feat: Lua Animations

Slap the ENTIRE LUA RUNTIME onto Ly

build.zig

@@ -71,6 +71,14 @@ pub fn build(b: *std.Build) !void {
         }),
     });
 
+    const zlua = b.dependency("zlua", .{
+        .target = target,
+        .optimize = optimize,
+    });
+    exe.root_module.addImport("zlua", zlua.module("zlua"));
+
+
+
     const ly_ui = b.dependency("ly_ui", .{
         .target = target,
         .optimize = optimize,

build.zig.zon

@@ -11,6 +11,10 @@
             .url = "git+https://github.com/Hejsil/zig-clap#fc1e5cc3f6d9d3001112385ee6256d694e959d2f",
             .hash = "clap-0.11.0-oBajB7foAQC3Iyn4IVCkUdYaOVVng5IZkSncySTjNig1",
         },
+        .zlua = .{
+            .url = "git+https://github.com/natecraddock/ziglua?ref=zig-0.16#8f271c82baa5fc43aa02a72f6da020c2025d9436",
+            .hash = "zlua-0.1.0-hGRpC2aABQD4D9PBVH3wAW8k32-I4969MRQ0CpOwoley",
+        },
     },
     .paths = .{
         "build.zig",

src/animations/Lua.zig

@@ -0,0 +1,151 @@
+const std = @import("std");
+const ly_ui = @import("ly-ui");
+const LogFile = ly_ui.ly_core.LogFile;
+const Widget = ly_ui.Widget;
+const TerminalBuffer = ly_ui.TerminalBuffer;
+const Cell = ly_ui.Cell;
+const Allocator = std.mem.Allocator;
+
+const zlua = @import("zlua");
+
+const LyLua = @embedFile("ly.lua");
+
+const Lua = @This();
+
+
+instance: ?Widget = null,
+lua: *zlua.Lua,
+log: *LogFile,
+terminal_buffer: *TerminalBuffer,
+io: std.Io,
+
+lua_error: bool = false,
+
+pub fn init(
+    io: std.Io,
+    alloc: Allocator,
+    log: *LogFile,
+    buf: *TerminalBuffer,
+    file: ?[]const u8,
+) !Lua {
+    var self: Lua = .{
+        .lua = try zlua.Lua.init(alloc),
+        .terminal_buffer = buf,
+        .instance = null,
+        .log = log,
+        .io = io,
+    };
+    self.lua.openLibs();
+    if (file) |f| {
+        const zf = std.mem.concatWithSentinel(alloc, u8, &[1][]const u8{f}, 0) catch unreachable;
+        defer alloc.free(zf);
+        self.lua.doString(LyLua) catch {
+            const errorStr = self.lua.toString(-1) catch unreachable;
+            self.log.err(self.io, "Lua", "Lua Error: {s}", .{errorStr}) catch unreachable;
+            self.lua.setGlobal("_ERROR");
+            self.lua_error = true;
+        };
+        self.lua.doFile(zf) catch {
+            const errorStr = self.lua.toString(-1) catch unreachable;
+            self.log.err(self.io, "Lua", "Lua Error: {s}", .{errorStr}) catch unreachable;
+            self.lua.setGlobal("_ERROR");
+            self.lua_error = true;
+        };
+    }
+    _ = self.lua.getGlobal("ly");
+    addFuncToTable(self.lua, "putCell", luaPutCell);
+    self.lua.setGlobal("ly");
+
+    return self;
+}
+
+fn draw(self: *Lua) void {
+    _ = self.lua.getGlobal("ly");
+        _ =self.lua.pushString("width");
+        self.lua.pushInteger(@intCast(self.terminal_buffer.width));
+    self.lua.setTable(-3);
+        _ =self.lua.pushString("height");
+        self.lua.pushInteger(@intCast(self.terminal_buffer.height));
+    self.lua.setTable(-3);
+
+    self.lua.setGlobal("ly");
+    if (!self.lua_error) {
+        self.lua.doString(
+            "draw()"
+        ) catch {
+            const errorStr = self.lua.toString(-1) catch unreachable;
+            self.log.err(self.io, "Lua", "Lua Error: {s}", .{errorStr}) catch unreachable;
+            self.lua.setGlobal("_ERROR");
+            self.lua_error = true;
+        };
+    } else {
+        // set the entire background to red
+        const cell = Cell.init(0x2588, 0x00ff0000, 0x00ff0000);
+        for (0..self.terminal_buffer.height) |y|
+            for (0..self.terminal_buffer.width) |x|
+                cell.put(x, y) catch {};
+    }
+}
+
+fn calculateTimeout(self: *Lua, _: *anyopaque) !?usize {
+    const lyType = self.lua.getGlobal("ly"); // +1
+    _ = self.lua.pushString("frame_delay"); // + 1
+    if (lyType != .table) 
+        std.debug.panic("Lua: global 'ly' must be a table: got {}", .{lyType});
+    const frameDelayType = self.lua.getTable(-2); // neut
+    if (frameDelayType != .number)
+        std.debug.panic("Lua: 'ly.frame_delay' must be a number: got {}", .{frameDelayType});
+    const timeout = try self.lua.toNumeric(usize, -1);
+    self.lua.pop(-1); // pop number from stack
+    self.lua.pop(-1); // pop table 'ly' from stack
+    return timeout;
+}
+
+fn deinit(self: *Lua) void {
+    self.lua.deinit();
+}
+
+pub fn widget(self: *Lua) *Widget {
+    if (self.instance) |*inst| return inst;
+    self.instance = Widget.init(
+        "Lua",
+        null,
+        self,
+        deinit, //deinit
+        null, //realloc
+        draw, //draw
+        null, //update
+        null,
+        calculateTimeout, //calculateTimeout
+    );
+    return &self.instance.?;
+}
+
+fn luaPutCell(lua: ?*zlua.LuaState) callconv(.c) c_int {
+    var vm = @as(*zlua.Lua, @ptrCast(lua));
+    const cell = vm.checkNumeric(u32, 1);
+    const fg = vm.checkNumeric(u32, 2);
+    const bg = vm.checkNumeric(u32, 3);
+    const x = vm.checkNumeric(usize, 4);
+    const y = vm.checkNumeric(usize, 5);
+    Cell.init(cell, fg, bg).put(x, y) catch {};
+
+    return 0; // This function doesnt return anything
+} 
+
+/// Adds member function `name` to table at the top of the stack
+///
+/// Pushes: 0
+/// Pops: 0, this function can be called continuously
+/// Errors: unknown
+fn addFuncToTable(
+             vm:   *zlua.Lua,
+    comptime name: []const u8,
+             func: zlua.CFn, 
+) void 
+{
+    _ = vm.pushString(name);
+    vm.pushFunction(func);
+    vm.setTable(-3);
+}
+

src/animations/ly.lua

@@ -0,0 +1,3 @@
+ly = {
+	frame_delay = 0,
+}

src/config/Config.zig

@@ -74,6 +74,7 @@ lang: []const u8 = "en",
 login_cmd: ?[]const u8 = null,
 login_defs_path: []const u8 = "/etc/login.defs",
 logout_cmd: ?[]const u8 = null,
+lua_animation_file: ?[]const u8 = null,
 ly_log: ?[]const u8 = "/var/log/ly.log",
 margin_box_h: u8 = 2,
 margin_box_v: u8 = 1,

src/enums.zig

@@ -7,6 +7,7 @@ pub const Animation = enum {
     colormix,
     gameoflife,
     dur_file,
+    lua,
 };
 
 pub const DisplayServer = enum {

src/main.zig

@@ -29,6 +29,7 @@ const Doom = @import("animations/Doom.zig");
 const DurFile = @import("animations/DurFile.zig");
 const GameOfLife = @import("animations/GameOfLife.zig");
 const Matrix = @import("animations/Matrix.zig");
+const LuaAnim = @import("animations/Lua.zig");
 const auth = @import("auth.zig");
 const InfoLine = @import("components/InfoLine.zig");
 const Session = @import("components/Session.zig");
@@ -1098,6 +1099,16 @@ pub fn main(init: std.process.Init) !void {
             );
             animation = dur.widget();
         },
+        .lua => {
+            var lua = try LuaAnim.init(
+                state.io,
+                state.allocator,
+                &state.log_file,
+                &state.buffer,
+                state.config.lua_animation_file,
+            );
+            animation = lua.widget();
+        },
     }
     defer if (animation) |a| a.deinit();