use anyhow::Error as AnyError;
use std::mem;

use crate::rfactor_structs::*;

pub const MM_TELEMETRY_FILE_NAME: &str = "$rFactor2SMMP_Telemetry$";
pub const MM_SCORING_FILE_NAME: &str = "$rFactor2SMMP_Scoring$";
pub const MM_EXTENDED_FILE_NAME: &str = "$rFactor2SMMP_Extended$";
pub const MM_PITINFO_FILE_NAME: &str = "$rFactor2SMMP_PitInfo$";
pub const MM_WEATHER_FILE_NAME: &str = "$rFactor2SMMP_Weather$";
pub const MM_RULES_CONTROL_FILE_NAME: &str = "$rFactor2SMMP_RulesControl$";

pub const MAX_MAPPED_VEHICLES: usize = 128;
pub const MAX_MAPPED_IDS: usize = 512;

#[repr(C, packed(4))]
#[derive(Debug, Copy, Clone)]
pub struct rF2Telemetry {
    pub version_update_begin: u32,
    pub version_update_end: u32,
    pub bytes_update_hint: i32,

    pub num_vehicles: i32,
    pub vehicle_telemetry: [TelemInfoV01; MAX_MAPPED_VEHICLES],
}

impl rF2Telemetry {
    pub const SIZE: usize = mem::size_of::<Self>();

    pub fn vehicles(&self) -> &[TelemInfoV01] {
        &self.vehicle_telemetry[0..self.num_vehicles as usize]
    }
}

impl TryFrom<&[u8]> for rF2Telemetry {
    type Error = AnyError;

    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
        debug_assert!(value.len() == Self::SIZE);
        let fixed_size: [u8; Self::SIZE] = value.try_into().unwrap();

        Ok(unsafe { mem::transmute(fixed_size) })
    }
}

#[repr(C, packed(4))]
#[derive(Debug, Copy, Clone)]
pub struct rF2Scoring {
    pub version_update_begin: u32,
    pub version_update_end: u32,
    pub bytes_update_hint: i32,

    pub scoring_info: ScoringInfoV01,
    pub vehicles: [VehicleScoringInfoV01; MAX_MAPPED_VEHICLES],
}

impl rF2Scoring {
    pub const SIZE: usize = mem::size_of::<Self>();
}

impl TryFrom<&[u8]> for rF2Scoring {
    type Error = AnyError;

    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
        debug_assert!(value.len() == Self::SIZE);
        let fixed_size: [u8; Self::SIZE] = value.try_into().unwrap();

        Ok(unsafe { mem::transmute(fixed_size) })
    }
}