quvi: coerce libquvi 0.4 support into allowing format switching

libquvi 0.4 doesn't allow us listing the formats supported by a
streaming site without doing additional network accesses, so switching
formats was not supported with it. (It's different with libquvi 0.9.)

But the most important case is switching between SD and HD. Usually,
--quvi-format=default will get SD, while --quvi-format=best gives HD.
Use this, and pretend that an URL supported by libquvi 0.4 supports both
of these. "cycle quvi-format" will switch between these. If the user
specifies something else via --quvi-format, this is included in the list
of switchable formats additionally to "default" and "best".

3 files changed, 30 insertions, 6 deletions

diff --git a/mpvcore/command.c b/mpvcore/command.c
index a5f66aae2b..a99dd3dcab 100644
--- a/mpvcore/command.c
+++ b/mpvcore/command.c
@@ -496,17 +496,22 @@ static int mp_property_edition(m_option_t *prop, int action, void *arg,
 }
 
 static struct mp_resolve_src *find_source(struct mp_resolve_result *res,
-                                          char *url)
+                                          char *encid, char *url)
 {
     if (res->num_srcs == 0)
         return NULL;
 
     int src = 0;
     for (int n = 0; n < res->num_srcs; n++) {
-        if (strcmp(res->srcs[n]->url, res->url) == 0) {
+        char *s_url = res->srcs[n]->url;
+        char *s_encid = res->srcs[n]->encid;
+        if (url && s_url && strcmp(url, s_url) == 0) {
             src = n;
             break;
         }
+        // Prefer source URL if possible; so continue in case encid isn't unique
+        if (encid && s_encid && strcmp(encid, s_encid) == 0)
+            src = n;
     }
     return res->srcs[src];
 }
@@ -514,11 +519,12 @@ static struct mp_resolve_src *find_source(struct mp_resolve_result *res,
 static int mp_property_quvi_format(m_option_t *prop, int action, void *arg,
                                    MPContext *mpctx)
 {
+    struct MPOpts *opts = mpctx->opts;
     struct mp_resolve_result *res = mpctx->resolve_result;
     if (!res || !res->num_srcs)
         return M_PROPERTY_UNAVAILABLE;
 
-    struct mp_resolve_src *cur = find_source(res, res->url);
+    struct mp_resolve_src *cur = find_source(res, opts->quvi_format, res->url);
     if (!cur)
         return M_PROPERTY_UNAVAILABLE;
 
diff --git a/mpvcore/resolve.h b/mpvcore/resolve.h
index 91684df250..7a60b29114 100644
--- a/mpvcore/resolve.h
+++ b/mpvcore/resolve.h
@@ -38,7 +38,7 @@ struct mp_resolve_result {
 };
 
 struct mp_resolve_src {
-    char *url;
+    char *url;       // can be NULL; otherwise it's the exact video URL
     char *encid;     // indicates quality level, contents are libquvi specific
 };
 
diff --git a/mpvcore/resolve_quvi.c b/mpvcore/resolve_quvi.c
index 9e98f2a992..00279c568f 100644
--- a/mpvcore/resolve_quvi.c
+++ b/mpvcore/resolve_quvi.c
@@ -23,6 +23,17 @@
 #include "mpvcore/options.h"
 #include "resolve.h"
 
+static void add_source(struct mp_resolve_result *res, const char *url,
+                       const char *encid)
+{
+    struct mp_resolve_src *src = talloc_ptrtype(res, src);
+    *src = (struct mp_resolve_src) {
+        .url = talloc_strdup(src, url),
+        .encid = talloc_strdup(src, encid),
+    };
+    MP_TARRAY_APPEND(res, res->srcs, res->num_srcs, src);
+}
+
 struct mp_resolve_result *mp_resolve_quvi(const char *url, struct MPOpts *opts)
 {
     QUVIcode rc;
@@ -49,14 +60,15 @@ struct mp_resolve_result *mp_resolve_quvi(const char *url, struct MPOpts *opts)
 
     mp_msg(MSGT_OPEN, MSGL_INFO, "[quvi] Checking URL...\n");
 
+    const char *req_format = opts->quvi_format ? opts->quvi_format : "best";
+
     // Can use quvi_query_formats() to get a list of formats like this:
     // "fmt05_240p|fmt18_360p|fmt34_360p|fmt35_480p|fmt43_360p|fmt44_480p"
     // (This example is youtube specific.)
     // That call requires an extra net access. quvi_next_media_url() doesn't
     // seem to do anything useful. So we can't really do anything useful
     // except pass through the user's format setting.
-    quvi_setopt(q, QUVIOPT_FORMAT, opts->quvi_format
-                                   ? opts->quvi_format : "best");
+    quvi_setopt(q, QUVIOPT_FORMAT, req_format);
 
     quvi_media_t m;
     rc = quvi_parse(q, (char *)url, &m);
@@ -89,5 +101,11 @@ struct mp_resolve_result *mp_resolve_quvi(const char *url, struct MPOpts *opts)
         result = NULL;
     }
 
+    // Useful for quvi-format cycling
+    add_source(result, NULL, "default");
+    add_source(result, NULL, "best");
+    if (strcmp(req_format, "best") != 0 && strcmp(req_format, "default") != 0)
+        add_source(result, NULL, req_format);
+
     return result;
 }