1 files changed, 67 insertions, 8 deletions

diff --git a/src/download.c b/src/download.c
index 4154dcb..3b3692c 100644
--- a/src/download.c
+++ b/src/download.c
@@ -1,32 +1,91 @@
 #include "download.h"
 #include "buffer.h"
 #include "program.h"
+#include "fallback.h"
+#include <stdio.h>
+
+int download_to_buffer(const char *url, Buffer *buffer, fallback *fall) {
+    char new_url[2048];
+    snprintf(new_url, sizeof(new_url), "%s", url);
+
+    fallback_item *fall_item = NULL;
+    if(fall) {
+        fall_item = fallback_get_from_url(fall, url);
+        if(fall_item && fall_item->source_to_use)
+            fallback_item_replace_url_with_fallback_url(fall_item, url, new_url, sizeof(new_url));
+    }
 
-int download_to_buffer(const char *url, Buffer *buffer) {
     const char *args[] = {
         "curl", "-s", "-L", "-f",
         "-H", "user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36",
         "-H", "Accept-Language: en-US,en;q=0.5",
         "--compressed",
         "--",
-        url,
+        new_url,
         NULL
     };
+
     int result = program_exec(args, program_buffer_write_callback, buffer);
-    if(result != 0)
+    if(result == 0) {
+        buffer_append(buffer, "\0", 1);
+        return 0;
+    }
+
+    if(!fall || !fall_item || fall_item->source_to_use)
         return result;
-    buffer_append(buffer, "\0", 1);
-    return result;
+
+    const char **fallbacks_it = buffer_begin(&fall_item->fallbacks);
+    const char **fallbacks_end = buffer_end(&fall_item->fallbacks);
+    for(; fallbacks_it != fallbacks_end; ++fallbacks_it) {
+        buffer_clear(buffer);
+        fallback_replace_url_with_fallback_url(url, *fallbacks_it, new_url, sizeof(new_url));
+        if(download_to_buffer(new_url, buffer, NULL) == 0) {
+            fprintf(stderr, "Download failed for url %s, replacing domain with %s for this sync session\n", url, *fallbacks_it);
+            fall_item->source_to_use = *fallbacks_it;
+            return 0;
+        }
+    }
+
+    return -1;
 }
 
-int is_header_response_ok(const char *url) {
+int is_header_response_ok(const char *url, fallback *fall) {
+    char new_url[2048];
+    snprintf(new_url, sizeof(new_url), "%s", url);
+
+    fallback_item *fall_item = NULL;
+    if(fall) {
+        fall_item = fallback_get_from_url(fall, url);
+        if(fall_item && fall_item->source_to_use)
+            fallback_item_replace_url_with_fallback_url(fall_item, url, new_url, sizeof(new_url));
+    }
+
     const char *args[] = {
         "curl", "-s", "-L", "-f", "-I",
         "-H", "user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36",
         "-H", "Accept-Language: en-US,en;q=0.5",
         "--",
-        url,
+        new_url,
         NULL
     };
-    return program_exec(args, NULL, NULL);
+
+    int result = program_exec(args, NULL, NULL);
+    if(result == 0)
+        return 0;
+
+    if(!fall || !fall_item || fall_item->source_to_use)
+        return result;
+
+    const char **fallbacks_it = buffer_begin(&fall_item->fallbacks);
+    const char **fallbacks_end = buffer_end(&fall_item->fallbacks);
+    for(; fallbacks_it != fallbacks_end; ++fallbacks_it) {
+        fallback_replace_url_with_fallback_url(url, *fallbacks_it, new_url, sizeof(new_url));
+        if(is_header_response_ok(new_url, NULL) == 0) {
+            fprintf(stderr, "Download failed for url %s, replacing domain with %s for this sync session\n", url, *fallbacks_it);
+            fall_item->source_to_use = *fallbacks_it;
+            return 0;
+        }
+    }
+
+    return -1;
 }