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use rand::RngExt;

use crate::sim::{cell::Cell, materials::MaterialId, sim::UpdateCtx};

trait FireCellView {
    fn get_ticks_lived(self) -> u16;
    fn set_ticks_lived(&mut self, ticks: u16) -> ();
    fn is_flammable(self) -> bool;
}

impl FireCellView for Cell {
    fn get_ticks_lived(self) -> u16 {
        self.data
    }
    fn set_ticks_lived(&mut self, ticks: u16) -> () {
        self.data = ticks;
    }
    // this could be a property of the material def, I think it's better here for now
    fn is_flammable(self) -> bool {
        [MaterialId::Wood].contains(&self.material)
    }
}

#[inline]
pub fn sim_update(ctx: &mut UpdateCtx) {
    let ticks_lived = ctx.cell.get_ticks_lived();
    // 2 seconds
    if ticks_lived > 240 {
        // kill ourselves, with a chance to turn into ash
        if ctx.rng.random_range(0.0..1.0) > 0.8 {
            // TODO ash material
            ctx.set_cell(0, 0, Cell::from_material(MaterialId::Sand));
        } else {
            ctx.set_cell(0, 0, Cell::void());
        }
        return;
    }

    // 4 times in our lifespan, try to spread in a random direction
    // since it's random, fire may die out if there's nothing in that direction
    // a 1-thick line of flammable cells has a 31% chance to die each iteration
    if ticks_lived % 60 == 0 {
        let (dx, dy) = (ctx.rng.random_range(-1..=1), ctx.rng.random_range(-1..=1));
        if let Some(target) = ctx.get_cell(dx, dy)
            && target.is_flammable()
        {
            ctx.set_cell(dx, dy, Cell::from_material(MaterialId::Fire));
        }
    }

    ctx.cell.set_ticks_lived(ticks_lived + 1);
    ctx.set_cell(0, 0, *ctx.cell);
}