//! Element creation base
//!
//! The actual editor environment sits here. This especially means all tools that require low-level
//! access to the data of items currently being created. While this may be subject to change, there is
//! currently a difference between things that are being created (inside the editor) and things that
//! are part of the environment (the map).

use crate::client::config::Config;
use crate::client::input::{Binding, Input};
use crate::client::map::Map;
use crate::client::snapping::Snapper;
use crate::client::tool::*;
use crate::client::transform::Transform;
use crate::net::{Cargo, Connection};
use raylib::core::drawing::RaylibDrawHandle;
use raylib::{RaylibHandle, RaylibThread};
use std::collections::HashMap;

/// The editor containing all tools and currently the map of the stuff that has been created.
pub struct Editor {
    map: Map,
    /// HashMap that matches the ToolType with its proper activation key and of course the tool
    /// itself.
    tools: HashMap<ToolType, (Box<dyn Tool>, Binding)>,
    active: ToolType,
    config: Config,
    server: Connection<Cargo>,
}

impl Editor {
    /// Create a new editor with all tools necessary. There should be only one editor per program
    /// instance.
    pub fn new(
        rl: &mut RaylibHandle,
        rlt: &RaylibThread,
        config: Config,
        server: Connection<Cargo>,
    ) -> Self {
        let map = Map::new(rl, rlt);

        let mut tools: HashMap<ToolType, (Box<dyn Tool>, Binding)> =
            HashMap::with_capacity(ToolType::NumTools as usize);

        tools.insert(
            ToolType::RectRoomTool,
            (
                Box::new(RectRoomTool::new()),
                config.tool_activation_binds.rect_room.clone(),
            ),
        );
        tools.insert(
            ToolType::PolygonRoomTool,
            (
                Box::new(PolygonRoomTool::new()),
                config.tool_activation_binds.polygon_room.clone(),
            ),
        );
        tools.insert(
            ToolType::WallTool,
            (
                Box::new(WallTool::new()),
                config.tool_activation_binds.wall.clone(),
            ),
        );
        tools.insert(
            ToolType::IconTool,
            (
                Box::new(IconTool::new(
                    config.icon_binds.clone(),
                    map.icon_renderer(),
                )),
                config.tool_activation_binds.icon.clone(),
            ),
        );
        tools.insert(
            ToolType::DeletionTool,
            (
                Box::new(DeletionTool::new()),
                config.tool_activation_binds.deletion.clone(),
            ),
        );
        tools.insert(
            ToolType::SelectionTool,
            (
                Box::new(SelectionTool::new()),
                config.tool_activation_binds.selection.clone(),
            ),
        );

        assert_eq!(ToolType::NumTools as usize, tools.len());

        Self {
            map,
            tools,
            active: ToolType::RectRoomTool,
            config,
            server,
        }
    }

    /// Get the currently active tool. Since the every tool exists only once, it is entirely indexable
    /// by its type, which is what is actually returned.
    pub fn active(&self) -> ToolType {
        self.active
    }

    /// Set the currently active tool. Any process currently going on in a different tool will be
    /// aborted.
    pub fn set_active(&mut self, tool: ToolType) {
        if tool != self.active {
            self.tools.get_mut(&self.active).unwrap().0.deactivate();
            self.active = tool;
            self.tools
                .get_mut(&self.active)
                .expect("{:?} is not a Tool in the Editor. Maybe you forgot to register it?")
                .0
                .activate();
        }
    }

    /// Update the internal editor data where necessary and handle selecting different tools, aswell
    /// as updating the currently active tool. Should be called once every frame.
    pub fn update(
        &mut self,
        rl: &mut RaylibHandle,
        transform: &Transform,
        snapper: &Snapper,
        input: &mut Input,
    ) {
        self.poll_net();

        // Handle keybindings for tool change
        for (&tool_type, (_, activation_bind)) in self.tools.iter() {
            if input.poll_global(&activation_bind) {
                // Don't do anything if the tool does not change.
                if tool_type == self.active {
                    break;
                }

                // Activate the tool of which the key binding has been pressed.
                self.set_active(tool_type);
                break;
            }
        }

        let mouse_pos_m = transform.point_px_to_m(&rl.get_mouse_position().into());
        let snapped_mouse_pos = snapper.snap(mouse_pos_m);

        // Update the currently active tool
        let active_tool = &mut self.tools.get_mut(&self.active).unwrap().0;
        active_tool.update(&self.map, &snapped_mouse_pos);

        // Handle common keybindings many of the tools have.
        if input.poll_global(&self.config.tool_general_binds.place_single) {
            active_tool.place_single(&mut self.map, &self.server, &snapped_mouse_pos);
        }
        if input.poll_global(&self.config.tool_general_binds.finish) {
            active_tool.finish(&mut self.map, &self.server);
        }
        if input.poll_global(&self.config.tool_general_binds.abort) {
            active_tool.abort();
        }

        // Handle custom keybindings in case the tool has any.
        active_tool.handle_custom_bindings(&mut self.map, &self.server, input);
    }

    fn poll_net(&mut self) {
        while let Some(cargo) = self.server().next_packet() {
            match cargo {
                Cargo::SetRoom((id, new_room)) => {
                    if let Some(mark) = self.map.get_room_mut(id) {
                        mark.set_room(new_room);
                    } else {
                        self.map.add_room(id, new_room);
                    }
                }
                other => error!("Unknown packet received: {:?}", other),
            }
        }
    }

    /// Draw all tools and in case of the active tool also what is currently being edited by it, if
    /// that exists.
    pub fn draw_tools(&self, rld: &mut RaylibDrawHandle, transform: &Transform) {
        for (tool, _) in self.tools.values() {
            tool.draw(rld, transform);
        }
    }

    /// Get the world containing all finished elements.
    pub fn map(&self) -> &Map {
        &self.map
    }

    /// Get the server this editor is connected to. Even if the program is executed locally, this will
    /// return a server, since one must have been started locally.
    pub fn server(&self) -> &Connection<Cargo> {
        &self.server
    }

    /// Get the server this editor is connected to mutably.
    pub fn server_mut(&mut self) -> &mut Connection<Cargo> {
        &mut self.server
    }
}