WIP v2: text works, primitives works in Lua

1 files changed, 449 insertions, 33 deletions

diff --git a/lua-bindings/src/lib.rs b/lua-bindings/src/lib.rs
index fcf307b..daf4b48 100644
--- a/lua-bindings/src/lib.rs
+++ b/lua-bindings/src/lib.rs
@@ -1,40 +1,149 @@
-use std::{sync::atomic::{AtomicUsize, Ordering}, cell::RefCell};
+use std::{
+    any::Any,
+    cell::RefCell,
+    sync::mpsc::{sync_channel, Receiver, SyncSender},
+    thread,
+};
 
 use diaphragm_cairo_renderer::CairoRenderer;
 use diaphragm_core::{
+    core_shapes::{CoreDrawable, CoreShape, Rectangle as CoreRectangle},
     solving::VariableHandle,
     text::{FontDescription as CoreFontDescription, FontStyle, FontWeight, Text as CoreText},
-    types::Float as CoreFloat,
+    types::{Bool as CoreBool, CoreShapeContext, Float as CoreFloat},
     Runtime,
 };
 use diaphragm_z3_solver::{z3, Z3Context};
 use mlua::prelude::*;
 
-static MAX_ID: AtomicUsize = AtomicUsize::new(0);
-
-thread_local! {
-    static SENDER: RefCell<Option<Runtime<'static>>> = RefCell::new(None);
-}
-
 #[derive(Clone, Copy, Debug)]
 struct Float(CoreFloat);
 
 impl Float {
     fn new() -> Float {
-        Float(CoreFloat::Variable(VariableHandle::new(
-            MAX_ID.fetch_add(1, Ordering::SeqCst),
-        )))
+        Float(runtime_thread_do(Box::new(|r| {
+            r.solver_ctx().new_free_float()
+        })))
+    }
+}
+impl LuaUserData for Float {
+    fn add_methods<'lua, M: LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
+        macro_rules! float_method {
+            ($name: expr, $op: ident) => {
+                methods.add_method($name, |_lua, lhs: &Float, rhs: LuaValue| {
+                    let lhs = *lhs;
+                    let rhs = Float::try_from(rhs).unwrap();
+                    Ok(Bool(runtime_thread_do(Box::new(move |r| {
+                        r.solver_ctx().$op(lhs.0, rhs.0)
+                    }))))
+                });
+            };
+        }
+
+        float_method!("eq", float_eq);
+        float_method!("ne", float_ne);
+        float_method!("gt", float_gt);
+        float_method!("ge", float_ge);
+        float_method!("lt", float_lt);
+        float_method!("le", float_le);
+    }
+}
+
+impl TryFrom<LuaValue<'_>> for Float {
+    type Error = LuaError;
+
+    fn try_from(value: LuaValue) -> Result<Self, Self::Error> {
+        match value {
+            LuaValue::Integer(i) => Ok(Float(CoreFloat::Fixed(i as _))),
+            LuaValue::Number(f) => Ok(Float(CoreFloat::Fixed(f))),
+            // Create a new float from the borrow, since it might already be borrowed, with for ex.
+            // f:eq(f)
+            LuaValue::UserData(u) => Ok(Float(u.borrow::<Float>().unwrap().0)),
+            _ => Err(LuaError::FromLuaConversionError {
+                from: "Value",
+                to: "Float",
+                message: Some("Only int, float, or float() values are allowed".to_string()),
+            }),
+        }
     }
 }
-impl LuaUserData for Float {}
 
 fn float(_: &Lua, _: ()) -> LuaResult<Float> {
     Ok(Float::new())
 }
 
+#[derive(Clone, Copy, Debug)]
+struct Bool(CoreBool);
+
+impl LuaUserData for Bool {
+    fn add_methods<'lua, M: LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
+        macro_rules! bool_method {
+            ($name: expr, $op: ident) => {
+                methods.add_method($name, |_lua, lhs: &Bool, rhs: LuaValue| {
+                    let lhs = *lhs;
+                    let rhs = Bool::try_from(rhs).unwrap();
+                    Ok(Bool(runtime_thread_do(Box::new(move |r| {
+                        r.solver_ctx().$op(lhs.0, rhs.0)
+                    }))))
+                });
+            };
+        }
+
+        bool_method!("eq", bool_eq);
+        bool_method!("implies", bool_implies);
+
+        methods.add_method("and", |_lua, lhs: &Bool, rhs: LuaValue| {
+            let lhs = *lhs;
+            let rhs = Bool::try_from(rhs).unwrap();
+            Ok(Bool(runtime_thread_do(Box::new(move |r| {
+                r.solver_ctx().bool_and(&[lhs.0, rhs.0])
+            }))))
+        });
+
+        methods.add_method("or", |_lua, lhs: &Bool, rhs: LuaValue| {
+            let lhs = *lhs;
+            let rhs = Bool::try_from(rhs).unwrap();
+            Ok(Bool(runtime_thread_do(Box::new(move |r| {
+                r.solver_ctx().bool_or(&[lhs.0, rhs.0])
+            }))))
+        });
+
+        methods.add_method("no", |_lua, b: &Bool, _: ()| {
+            let b = *b;
+            Ok(Bool(runtime_thread_do(Box::new(move |r| {
+                r.solver_ctx().bool_not(b.0)
+            }))))
+        });
+    }
+}
+
+impl TryFrom<LuaValue<'_>> for Bool {
+    type Error = LuaError;
+
+    fn try_from(value: LuaValue) -> Result<Self, Self::Error> {
+        match value {
+            LuaValue::Boolean(b) => Ok(Bool(runtime_thread_do(Box::new(move |r| {
+                r.solver_ctx().new_fixed_bool(b)
+            })))),
+            // Create a new bool from the borrow, since it might already be borrowed, with for ex.
+            // b:eq(b)
+            LuaValue::UserData(u) => Ok(Bool(u.borrow::<Bool>().unwrap().0)),
+            _ => Err(LuaError::FromLuaConversionError {
+                from: "Value",
+                to: "Bool",
+                message: Some("Only bool, or bool() values are allowed".to_string()),
+            }),
+        }
+    }
+}
+
 #[derive(Clone, Debug)]
 struct FontDescription(CoreFontDescription);
-impl LuaUserData for FontDescription {}
+impl LuaUserData for FontDescription {
+    fn add_fields<'lua, F: LuaUserDataFields<'lua, Self>>(fields: &mut F) {
+        fields.add_field_method_get("size", |_, this| Ok(Float(this.0.size)))
+    }
+}
 
 const DEFAULT_FONT_FAMILY: &str = "serif";
 
@@ -68,9 +177,10 @@ fn font(_: &Lua, params: LuaTable) -> LuaResult<FontDescription> {
         Some(_) => return Err(LuaError::RuntimeError("Unknown weight".to_string())),
     };
 
-    let size = params
-        .get::<_, Option<_>>("size")?
-        .unwrap_or_else(Float::new);
+    let size = match params.get::<_, Option<LuaValue>>("size")? {
+        Some(f) => Float::try_from(f)?,
+        None => Float::new(),
+    };
 
     Ok(FontDescription(CoreFontDescription {
         family,
@@ -80,46 +190,272 @@ fn font(_: &Lua, params: LuaTable) -> LuaResult<FontDescription> {
     }))
 }
 
+fn new_shape_context() -> CoreShapeContext {
+    runtime_thread_do(Box::new(|r| CoreShapeContext::new(r.solver_ctx())))
+}
+
+#[derive(Debug, Clone)]
+struct Drawable<T>
+where
+    T: Into<CoreShape>,
+{
+    shape: T,
+    context: CoreShapeContext,
+}
+
+trait HasContext {
+    fn get_context(&self) -> &CoreShapeContext;
+}
+
+fn add_bound_fields<'lua, T, F>(fields: &mut F)
+where
+    T: LuaUserData,
+    T: HasContext,
+    F: LuaUserDataFields<'lua, T>,
+{
+    macro_rules! bound_field {
+        ($name: expr, $method: ident) => {
+            fields.add_field_method_get($name, |_, this| {
+                let bounds = this.get_context().bounds().clone();
+                Ok(Float(runtime_thread_do(Box::new(move |r| {
+                    bounds.$method(r.solver_ctx())
+                }))))
+            })
+        };
+    }
+
+    bound_field!("top", top);
+    bound_field!("left", left);
+    bound_field!("width", width);
+    bound_field!("height", height);
+    bound_field!("right", right);
+    bound_field!("bottom", bottom);
+    bound_field!("vert_center", vert_center);
+    bound_field!("horiz_center", horiz_center);
+}
+
+impl<T: Into<CoreShape>> From<Drawable<T>> for CoreDrawable {
+    fn from(value: Drawable<T>) -> Self {
+        CoreDrawable::new(value.shape.into(), value.context)
+    }
+}
+
 #[derive(Clone, Debug)]
-struct Text(CoreText);
+struct Text(Drawable<CoreText>);
 impl LuaUserData for Text {
     fn add_methods<'lua, M: LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
         methods.add_method("draw", |_, this, _params: ()| {
-            println!("I'm drawing: {}", this.0.content);
+            let drawable = this.0.clone().into();
+            runtime_thread_do(Box::new(|r| {
+                r.add_drawable(drawable);
+            }));
             Ok(())
         })
     }
+
+    fn add_fields<'lua, F: LuaUserDataFields<'lua, Self>>(fields: &mut F) {
+        add_bound_fields(fields);
+    }
+}
+
+impl HasContext for Text {
+    fn get_context(&self) -> &CoreShapeContext {
+        &self.0.context
+    }
 }
 
 fn text(_: &Lua, params: LuaTable) -> LuaResult<Text> {
-    let content = params.get("content")?;
+    let content: String = params.get("content")?;
 
     let font = params
         .get::<_, Option<FontDescription>>("font")?
         .unwrap_or_default();
 
-    Ok(Text(CoreText {
-        content,
-        font: font.0,
+    let context = new_shape_context();
+
+    let content_2 = content.clone();
+    let font_2 = font.0.clone();
+    let context_2 = context.clone();
+
+    runtime_thread_do(Box::new(move |r| {
+        let (text_width, text_height) = r.renderer().text_extents(&content_2, &font_2);
+        let solver = r.solver_ctx();
+        // let scale = solver.float_div(font.0.size, CoreFloat::Fixed(height));
+
+        let calculated_width = solver.float_mul(&[CoreFloat::Fixed(text_width), font.0.size]);
+        let bounds_width = context_2.bounds().width(solver);
+        let width_constraint = solver.float_eq(bounds_width, calculated_width);
+        solver.constrain(width_constraint);
+
+        let calculated_height = solver.float_mul(&[CoreFloat::Fixed(text_height), font.0.size]);
+        let bounds_height = context_2.bounds().height(solver);
+        let height_constraint = solver.float_eq(bounds_height, calculated_height);
+        solver.constrain(height_constraint);
+    }));
+
+    Ok(Text(Drawable {
+        shape: CoreText {
+            content,
+            font: font.0,
+        },
+        context,
+    }))
+}
+
+#[derive(Clone, Debug)]
+struct Rectangle(Drawable<CoreRectangle>);
+impl LuaUserData for Rectangle {
+    fn add_methods<'lua, M: LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
+        methods.add_method("draw", |_, this, _params: ()| {
+            let drawable = this.0.clone().into();
+            runtime_thread_do(Box::new(|r| {
+                r.add_drawable(drawable);
+            }));
+            Ok(())
+        })
+    }
+
+    fn add_fields<'lua, F: LuaUserDataFields<'lua, Self>>(fields: &mut F) {
+        add_bound_fields(fields);
+    }
+}
+
+impl HasContext for Rectangle {
+    fn get_context(&self) -> &CoreShapeContext {
+        &self.0.context
+    }
+}
+
+fn rectangle(_: &Lua, _params: ()) -> LuaResult<Rectangle> {
+    Ok(Rectangle(Drawable {
+        shape: CoreRectangle {},
+        context: new_shape_context(),
     }))
 }
 
+thread_local! {
+    static SENDER: RefCell<Option<SyncSender<Message>>> = RefCell::new(None);
+    static REPLY: RefCell<Option<Receiver<Reply>>> = RefCell::new(None);
+    static REPLIER: RefCell<Option<SyncSender<Reply>>> = RefCell::new(None);
+}
+
+enum Message {
+    Do(Box<dyn FnOnce(&mut Runtime) + Send>),
+}
+
+fn runtime_thread_do<T: Any + Send>(fun: Box<dyn FnOnce(&mut Runtime) -> T + Send>) -> T {
+    SENDER.with(|sender| {
+        sender
+            .borrow_mut()
+            .as_mut()
+            .expect("Not currently drawing")
+            .send(Message::Do(Box::new(|r| {
+                let ret = fun(r);
+                REPLIER.with(|replier| {
+                    replier
+                        .borrow_mut()
+                        .as_mut()
+                        .unwrap()
+                        .send(Reply::Any(Box::new(ret)))
+                        .unwrap();
+                });
+            })))
+            .unwrap();
+    });
+
+    REPLY.with(|reply| {
+        let Reply::Any(any) = reply
+            .borrow_mut()
+            .as_mut()
+            .expect("Not currently drawing")
+            .recv()
+            .unwrap();
+        *any.downcast().unwrap()
+    })
+}
+
+enum Reply {
+    Any(Box<dyn Any + Send>),
+}
+
+fn constrain(_: &Lua, bool: Bool) -> LuaResult<()> {
+    runtime_thread_do(Box::new(move |r| r.solver_ctx().constrain(bool.0)));
+    Ok(())
+}
+
 fn draw(_: &Lua, params: LuaTable) -> LuaResult<()> {
-    let content: LuaTable = params.get("content")?;
-    let output: LuaTable = params.get("output")?;
+    // So.... The Z3 stuff isn't Send and contains lifetimes, so we can't store them in global
+    // variables or convert them to Lua. Solution: handle everything in a specific thread, and
+    // communicate through a channel.
+    thread::scope(|s| {
+        let (message_sender, message_receiver) = sync_channel(1);
+        let (reply_sender, reply_receiver) = sync_channel(1);
+
+        SENDER.with(|f| {
+            *f.borrow_mut() = Some(message_sender);
+        });
+
+        REPLY.with(|f| {
+            *f.borrow_mut() = Some(reply_receiver);
+        });
 
-    let z3_cfg = z3::Config::new();
-    let z3_ctx = z3::Context::new(&z3_cfg);
-    let ctx = Z3Context::new(&z3_ctx);
+        s.spawn(move || {
+            REPLIER.with(|f| {
+                *f.borrow_mut() = Some(reply_sender.clone());
+            });
 
-    let cairo_renderer = CairoRenderer::new();
+            let z3_cfg = z3::Config::new();
+            let z3_ctx = z3::Context::new(&z3_cfg);
+            let ctx = Z3Context::new(&z3_ctx);
 
-    // TODO: we shouldn't need the renderer until the end
-    let mut runtime = Runtime::new(Box::new(ctx), Box::new(cairo_renderer));
+            let cairo_renderer = CairoRenderer::new();
 
-    let _solver = runtime.solver_ctx();
+            // TODO: we shouldn't need the renderer until the end
+            let mut runtime = Runtime::new(Box::new(ctx), Box::new(cairo_renderer));
 
-    dbg!(content, output);
+            for message in message_receiver {
+                match message {
+                    Message::Do(fun) => {
+                        fun(&mut runtime);
+                    }
+                }
+            }
+
+            runtime.render();
+        });
+
+        let content: LuaValue = params.get("content").unwrap();
+        let _output: LuaTable = params.get("output").unwrap();
+
+        match content {
+            LuaValue::Table(table) => {
+                let () = table.call_method("draw", ()).unwrap();
+            }
+            // TODO: switch to enum
+            // LuaValue::UserData(user_data) => {
+            //     if user_data.is::<Text>() {
+            //         let text = user_data
+            //             .borrow::<Text>()
+            //             .expect("Couldn't borrow Text user data");
+            //
+            //         SENDER.with(|f| {
+            //             f.borrow_mut()
+            //                 .as_ref()
+            //                 .expect("Not currently drawing")
+            //                 .send(Message::AddDrawable(CoreShape::Text(text.0.clone())))
+            //                 .expect("Could not send shape");
+            //         })
+            //     } else {
+            //         panic!("Non-drawable passed to draw");
+            //     }
+            // }
+            _ => panic!("Non-drawable passed to draw"),
+        }
+
+        SENDER.with(|s| {
+            *s.borrow_mut() = None;
+        });
+    });
 
     Ok(())
 }
@@ -128,11 +464,91 @@ fn draw(_: &Lua, params: LuaTable) -> LuaResult<()> {
 fn libdiaphragm(lua: &Lua) -> LuaResult<LuaTable> {
     // TODO: the solver as a mutable global solves so much problem (pun not intended)
     let exports = lua.create_table()?;
+    exports.set("float", lua.create_function(float)?)?;
+
     exports.set("text", lua.create_function(text)?)?;
     exports.set("font", lua.create_function(font)?)?;
-    exports.set("float", lua.create_function(float)?)?;
 
+    exports.set("rectangle", lua.create_function(rectangle)?)?;
+
+    exports.set("constrain", lua.create_function(constrain)?)?;
     exports.set("draw", lua.create_function(draw)?)?;
 
+    // Setting up metatables
+    // ---
+
+    let float_metatable = lua
+        .create_userdata(Float(CoreFloat::Fixed(0.)))
+        .unwrap()
+        .get_metatable()
+        .unwrap();
+
+    macro_rules! float_metamethod {
+        ($method: ident, $op: ident) => {
+            float_metatable
+                .set(
+                    LuaMetaMethod::$method,
+                    lua.create_function(|_lua, (lhs, rhs): (Float, LuaValue)| {
+                        let rhs = Float::try_from(rhs).unwrap();
+                        Ok(Float(runtime_thread_do(Box::new(move |r| {
+                            r.solver_ctx().$op(&[lhs.0, rhs.0])
+                        }))))
+                    })
+                    .unwrap(),
+                )
+                .unwrap();
+        };
+    }
+
+    float_metamethod!(Add, float_add);
+    float_metamethod!(Sub, float_sub);
+    float_metamethod!(Mul, float_mul);
+
+    float_metatable
+        .set(
+            LuaMetaMethod::Div,
+            lua.create_function(|_lua, (lhs, rhs): (Float, LuaValue)| {
+                let rhs = Float::try_from(rhs).unwrap();
+                Ok(Float(runtime_thread_do(Box::new(move |r| {
+                    r.solver_ctx().float_div(lhs.0, rhs.0)
+                }))))
+            })
+            .unwrap(),
+        )
+        .unwrap();
+
+    float_metatable
+        .set(
+            LuaMetaMethod::Unm,
+            lua.create_function(|_lua, f: Float| {
+                Ok(Float(runtime_thread_do(Box::new(move |r| {
+                    r.solver_ctx().float_neg(f.0)
+                }))))
+            })
+            .unwrap(),
+        )
+        .unwrap();
+
+    // Not the operators `==`, `!=`, `<`, `<=`, `>`, and `>=` because Lua converts result to bool
+
+    let bool_metatable = lua
+        .create_userdata(Bool(CoreBool::new(VariableHandle::new(0))))
+        .unwrap()
+        .get_metatable()
+        .unwrap();
+
+    bool_metatable
+        .set(
+            LuaMetaMethod::Shl,
+            lua.create_function(|_lua, (lhs, rhs): (Bool, LuaValue)| {
+                let rhs = Bool::try_from(rhs).unwrap();
+                Ok(Bool(runtime_thread_do(Box::new(move |r| {
+                    r.solver_ctx().bool_implies(lhs.0, rhs.0)
+                }))))
+            })
+            .unwrap(),
+        )
+        .unwrap();
+
     Ok(exports)
 }