Keep a surface's app in a store

Every surface takes --store PATH and runs the app on Pure's tree store,
so a list typed in the terminal is there the next time, on any surface.
Vega and the app carry no saving code; Vega saves the last frame changes
when it ends.

Checks let the CLI and the sentence surface take turns on one store and
match the model each time, and reopen an interactive session's store.

1 files changed, 23 insertions, 8 deletions

diff --git a/src/main.c b/src/main.c
index 3c3ba0f..1d8cc4b 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,5 +1,7 @@
 #define _DEFAULT_SOURCE
 #include "vega.h"
+#include "module-store.h"
+#include "store.h"
 #include <poll.h>
 #include <signal.h>
 #include <stdlib.h>
@@ -8,11 +10,13 @@
 #include <termios.h>
 #include <unistd.h>
 
-/* vega SURFACE MODULE: one module, one screen, several surfaces.
+/* vega SURFACE MODULE [--store PATH]: one module, one screen, several surfaces.
  *   tui              interactive terminal
  *   tui --dump WxH   the terminal's frames as text, driven by a script
  *   cli              plain lines for pipes, driven by a script
  *   say              sentences (the first natural-language surface), driven by a script
+ * With --store the app's states live in that tree store: the app continues
+ * where it was, whichever surface runs it.
  * Script commands, one per line: key KEYNAME | text HEX|- | type HEX | enter |
  * tab | frame [N] | show. key presses and releases the input bound to that key;
  * text commits text to the screen's text input; type, enter and tab act on the
@@ -25,7 +29,7 @@ static char entry[VEGA_TEXT];
 static size_t entry_length;
 static bool typing;
 
-static bool load(const char *path) {
+static bool load(const char *path, const char *store) {
     static unsigned char bytes[1 << 17];
     FILE *file = fopen(path, "rb");
     size_t size = file ? fread(bytes, 1, sizeof(bytes), file) : 0;
@@ -37,7 +41,9 @@ static bool load(const char *path) {
         fprintf(stderr, "vega: %s: %s\n", path, error);
         return false;
     }
-    if (pure_app_start(&app, &module, (PureData){0}) != PURE_OK) { fprintf(stderr, "vega: cannot start\n"); return false; }
+    if (store && pure_store_init(store) != PURE_OK) { fprintf(stderr, "vega: cannot open store %s\n", store); return false; }
+    PureResult started = pure_app_start(&app, &module, store ? pure_tree_data(store) : (PureData){0});
+    if (started != PURE_OK) { fprintf(stderr, "vega: cannot start (%d)\n", (int)started); return false; }
     vega_screen(&screen, &module);
     typing = screen.prompt >= 0;
     return true;
@@ -362,17 +368,26 @@ static int script(Surface surface, unsigned width, unsigned height) {
 
 int main(int argc, char **argv) {
     unsigned width = 0, height = 0;
-    bool dumped = argc == 5 && !strcmp(argv[3], "--dump") && sscanf(argv[4], "%ux%u", &width, &height) == 2 &&
-                  width && height && width <= 1000 && height <= 1000;
-    if ((argc != 3 && !dumped) || (dumped && strcmp(argv[1], "tui"))) {
-        fputs("vega tui|cli|say MODULE.pmod\nvega tui MODULE.pmod --dump WIDTHxHEIGHT < script\n", stderr);
+    bool dumped = false, usage = argc < 3 || argc % 2 == 0;
+    const char *store = NULL;
+    for (int i = 3; !usage && i + 1 < argc; i += 2) {
+        if (!strcmp(argv[i], "--store")) store = argv[i + 1];
+        else if (!strcmp(argv[i], "--dump") && sscanf(argv[i + 1], "%ux%u", &width, &height) == 2 && width && height &&
+                 width <= 1000 && height <= 1000) dumped = true;
+        else usage = true;
+    }
+    if (usage || (dumped && strcmp(argv[1], "tui"))) {
+        fputs("vega tui|cli|say MODULE.pmod [--store PATH]\n"
+              "vega tui MODULE.pmod [--store PATH] --dump WIDTHxHEIGHT < script\n", stderr);
         return 2;
     }
     Surface surface = !strcmp(argv[1], "cli") ? SURFACE_CLI : !strcmp(argv[1], "say") ? SURFACE_SAY :
                       !strcmp(argv[1], "tui") ? SURFACE_TUI : (Surface)-1;
     if ((int)surface < 0) { fprintf(stderr, "vega: unknown surface %s\n", argv[1]); return 2; }
-    if (!load(argv[2])) return 2;
+    if (!load(argv[2], store)) return 2;
     int status = surface == SURFACE_TUI && !dumped ? interactive() : script(surface, width, height);
+    /* Frame changes are stored with events; keep the last ones too. */
+    if (pure_app_save(&app) != PURE_OK) { fputs("vega: cannot save\n", stderr); status = status ? status : 1; }
     pure_app_stop(&app);
     return status;
 }