attachments: link/unlink from the TUI, multi-voucher linksv0.1.29

The voucher detail can attach a file to an existing voucher (^F) and
the underlag picker (f) can remove a link (d, confirmed). The Underlag
inbox links a highlighted item to a voucher picked from a list (k).

attachment.link and attachment.unlink are new write commands (dry-run,
audited); unlinked files return to the inbox. The same content may now
link to several vouchers — only the same voucher/attachment pair is a
CONFLICT, matching the table's primary key.

1 files changed, 81 insertions, 6 deletions

diff --git a/src/commands.c b/src/commands.c
index e16ba75..d7f3860 100644
--- a/src/commands.c
+++ b/src/commands.c
@@ -3185,14 +3185,15 @@ static yyjson_mut_val *h_voucher_correct(struct req *r)
 /* ------------------------------------------------------------------ */
 
 static int link_attachment(struct req *r, int64_t aid, int64_t vid,
-                           char **errmsg)
+                           char **errmsg, const char **errcode)
 {
+    *errcode = "INTERNAL";
     sqlite3_stmt *st = NULL;
     if (sqlite3_prepare_v2(
             r->db,
             "SELECT (SELECT count(*) FROM vouchers WHERE org_id=?1 AND id=?2),"
             "(SELECT count(*) FROM voucher_attachments WHERE org_id=?1"
-            " AND attachment_id=?3),"
+            " AND voucher_id=?2 AND attachment_id=?3),"
             "(SELECT count(*) FROM attachments WHERE org_id=?1 AND id=?3)",
             -1, &st, NULL) != SQLITE_OK) {
         *errmsg = xstrdup("database error");
@@ -3210,14 +3211,17 @@ static int link_attachment(struct req *r, int64_t aid, int64_t vid,
     sqlite3_finalize(st);
     if (!aexists) {
         *errmsg = xstrdup("attachment not found");
+        *errcode = "NOT_FOUND";
         return -1;
     }
     if (!vexists) {
         *errmsg = xstrdup("voucher not found");
+        *errcode = "NOT_FOUND";
         return -1;
     }
     if (linked) {
         *errmsg = xstrdup("attachment is already linked");
+        *errcode = "CONFLICT";
         return -1;
     }
     char ts[32];
@@ -3290,8 +3294,10 @@ static yyjson_mut_val *h_attachment_put(struct req *r)
         free(content);
         if (voucher_id) {
             char *emsg = NULL;
-            if (link_attachment(r, existing, voucher_id, &emsg) != 0) {
-                yyjson_mut_val *res = fail(r, "CONFLICT", emsg);
+            const char *ecode = NULL;
+            if (link_attachment(r, existing, voucher_id, &emsg, &ecode) != 0) {
+                yyjson_mut_val *res =
+                    fail(r, ecode ? ecode : "INTERNAL", emsg);
                 free(emsg);
                 return res;
             }
@@ -3331,8 +3337,9 @@ static yyjson_mut_val *h_attachment_put(struct req *r)
 
     if (voucher_id) {
         char *emsg = NULL;
-        if (link_attachment(r, id, voucher_id, &emsg) != 0) {
-            yyjson_mut_val *res = fail(r, "NOT_FOUND", emsg);
+        const char *ecode = NULL;
+        if (link_attachment(r, id, voucher_id, &emsg, &ecode) != 0) {
+            yyjson_mut_val *res = fail(r, ecode ? ecode : "INTERNAL", emsg);
             free(emsg);
             return res;
         }
@@ -3347,6 +3354,70 @@ static yyjson_mut_val *h_attachment_put(struct req *r)
     return o;
 }
 
+static yyjson_mut_val *h_attachment_link(struct req *r)
+{
+    int64_t id = 0, voucher_id = 0;
+    arg_int(r->args, "id", &id);
+    arg_int(r->args, "voucher_id", &voucher_id);
+    if (id <= 0 || voucher_id <= 0)
+        return fail(r, "INVALID_ARGS", "id and voucher_id are required");
+    if (r->dry_run) {
+        yyjson_mut_val *o = yyjson_mut_obj(r->rdoc);
+        yyjson_mut_obj_add_bool(r->rdoc, o, "dry_run", true);
+        return o;
+    }
+    char *emsg = NULL;
+    const char *ecode = NULL;
+    if (link_attachment(r, id, voucher_id, &emsg, &ecode) != 0) {
+        yyjson_mut_val *e = fail(r, ecode ? ecode : "INTERNAL", emsg);
+        free(emsg);
+        return e;
+    }
+    char *reqjson = audit_args_json(r->args);
+    audit_append(r->db, r->org_id, r->sess->user_id, r->sess->token_id,
+                 "attachment.link", reqjson, "OK", NULL);
+    free(reqjson);
+    yyjson_mut_val *o = yyjson_mut_obj(r->rdoc);
+    yyjson_mut_obj_add_int(r->rdoc, o, "id", id);
+    yyjson_mut_obj_add_int(r->rdoc, o, "voucher_id", voucher_id);
+    return o;
+}
+
+static yyjson_mut_val *h_attachment_unlink(struct req *r)
+{
+    int64_t id = 0, voucher_id = 0;
+    arg_int(r->args, "id", &id);
+    arg_int(r->args, "voucher_id", &voucher_id);
+    if (id <= 0 || voucher_id <= 0)
+        return fail(r, "INVALID_ARGS", "id and voucher_id are required");
+    if (r->dry_run) {
+        yyjson_mut_val *o = yyjson_mut_obj(r->rdoc);
+        yyjson_mut_obj_add_bool(r->rdoc, o, "dry_run", true);
+        return o;
+    }
+    sqlite3_stmt *st = NULL;
+    if (sqlite3_prepare_v2(
+            r->db,
+            "DELETE FROM voucher_attachments WHERE org_id=?1"
+            " AND voucher_id=?2 AND attachment_id=?3",
+            -1, &st, NULL) != SQLITE_OK)
+        return fail(r, "INTERNAL", "database error");
+    sqlite3_bind_int64(st, 1, r->org_id);
+    sqlite3_bind_int64(st, 2, voucher_id);
+    sqlite3_bind_int64(st, 3, id);
+    int rc = sqlite3_step(st);
+    sqlite3_finalize(st);
+    if (rc != SQLITE_DONE)
+        return fail(r, "INTERNAL", sqlite3_errmsg(r->db));
+    if (sqlite3_changes(r->db) == 0)
+        return fail(r, "NOT_FOUND", "link not found");
+    char *reqjson = audit_args_json(r->args);
+    audit_append(r->db, r->org_id, r->sess->user_id, r->sess->token_id,
+                 "attachment.unlink", reqjson, "OK", NULL);
+    free(reqjson);
+    return yyjson_mut_obj(r->rdoc);
+}
+
 static yyjson_mut_val *h_attachment_get(struct req *r)
 {
     int64_t id = 0;
@@ -3844,6 +3915,10 @@ const struct command g_commands[] = {
       h_template_archive },
     { "attachment.put", "Store an underlag (receipt, invoice)", PERM_WRITE, 1,
       1, 1, h_attachment_put },
+    { "attachment.link", "Link an existing attachment to a voucher",
+      PERM_WRITE, 1, 1, 1, h_attachment_link },
+    { "attachment.unlink", "Remove an attachment link", PERM_WRITE, 1, 1, 1,
+      h_attachment_unlink },
     { "attachment.get", "Fetch an attachment", PERM_READ, 1, 0, 0,
       h_attachment_get },
     { "attachment.list", "List attachments / inbox", PERM_READ, 1, 0, 0,