allow images to upload and sort if according to their datetime

1 files changed, 60 insertions, 19 deletions

diff --git a/src/storage/image-manager/root.zig b/src/storage/image-manager/root.zig
index 7742df2..7fa1607 100644
--- a/src/storage/image-manager/root.zig
+++ b/src/storage/image-manager/root.zig
@@ -1,24 +1,30 @@
 const std = @import("std");
 
-const Storage = @import("../root.zig");
+const memora = @import("memora");
+const Storage = memora.Storage;
 pub const Image = @import("image.zig");
 
 const Self = @This();
 
 pub const empty: Self = .{};
 
-items: std.ArrayList(Image) = .empty,
-rw_lock: std.Thread.RwLock = .{},
+const Timestamp = struct {
+    index: usize,
+    node: std.DoublyLinkedList.Node,
 
-pub const LockedImages = struct {
-    images: []Image,
-    rw_lock: *std.Thread.RwLock,
+    pub fn next(self: *Timestamp) ?*Timestamp {
+        return @fieldParentPtr("node", self.node.next orelse return null);
+    }
 
-    pub fn deinit(self: *const @This()) void {
-        self.rw_lock.unlockShared();
+    pub fn prev(self: *Timestamp) ?*Timestamp {
+        return @fieldParentPtr("node", self.node.prev orelse return null);
     }
 };
 
+items: std.ArrayList(Image) = .empty,
+rw_lock: std.Thread.RwLock = .{},
+timestamp_order: std.DoublyLinkedList = .{},
+
 pub fn init(
     self: *Self,
     storage: *Storage,
@@ -35,32 +41,67 @@ pub fn init(
 
     while (try iterator.next()) |entry| {
         if (entry.kind == .file and std.mem.endsWith(u8, entry.name, ".jpg")) {
-            try self.items.append(
+            try self.add(
                 storage.allocator,
-                try .init(storage.allocator, entry.name[0..entry.name.len - 4])
+                try .init(storage, entry.name[0..entry.name.len - 4])
             );
         }
     }
 }
 
-pub fn add(
+pub fn add(self: *Self, allocator: std.mem.Allocator, image: Image) !void {
+    self.rw_lock.lock();
+    defer self.rw_lock.unlock();
+
+    try self.items.append(
+        allocator,
+        image,
+    );
+
+    var current = self.timestamp_order.first;
+
+    if (current == null) {
+        const timestamp = try allocator.create(Timestamp);
+        timestamp.index = self.items.items.len - 1;
+        self.timestamp_order.append(&timestamp.node);
+        return;
+    }
+
+    while (current) |c| {
+        const index = @as(*Timestamp, @fieldParentPtr("node", c)).index;
+        if (image.timestamp orelse 0 > self.items.items[index].timestamp orelse 0) {
+            const timestamp = try allocator.create(Timestamp);
+            timestamp.index = self.items.items.len - 1;
+            self.timestamp_order.insertBefore(c, &timestamp.node);
+            break;
+        }
+
+        current = c.next;
+    }
+}
+
+pub fn save(
     self: *Self,
     storage: *Storage,
     reader: *std.Io.Reader,
     size: usize,
 ) !void {
-    self.rw_lock.lock();
-    defer self.rw_lock.unlock();
+    return self.add(storage.allocator, try Image.new(storage, reader, size));
+}
 
-    try self.items.append(
-        storage.allocator,
-        try Image.new(storage, reader, size),
-    );
+pub fn list(self: *Self) memora.locked.Shared([]Image) {
+    self.rw_lock.lockShared();
+    return .{
+        .value = self.items.items,
+        .rw_lock = &self.rw_lock,
+    };
 }
 
-pub fn list(self: *Self) LockedImages {
+pub fn first_by_timestamp(self: *Self) memora.locked.Shared(?*Timestamp) {
+    self.rw_lock.lockShared();
     return .{
-        .images = self.items.items,
+        .value = if (self.timestamp_order.first) |first| @fieldParentPtr("node", first)
+        else null,
         .rw_lock = &self.rw_lock,
     };
 }