From 3c65723a0fb23437467deee72d0ee5651e4db717 Mon Sep 17 00:00:00 2001
From: Maas-Maarten Zeeman <mmzeeman@xs4all.nl>
Date: Sat, 8 Jan 2022 17:04:47 +0100
Subject: [PATCH] Busy adding remaining and pagecount

---
 c_src/esqlite3_nif.c  | 31 +++++++++++++++++++++++++-----
 src/esqlite3.erl      | 44 ++++++++++++++++++++++++++++++++++++++++++-
 test/esqlite_test.erl |  2 ++
 3 files changed, 71 insertions(+), 6 deletions(-)

diff --git a/c_src/esqlite3_nif.c b/c_src/esqlite3_nif.c
index e0a47d7..c6c3421 100644
--- a/c_src/esqlite3_nif.c
+++ b/c_src/esqlite3_nif.c
@@ -734,7 +734,6 @@ do_column_types(ErlNifEnv *env, sqlite3_stmt *stmt)
 static ERL_NIF_TERM
 do_backup_init(ErlNifEnv *env, sqlite3 *db, const ERL_NIF_TERM arg)
 {
-    int rc;
     int tuple_arity;
     const ERL_NIF_TERM *elements;
     sqlite3_backup *backup;
@@ -800,13 +799,35 @@ do_backup_step(ErlNifEnv *env, const ERL_NIF_TERM arg)
 static ERL_NIF_TERM
 do_backup_remaining(ErlNifEnv *env, const ERL_NIF_TERM arg)
 {
-    return make_atom(env, "todo");
+    esqlite_backup *esqlite_backup;
+    int remaining;
+    ERL_NIF_TERM remaining_term;
+
+    if(!enif_get_resource(env, arg, esqlite_backup_type, (void **) &esqlite_backup)) {
+        return make_error_tuple(env, "invalid");
+    }
+
+    remaining = sqlite3_backup_remaining(esqlite_backup->backup);
+    remaining_term = enif_make_int64(env, remaining);
+
+    return make_ok_tuple(env, remaining_term);
 }
 
 static ERL_NIF_TERM
 do_backup_pagecount(ErlNifEnv *env, const ERL_NIF_TERM arg)
 {
-    return make_atom(env, "todo");
+    esqlite_backup *esqlite_backup;
+    int pagecount;
+    ERL_NIF_TERM pagecount_term;
+
+    if(!enif_get_resource(env, arg, esqlite_backup_type, (void **) &esqlite_backup)) {
+        return make_error_tuple(env, "invalid");
+    }
+
+    pagecount = sqlite3_backup_pagecount(esqlite_backup->backup);
+    pagecount_term = enif_make_int64(env, pagecount);
+
+    return make_ok_tuple(env, pagecount_term);
 }
 
 static ERL_NIF_TERM
@@ -1512,7 +1533,7 @@ esqlite_backup_remaining(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
 
     if(!enif_get_resource(env, argv[0], esqlite_connection_type, (void **) &conn))
         return enif_make_badarg(env);
-    // backup
+    // backup 1
     if(!enif_is_ref(env, argv[2]))
         return make_error_tuple(env, "invalid_ref");
     if(!enif_get_local_pid(env, argv[3], &pid))
@@ -1543,7 +1564,7 @@ esqlite_backup_pagecount(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
 
     if(!enif_get_resource(env, argv[0], esqlite_connection_type, (void **) &conn))
         return enif_make_badarg(env);
-    // backup
+    // backup 1
     if(!enif_is_ref(env, argv[2]))
         return make_error_tuple(env, "invalid_ref");
     if(!enif_get_local_pid(env, argv[3], &pid))
diff --git a/src/esqlite3.erl b/src/esqlite3.erl
index 32aa9d6..5d20f94 100644
--- a/src/esqlite3.erl
+++ b/src/esqlite3.erl
@@ -37,6 +37,8 @@
          column_names/1, column_names/2,
          column_types/1, column_types/2,
          backup_init/4, backup_init/5,
+         backup_remaining/1, backup_remaining/2,
+         backup_pagecount/1, backup_pagecount/2, 
          close/1, close/2,
          flush/0
         ]).
@@ -58,6 +60,7 @@
 }).
 
 -record(backup, {
+          raw_connection :: esqlite_nif:raw_connection(),
           raw_backup :: esqlite_nif:raw_backup()
 }).
 
@@ -544,7 +547,46 @@ backup_init(Dest, DestName, Src, SrcName) ->
 backup_init(#connection{raw_connection=Dest}, DestName, #connection{raw_connection=Src}, SrcName, Timeout) ->
     Ref = make_ref(),
     ok = esqlite3_nif:backup_init(Dest, DestName, Src, SrcName, Ref, self()),
-    receive_answer(Dest, Ref, Timeout).
+    case receive_answer(Dest, Ref, Timeout) of
+        {ok, RawBackup} when is_reference(RawBackup) ->
+            {ok, #backup{raw_connection=Dest, raw_backup=RawBackup}};
+        {error, _} = Error ->
+            Error
+    end.
+
+%% @doc Get the remaining number of pages which need to be backed up.
+-spec backup_remaining(backup()) -> {ok, pos_integer()} | {error, _}.
+backup_remaining(Backup) ->
+    backup_remaining(Backup, ?DEFAULT_TIMEOUT).
+
+%% @doc Get the remaining number of pages which need to be backed up.
+-spec backup_remaining(backup(), timeout()) -> {ok, pos_integer()} | {error, _}.
+backup_remaining(#backup{raw_connection=Conn, raw_backup=Back}, Timeout) ->
+    Ref = make_ref(),
+    ok = esqlite3_nif:backup_remaining(Conn, Back, Ref, self()),
+    case receive_answer(Conn, Ref, Timeout) of
+        {ok, R} when is_integer(R) ->
+            {ok, R};
+        {error, _}=E ->
+            E
+    end.
+
+%% @doc Get the remaining number of pages which need to be backed up.
+-spec backup_pagecount(backup()) -> {ok, pos_integer()} | {error, _}.
+backup_pagecount(Backup) ->
+    backup_pagecount(Backup, ?DEFAULT_TIMEOUT).
+
+%% @doc Get the remaining number of pages which need to be backed up.
+-spec backup_pagecount(backup(), timeout()) -> {ok, pos_integer()} | {error, _}.
+backup_pagecount(#backup{raw_connection=Conn, raw_backup=Back}, Timeout) ->
+    Ref = make_ref(),
+    ok = esqlite3_nif:backup_pagecount(Conn, Back, Ref, self()),
+    case receive_answer(Conn, Ref, Timeout) of
+        {ok, R} when is_integer(R) ->
+            {ok, R};
+        {error, _}=E ->
+            E
+    end.
 
 
 %% @doc Close the database
diff --git a/test/esqlite_test.erl b/test/esqlite_test.erl
index 7b20210..7e20d07 100644
--- a/test/esqlite_test.erl
+++ b/test/esqlite_test.erl
@@ -445,6 +445,8 @@ backup_test() ->
     {ok, Source} = esqlite3:open("test2.sql"),
 
     {ok, Backup} = esqlite3:backup_init(Dest, "main", Source, "main"),
+    {ok, 0} = esqlite3:backup_remaining(Backup),
+    {ok, 0} = esqlite3:backup_pagecount(Backup),
 
     ok.