use eframe::egui;
use crate::ast::environment::Environment;

pub mod ast;

fn main() -> eframe::Result {
    let options = eframe::NativeOptions {
        viewport: egui::ViewportBuilder::default().with_inner_size([800.0, 600.0]),
        ..Default::default()
    };
    eframe::run_native(
        "Compiler GUI",
        options,
        Box::new(|_cc| Ok(Box::new(CompilerApp::default()))),
    )
}

struct CompilerApp {
    source_code: String,
    output_log: String,
    env: Environment,
    is_first_frame: bool,
}

impl Default for CompilerApp {
    fn default() -> Self {
        Self {
            source_code: String::new(),
            output_log: String::from("Ready to compile..."),
            env: Environment::new(),
            is_first_frame: true,
        }
    }
}

impl CompilerApp {
    fn compile(&mut self) {
        match self.env.run_script(&self.source_code) {
            Ok(result) => {
                self.output_log = format!(
                    "Execution Successful.\nResult: {}\n\nFinished at {:?}",
                    result,
                    std::time::SystemTime::now(),
                );
            }
            Err(e) => {
                self.output_log = format!("Error: {}", e);
            }
        }
    }
}

impl eframe::App for CompilerApp {
    fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
        // Bottom Panel: Output Log & Controls (Resizable)
        egui::TopBottomPanel::bottom("bottom_panel")
            .resizable(true)
            .min_height(150.0)
            .default_height(250.0)
            .show(ctx, |ui| {
                ui.add_space(5.0);

                // Compile Button (at the top of the bottom panel)
                if ui.button("Compile").clicked() {
                    self.compile();
                }

                ui.add_space(5.0);
                ui.separator();
                ui.label("Output / Logs:");

                // Log Output Area
                egui::ScrollArea::vertical()
                    .id_salt("output_log_scroll")
                    .show(ui, |ui| {
                        ui.add_sized(
                            ui.available_size(),
                            egui::TextEdit::multiline(&mut self.output_log)
                                .font(egui::TextStyle::Monospace)
                                .desired_width(f32::INFINITY)
                                .interactive(false), // Read-only
                        );
                    });
            });

        // Central Panel: Source Code Editor (Fills remaining space)
        egui::CentralPanel::default().show(ctx, |ui| {
            ui.heading("Source Code Editor");
            ui.label("Input Source:");

            let editor_id = ui.id().with("source_code_editor");

            // Handle Shift+Enter shortcut BEFORE the editor handles it
            let shortcut = egui::KeyboardShortcut::new(egui::Modifiers::SHIFT, egui::Key::Enter);
            if ui.input_mut(|i| i.consume_shortcut(&shortcut)) {
                self.compile();
            }

            // Set initial focus
            if self.is_first_frame {
                ui.ctx().memory_mut(|m| m.request_focus(editor_id));
                self.is_first_frame = false;
            }

            egui::ScrollArea::vertical()
                .id_salt("source_code_scroll")
                .show(ui, |ui| {
                    ui.add_sized(
                        ui.available_size(),
                        egui::TextEdit::multiline(&mut self.source_code)
                            .id(editor_id)
                            .font(egui::TextStyle::Monospace)
                            .desired_width(f32::INFINITY)
                            .lock_focus(true),
                    );
                });
        });
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::ast::types::Value;

    #[test]
    fn test_basic_eval() {
        let env = Environment::new();
        let result = env.run_script("(+ 1 2)").unwrap();
        if let Value::Int(i) = result {
            assert_eq!(i, 3);
        } else if let Value::Float(f) = result {
            assert_eq!(f, 3.0);
        } else {
            panic!("Expected number result");
        }
    }

    #[test]
    fn test_type_error() {
        let env = Environment::new();
        // This should fail because 'if' condition must be bool (and currently '+' returns Any/Float/Int)
        // Wait, '+' returns Any currently in my registration.
        // Let's try something that definitely fails type check.
        let result = env.run_script("(if 1 2 3)");
        assert!(result.is_err());
        assert!(result.unwrap_err().contains("Condition must be boolean"));
    }
}