-struct Corners {
- struct yx_uint16 tl;
- struct yx_uint16 tr;
- struct yx_uint16 bl;
- struct yx_uint16 br; };
-
-static void refit_pad (struct WinMeta *);
-static void place_win (struct WinMeta *, struct Win *);
-static void update_wins (struct WinMeta *, struct Win *);
-static void destroy_win (struct Win *);
-static void draw_wins_borders (struct Win *, struct Win *, struct Corners *, uint16_t);
-static void draw_win_borders (struct Win *, char);
-static void draw_wins (struct Win *);
-
-extern struct WinMeta init_win_meta (WINDOW * screen) {
-// Create and populate WinMeta struct with sane default values.
- struct WinMeta wmeta;
- wmeta.screen = screen;
- wmeta.pad.size.y = getmaxy(screen);
- wmeta.pad.size.x = getmaxx(screen);
- wmeta.chain_start = 0;
- wmeta.chain_end = 0;
- wmeta.pad_offset = 0;
- wmeta.pad.curses_win = newpad(wmeta.pad.size.y, 1);
- wmeta.active = 0;
- return wmeta; }
-
-extern struct Win init_win (struct WinMeta * wmeta, char * title, void * data, void * func) {
-// Create and populate Win struct with sane default values.
- struct Win w;
- w.prev = 0;
- w.next = 0;
- w.frame.curses_win = 0;
- w.title = title;
- w.frame.size.x = 20;
- w.frame.size.y = wmeta->pad.size.y - 1;
- w.data = data;
- w.draw = func;
- return w; }
-
-extern void append_win (struct WinMeta * wmeta, struct Win * w) {
-// Append win to window chain. Set active, if first window. Update geometry of windows from new window on.
- if (0 != wmeta->chain_start) {
- w->prev = wmeta->chain_end;
- wmeta->chain_end->next = w; }
- else {
- wmeta->active = w;
- wmeta->chain_start = w; }
- wmeta->chain_end = w;
- update_wins(wmeta, w); }
-
-static void refit_pad (struct WinMeta * wmeta) {
-// Fit pad width to minimum width demanded by current windows' geometries.
- uint16_t lastwincol = 0;
- struct Win * w_p = wmeta->chain_start;
- while (w_p != 0) {
- if (w_p->start.x + w_p->frame.size.x > lastwincol + 1)
- lastwincol = w_p->start.x + w_p->frame.size.x - 1;
- w_p = w_p->next; }
- if (getmaxx(wmeta->pad.curses_win) != lastwincol)
- wresize(wmeta->pad.curses_win, getmaxy(wmeta->pad.curses_win), lastwincol + 2); }
-
-extern void suspend_win (struct WinMeta * wmeta, struct Win * w) {
-// Destroy win, suspend from chain. Update geometry of following rows and pad, as well as activity selection.
- destroy_win(w);
- if (wmeta->chain_start != w) // Give win's position in the chain to element next to it in the chain.
- w->prev->next = w->next;
- else
- wmeta->chain_start = w->next;
- char pad_refitted = 0;
- if (wmeta->chain_end != w) { // Let chain element next to win know its new predecessor.
- w->next->prev = w->prev;
- if (wmeta->active == w) // If win was active, shift active window pointer to
- wmeta->active = w->next; // the next chain element, if that is a window ...
- update_wins(wmeta, w->next);
- pad_refitted = 1; }
- else {
- wmeta->chain_end = w->prev;
- if (wmeta->active == w) // ... or else to the previous element.
- wmeta->active = w->prev; }
- w->prev = 0;
- w->next = 0;
- if (0 == pad_refitted) // Refit pad if necessary.
- refit_pad(wmeta); }
-
-static void place_win (struct WinMeta * wmeta, struct Win * w) {
-// Based on position and sizes of previous window, find fitting place for current window.
- w->start.x = 0; // if window is first in chain, place it on top-left corner
- w->start.y = 1;
- if (0 != w->prev) {
- struct Win * w_top = w->prev;
- while (w_top->start.y != 1)
- w_top = w_top->prev; // else, default to placing window in new top
- w->start.x = w_top->start.x + w_top->frame.size.x + 1; // column to the right of the last one
- uint16_t w_prev_maxy = w->prev->start.y + getmaxy(w->prev->frame.curses_win);
- if (w->frame.size.x <= w->prev->frame.size.x && w->frame.size.y < wmeta->pad.size.y - w_prev_maxy) {
- w->start.x = w->prev->start.x; // place window below previous window if it fits
- w->start.y = w_prev_maxy + 1; } // vertically and is not wider than its predecessor
- else {
- struct Win * w_up = w->prev;
- struct Win * w_upup = w_up;
- uint16_t widthdiff;
- while (w_up != w_top) {
- w_upup = w_up->prev;
- while (1) {
- if (w_up->start.y != w_upup->start.y)
- break;
- w_upup = w_upup->prev; }
- w_prev_maxy = w_upup->start.y + getmaxy(w_upup->frame.curses_win);
- widthdiff = (w_upup->start.x + w_upup->frame.size.x) - (w_up->start.x + w_up->frame.size.x);
- if (w->frame.size.y < wmeta->pad.size.y - w_prev_maxy && w->frame.size.x < widthdiff) {
- w->start.x = w_up->start.x + w_up->frame.size.x + 1 ; // else try to open new sub column under
- w->start.y = w_prev_maxy + 1; // last window below which enough space remains
- break; }
- w_up = w_upup; } } } }
-
-static void update_wins (struct WinMeta * wmeta, struct Win * w) {
-// Update geometry of win and its next of kin. Destroy (if visible), (re-)build window. If need, resize pad.
- if (0 != w->frame.curses_win)
- destroy_win (w);
- place_win(wmeta, w);
- refit_pad(wmeta);
- w->frame.curses_win=subpad(wmeta->pad.curses_win, w->frame.size.y, w->frame.size.x, w->start.y, w->start.x);
- if (0 != w->next)
- update_wins (wmeta, w->next); }
-
-static void destroy_win (struct Win * w) {
-// Delete window.
- delwin(w->frame.curses_win);
- w->frame.curses_win = 0; }
-
-static void draw_win_borders (struct Win * w, char active) {
-// Draw borders of window win, including title. Decorate in a special way if window is marked as active.
- uint16_t y, x;
- for (y = w->start.y; y <= w->start.y + w->frame.size.y; y++) {
- mvwaddch(wgetparent(w->frame.curses_win), y, w->start.x - 1, '|');
- mvwaddch(wgetparent(w->frame.curses_win), y, w->start.x + w->frame.size.x, '|'); }
- for (x = w->start.x; x <= w->start.x + w->frame.size.x; x++) {
- mvwaddch(wgetparent(w->frame.curses_win), w->start.y - 1, x, '-');
- mvwaddch(wgetparent(w->frame.curses_win), w->start.y + w->frame.size.y, x, '-'); }
- char min_title_length_visible = 3; // 1 char minimal, plus 2 chars for decoration left/right of title
- if (w->frame.size.x >= min_title_length_visible) {
- uint16_t title_offset = 0;
- if (w->frame.size.x > strlen(w->title) + 2)
- title_offset = (w->frame.size.x - (strlen(w->title) + 2)) / 2; // + 2 is for decoration
- uint16_t length_visible = strnlen(w->title, w->frame.size.x - 2);
- char title[length_visible + 3];
- char decoration = ' ';
- if (1 == active)
- decoration = '$';
- memcpy(title + 1, w->title, length_visible);
- title[0] = title[length_visible + 1] = decoration;
- title[length_visible + 2] = '\0';
- mvwaddstr(wgetparent(w->frame.curses_win), w->start.y - 1, w->start.x + title_offset, title); } }
-
-static void draw_wins_borders (struct Win * w, struct Win * w_active, struct Corners * corners, uint16_t i) {
-// Call draw_win_borders() for all windows in chain from win on. Save current window's border corners.
- char active = 0;
- if (w == w_active)
- active = 1;
- draw_win_borders(w, active);
- corners[i].tl.y = w->start.y - 1;
- corners[i].tl.x = w->start.x - 1;
- corners[i].tr.y = w->start.y - 1;
- corners[i].tr.x = w->start.x + w->frame.size.x;
- corners[i].bl.y = w->start.y + w->frame.size.y;
- corners[i].bl.x = w->start.x - 1;
- corners[i].br.y = w->start.y + w->frame.size.y;
- corners[i].br.x = w->start.x + w->frame.size.x;
- if (0 != w->next) {
- draw_wins_borders (w->next, w_active, corners, i + 1); } }
-
-static void draw_wins (struct Win * w) {
-// Draw contents of all windows in window chain from win on.
- w->draw(w);
- if (0 != w->next) {
- draw_wins (w->next); } }
-
-extern void draw_scroll_hint (struct Frame * frame, uint16_t pos, uint32_t dist, char dir) {
-// Draw scroll hint into frame at pos (row or col dependend on dir), mark distance of dist cells into dir.
- char more[] = "more";
- char unit_cols[] = "columns";
- char unit_rows[] = "lines";
- uint16_t dsc_space = frame->size.x;
- char * unit = unit_rows;
- if ('<' == dir || '>' == dir) {
- dsc_space = frame->size.y;
- unit = unit_cols; }
- char * scrolldsc = malloc((4 * sizeof(char)) + strlen(more) + strlen(unit) + 10); // 10 = uint32 max strlen
- sprintf(scrolldsc, " %d %s %s ", dist, more, unit);
- char offset = 1, q;
- if (dsc_space > strlen(scrolldsc) + 1)
- offset = (dsc_space - strlen(scrolldsc)) / 2;
- chtype symbol;
- for (q = 0; q < dsc_space; q++) {
- if (q >= offset && q < strlen(scrolldsc) + offset)
- symbol = scrolldsc[q - offset] | A_REVERSE;
- else
- symbol = dir | A_REVERSE;
+
+
+/* Make virtual screen just wide enough to contain all visible windows. */
+static void refit_pad();
+
+/* Update geometry (sizes, positions) of window "w" and its successors in the
+ * window chain. Use place_win() for the positioning algorithm.
+ */
+static void update_wins(struct Win * w);
+static void place_win(struct Win * w);
+
+/* Draw scroll hint (a line saying that there are "dist" more elements of "unit"
+ * further into the direction symbolized by "dir") into virtual screen, onto an
+ * appropriate edge of a window or the screen; the left/right edge if "dir" is
+ * "<"/">", or the top/bottom edge if it is "^"/"v". "start" be either the start
+ * coordinate of a window's frame, or .y=0, .x=wm->pad_offset for the virtual
+ * screen. winscroll_hint() and padscroll_hint() are wrappers to both cases.
+ */
+static void scroll_hint(struct yx_uint16 fsize, char dir, uint16_t dist,
+ char * unit, struct yx_uint16 start);
+static void winscroll_hint(struct Win * w, char dir, uint16_t dist);
+static void padscroll_hint(char dir, uint16_t dist);
+
+/* Draw contents of all windows in window chain from window "w" onwards. */
+static void draw_wins(struct Win * w);
+
+/* draw_win_borderlines() draws vertical/horizontal borders of window "w" sans
+ * corners into the virtual screen. It draws the top border line as the windows'
+ * title bar (highlighted if the window is selected as active). It is called
+ * recursively by draw_wins_borderlines() on all windows from "w" on.
+ * draw_wins_bordercorners() draws the border corners of "w" and its successors.
+ */
+static void draw_win_borderlines(struct Win * w);
+static void draw_wins_borderlines(struct Win * w);
+static void draw_wins_bordercorners(struct Win * w);
+
+/* Shift active window forwards / backwards in window chain. */
+static void shift_win_forward();
+static void shift_win_backward();
+
+
+
+static void refit_pad()
+{
+ /* Determine rightmost window column. */
+ uint32_t lastwcol = 0;
+ struct Win * wp = world.wmeta->chain_start;
+ while (wp != 0)
+ {
+ if ((uint32_t) wp->start.x + (uint32_t) wp->framesize.x > lastwcol + 1)
+ {
+ lastwcol = (uint32_t) wp->start.x + (uint32_t) wp->framesize.x - 1;
+ }
+ wp = wp->next;
+ }
+
+ /* Only resize the pad if the rightmost window column has changed. */
+ char * err_s = "refit_pad() extends virtual screen beyond legal sizes.";
+ char * err_m = "refit_pad() triggers memory alloc error via wresize().";
+ if (getmaxx(world.wmeta->pad) + 1 != lastwcol)
+ {
+ uint8_t t = (lastwcol + 2 > UINT16_MAX);
+ exit_err(t, err_s);
+ t = wresize(world.wmeta->pad, getmaxy(world.wmeta->pad), lastwcol + 2);
+ exit_err(t, err_m);
+ }
+}
+
+
+
+static void update_wins(struct Win * w)
+{
+ place_win(w);
+ refit_pad();
+ if (0 != w->next)
+ {
+ update_wins(w->next);
+ }
+}
+
+
+
+static void place_win(struct Win * w)
+{
+ /* If w is first window, it goes into the top left corner. */
+ w->start.x = 0;
+ w->start.y = 1; /* Leave space for title bar. */
+ if (0 != w->prev)
+ {
+
+ /* If not, fit w's top left to top right of last top predecessor. */
+ struct Win * w_top = w->prev;
+ while (w_top->start.y != 1)
+ {
+ w_top = w_top->prev;
+ }
+ w->start.x = w_top->start.x + w_top->framesize.x + 1;
+
+ /* Fit w's top left to bottom left of its ->prev if enough space. */
+ uint16_t w_prev_maxy = w->prev->start.y + w->prev->framesize.y;
+ if ( w->framesize.x <= w->prev->framesize.x
+ && w->framesize.y < world.wmeta->padsize.y - w_prev_maxy)
+ {
+ w->start.x = w->prev->start.x;
+ w->start.y = w_prev_maxy + 1;
+ }
+
+ /* Failing that, try to fit w' top left to the top right of the last
+ * predecessor w_test 1) not followed by windows with a left corner
+ * further rightwards than its own 2) with enough space rightwards for w
+ * until the bottom right of w_thr directly throning over it 3) and with
+ * this same space extending far enough to the bottom for fitting in w.
+ */
+ else
+ {
+ struct Win * w_test = w->prev;
+ struct Win * w_thr;
+ while (w_test != w_top)
+ {
+ w_thr = w_test->prev;
+ for (; w_test->start.y <= w_thr->start.y; w_thr = w_thr->prev);
+ uint16_t w_thr_bottom = w_thr->start.y + w_thr->framesize.y;
+ uint16_t free_width = (w_thr->start.x + w_thr->framesize.x)
+ - (w_test->start.x + w_test->framesize.x);
+ if ( w->framesize.y < world.wmeta->padsize.y - w_thr_bottom
+ && w->framesize.x < free_width)
+ {
+ w->start.x = w_test->start.x + w_test->framesize.x + 1;
+ w->start.y = w_thr_bottom + 1;
+ break;
+ }
+ w_test = w_thr;
+ }
+ }
+ }
+}
+
+
+
+static void scroll_hint(struct yx_uint16 fsize, char dir, uint16_t dist,
+ char * unit, struct yx_uint16 start)
+{
+ /* Decide on alignment (vertical/horizontal?), thereby hint text space. */
+ char * more = "more";
+ uint16_t dsc_space = fsize.x;
+ if ('<' == dir || '>' == dir)
+ {
+ dsc_space = fsize.y;
+ } /* vv-- 10 = max strlen for uint16_t */
+ char scrolldsc[1 + strlen(more) + 1 + 10 + 1 + strlen(unit) + 1 + 1];
+ sprintf(scrolldsc, " %d %s %s ", dist, more, unit);
+
+ /* Decide on offset of the description text inside the scroll hint line. */
+ uint16_t dsc_offset = 1;
+ if (dsc_space > strlen(scrolldsc) + 1)
+ {
+ dsc_offset = (dsc_space - strlen(scrolldsc)) / 2;
+ }
+
+ /* Draw scroll hint line as dir symbols bracketing description text. */
+ uint16_t draw_offset = 0;
+ if ('>' == dir)
+ {
+ draw_offset = fsize.x - 1;
+ }
+ else if ('v' == dir)
+ {
+ draw_offset = fsize.y - 1;
+ }
+ uint16_t q = 0;
+ for (; q < dsc_space; q++)
+ {
+ chtype c = dir | A_REVERSE;
+ if (q >= dsc_offset && q < strlen(scrolldsc) + dsc_offset)
+ {
+ c = scrolldsc[q - dsc_offset] | A_REVERSE;
+ }
+ if ('<' == dir || '>' == dir)
+ {
+ mvwaddch(world.wmeta->pad, start.y + q, start.x + draw_offset, c);
+ continue;
+ }
+ mvwaddch(world.wmeta->pad, start.y + draw_offset, start.x + q, c);
+ }
+}
+
+
+static void padscroll_hint(char dir, uint16_t dist)
+{
+ struct yx_uint16 start;
+ start.y = 0;
+ start.x = world.wmeta->pad_offset;
+ scroll_hint(world.wmeta->padsize, dir, dist, "columns", start);
+}
+
+
+
+static void winscroll_hint(struct Win * w, char dir, uint16_t dist)
+{
+ char * unit = "lines";