// Rival dungeon masters: each is a real master (gold, imps, rooms, research - see add_rival)
// played by the brain in ai.rs; this keeps their record (side, heart, difficulty, alive) for the
// interface, the goals and the victory. A master whose heart falls is out; his ground becomes
// free. Units of a rival without a master (old savegames) still use rival_ai until he gets one.

use crate::game::*;
use crate::map::*;
use serde::{Deserialize, Serialize};

pub const RIVAL_CORE_HP: f32 = 2000.0;
// a co-op AI partner helps masters short of gold: every minute it may send some
pub const PARTNER_GIFT_EVERY: f32 = 60.0;
pub const PARTNER_GIFT_BELOW: f32 = 300.0;
pub const PARTNER_GIFT: f32 = 400.0;

#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct Rival {
    pub side: u8,        // 2 (green) or 3 (blue)
    pub core: (i32, i32), // top-left corner of the 3x3 core
    pub hp: f32,
    pub alive: bool,
    pub radius: i32, // size of the dungeon around the core
    pub grow_t: f32,
    pub spawn_t: f32,
    pub attack_t: f32,
    pub difficulty: u8, // 0 easy, 1 medium, 2 hard
    pub power: f32,     // grows with the time: level of the new creatures
    #[serde(default)]
    pub gift_t: f32, // co-op AI partner: seconds until it looks whether its allies need gold
    #[serde(default)]
    pub think_t: f32, // the brain (ai.rs): seconds until the next thought
    #[serde(default)]
    pub attacking: bool, // the attack flag is set on an enemy heart
    #[serde(default)]
    pub army0: f32, // army strength when the attack began
}

impl Rival {
    pub fn centre(&self) -> (f32, f32) {
        (self.core.0 as f32 + 1.5, self.core.1 as f32 + 1.5)
    }
}

impl Game {
    // Free game: one opponent per map up to 128 x 128 tiles, two on bigger maps; with a chance of
    // one in two one of them is the humans' gate instead of a rival master
    pub fn new_free(seed: u32, w: usize, h: usize, difficulty: u8) -> Game {
        let opponents = if w * h > 128 * 128 { 2 } else { 1 };
        let mut rng = Rng((seed ^ 0x9e37_79b9) | 1);
        for _ in 0..5 {
            rng.next();
        }
        let humans = rng.f() < 0.5;
        let rivals = if humans { opponents - 1 } else { opponents };
        let opts = GenOpts { gate: humans, ..GenOpts::default() };
        let map = Map::generate_with(seed, w, h, &opts);
        let mut g = Game::from_map(map, seed);
        g.gate_on = humans;
        if humans {
            let (cx, cy) = g.map.core;
            let (gx, gy) = g.map.gate;
            let dist = ((gx - cx).abs() + (gy - cy).abs()) as f32;
            g.wave_timer = FIRST_WAVE + ((dist - 45.0) * 1.5).clamp(0.0, 300.0);
        } else {
            g.gate_hp = 0.0;
        }
        g.guard_treasures();
        // the rival dungeons on the far side, away from the gate
        let (wi, hi) = (g.map.w as i32, g.map.h as i32);
        let x = wi - 14;
        let spots: Vec<(i32, i32)> = match (rivals, humans) {
            (1, false) => vec![(x, hi / 2)],
            (1, true) => vec![(x, if g.map.gate.1 < hi / 2 { hi * 3 / 4 } else { hi / 4 })],
            (2, _) => vec![(x, hi / 4), (x, hi * 3 / 4)],
            _ => Vec::new(),
        };
        for (k, &(rx, ry)) in spots.iter().enumerate() {
            g.add_rival(2 + k as u8, rx, ry.clamp(8, hi - 9), difficulty);
        }
        g.place_all_torches();
        g.msg("msg.welcome1", vec![]);
        g.msg("msg.welcome2", vec![]);
        g.msg(if rivals == 0 { "msg.welcome_humans" } else if humans { "msg.welcome_both" } else { "msg.welcome_rivals" }, vec![rivals.to_string()]);
        g.add_wilds(seed, true);
        g.init_research(None);
        g.init_fog();
        g.place_dwarf_caves(seed);
        g
    }

    pub fn rival_alive(&self, side: u8) -> bool {
        self.rivals.iter().any(|r| r.side == side && r.alive)
    }

    // sets up a rival master around (cx, cy): a real master (ai.rs) with his heart, a little
    // ground, a portal of his own, four imps and gold by the difficulty
    pub fn add_rival(&mut self, side: u8, cx: i32, cy: i32, difficulty: u8) {
        let core = (cx - 1, cy - 1);
        self.carve_master_area(side, core);
        // his own portal beside the dungeon (if there is room)
        let owner = Owner::of_side(side);
        let (px, py) = (core.0 + 6, core.1);
        if px + 3 < mw() as i32 - 2 && py >= 2 && py + 3 < mh() as i32 - 2 {
            for y in py..py + 3 {
                for x in px..px + 3 {
                    let t = &mut self.map.t[idx(x, y)];
                    if !matches!(t.kind, Kind::Core | Kind::Gate) {
                        t.kind = Kind::Portal;
                        t.owner = owner;
                        t.gold = 0;
                        t.reinforced = false;
                    }
                }
            }
            if !self.map.portals.contains(&(px, py)) {
                self.map.portals.push((px, py));
            }
        }
        self.rivals.push(Rival { side, core, hp: RIVAL_CORE_HP, alive: true, radius: 5, grow_t: 20.0, spawn_t: 5.0, attack_t: 0.0, difficulty, power: 0.0, gift_t: PARTNER_GIFT_EVERY, think_t: 2.0, attacking: false, army0: 0.0 });
        self.adopt_master(side, core, difficulty, true);
    }

    // the rival on `side` gets (or has) a master of his own. `fresh`: a new one with imps and gold
    pub(crate) fn adopt_master(&mut self, side: u8, core: (i32, i32), difficulty: u8, fresh: bool) {
        if self.is_master(side) {
            return;
        }
        let me = self.me_side;
        self.add_master(side, core);
        self.switch_to(side);
        self.gold = crate::ai::start_gold(difficulty);
        self.mana = 150.0;
        self.recount();
        if fresh {
            let (cx, cy) = core;
            for j in 0..4 {
                self.spawn(EK::Worker, false, cx as f32 - 0.5, cy as f32 + j as f32 * 0.7 + 0.3, 1);
            }
        }
        // the creatures of that side are his
        for e in self.ents.iter_mut().filter(|e| e.alive && !e.hero && e.side == side) {
            e.home = None;
            e.target = None;
        }
        self.switch_to(me);
    }


    pub fn update_rivals(&mut self, dt: f32) {
        let back = self.me_side;
        for k in 0..self.rivals.len() {
            if !self.rivals[k].alive {
                continue;
            }
            let side = self.rivals[k].side;
            // a rival from an older savegame or a painted map: he gets his master now
            if !self.is_master(side) {
                let (core, diff) = (self.rivals[k].core, self.rivals[k].difficulty);
                self.adopt_master(side, core, diff, false);
            }
            // his heart fell: he is out
            if self.core_hp_of(side) <= 0.0 {
                if !self.out_sides.contains(&side) {
                    self.out_sides.push(side);
                }
                self.eliminate_rival(k);
                continue;
            }
            self.rivals[k].hp = self.core_hp_of(side) / CORE_HP * RIVAL_CORE_HP;
            // a co-op partner sends gold to allied masters who run short
            if self.is_partner(side) {
                self.rivals[k].gift_t -= dt;
                if self.rivals[k].gift_t <= 0.0 {
                    self.rivals[k].gift_t = PARTNER_GIFT_EVERY;
                    self.partner_gift(side);
                }
            }
            self.switch_to(side);
            self.ai_think(k, dt);
            self.switch_to(back);
        }
    }


    // damage to the core of a rival master
    pub fn rival_core_hit(&mut self, side: u8, dmg: f32) {
        let Some(k) = self.rivals.iter().position(|r| r.side == side && r.alive) else { return };
        self.rivals[k].hp -= dmg;
        let (x, y) = self.rivals[k].centre();
        self.fx(2, x, y, 0.0, 0.0, 0.3, 0xff4040ff);
        self.sfx(Sfx::CoreHit, x, y);
        if self.rivals[k].hp <= 0.0 {
            self.eliminate_rival(k);
        }
    }

    pub(crate) fn eliminate_rival(&mut self, k: usize) {
        let side = self.rivals[k].side;
        let owner = Owner::of_side(side);
        self.rivals[k].alive = false;
        self.rivals[k].hp = 0.0;
        let (x, y) = self.rivals[k].centre();
        self.fx(1, x, y, 0.0, 0.0, 1.0, 0xffffffff);
        self.sfx(Sfx::Victory, x, y);
        let key = if self.is_partner(side) {
            "msg.partner_out"
        } else if side == 2 {
            "msg.rival1_out"
        } else if side == 3 {
            "msg.rival2_out"
        } else {
            "msg.rival3_out"
        };
        self.msg(key, vec![]);
        // its creatures scatter and vanish, its ground is free
        for e in self.ents.iter_mut() {
            if e.alive && !e.hero && e.side == side {
                e.alive = false;
            }
        }
        for t in self.map.t.iter_mut() {
            if t.owner == owner {
                if t.kind == Kind::Core {
                    t.kind = Kind::Floor;
                }
                t.owner = Owner::None;
            }
        }
    }

    // where an attacker of `side`'s enemy is heading: the core (or gate) of the target side
    fn target_core_adjacent(&self, i: usize, target: u8) -> bool {
        match target {
            1 => {
                let (x, y) = xy(i);
                DIR4.iter().any(|&(dx, dy)| self.map.get(x + dx, y + dy).map_or(false, |t| t.kind == Kind::Gate))
            }
            s => self.map.adj_core_of(i, Owner::of_side(s)),
        }
    }

    fn target_alive(&self, target: u8) -> bool {
        match target {
            1 => self.has_gate() && self.gate_hp > 0.0,
            s if self.is_master(s) => !self.is_out(s) && self.core_hp_of(s) > 0.0,
            s => self.rival_alive(s),
        }
    }

    // hit the core (or gate) of the target side
    pub fn hit_target_core(&mut self, e: &mut Ent, target: u8) {
        let dmg = e.atk();
        e.cd = st(e.kind).interval;
        match target {
            s if self.is_master(s) => {
                self.damage_master_core(s, dmg);
                let (cx, cy) = self.core_of_side(s);
                self.fx(2, (e.x + cx as f32 + 1.5) * 0.5, (e.y + cy as f32 + 1.5) * 0.5, 0.0, 0.0, 0.3, 0xff4040ff);
                self.sfx(Sfx::CoreHit, e.x, e.y);
                self.hint(6, "hint.core_attacked");
            }
            1 => {
                self.gate_hp -= dmg;
                self.gate_hit_t = self.time;
                let (gx, gy) = self.gate_center();
                self.sfx(Sfx::GateHit, gx, gy);
            }
            s => self.rival_core_hit(s, dmg),
        }
    }

    // the march of an attacker on a core; false = no target (any more)
    pub fn march_on(&mut self, e: &mut Ent, dt: f32) -> bool {
        let Some(target) = e.target else { return false };
        if !self.target_alive(target) || target == e.side() {
            e.target = None;
            return false;
        }
        let cur = e.tile();
        if e.path.is_empty() && self.target_core_adjacent(cur, target) {
            e.working = true;
            if e.cd <= 0.0 {
                self.hit_target_core(e, target);
            }
            return true;
        }
        if e.path.is_empty() && e.repath <= 0.0 {
            e.repath = 1.5;
            // attackers dig their way like heroes; the player's creatures only walk
            let goal = |i: usize| self.target_core_adjacent(i, target);
            let found = if !e.hero && self.is_master(e.side()) { self.map.search(cur, self.map.creature_cost(flies(e.kind)), goal, true) } else { self.map.search(cur, self.map.hero_cost_as(flies(e.kind)), goal, true) };
            match found {
                Some(p) => e.path = p,
                None => {
                    e.target = None;
                    return false;
                }
            }
        }
        self.step_path(e, dt);
        true
    }

    // units of a rival master: fight enemies nearby, march when sent, otherwise guard home
    // an AI seat of a co-op game: an allied master who builds his own dungeon
    pub fn is_partner(&self, side: u8) -> bool {
        self.coop && self.ai_sides.contains(&side)
    }

    // the partner gives gold to every allied master below the limit
    fn partner_gift(&mut self, side: u8) {
        let me = self.me_side;
        for s in self.master_sides() {
            if self.is_out(s) || self.gold_of(s) >= PARTNER_GIFT_BELOW {
                continue;
            }
            self.switch_to(s);
            let got = self.add_gold(PARTNER_GIFT).floor();
            if got >= 1.0 {
                self.msg("msg.gold_received", vec![(got as i32).to_string(), format!("@net.side{side}")]);
                self.sfx_ui(Sfx::Payday);
            }
        }
        self.switch_to(me);
    }

    // a co-op partner's creatures follow the attack flag of the first master still standing
    fn partner_flag(&self, side: u8) -> Option<usize> {
        if !self.is_partner(side) {
            return None;
        }
        let lead = self.master_sides().into_iter().find(|s| !self.is_out(*s))?;
        if lead == self.me_side {
            self.flag
        } else {
            self.masters.iter().find(|m| m.side == lead)?.flag
        }
    }

    pub fn rival_ai(&mut self, e: &mut Ent, dt: f32) {
        if e.think <= 0.0 {
            e.think = 0.5;
            if !matches!(e.job, Job::Attack(_)) {
                let radius = if e.target.is_some() { 6.0 } else { 8.0 };
                if let Some(id) = self.nearest_enemy(e, radius) {
                    e.job = Job::Attack(id);
                    e.path.clear();
                    e.repath = 0.0;
                }
            }
        }
        // two of three healthy creatures of a co-op partner join the attack at the allies' flag
        let assist = if e.id % 3 != 0 && e.hp > e.max_hp * 0.4 { self.partner_flag(e.side) } else { None };
        if let Job::Attack(id) = e.job {
            let (hx, hy) = e.home.unwrap_or((e.x, e.y));
            let far = e.target.is_none() && assist.is_none() && (e.x - hx).powi(2) + (e.y - hy).powi(2) > 15.0 * 15.0;
            if !far && self.attack_job(e, id, dt) {
                return;
            }
            e.job = Job::None;
            e.path.clear();
        }
        if let Some(f) = assist {
            // the flag at the humans' gate: attack the gate
            let (fx, fy) = xy(f);
            let (fx, fy) = (fx as f32 + 0.5, fy as f32 + 0.5);
            let (gx, gy) = self.gate_center();
            if e.target.is_none() && self.has_gate() && self.gate_hp > 0.0 && (fx - gx).powi(2) + (fy - gy).powi(2) <= 8.0 * 8.0 {
                e.target = Some(1);
            }
        }
        if self.march_on(e, dt) {
            return;
        }
        if let Some(f) = assist {
            let (fx, fy) = xy(f);
            let d2 = (e.x - fx as f32 - 0.5).powi(2) + (e.y - fy as f32 - 0.5).powi(2);
            if d2 > 2.5 * 2.5 && e.path.is_empty() && e.repath <= 0.0 {
                e.repath = 1.5;
                if let Some(p) = self.map.creature_path(flies(e.kind), e.tile(), f) {
                    e.path = p;
                }
            }
            self.step_path(e, dt);
            return;
        }
        // guard the own dungeon
        let (hx, hy) = e.home.unwrap_or((e.x, e.y));
        let d2 = (e.x - hx).powi(2) + (e.y - hy).powi(2);
        if e.path.is_empty() && e.repath <= 0.0 {
            e.repath = 3.0 + self.rng.f() * 3.0;
            let (tx, ty) = if d2 > 36.0 { (hx, hy) } else { (hx + self.rng.f() * 8.0 - 4.0, hy + self.rng.f() * 8.0 - 4.0) };
            if self.map.walk(tx as i32, ty as i32) {
                if let Some(p) = self.map.creature_path(flies(e.kind), e.tile(), idx(tx as i32, ty as i32)) {
                    e.path = p;
                }
            }
        }
        self.step_path(e, dt);
    }
}

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

    #[test]
    fn free_games_have_one_or_two_opponents() {
        for seed in 1..=12u32 {
            for &(w, h) in &[(64usize, 64usize), (160, 160)] {
                let g = Game::new_free(seed, w, h, 1);
                let opponents = g.rivals.len() + g.gate_on as usize;
                assert_eq!(opponents, if w * h > 128 * 128 { 2 } else { 1 }, "seed {} {}x{}", seed, w, h);
                for r in &g.rivals {
                    let (cx, cy) = (r.core.0 + 1, r.core.1 + 1);
                    assert_eq!(g.map.t[idx(cx, cy)].kind, Kind::Core);
                    assert_eq!(g.map.t[idx(cx, cy)].owner, Owner::of_side(r.side));
                }
                // the player's core is untouched
                let (px, py) = g.map.core;
                assert_eq!(g.map.t[idx(px + 1, py + 1)].owner, Owner::Player);
            }
        }
    }

    // a free game with exactly one rival master and no gate
    fn rival_game(difficulty: u8) -> Game {
        (1..200u32).map(|s| Game::new_free(s, 64, 64, difficulty)).find(|g| g.rivals.len() == 1 && !g.gate_on).unwrap()
    }

    #[test]
    fn an_ai_master_builds_its_dungeon() {
        let mut g = rival_game(2);
        let side = g.rivals[0].side;
        let owner = Owner::of_side(side);
        assert!(g.is_master(side), "a real master");
        let ground0 = g.map.t.iter().filter(|t| t.owner == owner).count();
        for _ in 0..(8 * 60 * 20) {
            g.update(0.05);
        }
        let ground = g.map.t.iter().filter(|t| t.owner == owner).count();
        assert!(ground > ground0 + 30, "its imps dig and claim: {} -> {}", ground0, ground);
        g.switch_to(side);
        let rooms: usize = g.counts.iter().sum();
        let imps = g.worker_count();
        g.switch_to(0);
        assert!(rooms >= 9, "it builds rooms ({} tiles)", rooms);
        assert!(imps >= 4, "and keeps its imps");
        assert!(g.torches.iter().any(|t| g.map.t[t.wall].owner == owner || g.map.t[t.wall].solid()), "torches");
    }

    #[test]
    fn the_fourth_master_works_too_and_is_no_dwarf() {
        let mut g = (1..200u32).map(|s| Game::new_free(s, 96, 96, 1)).find(|g| g.rivals.len() == 1 && !g.gate_on).unwrap();
        let far = |g: &Game, (x, y): (i32, i32)| {
            let d = |(a, b): (i32, i32)| (a - x).pow(2) + (b - y).pow(2);
            d(g.map.core).min(d(g.rivals[0].core))
        };
        let spot = [(14, 14), (80, 14), (14, 80), (80, 80)].into_iter().max_by_key(|&p| far(&g, p)).unwrap();
        g.add_rival(4, spot.0, spot.1, 1);
        let owner = Owner::of_side(4);
        let ground0 = g.map.t.iter().filter(|t| t.owner == owner).count();
        for _ in 0..(6 * 60 * 20) {
            g.update(0.05);
        }
        assert!(g.ents.iter().any(|e| e.alive && e.side == 4 && e.rival() && !e.dwarf()), "its units belong to a master");
        let ground = g.map.t.iter().filter(|t| t.owner == owner).count();
        assert!(ground > ground0 + 20, "the yellow master digs and claims: {} -> {}", ground0, ground);
    }

    #[test]
    fn ai_dig_marks_carry_the_masters_side() {
        let mut g = rival_game(1);
        let side = g.rivals[0].side;
        for _ in 0..(40 * 20) {
            g.update(0.05);
        }
        assert!(g.map.t.iter().any(|t| t.marked && t.mark_by == side), "the AI marks in its own colour");
        let back = crate::save::from_bytes(crate::save::to_json(&g).as_bytes()).ok().expect("loads").game;
        assert_eq!(
            back.map.t.iter().filter(|t| t.marked && t.mark_by == side).count(),
            g.map.t.iter().filter(|t| t.marked && t.mark_by == side).count(),
            "kept in the save"
        );
    }

    #[test]
    fn beating_the_rival_wins_the_free_game() {
        let mut g = rival_game(1);
        let side = g.rivals[0].side;
        g.update(0.05);
        assert!(g.ents.iter().any(|e| e.side == side && e.alive));
        g.rival_core_hit(side, RIVAL_CORE_HP + 1.0);
        assert!(!g.rivals[0].alive);
        assert!(!g.ents.iter().any(|e| e.side == side && e.alive));
        assert!(!g.map.t.iter().any(|t| t.owner == Owner::of_side(side)));
        g.update(0.05);
        assert_eq!(g.state, 1, "all opponents down: victory");
    }

    #[test]
    fn humans_attack_rival_masters_too() {
        let mut g = (1..200u32).map(|s| Game::new_free(s, 160, 160, 1)).find(|g| g.rivals.len() == 1 && g.gate_on).unwrap();
        let side = g.rivals[0].side;
        let (rx, ry) = g.rivals[0].centre();
        for k in 0..4 {
            let id = g.spawn(EK::Knight, true, rx + 6.0 + k as f32 * 0.3, ry, 4);
            if let Some(e) = g.ents.iter_mut().find(|e| e.id == id) {
                e.target = Some(side);
            }
        }
        let hp0 = g.rivals[0].hp;
        let mut fought = false;
        for _ in 0..(120 * 20) {
            g.update(0.05);
            fought |= g.rivals[0].hp < hp0 || g.ents.iter().any(|e| e.rival() && e.hp < e.max_hp);
            if fought {
                break;
            }
        }
        assert!(fought, "heroes fight the rival master");
    }

    #[test]
    fn hero_waves_march_on_the_strongest_master() {
        let mut g = (1..200u32).map(|s| Game::new_free(s, 160, 160, 1)).find(|g| g.rivals.len() == 1 && g.gate_on).unwrap();
        let side = g.rivals[0].side;
        let (rx, ry) = g.rivals[0].centre();
        let army = |g: &mut Game, side: u8, x: f32, y: f32, n: usize| {
            for k in 0..n {
                let id = g.spawn(EK::Ogre, false, x + k as f32 * 0.2, y, 6);
                if let Some(e) = g.ents.iter_mut().find(|e| e.id == id) {
                    e.side = side;
                }
            }
        };
        // the rival master is far stronger: the wave marches on him and is measured against him
        g.gold = 0.0;
        army(&mut g, side, rx, ry + 2.0, 8);
        assert_eq!(g.wave_goal(), side);
        let before = g.ents.len();
        g.spawn_wave();
        let heroes: Vec<&Ent> = g.ents[before..].iter().filter(|e| e.hero).collect();
        assert!(!heroes.is_empty());
        assert!(heroes.iter().all(|e| e.target == Some(side)), "the wave marches on the rival");
        // now the player is the strongest: the next wave comes for him
        let (cx, cy) = g.map.core;
        army(&mut g, 0, cx as f32 + 1.5, cy as f32 + 4.0, 20);
        assert_eq!(g.wave_goal(), 0);
        let before = g.ents.len();
        g.spawn_wave();
        assert!(g.ents[before..].iter().filter(|e| e.hero).all(|e| e.target.is_none()), "the wave comes for the player");
    }

    // the first mission of the co-op league, set up like an offline co-op game: player on side 0,
    // an AI partner on side 2, no server
    fn offline_league_game() -> Game {
        let doc = crate::editor::coop_campaign::coop_campaign();
        let mut g = crate::campaign::start_editor_coop_mission(&doc.missions[0], 0, 77);
        g.coop = true;
        assert!(g.start_match(&[0, 2], 0));
        g.sync_ai_sides(&[2], 1);
        g.end_match();
        g
    }

    #[test]
    fn an_offline_coop_partner_is_an_allied_ai_master() {
        let mut g = offline_league_game();
        assert!(g.netplay.is_none() && g.is_master(2), "the partner is a real master without the server");
        assert!(g.rival_alive(2) && g.is_partner(2));
        assert!(g.allied(0, 2) && g.allied(2, 0));
        // short of gold: the partner helps out within a minute
        g.gold = 0.0;
        for _ in 0..(65 * 20) {
            g.update(0.05);
        }
        assert!(g.msgs.iter().any(|m| m.key == "msg.gold_received"), "the partner sent gold");
        assert_eq!(g.state, 0);
        // the partner's creatures never fight the player's
        assert!(!g.ents.iter().any(|e| e.alive && !e.hero && e.side == 0 && e.hp < e.max_hp && matches!(e.job, Job::Attack(_))));
    }

    #[test]
    fn the_partner_follows_the_attack_flag() {
        let mut g = offline_league_game();
        for _ in 0..(90 * 20) {
            g.update(0.05);
        }
        let (rx, ry) = g.rivals.iter().find(|r| r.side == 2).unwrap().centre();
        // a flag on the partner's own ground a little away from its core
        let f = (0..g.map.t.len())
            .find(|&i| {
                let (x, y) = xy(i);
                let d2 = (x as f32 - rx).powi(2) + (y as f32 - ry).powi(2);
                g.map.t[i].owner == Owner::of_side(2) && g.map.walk(x, y) && d2 > 16.0 && d2 < 36.0
            })
            .expect("partner ground");
        g.flag = Some(f);
        let (fx, fy) = xy(f);
        let mut near = false;
        for _ in 0..(30 * 20) {
            g.update(0.05);
            near |= g.ents.iter().any(|e| e.alive && e.side == 2 && !e.hero && e.id % 3 != 0 && (e.x - fx as f32 - 0.5).powi(2) + (e.y - fy as f32 - 0.5).powi(2) < 3.0 * 3.0);
            if near {
                break;
            }
        }
        assert!(near, "partner creatures gather at the flag");
    }

    #[test]
    #[ignore]
    fn ai_master_report() {
        for d in 0..3u8 {
            let mut g = (1..200u32).map(|s| Game::new_free(s, 96, 96, d)).find(|g| g.rivals.len() == 1 && !g.gate_on).unwrap();
            let side = g.rivals[0].side;
            for m in 1..=15 {
                for _ in 0..(60 * 20) {
                    g.update(0.05);
                }
                g.switch_to(side);
                let (rooms, imps, cr, gold) = (g.counts.iter().sum::<usize>(), g.worker_count(), g.creature_count(), g.gold);
                let flag = g.flag.is_some();
                let earned = g.stats.get(crate::stats::GOLD);
                let me = g.me;
                let veins = (0..g.map.t.len()).filter(|&i| g.map.t[i].marked && g.map.t[i].vein().is_some()).count();
                let marked = g.map.t.iter().filter(|t| t.marked).count();
                let near = (0..g.map.t.len()).filter(|&i| { let (x, y) = xy(i); g.map.t[i].marked && DIR4.iter().any(|&(dx, dy)| g.map.get(x + dx, y + dy).map_or(false, |n| n.owner == me && n.walkable())) }).count();
                g.switch_to(0);
                println!("diff {} min {:2}: rooms {:3} imps {:2} creatures {:2} gold {:5.0} attacking {} | marked {} veins {} reachable {} earned {:.0} | player core {:.0}", d, m, rooms, imps, cr, gold, flag, marked, veins, near, earned, g.core_hp);
            }
        }
    }
}