Add checks for updating of packages

src/installer.rs

@@ -94,8 +94,24 @@ impl InstallerFramework {
                 .expect("Install directory not initialised")
         );
 
+        // Calculate packages to *uninstall*
+        let mut uninstall_items = Vec::new();
+        if !fresh_install {
+            for package in &self.database {
+                if !items.contains(&package.name) {
+                    uninstall_items.push(package.name.clone());
+                }
+            }
+
+            println!(
+                "Framework: Uninstalling {:?} additionally.",
+                uninstall_items
+            );
+        }
+
         let task = Box::new(InstallTask {
             items,
+            uninstall_items,
             fresh_install,
         });
 

src/tasks/download_pkg.rs

@@ -19,11 +19,10 @@ impl Task for DownloadPackageTask {
     fn execute(
         &mut self,
         mut input: Vec<TaskParamType>,
-        _: &mut InstallerFramework,
+        context: &mut InstallerFramework,
         messenger: &Fn(&str, f32),
     ) -> Result<TaskParamType, String> {
         assert_eq!(input.len(), 1);
-        messenger(&format!("Downloading package {:?}...", self.name), 0.0);
 
         let file = input.pop().expect("Should have input from resolver!");
         let (version, file) = match file {
@@ -31,6 +30,19 @@ impl Task for DownloadPackageTask {
             _ => return Err(format!("Unexpected param type to download package")),
         };
 
+        // Check to see if this is the newest file available already
+        for element in &context.database {
+            if element.name == self.name {
+                if element.version == version {
+                    println!("{:?} is already up to date.", self.name);
+                    return Ok(TaskParamType::Break);
+                }
+                break;
+            }
+        }
+
+        messenger(&format!("Downloading package {:?}...", self.name), 0.0);
+
         let mut downloaded = 0;
         let mut data_storage: Vec<u8> = Vec::new();
 

src/tasks/install.rs

@@ -6,12 +6,14 @@ use tasks::install_dir::VerifyInstallDirTask;
 use tasks::install_pkg::InstallPackageTask;
 use tasks::save_database::SaveDatabaseTask;
 use tasks::save_executable::SaveExecutableTask;
+use tasks::uninstall_pkg::UninstallPackageTask;
 
 use tasks::Task;
 use tasks::TaskParamType;
 
 pub struct InstallTask {
     pub items: Vec<String>,
+    pub uninstall_items: Vec<String>,
     pub fresh_install: bool,
 }
 
@@ -37,6 +39,13 @@ impl Task for InstallTask {
             elements.push(Box::new(InstallPackageTask { name: item.clone() }));
         }
 
+        for item in &self.uninstall_items {
+            elements.push(Box::new(UninstallPackageTask {
+                name: item.clone(),
+                optional: false,
+            }));
+        }
+
         elements.push(Box::new(SaveDatabaseTask {}));
 
         if self.fresh_install {

src/tasks/install_pkg.rs

@@ -51,7 +51,12 @@ impl Task for InstallPackageTask {
             None => return Err(format!("Package {:?} could not be found.", self.name)),
         };
 
-        let _ = input.pop().expect("Should have input from uninstaller!");
+        // Check to see if no archive was available.
+        match input.pop().expect("Should have input from uninstaller!") {
+            // No file to install, but all is good.
+            TaskParamType::Break => return Ok(TaskParamType::None),
+            _ => {}
+        }
 
         let data = input.pop().expect("Should have input from resolver!");
         let (file, data) = match data {
@@ -97,20 +102,17 @@ impl Task for InstallPackageTask {
 
             // Create target file
             let target_path = path.join(&filename);
-            println!("target_path: {:?}", target_path);
-
-            installed_files.push(filename.to_string());
 
             // Check to make sure this isn't a directory
             if filename.ends_with("/") || filename.ends_with("\\") {
-                // Create this directory and move on
-                match create_dir_all(target_path) {
-                    Ok(v) => v,
-                    Err(v) => return Err(format!("Unable to create dir: {:?}", v)),
-                }
+                // Directory was already created
                 continue;
             }
 
+            println!("Creating file: {:?}", target_path);
+
+            installed_files.push(filename.to_string());
+
             let mut target_file = match File::create(target_path) {
                 Ok(v) => v,
                 Err(v) => return Err(format!("Unable to open file handle: {:?}", v)),

src/tasks/mod.rs

@@ -22,8 +22,12 @@ pub mod uninstall_pkg;
 /// An abstraction over the various paramaters that can be passed around.
 pub enum TaskParamType {
     None,
+    /// Metadata about a file
     File(Version, File),
+    /// Downloaded contents of a file
     FileContents(Version, Vec<u8>),
+    /// Tells the runtime to break parsing other dependencies
+    Break
 }
 
 /// A Task is a small, async task conforming to a fixed set of inputs/outputs.
@@ -89,13 +93,25 @@ impl DependencyTree {
         let mut count = 0;
 
         for i in &mut self.dependencies {
-            inputs.push(i.execute(context, &|msg: &str, progress: f32| {
+            let result = i.execute(context, &|msg: &str, progress: f32| {
                 messenger(
                     msg,
                     progress / total_tasks + (1.0 / total_tasks) * count as f32,
                 )
-            })?);
+            })?;
+
+            // Check to see if we skip matching other dependencies
+            let do_break = match &result {
+                &TaskParamType::Break => true,
+                _ => false
+            };
+
+            inputs.push(result);
             count += 1;
+
+            if do_break {
+                break;
+            }
         }
 
         self.task