use std::fmt;
use std::cmp::Ordering;

#[derive(Copy,Clone)]
pub struct Position {
    pub line: u32,
    pub column: u32,
}

impl Position {
    pub fn new( line: u32, column: u32 ) -> Self {
        Self {
            line, column,
        }
    }

    pub fn none() -> Self {
        Self {
            line: 0,
            column: 0,
        }
    }

    pub fn is_none(&self) -> bool {
        self.line == 0 || self.column == 0
    }
}

impl fmt::Debug for Position {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        if self.is_none() {
            write!(f, "none")
        } else {
            write!(f, "{}:{}", self.line, self.column )
        }
    }
}

impl PartialOrd for Position {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        let ord = self.line.partial_cmp( &other.line );
        if Some(Ordering::Equal) == ord {
            self.column.partial_cmp( &other.column )
        } else {
            ord
        }
    }
}

impl Ord for Position {
    fn cmp(&self, other: &Self) -> Ordering {
        let ord = self.line.cmp( &other.line );
        if Ordering::Equal == ord {
            self.column.cmp( &other.column )
        } else {
            ord
        }
    }
}

impl PartialEq for Position {
    fn eq(&self, other: &Self) -> bool {
        self.line == other.line && self.column == other.column
    }
}

impl Eq for Position {}

#[derive(Copy,Clone)]
pub struct Range {
    start: Position,
    end: Position,
}

impl Range {
    pub fn new( start: Position, end: Position ) -> Self {
        Self {
            start, end,
        }
    }

    pub fn include(&mut self, pos: &Position ) {
        if *pos < self.start {
            self.start = pos.clone();
        }
        if *pos > self.end {
            self.end = pos.clone();
        }
    }
}

impl fmt::Debug for Range {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "{:?}-{:?}", self.start, self.end )
    }
}