+/* src/client/windows.c */
+
+#include "windows.h"
+#include <stdint.h> /* uint8_t, uint16_t, uint32_t, UINT16_MAX */
+#include <stdio.h> /* sprintf() */
+#include <stdlib.h> /* free() */
+#include <string.h> /* strlen(), memcpy(), strnlen() */
+#include <ncurses.h> /* pnoutrefresh(), doupdate(), werase(), wnoutrefresh(),
+ * erase(), getmaxx(), getmaxy(), delwin(), endwin(),
+ * initscr(), noecho(), curs_set(), newpad(), mvwaddch(),
+ * mvwaddstr(), wresize(), chtype
+ */
+#include "../common/rexit.h" /* for exit_err() */
+#include "../common/try_malloc.h" /* for try_malloc() */
+#include "../common/yx_uint16.h" /* for struct yx_uint16 */
+#include "cleanup.h" /* for set_cleanup_flag() */
+#include "misc.h" /* for center_offset() */
+#include "world.h" /* for world global */
+
+
+
+
+/* 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";
+ if ('<' == dir || '>' == dir)
+ {
+ unit = "columns";
+ }
+ struct yx_uint16 start = w->start;
+ scroll_hint(w->framesize, dir, dist, unit, start);
+}
+
+
+
+static void draw_wins(struct Win * w)
+{
+ w->draw(w);
+ uint16_t size_y = w->winmapsize.y;
+ uint16_t size_x = w->winmapsize.x;
+ uint16_t offset_y = center_offset(w->center.y, size_y, w->framesize.y);
+ uint16_t offset_x = center_offset(w->center.x, size_x, w->framesize.x);
+ uint16_t y, x;
+ for (y = offset_y; y < w->framesize.y + offset_y && y < size_y; y++)
+ {
+ for (x = offset_x; x < w->framesize.x + offset_x && x < size_x; x++)
+ {
+ chtype ch = w->winmap[(y * w->winmapsize.x) + x];
+ mvwaddch(world.wmeta.pad, w->start.y + (y - offset_y),
+ w->start.x + (x - offset_x), ch);
+ }
+ }
+ free(w->winmap);
+ w->winmap = NULL;
+ w->winmapsize.y = 0;
+ w->winmapsize.x = 0;
+ if (offset_y > 0)
+ {
+ winscroll_hint(w, '^', offset_y + 1);
+ }
+ if (size_y > offset_y + w->framesize.y)
+ {
+ winscroll_hint(w, 'v', size_y - ((offset_y + w->framesize.y) - 1));
+ }
+ if (offset_x > 0)
+ {
+ winscroll_hint(w, '<', offset_x + 1);
+ }
+ if (size_x > offset_x + w->framesize.x)
+ {
+ winscroll_hint(w, '>', size_x - ((offset_x + w->framesize.x) - 1));
+ }
+ if (0 != w->next)
+ {
+ return draw_wins(w->next);
+ }
+}
+
+
+
+static void draw_win_borderlines(struct Win * w)
+{
+ /* Draw vertical and horizontal border lines. */
+ uint16_t y, x;
+ for (y = w->start.y; y <= w->start.y + w->framesize.y; y++)
+ {
+ mvwaddch(world.wmeta.pad, y, w->start.x - 1, '|');
+ mvwaddch(world.wmeta.pad, y, w->start.x + w->framesize.x, '|');
+ }
+ for (x = w->start.x; x <= w->start.x + w->framesize.x; x++)
+ {
+ mvwaddch(world.wmeta.pad, w->start.y - 1, x, '-');
+ mvwaddch(world.wmeta.pad, w->start.y + w->framesize.y, x, '-');
+ }
+
+ /* Draw as much as possible of the title into center of top border line. */
+ char min_title_length_visible = 3; /* min. 1 char + 2 padding/decoration */
+ if (w->framesize.x >= min_title_length_visible)
+ {
+ uint16_t title_offset = 0;
+ if (w->framesize.x > strlen(w->title) + 2)
+ {
+ title_offset = (w->framesize.x - (strlen(w->title) + 2)) / 2;
+ } /* +2 is for padding/decoration */
+ uint16_t length_visible = strnlen(w->title, w->framesize.x - 2);
+ char title[length_visible + 3];
+ char decoration = ' ';
+ if (w == world.wmeta.active)
+ {
+ decoration = '$';
+ }
+ memcpy(title + 1, w->title, length_visible);
+ title[0] = title[length_visible + 1] = decoration;
+ title[length_visible + 2] = '\0';
+ mvwaddstr(world.wmeta.pad,
+ w->start.y - 1, w->start.x + title_offset, title);
+ }
+}
+
+
+
+static void draw_wins_borderlines(struct Win * w)
+{
+ draw_win_borderlines(w);
+ if (0 != w->next)
+ {
+ draw_wins_borderlines(w->next);
+ }
+}
+
+
+
+static void draw_wins_bordercorners(struct Win * w)
+{
+ mvwaddch(world.wmeta.pad, w->start.y - 1, w->start.x - 1, '+');
+ mvwaddch(world.wmeta.pad, w->start.y - 1, w->start.x + w->framesize.x,'+');
+ mvwaddch(world.wmeta.pad, w->start.y + w->framesize.y, w->start.x - 1,'+');
+ mvwaddch(world.wmeta.pad, w->start.y + w->framesize.y,
+ w->start.x + w->framesize.x, '+');
+ if (0 != w->next)
+ {
+ draw_wins_bordercorners(w->next);
+ }
+}
+
+
+
+static void shift_win_forward()
+{
+ if (world.wmeta.active == world.wmeta.chain_end)
+ {
+ world.wmeta.chain_end = world.wmeta.active->prev;
+ world.wmeta.chain_end->next = 0;
+ world.wmeta.active->next = world.wmeta.chain_start;
+ world.wmeta.active->next->prev = world.wmeta.active;
+ world.wmeta.chain_start = world.wmeta.active;
+ world.wmeta.chain_start->prev = 0;
+ }
+ else
+ {
+ struct Win * old_prev = world.wmeta.active->prev;
+ struct Win * old_next = world.wmeta.active->next;
+ if (world.wmeta.chain_end == world.wmeta.active->next)
+ {
+ world.wmeta.chain_end = world.wmeta.active;
+ world.wmeta.active->next = 0;
+ }
+ else
+ {
+ world.wmeta.active->next = old_next->next;
+ world.wmeta.active->next->prev = world.wmeta.active;
+ }
+ if (world.wmeta.chain_start == world.wmeta.active)
+ {
+ world.wmeta.chain_start = old_next;
+ }
+ else
+ {
+ old_prev->next = old_next;
+ }
+ old_next->prev = old_prev;
+ old_next->next = world.wmeta.active;
+ world.wmeta.active->prev = old_next;
+ }
+}
+
+
+
+static void shift_win_backward()
+{
+ if (world.wmeta.active == world.wmeta.chain_start)
+ {
+ world.wmeta.chain_start = world.wmeta.active->next;
+ world.wmeta.chain_start->prev = 0;
+ world.wmeta.active->prev = world.wmeta.chain_end;
+ world.wmeta.active->prev->next = world.wmeta.active;
+ world.wmeta.chain_end = world.wmeta.active;
+ world.wmeta.chain_end->next = 0;
+ }
+ else
+ {
+ struct Win * old_prev = world.wmeta.active->prev;
+ struct Win * old_next = world.wmeta.active->next;
+ if (world.wmeta.chain_start == world.wmeta.active->prev)
+ {
+ world.wmeta.chain_start = world.wmeta.active;
+ world.wmeta.active->prev = 0;
+ }
+ else
+ {
+ world.wmeta.active->prev = old_prev->prev;
+ world.wmeta.active->prev->next = world.wmeta.active;
+ }
+ if (world.wmeta.chain_end == world.wmeta.active)
+ {
+ world.wmeta.chain_end = old_prev;
+ }
+ else
+ {
+ old_next->prev = old_prev;
+ }
+ old_prev->next = old_next;
+ old_prev->prev = world.wmeta.active;
+ world.wmeta.active->next = old_prev;
+ }
+}
+
+
+
+extern void init_win_meta()
+{
+ char * err_s = "init_win_meta() creates virtual screen beyond legal size.";
+ char * err_m = "init_win_meta() triggers memory alloc error via newpad().";
+ world.wmeta.screen = initscr();
+ set_cleanup_flag(CLEANUP_NCURSES);
+ noecho();
+ curs_set(0);
+ uint32_t maxy_test = getmaxy(world.wmeta.screen);
+ uint32_t maxx_test = getmaxx(world.wmeta.screen);
+ exit_err(maxy_test > UINT16_MAX || maxx_test > UINT16_MAX, err_s);
+ world.wmeta.padsize.y = maxy_test;
+ world.wmeta.padsize.x = maxx_test;
+ world.wmeta.chain_start = 0;
+ world.wmeta.chain_end = 0;
+ world.wmeta.pad_offset = 0;
+ world.wmeta.pad = newpad(world.wmeta.padsize.y, 1);
+ exit_err(NULL == world.wmeta.pad, err_m);
+ world.wmeta.active = 0;
+}
+
+
+
+extern void init_win(struct Win ** wp, char * title, int16_t height,
+ int16_t width, void * func)
+{
+ char * f_name = "init_win()";
+ struct Win * w = try_malloc(sizeof(struct Win), f_name);
+ w->prev = 0;
+ w->next = 0;
+ w->winmapsize.y = 0;
+ w->winmapsize.x = 0;
+ w->winmap = NULL;
+ w->title = try_malloc(strlen(title) + 1, f_name);
+ sprintf(w->title, "%s", title);
+ w->draw = func;
+ w->center.y = 0;
+ w->center.x = 0;
+ if (0 < width)
+ {
+ w->framesize.x = width;
+ }
+ else if (0 >= width)
+ {
+ w->framesize.x = world.wmeta.padsize.x + width;
+ }
+ if (0 < height && height <= world.wmeta.padsize.y - 1)
+ {
+ w->framesize.y = height;
+ }
+ else if (0 >= height && world.wmeta.padsize.y + (height - 1) > 0)
+ {
+ w->framesize.y = world.wmeta.padsize.y + (height - 1);
+ }
+ *wp = w;
+}
+
+
+
+extern void free_winmeta_and_endwin()
+{
+ delwin(world.wmeta.pad);
+ endwin();
+}
+
+
+
+extern void free_win(struct Win * win)
+{
+ free(win->title);
+ free(win);
+}
+
+
+
+extern void append_win(struct Win * w)
+{
+ if (0 != world.wmeta.chain_start)
+ {
+ w->prev = world.wmeta.chain_end;
+ world.wmeta.chain_end->next = w;
+ }
+ else
+ {
+ world.wmeta.active = w;
+ world.wmeta.chain_start = w;
+ }
+ world.wmeta.chain_end = w;
+ update_wins(w);
+}
+
+
+
+extern void suspend_win(struct Win * w)
+{
+ if (world.wmeta.chain_start != w)
+ {
+ w->prev->next = w->next;
+ }
+ else
+ {
+ world.wmeta.chain_start = w->next;
+ }
+ uint8_t pad_refitted = 0;
+ if (world.wmeta.chain_end != w)
+ {
+ w->next->prev = w->prev;
+ if (world.wmeta.active == w)
+ {
+ world.wmeta.active = w->next;
+ }
+ update_wins(w->next); /* Positioning of successor windows may be */
+ pad_refitted = 1; /* affected / need correction. Note that */
+ } /* update_wins() already refits the pad, */
+ else /* voiding later need for that. */
+ {
+ world.wmeta.chain_end = w->prev;
+ if (world.wmeta.active == w)
+ {
+ world.wmeta.active = w->prev;
+ }
+ }
+ w->prev = 0;
+ w->next = 0;
+ if (0 == pad_refitted)
+ {
+ refit_pad();
+ }
+}
+
+
+
+extern void reset_pad_offset(uint16_t new_offset)
+{
+ if (new_offset >= 0
+ && (new_offset < world.wmeta.pad_offset
+ || new_offset + world.wmeta.padsize.x < getmaxx(world.wmeta.pad)))
+ {
+ world.wmeta.pad_offset = new_offset;
+ }
+}
+
+
+
+extern void resize_active_win(struct yx_uint16 size)
+{
+ if (0 != world.wmeta.active
+ && size.x > 0 && size.y > 0 && size.y < world.wmeta.padsize.y)
+ {
+ world.wmeta.active->framesize = size;
+ update_wins(world.wmeta.active); /* Positioning of following */
+ } /* windows may be affected. */
+}
+
+
+
+extern void cycle_active_win(char dir)
+{
+ if (0 != world.wmeta.active)
+ {
+ if ('f' == dir)
+ {
+ if (world.wmeta.active->next != 0)
+ {
+ world.wmeta.active = world.wmeta.active->next;
+ }
+ else
+ {
+ world.wmeta.active = world.wmeta.chain_start;
+ }
+ }
+ else
+ {
+ if (world.wmeta.active->prev != 0)
+ {
+ world.wmeta.active = world.wmeta.active->prev;
+ }
+ else
+ {
+ world.wmeta.active = world.wmeta.chain_end;
+ }
+ }
+ }
+}
+
+
+
+extern void shift_active_win(char dir)
+{
+ if ( 0 == world.wmeta.active /* No shifting with < 2 windows visible. */
+ || world.wmeta.chain_start == world.wmeta.chain_end)
+ {
+ return;
+ }
+ if ('f' == dir)
+ {
+ shift_win_forward();
+ update_wins(world.wmeta.chain_start);
+ return;
+ }
+ shift_win_backward();
+ update_wins(world.wmeta.chain_start);
+}
+
+
+
+extern void draw_all_wins()
+{
+ /* Empty everything before filling it a-new. */
+ erase();
+ wnoutrefresh(world.wmeta.screen);
+ werase(world.wmeta.pad);
+ if (world.wmeta.chain_start)
+ {
+
+ /* Draw windows' borders first, then windows. */
+ draw_wins_borderlines(world.wmeta.chain_start);
+ draw_wins_bordercorners(world.wmeta.chain_start);
+ draw_wins(world.wmeta.chain_start);
+
+ /* Draw virtual screen scroll hints. */
+ if (world.wmeta.pad_offset > 0)
+ {
+ padscroll_hint('<', world.wmeta.pad_offset + 1);
+ }
+ uint16_t size_x = getmaxx(world.wmeta.pad);
+ uint16_t right_edge = world.wmeta.pad_offset + world.wmeta.padsize.x;
+ if (right_edge < size_x - 1)
+ {
+ padscroll_hint('>', size_x - right_edge);
+ }
+
+ /* Write pad segment to be shown on physical screen to screen buffer. */
+ pnoutrefresh(world.wmeta.pad, 0, world.wmeta.pad_offset, 0, 0,
+ world.wmeta.padsize.y, world.wmeta.padsize.x - 1);
+ }
+
+ /* Only at the end write accumulated changes to the physical screen. */
+ doupdate();
+}