const std = @import("std");
const zm = @import("zmath");
const protocol = @import("protocol.zig");

pub const entity_id = u64;
pub const INVALID_ENTITY_ID: entity_id = 0;

pub const EntityKinds = .{
    Player,
    Monster,
    Projectile,
};

pub const Player = struct {
    id: entity_id = INVALID_ENTITY_ID,
    pos: zm.Vec,
    hp: i32,

    pub fn encode(self: Projectile, w: *std.Io.Writer) !void {
        try w.writeInt(u64, self.id, .little);
        try protocol.writeVec4(w, self.pos);
        try protocol.writeVec4(w, self.vel);
    }

    pub fn decode(r: *std.Io.Reader) !Projectile {
        return .{
            .id = try r.readInt(u64, .little),
            .pos = try protocol.readVec4(r),
            .vel = try protocol.readVec4(r),
        };
    }
};

pub const Monster = struct {
    id: entity_id = INVALID_ENTITY_ID,
    pos: zm.Vec,
    hp: i32,

    pub fn encode(self: Projectile, w: *std.Io.Writer) !void {
        try w.writeInt(u64, self.id, .little);
        try protocol.writeVec4(w, self.pos);
        try protocol.writeVec4(w, self.vel);
    }

    pub fn decode(r: *std.Io.Reader) !Projectile {
        return .{
            .id = try r.readInt(u64, .little),
            .pos = try protocol.readVec4(r),
            .vel = try protocol.readVec4(r),
        };
    }
};

pub const Projectile = struct {
    id: entity_id = INVALID_ENTITY_ID,
    pos: zm.Vec,
    vel: zm.Vec,

    pub fn update(self: *Projectile) void {
        self.pos = self.pos + self.vel;
        std.log.info("pos=({})", .{self.pos});
    }

    pub fn encode(self: Projectile, w: *std.Io.Writer) !void {
        try w.writeInt(u64, self.id, .little);
        try protocol.writeVec4(w, self.pos);
        try protocol.writeVec4(w, self.vel);
    }

    pub fn decode(r: *std.Io.Reader) !Projectile {
        return .{
            .id = try r.readInt(u64, .little),
            .pos = try protocol.readVec4(r),
            .vel = try protocol.readVec4(r),
        };
    }
};