// Raising walls: the master plans walls on his own empty floor (the wall tool, paid at once);
// pit imps raise them as reinforced earth. Tunnels can be closed again and doors put where they
// matter. Dragging over a planned tile again cancels the plan (the gold comes back).

use crate::game::*;
use crate::map::*;

// gold a raised wall costs
pub const WALL_COST: f32 = 50.0;
// seconds of imp work for one wall
pub const WALL_WORK: f32 = 3.0;

impl Game {
    // a tile where a wall may be planned: own plain floor without a trap, door or torch stand
    fn wall_spot(&self, i: usize) -> bool {
        let t = &self.map.t[i];
        t.kind == Kind::Floor && t.owner == self.me && !self.traps.iter().any(|tr| tr.tile == i)
    }

    // the wall tool over a rectangle: plans walls (or cancels planned ones)
    pub fn plan_walls(&mut self, x0: i32, y0: i32, x1: i32, y1: i32) {
        let (mut planned, mut cancelled, mut broke) = (0, 0, false);
        for y in y0.min(y1)..=y0.max(y1) {
            for x in x0.min(x1)..=x0.max(x1) {
                if !inb(x, y) {
                    continue;
                }
                let i = idx(x, y);
                if let Some(k) = self.wall_plans.iter().position(|p| p.0 == i && p.1 == self.me_side) {
                    self.wall_plans.swap_remove(k);
                    self.gold += WALL_COST;
                    cancelled += 1;
                    continue;
                }
                if !self.wall_spot(i) {
                    continue;
                }
                if self.gold < WALL_COST {
                    broke = true;
                    continue;
                }
                self.gold -= WALL_COST;
                self.wall_plans.push((i, self.me_side));
                planned += 1;
            }
        }
        if broke {
            self.msg("msg.no_gold", vec![]);
            self.sfx_ui(Sfx::Error);
        } else if planned + cancelled == 0 {
            self.hint(33, "hint.wall_where");
        } else {
            self.sfx_ui(Sfx::FlagSet);
        }
    }

    // a planned wall of the master being processed next to tile i (for his imps)
    pub(crate) fn planned_wall_near(&self, i: usize, me: u32) -> Option<usize> {
        if self.wall_plans.is_empty() {
            return None;
        }
        let (x, y) = xy(i);
        DIR4.iter().find_map(|&(dx, dy)| {
            if !inb(x + dx, y + dy) {
                return None;
            }
            let n = idx(x + dx, y + dy);
            let t = &self.map.t[n];
            let mine = self.wall_plans.iter().any(|p| p.0 == n && p.1 == self.me_side);
            (mine && (t.reserved == 0 || t.reserved == me)).then_some(n)
        })
    }

    // an imp works on a planned wall: true while there is more to do
    pub(crate) fn raise_wall_job(&mut self, e: &mut Ent, w: usize, dt: f32) -> bool {
        let me = e.id + 1;
        let planned = self.wall_plans.iter().any(|p| p.0 == w && p.1 == self.me_side);
        if !planned || !adj4(e.tile(), w) {
            return false;
        }
        // the ground was lost or built over: the plan is dropped, the gold comes back
        if !self.wall_spot(w) {
            self.wall_plans.retain(|p| p.0 != w);
            self.gold += WALL_COST;
            return false;
        }
        self.map.t[w].reserved = me;
        let (wx, wy) = xy(w);
        e.face = sgn(wx as f32 + 0.5 - e.x);
        e.working = true;
        e.timer += dt * self.help_speed(w);
        if e.timer < WALL_WORK {
            return true;
        }
        e.timer = 0.0;
        // whoever stands there steps aside
        let bank = DIR8.iter().map(|&(dx, dy)| (wx + dx, wy + dy)).find(|&(bx, by)| self.map.walk(bx, by) && idx(bx, by) != w);
        for o in self.ents.iter_mut() {
            if o.alive && !o.held && o.tile() == w {
                if let Some((bx, by)) = bank {
                    o.x = bx as f32 + 0.5;
                    o.y = by as f32 + 0.5;
                    o.path.clear();
                }
            }
        }
        // torch stands on the tile and wall torches facing it go
        self.torches.retain(|t| !(t.stand && t.wall == w) && !(!t.stand && {
            let (tx, ty) = xy(t.wall);
            let (dx, dy) = DIR4[t.dir % 4];
            inb(tx + dx, ty + dy) && idx(tx + dx, ty + dy) == w
        }));
        let tl = &mut self.map.t[w];
        tl.kind = Kind::Earth;
        tl.reinforced = true;
        tl.hp = 12.0;
        tl.marked = false;
        tl.reserved = 0;
        tl.bed = 0;
        tl.food = 0.0;
        self.wall_plans.retain(|p| p.0 != w);
        self.fx(8, wx as f32 + 0.5, wy as f32 + 0.5, 0.0, 0.0, 0.5, 0xff4040e0);
        self.sfx(Sfx::Reinforce, wx as f32 + 0.5, wy as f32 + 0.5);
        false
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn imps_raise_planned_walls() {
        let mut g = Game::new(4, 64, 64);
        let (cx, cy) = g.map.core;
        // own floor next to the core
        let (x, y) = (cx + 4, cy + 1);
        for (xx, yy) in [(x, y), (x - 1, y), (x + 1, y)] {
            let t = &mut g.map.t[idx(xx, yy)];
            t.kind = Kind::Floor;
            t.owner = Owner::Player;
        }
        g.gold = 1000.0;
        g.plan_walls(x, y, x, y);
        assert_eq!(g.wall_plans.len(), 1);
        assert_eq!(g.gold, 1000.0 - WALL_COST);
        // planning it again cancels (and pays back)
        g.plan_walls(x, y, x, y);
        assert!(g.wall_plans.is_empty() && g.gold == 1000.0);
        g.plan_walls(x, y, x, y);
        let mut raised = false;
        for _ in 0..(60 * 20) {
            g.update(0.05);
            if g.map.t[idx(x, y)].kind == Kind::Earth {
                raised = true;
                break;
            }
        }
        assert!(raised, "an imp raised the wall");
        assert!(g.map.t[idx(x, y)].reinforced && g.wall_plans.is_empty());
    }
}