >= n)
+ return n;
+
+ // check if it's before the beginning of the line
+ if (x < r.x0)
+ return i;
+
+ // check if it's before the end of the line
+ if (x < r.x1) {
+ // search characters in row for one that straddles 'x'
+ prev_x = r.x0;
+ for (k=0; k < r.num_chars; ++k) {
+ float w = STB_TEXTEDIT_GETWIDTH(str, i, k);
+ if (x < prev_x+w) {
+ if (x < prev_x+w/2)
+ return k+i;
+ else
+ return k+i+1;
+ }
+ prev_x += w;
+ }
+ // shouldn't happen, but if it does, fall through to end-of-line case
+ }
+
+ // if the last character is a newline, return that. otherwise return 'after' the last character
+ if (STB_TEXTEDIT_GETCHAR(str, i+r.num_chars-1) == STB_TEXTEDIT_NEWLINE)
+ return i+r.num_chars-1;
+ else
+ return i+r.num_chars;
+}
+
+// API click: on mouse down, move the cursor to the clicked location, and reset the selection
+static void stb_textedit_click(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, float x, float y)
+{
+ state->cursor = stb_text_locate_coord(str, x, y);
+ state->select_start = state->cursor;
+ state->select_end = state->cursor;
+ state->has_preferred_x = 0;
+}
+
+// API drag: on mouse drag, move the cursor and selection endpoint to the clicked location
+static void stb_textedit_drag(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, float x, float y)
+{
+ int p = stb_text_locate_coord(str, x, y);
+ if (state->select_start == state->select_end)
+ state->select_start = state->cursor;
+ state->cursor = state->select_end = p;
+}
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Keyboard input handling
+//
+
+// forward declarations
+static void stb_text_undo(STB_TEXTEDIT_STRING *str, STB_TexteditState *state);
+static void stb_text_redo(STB_TEXTEDIT_STRING *str, STB_TexteditState *state);
+static void stb_text_makeundo_delete(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int where, int length);
+static void stb_text_makeundo_insert(STB_TexteditState *state, int where, int length);
+static void stb_text_makeundo_replace(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int where, int old_length, int new_length);
+
+typedef struct
+{
+ float x,y; // position of n'th character
+ float height; // height of line
+ int first_char, length; // first char of row, and length
+ int prev_first; // first char of previous row
+} StbFindState;
+
+// find the x/y location of a character, and remember info about the previous row in
+// case we get a move-up event (for page up, we'll have to rescan)
+static void stb_textedit_find_charpos(StbFindState *find, STB_TEXTEDIT_STRING *str, int n, int single_line)
+{
+ StbTexteditRow r;
+ int prev_start = 0;
+ int z = STB_TEXTEDIT_STRINGLEN(str);
+ int i=0, first;
+
+ if (n == z) {
+ // if it's at the end, then find the last line -- simpler than trying to
+ // explicitly handle this case in the regular code
+ if (single_line) {
+ STB_TEXTEDIT_LAYOUTROW(&r, str, 0);
+ find->y = 0;
+ find->first_char = 0;
+ find->length = z;
+ find->height = r.ymax - r.ymin;
+ find->x = r.x1;
+ } else {
+ find->y = 0;
+ find->x = 0;
+ find->height = 1;
+ while (i < z) {
+ STB_TEXTEDIT_LAYOUTROW(&r, str, i);
+ prev_start = i;
+ i += r.num_chars;
+ }
+ find->first_char = i;
+ find->length = 0;
+ find->prev_first = prev_start;
+ }
+ return;
+ }
+
+ // search rows to find the one that straddles character n
+ find->y = 0;
+
+ for(;;) {
+ STB_TEXTEDIT_LAYOUTROW(&r, str, i);
+ if (n < i + r.num_chars)
+ break;
+ prev_start = i;
+ i += r.num_chars;
+ find->y += r.baseline_y_delta;
+ }
+
+ find->first_char = first = i;
+ find->length = r.num_chars;
+ find->height = r.ymax - r.ymin;
+ find->prev_first = prev_start;
+
+ // now scan to find xpos
+ find->x = r.x0;
+ i = 0;
+ for (i=0; first+i < n; ++i)
+ find->x += STB_TEXTEDIT_GETWIDTH(str, first, i);
+}
+
+#define STB_TEXT_HAS_SELECTION(s) ((s)->select_start != (s)->select_end)
+
+// make the selection/cursor state valid if client altered the string
+static void stb_textedit_clamp(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+ int n = STB_TEXTEDIT_STRINGLEN(str);
+ if (STB_TEXT_HAS_SELECTION(state)) {
+ if (state->select_start > n) state->select_start = n;
+ if (state->select_end > n) state->select_end = n;
+ // if clamping forced them to be equal, move the cursor to match
+ if (state->select_start == state->select_end)
+ state->cursor = state->select_start;
+ }
+ if (state->cursor > n) state->cursor = n;
+}
+
+// delete characters while updating undo
+static void stb_textedit_delete(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int where, int len)
+{
+ stb_text_makeundo_delete(str, state, where, len);
+ STB_TEXTEDIT_DELETECHARS(str, where, len);
+ state->has_preferred_x = 0;
+}
+
+// delete the section
+static void stb_textedit_delete_selection(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+ stb_textedit_clamp(str, state);
+ if (STB_TEXT_HAS_SELECTION(state)) {
+ if (state->select_start < state->select_end) {
+ stb_textedit_delete(str, state, state->select_start, state->select_end - state->select_start);
+ state->select_end = state->cursor = state->select_start;
+ } else {
+ stb_textedit_delete(str, state, state->select_end, state->select_start - state->select_end);
+ state->select_start = state->cursor = state->select_end;
+ }
+ state->has_preferred_x = 0;
+ }
+}
+
+// canoncialize the selection so start <= end
+static void stb_textedit_sortselection(STB_TexteditState *state)
+{
+ if (state->select_end < state->select_start) {
+ int temp = state->select_end;
+ state->select_end = state->select_start;
+ state->select_start = temp;
+ }
+}
+
+// move cursor to first character of selection
+static void stb_textedit_move_to_first(STB_TexteditState *state)
+{
+ if (STB_TEXT_HAS_SELECTION(state)) {
+ stb_textedit_sortselection(state);
+ state->cursor = state->select_start;
+ state->select_end = state->select_start;
+ state->has_preferred_x = 0;
+ }
+}
+
+// move cursor to last character of selection
+static void stb_textedit_move_to_last(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+ if (STB_TEXT_HAS_SELECTION(state)) {
+ stb_textedit_sortselection(state);
+ stb_textedit_clamp(str, state);
+ state->cursor = state->select_end;
+ state->select_start = state->select_end;
+ state->has_preferred_x = 0;
+ }
+}
+
+#ifdef STB_TEXTEDIT_IS_SPACE
+static int is_word_boundary( STB_TEXTEDIT_STRING *str, int idx )
+{
+ return idx > 0 ? (STB_TEXTEDIT_IS_SPACE( STB_TEXTEDIT_GETCHAR(str,idx-1) ) && !STB_TEXTEDIT_IS_SPACE( STB_TEXTEDIT_GETCHAR(str, idx) ) ) : 1;
+}
+
+#ifndef STB_TEXTEDIT_MOVEWORDLEFT
+static int stb_textedit_move_to_word_previous( STB_TEXTEDIT_STRING *str, int c )
+{
+ --c; // always move at least one character
+ while( c >= 0 && !is_word_boundary( str, c ) )
+ --c;
+
+ if( c < 0 )
+ c = 0;
+
+ return c;
+}
+#define STB_TEXTEDIT_MOVEWORDLEFT stb_textedit_move_to_word_previous
+#endif
+
+#ifndef STB_TEXTEDIT_MOVEWORDRIGHT
+static int stb_textedit_move_to_word_next( STB_TEXTEDIT_STRING *str, int c )
+{
+ const int len = STB_TEXTEDIT_STRINGLEN(str);
+ ++c; // always move at least one character
+ while( c < len && !is_word_boundary( str, c ) )
+ ++c;
+
+ if( c > len )
+ c = len;
+
+ return c;
+}
+#define STB_TEXTEDIT_MOVEWORDRIGHT stb_textedit_move_to_word_next
+#endif
+
+#endif
+
+// update selection and cursor to match each other
+static void stb_textedit_prep_selection_at_cursor(STB_TexteditState *state)
+{
+ if (!STB_TEXT_HAS_SELECTION(state))
+ state->select_start = state->select_end = state->cursor;
+ else
+ state->cursor = state->select_end;
+}
+
+// API cut: delete selection
+static int stb_textedit_cut(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+ if (STB_TEXT_HAS_SELECTION(state)) {
+ stb_textedit_delete_selection(str,state); // implicity clamps
+ state->has_preferred_x = 0;
+ return 1;
+ }
+ return 0;
+}
+
+// API paste: replace existing selection with passed-in text
+static int stb_textedit_paste(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, STB_TEXTEDIT_CHARTYPE const *ctext, int len)
+{
+ STB_TEXTEDIT_CHARTYPE *text = (STB_TEXTEDIT_CHARTYPE *) ctext;
+ // if there's a selection, the paste should delete it
+ stb_textedit_clamp(str, state);
+ stb_textedit_delete_selection(str,state);
+ // try to insert the characters
+ if (STB_TEXTEDIT_INSERTCHARS(str, state->cursor, text, len)) {
+ stb_text_makeundo_insert(state, state->cursor, len);
+ state->cursor += len;
+ state->has_preferred_x = 0;
+ return 1;
+ }
+ // remove the undo since we didn't actually insert the characters
+ if (state->undostate.undo_point)
+ --state->undostate.undo_point;
+ return 0;
+}
+
+// API key: process a keyboard input
+static void stb_textedit_key(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int key)
+{
+retry:
+ switch (key) {
+ default: {
+ int c = STB_TEXTEDIT_KEYTOTEXT(key);
+ if (c > 0) {
+ STB_TEXTEDIT_CHARTYPE ch = (STB_TEXTEDIT_CHARTYPE) c;
+
+ // can't add newline in single-line mode
+ if (c == '\n' && state->single_line)
+ break;
+
+ if (state->insert_mode && !STB_TEXT_HAS_SELECTION(state) && state->cursor < STB_TEXTEDIT_STRINGLEN(str)) {
+ stb_text_makeundo_replace(str, state, state->cursor, 1, 1);
+ STB_TEXTEDIT_DELETECHARS(str, state->cursor, 1);
+ if (STB_TEXTEDIT_INSERTCHARS(str, state->cursor, &ch, 1)) {
+ ++state->cursor;
+ state->has_preferred_x = 0;
+ }
+ } else {
+ stb_textedit_delete_selection(str,state); // implicity clamps
+ if (STB_TEXTEDIT_INSERTCHARS(str, state->cursor, &ch, 1)) {
+ stb_text_makeundo_insert(state, state->cursor, 1);
+ ++state->cursor;
+ state->has_preferred_x = 0;
+ }
+ }
+ }
+ break;
+ }
+
+#ifdef STB_TEXTEDIT_K_INSERT
+ case STB_TEXTEDIT_K_INSERT:
+ state->insert_mode = !state->insert_mode;
+ break;
+#endif
+
+ case STB_TEXTEDIT_K_UNDO:
+ stb_text_undo(str, state);
+ state->has_preferred_x = 0;
+ break;
+
+ case STB_TEXTEDIT_K_REDO:
+ stb_text_redo(str, state);
+ state->has_preferred_x = 0;
+ break;
+
+ case STB_TEXTEDIT_K_LEFT:
+ // if currently there's a selection, move cursor to start of selection
+ if (STB_TEXT_HAS_SELECTION(state))
+ stb_textedit_move_to_first(state);
+ else
+ if (state->cursor > 0)
+ --state->cursor;
+ state->has_preferred_x = 0;
+ break;
+
+ case STB_TEXTEDIT_K_RIGHT:
+ // if currently there's a selection, move cursor to end of selection
+ if (STB_TEXT_HAS_SELECTION(state))
+ stb_textedit_move_to_last(str, state);
+ else
+ ++state->cursor;
+ stb_textedit_clamp(str, state);
+ state->has_preferred_x = 0;
+ break;
+
+ case STB_TEXTEDIT_K_LEFT | STB_TEXTEDIT_K_SHIFT:
+ stb_textedit_clamp(str, state);
+ stb_textedit_prep_selection_at_cursor(state);
+ // move selection left
+ if (state->select_end > 0)
+ --state->select_end;
+ state->cursor = state->select_end;
+ state->has_preferred_x = 0;
+ break;
+
+#ifdef STB_TEXTEDIT_MOVEWORDLEFT
+ case STB_TEXTEDIT_K_WORDLEFT:
+ if (STB_TEXT_HAS_SELECTION(state))
+ stb_textedit_move_to_first(state);
+ else {
+ state->cursor = STB_TEXTEDIT_MOVEWORDLEFT(str, state->cursor);
+ stb_textedit_clamp( str, state );
+ }
+ break;
+
+ case STB_TEXTEDIT_K_WORDLEFT | STB_TEXTEDIT_K_SHIFT:
+ if( !STB_TEXT_HAS_SELECTION( state ) )
+ stb_textedit_prep_selection_at_cursor(state);
+
+ state->cursor = STB_TEXTEDIT_MOVEWORDLEFT(str, state->cursor);
+ state->select_end = state->cursor;
+
+ stb_textedit_clamp( str, state );
+ break;
+#endif
+
+#ifdef STB_TEXTEDIT_MOVEWORDRIGHT
+ case STB_TEXTEDIT_K_WORDRIGHT:
+ if (STB_TEXT_HAS_SELECTION(state))
+ stb_textedit_move_to_last(str, state);
+ else {
+ state->cursor = STB_TEXTEDIT_MOVEWORDRIGHT(str, state->cursor);
+ stb_textedit_clamp( str, state );
+ }
+ break;
+
+ case STB_TEXTEDIT_K_WORDRIGHT | STB_TEXTEDIT_K_SHIFT:
+ if( !STB_TEXT_HAS_SELECTION( state ) )
+ stb_textedit_prep_selection_at_cursor(state);
+
+ state->cursor = STB_TEXTEDIT_MOVEWORDRIGHT(str, state->cursor);
+ state->select_end = state->cursor;
+
+ stb_textedit_clamp( str, state );
+ break;
+#endif
+
+ case STB_TEXTEDIT_K_RIGHT | STB_TEXTEDIT_K_SHIFT:
+ stb_textedit_prep_selection_at_cursor(state);
+ // move selection right
+ ++state->select_end;
+ stb_textedit_clamp(str, state);
+ state->cursor = state->select_end;
+ state->has_preferred_x = 0;
+ break;
+
+ case STB_TEXTEDIT_K_DOWN:
+ case STB_TEXTEDIT_K_DOWN | STB_TEXTEDIT_K_SHIFT: {
+ StbFindState find;
+ StbTexteditRow row;
+ int i, sel = (key & STB_TEXTEDIT_K_SHIFT) != 0;
+
+ if (state->single_line) {
+ // on windows, up&down in single-line behave like left&right
+ key = STB_TEXTEDIT_K_RIGHT | (key & STB_TEXTEDIT_K_SHIFT);
+ goto retry;
+ }
+
+ if (sel)
+ stb_textedit_prep_selection_at_cursor(state);
+ else if (STB_TEXT_HAS_SELECTION(state))
+ stb_textedit_move_to_last(str,state);
+
+ // compute current position of cursor point
+ stb_textedit_clamp(str, state);
+ stb_textedit_find_charpos(&find, str, state->cursor, state->single_line);
+
+ // now find character position down a row
+ if (find.length) {
+ float goal_x = state->has_preferred_x ? state->preferred_x : find.x;
+ float x;
+ int start = find.first_char + find.length;
+ state->cursor = start;
+ STB_TEXTEDIT_LAYOUTROW(&row, str, state->cursor);
+ x = row.x0;
+ for (i=0; i < row.num_chars; ++i) {
+ float dx = STB_TEXTEDIT_GETWIDTH(str, start, i);
+ #ifdef STB_TEXTEDIT_GETWIDTH_NEWLINE
+ if (dx == STB_TEXTEDIT_GETWIDTH_NEWLINE)
+ break;
+ #endif
+ x += dx;
+ if (x > goal_x)
+ break;
+ ++state->cursor;
+ }
+ stb_textedit_clamp(str, state);
+
+ state->has_preferred_x = 1;
+ state->preferred_x = goal_x;
+
+ if (sel)
+ state->select_end = state->cursor;
+ }
+ break;
+ }
+
+ case STB_TEXTEDIT_K_UP:
+ case STB_TEXTEDIT_K_UP | STB_TEXTEDIT_K_SHIFT: {
+ StbFindState find;
+ StbTexteditRow row;
+ int i, sel = (key & STB_TEXTEDIT_K_SHIFT) != 0;
+
+ if (state->single_line) {
+ // on windows, up&down become left&right
+ key = STB_TEXTEDIT_K_LEFT | (key & STB_TEXTEDIT_K_SHIFT);
+ goto retry;
+ }
+
+ if (sel)
+ stb_textedit_prep_selection_at_cursor(state);
+ else if (STB_TEXT_HAS_SELECTION(state))
+ stb_textedit_move_to_first(state);
+
+ // compute current position of cursor point
+ stb_textedit_clamp(str, state);
+ stb_textedit_find_charpos(&find, str, state->cursor, state->single_line);
+
+ // can only go up if there's a previous row
+ if (find.prev_first != find.first_char) {
+ // now find character position up a row
+ float goal_x = state->has_preferred_x ? state->preferred_x : find.x;
+ float x;
+ state->cursor = find.prev_first;
+ STB_TEXTEDIT_LAYOUTROW(&row, str, state->cursor);
+ x = row.x0;
+ for (i=0; i < row.num_chars; ++i) {
+ float dx = STB_TEXTEDIT_GETWIDTH(str, find.prev_first, i);
+ #ifdef STB_TEXTEDIT_GETWIDTH_NEWLINE
+ if (dx == STB_TEXTEDIT_GETWIDTH_NEWLINE)
+ break;
+ #endif
+ x += dx;
+ if (x > goal_x)
+ break;
+ ++state->cursor;
+ }
+ stb_textedit_clamp(str, state);
+
+ state->has_preferred_x = 1;
+ state->preferred_x = goal_x;
+
+ if (sel)
+ state->select_end = state->cursor;
+ }
+ break;
+ }
+
+ case STB_TEXTEDIT_K_DELETE:
+ case STB_TEXTEDIT_K_DELETE | STB_TEXTEDIT_K_SHIFT:
+ if (STB_TEXT_HAS_SELECTION(state))
+ stb_textedit_delete_selection(str, state);
+ else {
+ int n = STB_TEXTEDIT_STRINGLEN(str);
+ if (state->cursor < n)
+ stb_textedit_delete(str, state, state->cursor, 1);
+ }
+ state->has_preferred_x = 0;
+ break;
+
+ case STB_TEXTEDIT_K_BACKSPACE:
+ case STB_TEXTEDIT_K_BACKSPACE | STB_TEXTEDIT_K_SHIFT:
+ if (STB_TEXT_HAS_SELECTION(state))
+ stb_textedit_delete_selection(str, state);
+ else {
+ stb_textedit_clamp(str, state);
+ if (state->cursor > 0) {
+ stb_textedit_delete(str, state, state->cursor-1, 1);
+ --state->cursor;
+ }
+ }
+ state->has_preferred_x = 0;
+ break;
+
+#ifdef STB_TEXTEDIT_K_TEXTSTART2
+ case STB_TEXTEDIT_K_TEXTSTART2:
+#endif
+ case STB_TEXTEDIT_K_TEXTSTART:
+ state->cursor = state->select_start = state->select_end = 0;
+ state->has_preferred_x = 0;
+ break;
+
+#ifdef STB_TEXTEDIT_K_TEXTEND2
+ case STB_TEXTEDIT_K_TEXTEND2:
+#endif
+ case STB_TEXTEDIT_K_TEXTEND:
+ state->cursor = STB_TEXTEDIT_STRINGLEN(str);
+ state->select_start = state->select_end = 0;
+ state->has_preferred_x = 0;
+ break;
+
+#ifdef STB_TEXTEDIT_K_TEXTSTART2
+ case STB_TEXTEDIT_K_TEXTSTART2 | STB_TEXTEDIT_K_SHIFT:
+#endif
+ case STB_TEXTEDIT_K_TEXTSTART | STB_TEXTEDIT_K_SHIFT:
+ stb_textedit_prep_selection_at_cursor(state);
+ state->cursor = state->select_end = 0;
+ state->has_preferred_x = 0;
+ break;
+
+#ifdef STB_TEXTEDIT_K_TEXTEND2
+ case STB_TEXTEDIT_K_TEXTEND2 | STB_TEXTEDIT_K_SHIFT:
+#endif
+ case STB_TEXTEDIT_K_TEXTEND | STB_TEXTEDIT_K_SHIFT:
+ stb_textedit_prep_selection_at_cursor(state);
+ state->cursor = state->select_end = STB_TEXTEDIT_STRINGLEN(str);
+ state->has_preferred_x = 0;
+ break;
+
+
+#ifdef STB_TEXTEDIT_K_LINESTART2
+ case STB_TEXTEDIT_K_LINESTART2:
+#endif
+ case STB_TEXTEDIT_K_LINESTART:
+ stb_textedit_clamp(str, state);
+ stb_textedit_move_to_first(state);
+ if (state->single_line)
+ state->cursor = 0;
+ else while (state->cursor > 0 && STB_TEXTEDIT_GETCHAR(str, state->cursor-1) != STB_TEXTEDIT_NEWLINE)
+ --state->cursor;
+ state->has_preferred_x = 0;
+ break;
+
+#ifdef STB_TEXTEDIT_K_LINEEND2
+ case STB_TEXTEDIT_K_LINEEND2:
+#endif
+ case STB_TEXTEDIT_K_LINEEND: {
+ int n = STB_TEXTEDIT_STRINGLEN(str);
+ stb_textedit_clamp(str, state);
+ stb_textedit_move_to_first(state);
+ if (state->single_line)
+ state->cursor = n;
+ else while (state->cursor < n && STB_TEXTEDIT_GETCHAR(str, state->cursor) != STB_TEXTEDIT_NEWLINE)
+ ++state->cursor;
+ state->has_preferred_x = 0;
+ break;
+ }
+
+#ifdef STB_TEXTEDIT_K_LINESTART2
+ case STB_TEXTEDIT_K_LINESTART2 | STB_TEXTEDIT_K_SHIFT:
+#endif
+ case STB_TEXTEDIT_K_LINESTART | STB_TEXTEDIT_K_SHIFT:
+ stb_textedit_clamp(str, state);
+ stb_textedit_prep_selection_at_cursor(state);
+ if (state->single_line)
+ state->cursor = 0;
+ else while (state->cursor > 0 && STB_TEXTEDIT_GETCHAR(str, state->cursor-1) != STB_TEXTEDIT_NEWLINE)
+ --state->cursor;
+ state->select_end = state->cursor;
+ state->has_preferred_x = 0;
+ break;
+
+#ifdef STB_TEXTEDIT_K_LINEEND2
+ case STB_TEXTEDIT_K_LINEEND2 | STB_TEXTEDIT_K_SHIFT:
+#endif
+ case STB_TEXTEDIT_K_LINEEND | STB_TEXTEDIT_K_SHIFT: {
+ int n = STB_TEXTEDIT_STRINGLEN(str);
+ stb_textedit_clamp(str, state);
+ stb_textedit_prep_selection_at_cursor(state);
+ if (state->single_line)
+ state->cursor = n;
+ else while (state->cursor < n && STB_TEXTEDIT_GETCHAR(str, state->cursor) != STB_TEXTEDIT_NEWLINE)
+ ++state->cursor;
+ state->select_end = state->cursor;
+ state->has_preferred_x = 0;
+ break;
+ }
+
+// @TODO:
+// STB_TEXTEDIT_K_PGUP - move cursor up a page
+// STB_TEXTEDIT_K_PGDOWN - move cursor down a page
+ }
+}
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Undo processing
+//
+// @OPTIMIZE: the undo/redo buffer should be circular
+
+static void stb_textedit_flush_redo(StbUndoState *state)
+{
+ state->redo_point = STB_TEXTEDIT_UNDOSTATECOUNT;
+ state->redo_char_point = STB_TEXTEDIT_UNDOCHARCOUNT;
+}
+
+// discard the oldest entry in the undo list
+static void stb_textedit_discard_undo(StbUndoState *state)
+{
+ if (state->undo_point > 0) {
+ // if the 0th undo state has characters, clean those up
+ if (state->undo_rec[0].char_storage >= 0) {
+ int n = state->undo_rec[0].insert_length, i;
+ // delete n characters from all other records
+ state->undo_char_point = state->undo_char_point - (short) n; // vsnet05
+ STB_TEXTEDIT_memmove(state->undo_char, state->undo_char + n, (size_t) ((size_t)state->undo_char_point*sizeof(STB_TEXTEDIT_CHARTYPE)));
+ for (i=0; i < state->undo_point; ++i)
+ if (state->undo_rec[i].char_storage >= 0)
+ state->undo_rec[i].char_storage = state->undo_rec[i].char_storage - (short) n; // vsnet05 // @OPTIMIZE: get rid of char_storage and infer it
+ }
+ --state->undo_point;
+ STB_TEXTEDIT_memmove(state->undo_rec, state->undo_rec+1, (size_t) ((size_t)state->undo_point*sizeof(state->undo_rec[0])));
+ }
+}
+
+// discard the oldest entry in the redo list--it's bad if this
+// ever happens, but because undo & redo have to store the actual
+// characters in different cases, the redo character buffer can
+// fill up even though the undo buffer didn't
+static void stb_textedit_discard_redo(StbUndoState *state)
+{
+ int k = STB_TEXTEDIT_UNDOSTATECOUNT-1;
+
+ if (state->redo_point <= k) {
+ // if the k'th undo state has characters, clean those up
+ if (state->undo_rec[k].char_storage >= 0) {
+ int n = state->undo_rec[k].insert_length, i;
+ // delete n characters from all other records
+ state->redo_char_point = state->redo_char_point + (short) n; // vsnet05
+ STB_TEXTEDIT_memmove(state->undo_char + state->redo_char_point, state->undo_char + state->redo_char_point-n, (size_t) ((size_t)(STB_TEXTEDIT_UNDOCHARCOUNT - state->redo_char_point)*sizeof(STB_TEXTEDIT_CHARTYPE)));
+ for (i=state->redo_point; i < k; ++i)
+ if (state->undo_rec[i].char_storage >= 0)
+ state->undo_rec[i].char_storage = state->undo_rec[i].char_storage + (short) n; // vsnet05
+ }
+ STB_TEXTEDIT_memmove(state->undo_rec + state->redo_point, state->undo_rec + state->redo_point-1, (size_t) ((size_t)(STB_TEXTEDIT_UNDOSTATECOUNT - state->redo_point)*sizeof(state->undo_rec[0])));
+ ++state->redo_point;
+ }
+}
+
+static StbUndoRecord *stb_text_create_undo_record(StbUndoState *state, int numchars)
+{
+ // any time we create a new undo record, we discard redo
+ stb_textedit_flush_redo(state);
+
+ // if we have no free records, we have to make room, by sliding the
+ // existing records down
+ if (state->undo_point == STB_TEXTEDIT_UNDOSTATECOUNT)
+ stb_textedit_discard_undo(state);
+
+ // if the characters to store won't possibly fit in the buffer, we can't undo
+ if (numchars > STB_TEXTEDIT_UNDOCHARCOUNT) {
+ state->undo_point = 0;
+ state->undo_char_point = 0;
+ return NULL;
+ }
+
+ // if we don't have enough free characters in the buffer, we have to make room
+ while (state->undo_char_point + numchars > STB_TEXTEDIT_UNDOCHARCOUNT)
+ stb_textedit_discard_undo(state);
+
+ return &state->undo_rec[state->undo_point++];
+}
+
+static STB_TEXTEDIT_CHARTYPE *stb_text_createundo(StbUndoState *state, int pos, int insert_len, int delete_len)
+{
+ StbUndoRecord *r = stb_text_create_undo_record(state, insert_len);
+ if (r == NULL)
+ return NULL;
+
+ r->where = pos;
+ r->insert_length = (short) insert_len;
+ r->delete_length = (short) delete_len;
+
+ if (insert_len == 0) {
+ r->char_storage = -1;
+ return NULL;
+ } else {
+ r->char_storage = state->undo_char_point;
+ state->undo_char_point = state->undo_char_point + (short) insert_len;
+ return &state->undo_char[r->char_storage];
+ }
+}
+
+static void stb_text_undo(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+ StbUndoState *s = &state->undostate;
+ StbUndoRecord u, *r;
+ if (s->undo_point == 0)
+ return;
+
+ // we need to do two things: apply the undo record, and create a redo record
+ u = s->undo_rec[s->undo_point-1];
+ r = &s->undo_rec[s->redo_point-1];
+ r->char_storage = -1;
+
+ r->insert_length = u.delete_length;
+ r->delete_length = u.insert_length;
+ r->where = u.where;
+
+ if (u.delete_length) {
+ // if the undo record says to delete characters, then the redo record will
+ // need to re-insert the characters that get deleted, so we need to store
+ // them.
+
+ // there are three cases:
+ // there's enough room to store the characters
+ // characters stored for *redoing* don't leave room for redo
+ // characters stored for *undoing* don't leave room for redo
+ // if the last is true, we have to bail
+
+ if (s->undo_char_point + u.delete_length >= STB_TEXTEDIT_UNDOCHARCOUNT) {
+ // the undo records take up too much character space; there's no space to store the redo characters
+ r->insert_length = 0;
+ } else {
+ int i;
+
+ // there's definitely room to store the characters eventually
+ while (s->undo_char_point + u.delete_length > s->redo_char_point) {
+ // there's currently not enough room, so discard a redo record
+ stb_textedit_discard_redo(s);
+ // should never happen:
+ if (s->redo_point == STB_TEXTEDIT_UNDOSTATECOUNT)
+ return;
+ }
+ r = &s->undo_rec[s->redo_point-1];
+
+ r->char_storage = s->redo_char_point - u.delete_length;
+ s->redo_char_point = s->redo_char_point - (short) u.delete_length;
+
+ // now save the characters
+ for (i=0; i < u.delete_length; ++i)
+ s->undo_char[r->char_storage + i] = STB_TEXTEDIT_GETCHAR(str, u.where + i);
+ }
+
+ // now we can carry out the deletion
+ STB_TEXTEDIT_DELETECHARS(str, u.where, u.delete_length);
+ }
+
+ // check type of recorded action:
+ if (u.insert_length) {
+ // easy case: was a deletion, so we need to insert n characters
+ STB_TEXTEDIT_INSERTCHARS(str, u.where, &s->undo_char[u.char_storage], u.insert_length);
+ s->undo_char_point -= u.insert_length;
+ }
+
+ state->cursor = u.where + u.insert_length;
+
+ s->undo_point--;
+ s->redo_point--;
+}
+
+static void stb_text_redo(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+ StbUndoState *s = &state->undostate;
+ StbUndoRecord *u, r;
+ if (s->redo_point == STB_TEXTEDIT_UNDOSTATECOUNT)
+ return;
+
+ // we need to do two things: apply the redo record, and create an undo record
+ u = &s->undo_rec[s->undo_point];
+ r = s->undo_rec[s->redo_point];
+
+ // we KNOW there must be room for the undo record, because the redo record
+ // was derived from an undo record
+
+ u->delete_length = r.insert_length;
+ u->insert_length = r.delete_length;
+ u->where = r.where;
+ u->char_storage = -1;
+
+ if (r.delete_length) {
+ // the redo record requires us to delete characters, so the undo record
+ // needs to store the characters
+
+ if (s->undo_char_point + u->insert_length > s->redo_char_point) {
+ u->insert_length = 0;
+ u->delete_length = 0;
+ } else {
+ int i;
+ u->char_storage = s->undo_char_point;
+ s->undo_char_point = s->undo_char_point + u->insert_length;
+
+ // now save the characters
+ for (i=0; i < u->insert_length; ++i)
+ s->undo_char[u->char_storage + i] = STB_TEXTEDIT_GETCHAR(str, u->where + i);
+ }
+
+ STB_TEXTEDIT_DELETECHARS(str, r.where, r.delete_length);
+ }
+
+ if (r.insert_length) {
+ // easy case: need to insert n characters
+ STB_TEXTEDIT_INSERTCHARS(str, r.where, &s->undo_char[r.char_storage], r.insert_length);
+ s->redo_char_point += r.insert_length;
+ }
+
+ state->cursor = r.where + r.insert_length;
+
+ s->undo_point++;
+ s->redo_point++;
+}
+
+static void stb_text_makeundo_insert(STB_TexteditState *state, int where, int length)
+{
+ stb_text_createundo(&state->undostate, where, 0, length);
+}
+
+static void stb_text_makeundo_delete(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int where, int length)
+{
+ int i;
+ STB_TEXTEDIT_CHARTYPE *p = stb_text_createundo(&state->undostate, where, length, 0);
+ if (p) {
+ for (i=0; i < length; ++i)
+ p[i] = STB_TEXTEDIT_GETCHAR(str, where+i);
+ }
+}
+
+static void stb_text_makeundo_replace(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int where, int old_length, int new_length)
+{
+ int i;
+ STB_TEXTEDIT_CHARTYPE *p = stb_text_createundo(&state->undostate, where, old_length, new_length);
+ if (p) {
+ for (i=0; i < old_length; ++i)
+ p[i] = STB_TEXTEDIT_GETCHAR(str, where+i);
+ }
+}
+
+// reset the state to default
+static void stb_textedit_clear_state(STB_TexteditState *state, int is_single_line)
+{
+ state->undostate.undo_point = 0;
+ state->undostate.undo_char_point = 0;
+ state->undostate.redo_point = STB_TEXTEDIT_UNDOSTATECOUNT;
+ state->undostate.redo_char_point = STB_TEXTEDIT_UNDOCHARCOUNT;
+ state->select_end = state->select_start = 0;
+ state->cursor = 0;
+ state->has_preferred_x = 0;
+ state->preferred_x = 0;
+ state->cursor_at_end_of_line = 0;
+ state->initialized = 1;
+ state->single_line = (unsigned char) is_single_line;
+ state->insert_mode = 0;
+}
+
+// API initialize
+static void stb_textedit_initialize_state(STB_TexteditState *state, int is_single_line)
+{
+ stb_textedit_clear_state(state, is_single_line);
+}
+#endif//STB_TEXTEDIT_IMPLEMENTATION