lib-viewer.c

   1 /*
   2  * Copyright Neil Brown ©2017-2023 <neil@brown.name>
   3  * May be distributed under terms of GPLv2 - see file:COPYING
   4  *
   5  * A viewer pane presents a read-only view on a document
   6  * which uses some letter - that would normally self-insert -
   7  * to move around.
   8  * Particularly:
   9  *  SPACE : page down
  10  *  BACKSPACE: page up
  11  *  q     : bury-document
  12  */
  13
  14 #include <unistd.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include <stdio.h>
  18 #define PANE_DATA_TYPE struct viewer_data
  19 #include "core.h"
  20
  21 struct viewer_data {
  22         bool active;
  23 };
  24 #include "core-pane.h"
  25
  26 static struct map *viewer_map safe;
  27 DEF_LOOKUP_CMD(viewer_handle, viewer_map);
  28
  29 static struct pane *safe do_viewer_attach(struct pane *par safe)
  30 {
  31         struct pane *p;
  32
  33         p = pane_register(par, 0, &viewer_handle.c);
  34         if (p)
  35                 p->data->active = True;
  36         return p;
  37 }
  38
  39 DEF_CMD(viewer_attach)
  40 {
  41         return comm_call(ci->comm2, "callback:attach", do_viewer_attach(ci->focus));
  42 }
  43
  44 DEF_CMD(no_replace)
  45 {
  46         struct viewer_data *vd = ci->home->data;
  47
  48         if (!vd->active)
  49                 return Efallthrough;
  50         call("Message:modal", ci->focus, 0, NULL, "Cannot modify document in viewer mode");
  51         return 1;
  52 }
  53
  54 DEF_CMD(viewer_cmd)
  55 {
  56         /* Send command to the document */
  57         char cmd[40];
  58         const char *s;
  59         struct viewer_data *vd = ci->home->data;
  60
  61         if (!vd->active)
  62                 return Efallthrough;
  63
  64         if ((s=ksuffix(ci, "K:"))[0] ||
  65             (s=ksuffix(ci, "doc:char-"))[0]) {
  66                 int ret;
  67                 snprintf(cmd, sizeof(cmd), "doc:cmd%s", s-1);
  68                 ret = call(cmd, ci->focus, ci->num, ci->mark);
  69                 switch(ret) {
  70                 case 0:
  71                         snprintf(cmd, sizeof(cmd),
  72                                  "Unknown command `%s'", s);
  73                         call("Message:modal", ci->focus, 0, NULL, cmd);
  74                         break;
  75                 case 2: /* request to move to next line */
  76                         call("K:Down", ci->focus, ci->num, ci->mark);
  77                         break;
  78                 case 3: /* request to move to previous line */
  79                         call("K:Up", ci->focus, ci->num, ci->mark);
  80                         break;
  81                 }
  82         }
  83         return 1;
  84 }
  85
  86 DEF_CMD(viewer_page_down)
  87 {
  88         struct viewer_data *vd = ci->home->data;
  89
  90         if (!vd->active)
  91                 return Efallthrough;
  92         call("K:Next", ci->focus, ci->num, ci->mark);
  93         return 1;
  94 }
  95
  96 DEF_CMD(viewer_page_up)
  97 {
  98         struct viewer_data *vd = ci->home->data;
  99
 100         if (!vd->active)
 101                 return Efallthrough;
 102         call("K:Prior", ci->focus, ci->num, ci->mark);
 103         return 1;
 104 }
 105
 106 DEF_CMD(viewer_bury)
 107 {
 108         /* First see if doc wants to handle 'q' */
 109         int ret;
 110         struct viewer_data *vd = ci->home->data;
 111
 112         if (!vd->active)
 113                 return Efallthrough;
 114
 115         ret = call("doc:cmd-q", ci->focus, ci->num, ci->mark);
 116         switch (ret) {
 117         case 0:
 118                 call("Window:bury", ci->focus);
 119                 break;
 120         case 2: /* request to move to next line */
 121                 call("K:Down", ci->focus, ci->num, ci->mark);
 122                 break;
 123         case 3: /* request to move to previous line */
 124                 call("K:Up", ci->focus, ci->num, ci->mark);
 125                 break;
 126         }
 127         return 1;
 128 }
 129
 130 DEF_CMD(viewer_deactivate)
 131 {
 132         struct viewer_data *vd = ci->home->data;
 133
 134         if (!vd->active)
 135                 return Efallthrough;
 136         vd->active = False;
 137         return 1;
 138 }
 139
 140 DEF_CMD(viewer_activate)
 141 {
 142         struct viewer_data *vd = ci->home->data;
 143
 144         vd->active = True;
 145         return 1;
 146 }
 147
 148 DEF_CMD(viewer_clone)
 149 {
 150         struct pane *p;
 151         struct viewer_data *vd = ci->home->data;
 152
 153         if (vd->active)
 154                 p = do_viewer_attach(ci->focus);
 155         else
 156                 p = ci->focus;
 157         pane_clone_children(ci->home, p);
 158         return 1;
 159 }
 160
 161 DEF_CMD(viewer_appeared)
 162 {
 163         char *t = pane_attr_get(ci->focus, "doc-type");
 164         if (t && strcmp(t, "text") == 0)
 165                 attr_set_str(&ci->focus->attrs, "view-cmd-V", "viewer");
 166         return Efallthrough;
 167 }
 168
 169 void edlib_init(struct pane *ed safe)
 170 {
 171         viewer_map = key_alloc();
 172
 173         key_add(viewer_map, "Replace", &no_replace);
 174         key_add_range(viewer_map, "doc:char- ", "doc:char-~", &viewer_cmd);
 175         key_add(viewer_map, "K:Enter", &viewer_cmd);
 176         key_add(viewer_map, "doc:char- ", &viewer_page_down);
 177         key_add(viewer_map, "K:C-H", &viewer_page_up);
 178         key_add(viewer_map, "K:Backspace", &viewer_page_up);
 179         key_add(viewer_map, "K:Del", &viewer_page_up);
 180         key_add(viewer_map, "doc:char-q", &viewer_bury);
 181         key_add(viewer_map, "doc:char-E", &viewer_deactivate);
 182         key_add(viewer_map, "Clone", &viewer_clone);
 183         key_add(viewer_map, "attach-viewer", &viewer_activate);
 184
 185         call_comm("global-set-command", ed, &viewer_attach, 0, NULL,
 186                   "attach-viewer");
 187         call_comm("global-set-command", ed, &viewer_appeared, 0, NULL,
 188                   "doc:appeared-viewer");
 189
 190         /* FIXME this doesn't seem quite right...
 191          * The goal is that if 'viewer' is requested of doc:attach-pane,
 192          * this pane gets attached, in place of any default.
 193          * I'm not sure it should be "in-place", and I feel it should be easier
 194          * to over-ride..
 195          */
 196         attr_set_str(&ed->attrs, "view-viewer", "viewer");
 197 }