use std::cmp::Ordering;

pub const KILO_LIMIT: u64 = 1000;
pub const MEGA_LIMIT: u64 = 1_000_000;
pub const GIGA_LIMIT: u64 = 1_000_000_000;
pub const TERA_LIMIT: u64 = 1_000_000_000_000;
pub const KIBI_LIMIT: u64 = 1024;
pub const MEBI_LIMIT: u64 = 1_048_576;
pub const GIBI_LIMIT: u64 = 1_073_741_824;
pub const TEBI_LIMIT: u64 = 1_099_511_627_776;

pub const LOG_KILO_LIMIT: f64 = 3.0;
pub const LOG_MEGA_LIMIT: f64 = 6.0;
pub const LOG_GIGA_LIMIT: f64 = 9.0;
pub const LOG_TERA_LIMIT: f64 = 12.0;

pub const LOG_KIBI_LIMIT: f64 = 10.0;
pub const LOG_MEBI_LIMIT: f64 = 20.0;
pub const LOG_GIBI_LIMIT: f64 = 30.0;
pub const LOG_TEBI_LIMIT: f64 = 40.0;

pub const LOG_KILO_LIMIT_U32: u32 = 3;
pub const LOG_MEGA_LIMIT_U32: u32 = 6;
pub const LOG_GIGA_LIMIT_U32: u32 = 9;
pub const LOG_TERA_LIMIT_U32: u32 = 12;

pub const LOG_KIBI_LIMIT_U32: u32 = 10;
pub const LOG_MEBI_LIMIT_U32: u32 = 20;
pub const LOG_GIBI_LIMIT_U32: u32 = 30;
pub const LOG_TEBI_LIMIT_U32: u32 = 40;

pub fn float_min(a: f32, b: f32) -> f32 {
    match a.partial_cmp(&b) {
        Some(x) => match x {
            Ordering::Greater => b,
            Ordering::Less => a,
            Ordering::Equal => a,
        },
        None => a,
    }
}

pub fn float_max(a: f32, b: f32) -> f32 {
    match a.partial_cmp(&b) {
        Some(x) => match x {
            Ordering::Greater => a,
            Ordering::Less => b,
            Ordering::Equal => a,
        },
        None => a,
    }
}

/// Returns a tuple containing the value and the unit.  In units of 1024.
/// This only supports up to a tebibyte.
pub fn get_exact_byte_values(bytes: u64, spacing: bool) -> (f64, String) {
    match bytes {
        b if b < KIBI_LIMIT => (
            bytes as f64,
            if spacing {
                "  B".to_string()
            } else {
                "B".to_string()
            },
        ),
        b if b < MEBI_LIMIT => (bytes as f64 / 1024.0, "KiB".to_string()),
        b if b < GIBI_LIMIT => (bytes as f64 / 1_048_576.0, "MiB".to_string()),
        b if b < TERA_LIMIT => (bytes as f64 / 1_073_741_824.0, "GiB".to_string()),
        _ => (bytes as f64 / 1_099_511_627_776.0, "TiB".to_string()),
    }
}

/// Returns a tuple containing the value and the unit.  In units of 1000.
/// This only supports up to a terabyte.  Note the "byte" unit will have a space appended to match the others.
pub fn get_simple_byte_values(bytes: u64, spacing: bool) -> (f64, String) {
    match bytes {
        b if b < KILO_LIMIT => (
            bytes as f64,
            if spacing {
                " B".to_string()
            } else {
                "B".to_string()
            },
        ),
        b if b < MEGA_LIMIT => (bytes as f64 / 1000.0, "KB".to_string()),
        b if b < GIGA_LIMIT => (bytes as f64 / 1_000_000.0, "MB".to_string()),
        b if b < TERA_LIMIT => (bytes as f64 / 1_000_000_000.0, "GB".to_string()),
        _ => (bytes as f64 / 1_000_000_000_000.0, "TB".to_string()),
    }
}

/// Gotta get partial ordering?  No problem, here's something to deal with it~
pub fn get_ordering<T: std::cmp::PartialOrd>(
    a_val: T, b_val: T, descending_order: bool,
) -> std::cmp::Ordering {
    match a_val.partial_cmp(&b_val) {
        Some(x) => match x {
            Ordering::Greater => {
                if descending_order {
                    std::cmp::Ordering::Less
                } else {
                    std::cmp::Ordering::Greater
                }
            }
            Ordering::Less => {
                if descending_order {
                    std::cmp::Ordering::Greater
                } else {
                    std::cmp::Ordering::Less
                }
            }
            Ordering::Equal => Ordering::Equal,
        },
        None => Ordering::Equal,
    }
}