adding an ffmpeg.rs and thumbnailing fn

This module adds a bg_from_video function that takes uses the ffmpeg
binary to create thumbnails and adds them to the apps local data directory.

src/rust/ffmpeg.rs

@@ -0,0 +1,56 @@
+use dirs;
+use std::fs;
+use std::io::{self, Write};
+use std::path::{Path, PathBuf};
+use std::process::Command;
+use std::str;
+
+pub fn bg_from_video(video: &Path) -> PathBuf {
+    let video = PathBuf::from(video);
+    println!("{:?}", video);
+    println!("{:?}", video.file_name());
+    let mut data_dir = dirs::data_local_dir().unwrap();
+    data_dir.push("librepresenter");
+    data_dir.push("thumbnails");
+    if !data_dir.exists() {
+        fs::create_dir(&data_dir).expect("Could not create thumbnails dir");
+    }
+    let mut screenshot = data_dir.clone();
+    screenshot.push(video.file_name().unwrap());
+    screenshot.set_extension("png");
+    if !screenshot.exists() {
+        let output_duration = Command::new("ffprobe")
+            .args(&["-i", &video.to_string_lossy()])
+            .output()
+            .expect("failed to execute ffprobe");
+        let mut duration = String::from("");
+        let mut at_second: i32;
+        at_second = 2;
+        let mut log = str::from_utf8(&output_duration.stdout)
+            .expect("Using non UTF-8 characters")
+            .to_string();
+        if let Some(duration_index) = &log.find("Duration") {
+            duration = log.split_off(*duration_index + 10);
+            duration.truncate(11);
+            println!("rust-duration-is: {duration}");
+        }
+        let output = Command::new("ffmpeg")
+            .args(&[
+                "-i",
+                &video.to_string_lossy(),
+                "-ss",
+                &at_second.to_string(),
+                "-vframes",
+                "1",
+                "-y",
+                &screenshot.to_string_lossy(),
+            ])
+            .output()
+            .expect("failed to execute ffmpeg");
+        io::stdout().write_all(&output.stdout).unwrap();
+        io::stderr().write_all(&output.stderr).unwrap();
+    } else {
+        println!("Screenshot already exists");
+    }
+    screenshot
+}

src/rust/lib.rs

@@ -1,3 +1,4 @@
+pub mod ffmpeg;
 mod file_helper;
 pub mod image_model;
 pub mod models;

src/rust/slide_model.rs

@@ -124,26 +124,15 @@ mod slide_model {
 
     // use crate::video_thumbnail;
     // use image::{ImageBuffer, Rgba};
+    use crate::ffmpeg;
     use std::path::PathBuf;
     impl qobject::SlideyMod {
-        #[qinvokable]
-        pub fn video_thumbnail(
-            mut self: Pin<&mut Self>,
-            video: QString,
-            service_item_id: i32,
-            index: i32,
-        ) -> QString {
+        pub fn video_thumbnail(mut self: Pin<&mut Self>, video: &QString) -> QString {
             let video = video.to_string();
-            let mut path = PathBuf::from(video);
-            println!("{:?}", path);
-            // let mut image_iter = video_thumbnail::ImageIter::new(path)?;
-            // image_iter.seek(2.0);
+            let path = PathBuf::from(video);
+            let video = ffmpeg::bg_from_video(&path);
 
-            // if let Some(image) = image_iter.next() {
-            //     image.save("image.jpg");
-            // }
-
-            QString::default()
+            QString::from(video.to_str().unwrap())
         }
 
         #[qinvokable]
@@ -218,7 +207,16 @@ mod slide_model {
         fn add_slide(mut self: Pin<&mut Self>, slide: &Slidey) {
             let index = self.as_ref().slides().len() as i32;
             println!("{:?}", slide);
-            let slide = slide.clone();
+            let mut slide = slide.clone();
+            if !&slide.video_background.is_empty() {
+                slide.video_thumbnail = self
+                    .as_mut()
+                    .video_thumbnail(&slide.video_background)
+                    .insert(0, &QString::from("file://"))
+                    .to_owned();
+                println!("rust-inserted: {:?}", slide.video_thumbnail);
+            }
+
             unsafe {
                 self.as_mut()
                     .begin_insert_rows(&QModelIndex::default(), index, index);
@@ -230,6 +228,14 @@ mod slide_model {
         fn insert_slide(mut self: Pin<&mut Self>, slide: &Slidey, id: i32) {
             let mut slide = slide.clone();
             slide.slide_index = id;
+            if !&slide.video_background.is_empty() {
+                slide.video_thumbnail = self
+                    .as_mut()
+                    .video_thumbnail(&slide.video_background)
+                    .insert(0, &QString::from("file://"))
+                    .to_owned();
+                println!("rust-inserted: {:?}", slide.video_thumbnail);
+            }
 
             unsafe {
                 self.as_mut()