// Campaign "The Broken Core": 20 missions. Each mission is a set of key data (size, rivers,
// fortresses, goals, available tools); the map generator builds the map from it.
// Texts (title, story, hints) come from the language files: camp.<key>.title / .story

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

// From which mission (0-based) on each tool is available (same order as ui::TOOLS):
// dig, hand, treasury, lair, farm, training, library, sell, flag, lightning, heal, imp,
// torture, temple, arrow tower, cannon tower, magic tower, bridge, aerie, steel
pub const TOOL_UNLOCK: [usize; 47] = [0, 0, 0, 0, 0, 2, 5, 0, 0, 3, 5, 0, 8, 12, 3, 7, 12, 1, 8, 17, 0, 7, 7, 10, 12, 12, 7, 16, 16, 7, 10, 16, 9, 13, 6, 10, 14, 17, 19, 22, 9, 13, 6, 11, 18, 0, 0];

pub struct FortDef {
    pub at: (f32, f32), // centre as a fraction of the map size
    pub size: (i32, i32),
    pub doors: &'static [usize],
    pub towers: &'static [TowerKind],
    pub tower_level: u32,
    pub guards: u32, // number of guards
    pub patrols: u32, // patrol groups of two
    pub level: u32,   // level of the knights
    pub boss: Option<(EK, u32)>,
    pub vaults: u32,
    pub vault_value: i32,
    pub shard: bool,
    pub heart: bool,
}

pub struct MissionDef {
    pub key: String,
    pub size: (usize, usize),
    pub seed: u32,
    pub gold: f32,
    pub portals: usize,
    pub treasures: usize,
    pub goals: Vec<Goal>,
    pub waves: bool,      // hero waves (from the gate)
    pub wave_limit: u32,  // 0 = endless
    pub first_wave: f32,  // seconds until the first wave
    pub gate: bool,       // free-game hero gate at the far side (wave missions)
    pub gate_defenders: bool,
    pub time_limit: f32,
    pub rivers: Vec<River>,
    pub forts: Vec<FortDef>,
    pub gift: Vec<(EK, u32)>, // creatures that join at the start
    pub rivals: Vec<(f32, f32, u8, u8)>, // rival masters: position (fraction of the map), difficulty, side (2 Mossgrim, 3 Lady Nightwell)
    pub islands: Vec<IslandDef>,
    pub caves: Vec<CaveDef>,
}

// an island in a lake of water or lava, with treasure and/or a mana spring
pub struct IslandDef {
    pub at: (f32, f32),
    pub r: i32,
    pub lava: bool,
    pub spring: bool,
    pub treasure: i32,
}

// a sealed cave: treasure and/or a lone creature in chains that joins when the cave is claimed
pub struct CaveDef {
    pub at: (f32, f32),
    pub chained: Option<(EK, u32)>,
    pub treasure: i32,
}

fn island(at: (f32, f32), lava: bool, spring: bool, treasure: i32) -> IslandDef {
    IslandDef { at, r: 2, lava, spring, treasure }
}

fn cave(at: (f32, f32), chained: Option<(EK, u32)>, treasure: i32) -> CaveDef {
    CaveDef { at, chained, treasure }
}

// carried over from the last won mission: the strongest creatures and part of the gold
#[derive(Clone, Debug, Default, Serialize, Deserialize)]
pub struct Carry {
    pub creatures: Vec<(EK, u32, f32)>, // kind, level, experience
    pub gold: f32,
    #[serde(default)]
    pub rune_free: u32, // unbuilt rune forge towers from chests
    #[serde(default)]
    pub rune_final: u32, // unbuilt or sold rune forge towers that were already given back once
}

pub const CARRY_CREATURES: usize = 5;
pub const CARRY_GOLD: f32 = 0.2;

// progress of the campaign (stored in the browser)
#[derive(Clone, Debug, Default, Serialize, Deserialize)]
pub struct Progress {
    pub done: Vec<bool>,
    pub carry: Vec<Option<Carry>>, // carry[i] = taken from mission i into mission i + 1
}

impl Progress {
    pub fn unlocked(&self, i: usize) -> bool {
        i == 0 || self.done.get(i - 1).copied().unwrap_or(false) || self.done.get(i).copied().unwrap_or(false)
    }
    pub fn is_done(&self, i: usize) -> bool {
        self.done.get(i).copied().unwrap_or(false)
    }
    pub fn set_done(&mut self, i: usize, carry: Carry) {
        let n = missions().len();
        self.done.resize(n, false);
        self.carry.resize(n, None);
        self.done[i] = true;
        self.carry[i] = Some(carry);
    }
    // what the player brings into mission i
    pub fn carry_into(&self, i: usize) -> Option<&Carry> {
        if i == 0 {
            return None;
        }
        self.carry.get(i - 1).and_then(|c| c.as_ref())
    }
}

use EK::*;
use TowerKind::{Arrow, Cannon, Magic};

fn river(lava: bool, vertical: bool, pos: f32, width: i32, bridges: u32) -> River {
    River { lava, vertical, pos, width, bridges }
}

#[allow(clippy::too_many_arguments)]
fn fort(at: (f32, f32), size: (i32, i32), doors: &'static [usize], towers: &'static [TowerKind], tower_level: u32, guards: u32, patrols: u32, level: u32, vaults: u32, vault_value: i32) -> FortDef {
    FortDef { at, size, doors, towers, tower_level, guards, patrols, level, boss: None, vaults, vault_value, shard: false, heart: false }
}

impl FortDef {
    fn shard(mut self) -> FortDef {
        self.shard = true;
        self
    }
    fn heart(mut self) -> FortDef {
        self.heart = true;
        self
    }
    fn boss(mut self, k: EK, level: u32) -> FortDef {
        self.boss = Some((k, level));
        self
    }
}

fn base(key: &str, size: (usize, usize), seed: u32, goals: Vec<Goal>) -> MissionDef {
    MissionDef {
        key: key.to_string(),
        size,
        seed,
        gold: 3000.0,
        portals: 1,
        treasures: 0,
        goals,
        waves: false,
        wave_limit: 0,
        first_wave: 300.0,
        gate: false,
        gate_defenders: false,
        time_limit: 0.0,
        rivers: Vec::new(),
        forts: Vec::new(),
        gift: Vec::new(),
        rivals: Vec::new(),
        islands: Vec::new(),
        caves: Vec::new(),
    }
}

// Converts one campaign editor mission into the same shape the campaign generator uses.
pub fn mission_def_from_doc(d: &crate::campaign_doc::MissionDoc) -> MissionDef {
    let mut out = base(&d.key, d.size, d.seed, crate::campaign_doc::parse_goals(&d.goals));
    out.gold = d.gold;
    out.portals = d.portals;
    out.treasures = d.treasures;
    out.waves = d.waves;
    out.wave_limit = d.wave_limit;
    out.first_wave = d.first_wave;
    out.gate = d.waves;
    out.gate_defenders = d.waves;
    out.time_limit = d.time_limit;
    out
}

// Rivers are at least four tiles wide: a ranged attack just reaches across.
pub fn missions() -> Vec<MissionDef> {
    let mut v = Vec::new();
    // ---- Act I: awakening
    v.push(MissionDef { gold: 2500.0, forts: vec![fort((0.74, 0.5), (15, 13), &[3], &[], 1, 4, 0, 1, 1, 1200).shard()], ..base("m01", (64, 64), 101, vec![Goal::Shards]) });
    v.push(MissionDef {
        gold: 2500.0,
        rivers: vec![river(false, true, 0.47, 4, 0)],
        forts: vec![fort((0.82, 0.5), (15, 15), &[3], &[Arrow], 1, 4, 1, 1, 1, 1500).shard()],
        ..base("m02", (72, 64), 202, vec![Goal::Shards])
    });
    v.push(MissionDef { forts: vec![fort((0.74, 0.5), (19, 17), &[3, 0], &[Arrow, Arrow], 1, 6, 2, 1, 1, 1500)], ..base("m03", (80, 72), 303, vec![Goal::KillAll]) });
    v.push(MissionDef { portals: 2, treasures: 1, waves: true, wave_limit: 4, first_wave: 270.0, gate: true, ..base("m04", (80, 72), 404, vec![Goal::Survive(4)]) });
    v.push(MissionDef {
        rivals: vec![(0.78, 0.5, 0, 2)],
        islands: vec![island((0.5, 0.2), false, false, 1200)],
        ..base("m21", (80, 80), 2121, vec![Goal::Rivals])
    });
    v.push(MissionDef {
        rivers: vec![river(false, true, 0.42, 4, 1)],
        islands: vec![island((0.45, 0.8), false, false, 1500)],
        forts: vec![fort((0.78, 0.5), (21, 21), &[3, 2], &[Arrow, Arrow, Arrow], 1, 6, 2, 2, 4, 2000)],
        ..base("m05", (88, 80), 505, vec![Goal::Loot(6000)])
    });
    v.push(MissionDef {
        caves: vec![cave((0.5, 0.22), Some((Ogre, 6)), 800), cave((0.56, 0.8), None, 1500)],
        forts: vec![fort((0.82, 0.5), (17, 17), &[3], &[Arrow, Arrow], 1, 5, 1, 2, 1, 1200).shard()],
        ..base("m22", (88, 88), 2222, vec![Goal::Freed(1), Goal::Shards])
    });
    // ---- Act II: the rivers and the other masters
    v.push(MissionDef {
        rivers: vec![river(false, true, 0.52, 5, 1)],
        forts: vec![fort((0.84, 0.5), (21, 19), &[3], &[Arrow, Cannon, Arrow, Cannon], 1, 8, 2, 2, 2, 1500).heart()],
        ..base("m06", (96, 88), 606, vec![Goal::Heart])
    });
    v.push(MissionDef {
        rivers: vec![river(true, true, 0.45, 4, 0)],
        forts: vec![fort((0.8, 0.45), (19, 19), &[3], &[Arrow, Cannon], 2, 7, 2, 2, 2, 1800).shard()],
        ..base("m07", (96, 96), 707, vec![Goal::Shards])
    });
    v.push(MissionDef {
        rivers: vec![river(false, true, 0.55, 4, 1)],
        islands: vec![island((0.4, 0.2), false, false, 2000)],
        rivals: vec![(0.8, 0.5, 1, 3)],
        ..base("m23", (104, 96), 2323, vec![Goal::Rivals])
    });
    v.push(MissionDef {
        time_limit: 900.0,
        gift: vec![(Ogre, 3), (Kobold, 3), (Kobold, 3), (Spider, 2)],
        forts: vec![
            fort((0.6, 0.27), (17, 15), &[3, 2], &[Arrow], 1, 4, 1, 2, 3, 1500),
            fort((0.78, 0.72), (17, 15), &[3, 0], &[Arrow, Cannon], 1, 4, 1, 2, 3, 1500),
        ],
        ..base("m08", (96, 96), 808, vec![Goal::Loot(8000)])
    });
    v.push(MissionDef {
        rivers: vec![river(false, false, 0.5, 4, 2)],
        forts: vec![
            fort((0.76, 0.24), (19, 17), &[3, 2], &[Arrow, Cannon], 2, 7, 2, 2, 1, 1500).shard(),
            fort((0.76, 0.76), (19, 17), &[3, 0], &[Arrow, Cannon], 2, 7, 2, 2, 1, 1500).shard(),
        ],
        ..base("m09", (112, 96), 909, vec![Goal::Shards])
    });
    v.push(MissionDef { gold: 4000.0, portals: 2, treasures: 1, waves: true, wave_limit: 6, first_wave: 240.0, gate: true, ..base("m10", (104, 96), 1010, vec![Goal::Survive(6)]) });
    v.push(MissionDef {
        islands: vec![island((0.42, 0.25), false, true, 0), island((0.6, 0.75), true, true, 800), island((0.74, 0.35), false, true, 1200)],
        forts: vec![fort((0.86, 0.6), (15, 15), &[3], &[Arrow, Cannon], 2, 6, 2, 2, 1, 1200)],
        ..base("m24", (112, 104), 2424, vec![Goal::Springs(3)])
    });
    v.push(MissionDef { forts: vec![fort((0.72, 0.5), (25, 25), &[3, 0, 2], &[Arrow, Cannon, Magic, Arrow, Cannon], 2, 8, 4, 3, 2, 2000)], ..base("m11", (112, 104), 1111, vec![Goal::KillAll]) });
    v.push(MissionDef {
        gate: true,
        waves: true,
        first_wave: 330.0,
        rivers: vec![river(false, false, 0.62, 4, 2)],
        rivals: vec![(0.8, 0.3, 1, 2)],
        ..base("m25", (120, 104), 2525, vec![Goal::Rivals])
    });
    v.push(MissionDef {
        rivers: vec![river(false, true, 0.4, 4, 1), river(true, true, 0.62, 4, 1)],
        forts: vec![fort((0.86, 0.5), (21, 25), &[3], &[Arrow, Cannon, Magic, Arrow], 2, 10, 2, 3, 2, 2000).heart().shard()],
        ..base("m12", (120, 112), 1212, vec![Goal::Heart, Goal::Shards])
    });
    // ---- Act III: the citadel and the masters
    v.push(MissionDef {
        rivers: vec![river(false, false, 0.22, 4, 1)],
        forts: vec![fort((0.75, 0.55), (27, 23), &[3, 0], &[Arrow, Cannon, Magic, Arrow, Cannon, Magic], 2, 12, 3, 3, 4, 3500)],
        ..base("m13", (120, 112), 1313, vec![Goal::Loot(13000)])
    });
    v.push(MissionDef { forts: vec![fort((0.7, 0.5), (25, 25), &[3, 1], &[Arrow, Cannon, Magic, Arrow, Cannon, Magic, Arrow, Cannon], 3, 8, 2, 3, 2, 2000)], ..base("m14", (128, 112), 1414, vec![Goal::Towers]) });
    v.push(MissionDef {
        rivers: vec![river(true, true, 0.62, 4, 1)],
        islands: vec![island((0.45, 0.78), true, true, 2500)],
        rivals: vec![(0.84, 0.5, 2, 3)],
        ..base("m26", (128, 120), 2626, vec![Goal::Rivals])
    });
    v.push(MissionDef {
        portals: 0,
        gold: 5000.0,
        gift: vec![(Ogre, 5), (Ogre, 4), (Mage, 5), (Mage, 4), (Spider, 4), (Kobold, 4), (Kobold, 4), (Mage, 3)],
        rivers: vec![river(false, true, 0.42, 4, 1)],
        forts: vec![fort((0.74, 0.5), (21, 21), &[3, 0, 2], &[Arrow, Cannon, Magic], 2, 10, 2, 3, 2, 2000)],
        ..base("m15", (128, 120), 1515, vec![Goal::KillAll])
    });
    v.push(MissionDef {
        waves: true,
        first_wave: 360.0,
        gate_defenders: true,
        rivers: vec![river(true, true, 0.55, 4, 2)],
        forts: vec![fort((0.84, 0.5), (23, 23), &[3], &[Arrow, Cannon, Magic, Arrow], 2, 10, 2, 3, 2, 2000).heart()],
        ..base("m16", (128, 128), 1616, vec![Goal::Heart])
    });
    v.push(MissionDef {
        caves: vec![cave((0.42, 0.2), Some((Chainbreaker, 4)), 1000), cave((0.45, 0.82), Some((Gargoyle, 6)), 1000), cave((0.66, 0.5), None, 3000)],
        islands: vec![island((0.62, 0.2), false, true, 0), island((0.66, 0.82), true, true, 0)],
        forts: vec![fort((0.86, 0.5), (17, 17), &[3], &[Arrow, Cannon, Magic], 3, 8, 2, 3, 1, 1500)],
        ..base("m27", (136, 128), 2727, vec![Goal::Freed(2), Goal::Springs(2)])
    });
    v.push(MissionDef {
        portals: 2,
        rivers: vec![river(false, true, 0.36, 4, 2), river(false, true, 0.56, 4, 2), river(false, false, 0.5, 4, 2)],
        forts: vec![
            fort((0.82, 0.24), (19, 17), &[3, 2], &[Arrow, Cannon, Magic], 2, 8, 2, 3, 2, 2000).shard(),
            fort((0.82, 0.76), (19, 17), &[3, 0], &[Arrow, Cannon, Magic], 2, 8, 2, 3, 2, 2000).shard(),
        ],
        ..base("m17", (136, 136), 1717, vec![Goal::Shards, Goal::Loot(6000)])
    });
    v.push(MissionDef {
        portals: 2,
        rivers: vec![river(false, true, 0.6, 4, 2)],
        islands: vec![island((0.45, 0.5), false, true, 2000)],
        rivals: vec![(0.84, 0.25, 1, 2), (0.84, 0.75, 1, 3)],
        ..base("m28", (144, 136), 2828, vec![Goal::Rivals])
    });
    v.push(MissionDef {
        portals: 2,
        rivers: vec![river(true, true, 0.5, 4, 1)],
        forts: vec![fort((0.84, 0.5), (25, 25), &[3], &[Arrow, Cannon, Magic, Arrow, Cannon, Magic], 3, 14, 3, 4, 3, 2500).heart().boss(Paladin, 5)],
        ..base("m18", (144, 144), 1818, vec![Goal::Heart])
    });
    v.push(MissionDef {
        portals: 2,
        rivers: vec![river(false, true, 0.42, 4, 2), river(true, false, 0.5, 4, 2)],
        forts: vec![
            fort((0.62, 0.22), (19, 17), &[3, 2], &[Arrow, Cannon, Magic], 3, 8, 2, 4, 1, 2500).shard(),
            fort((0.86, 0.5), (19, 19), &[3], &[Arrow, Cannon, Magic, Arrow], 3, 10, 2, 4, 1, 2500).shard(),
            fort((0.62, 0.8), (19, 17), &[3, 0], &[Arrow, Cannon, Magic], 3, 8, 2, 4, 1, 2500).shard(),
        ],
        ..base("m19", (152, 144), 1919, vec![Goal::Shards])
    });
    v.push(MissionDef {
        portals: 2,
        rivers: vec![river(true, true, 0.62, 4, 1)],
        islands: vec![island((0.42, 0.22), true, true, 2500), island((0.45, 0.78), true, true, 2500)],
        caves: vec![cave((0.5, 0.5), Some((Wyrm, 5)), 2000)],
        forts: vec![fort((0.85, 0.5), (21, 21), &[3], &[Arrow, Cannon, Magic, Magic], 3, 12, 2, 4, 2, 2500).shard()],
        ..base("m29", (152, 152), 2929, vec![Goal::Shards, Goal::Springs(2)])
    });
    v.push(MissionDef {
        portals: 3,
        gold: 5000.0,
        waves: true,
        first_wave: 420.0,
        gate_defenders: true,
        rivers: vec![river(false, true, 0.6, 6, 2)],
        forts: vec![fort((0.83, 0.5), (29, 29), &[3], &[Arrow, Cannon, Magic, Arrow, Cannon, Magic, Arrow, Magic], 3, 16, 4, 5, 4, 3000)
            .heart()
            .shard()
            .boss(Paladin, 10)],
        ..base("m20", (160, 160), 2020, vec![Goal::Heart, Goal::Shards])
    });
    v.push(MissionDef {
        portals: 3,
        gold: 6000.0,
        gate: true,
        waves: true,
        first_wave: 420.0,
        gate_defenders: true,
        rivers: vec![river(false, true, 0.45, 4, 2), river(true, false, 0.5, 4, 2)],
        islands: vec![island((0.3, 0.2), false, true, 3000)],
        rivals: vec![(0.85, 0.22, 2, 2), (0.85, 0.78, 2, 3)],
        ..base("m30", (176, 176), 3030, vec![Goal::Rivals, Goal::Heart])
    });
    v
}

// the knights of a fortress: mostly knights and archers, some priests and dwarves
fn knights(n: u32, level: u32) -> Vec<(EK, u32)> {
    let mix = [Knight, Archer, Knight, Priest, Dwarf, Archer, Knight];
    (0..n).map(|k| (mix[k as usize % mix.len()], level)).collect()
}

impl FortDef {
    fn spec(&self, w: usize, h: usize) -> FortSpec {
        let (fw, fh) = self.size;
        let x = ((self.at.0 * w as f32) as i32 - fw / 2).clamp(3, w as i32 - fw - 3);
        let y = ((self.at.1 * h as f32) as i32 - fh / 2).clamp(3, h as i32 - fh - 3);
        let mut guards = knights(self.guards, self.level);
        if let Some(b) = self.boss {
            guards.insert(0, b);
        }
        let patrols = (0..self.patrols).map(|k| vec![(if k % 2 == 0 { Knight } else { Archer }, self.level), (Knight, self.level)]).collect();
        FortSpec {
            x,
            y,
            w: fw,
            h: fh,
            doors: self.doors.to_vec(),
            towers: self.towers.to_vec(),
            tower_level: self.tower_level,
            guards,
            patrols,
            vaults: self.vaults,
            vault_value: self.vault_value,
            shard: self.shard,
            heart: self.heart,
        }
    }
}

// keeps the core area, portals, gates and fortresses (rock is carved away)
fn free_for_terrain(t: &Tile) -> bool {
    t.owner == Owner::None && !matches!(t.kind, Kind::Core | Kind::Portal | Kind::Gate | Kind::Tower | Kind::Shard)
}

// an island ringed by four tiles of water or lava
fn place_island(g: &mut Game, d: &IslandDef, w: usize, h: usize, seed: u32) {
    let (cx, cy) = ((d.at.0 * w as f32) as i32, (d.at.1 * h as f32) as i32);
    let outer = d.r + 4;
    let mut rng = Rng(seed | 1);
    for y in cy - outer..=cy + outer {
        for x in cx - outer..=cx + outer {
            if x < 2 || y < 2 || x >= w as i32 - 2 || y >= h as i32 - 2 {
                continue;
            }
            let dist = (((x - cx).pow(2) + (y - cy).pow(2)) as f32).sqrt();
            let t = &mut g.map.t[idx(x, y)];
            if !free_for_terrain(t) || dist > outer as f32 + 0.4 {
                continue;
            }
            t.gold = 0;
            t.marked = false;
            t.reinforced = false;
            t.kind = if dist <= d.r as f32 + 0.4 {
                Kind::Floor
            } else if d.lava {
                Kind::Lava
            } else {
                Kind::Water
            };
        }
    }
    if d.spring {
        g.map.t[idx(cx, cy)].kind = Kind::ManaSpring;
    }
    if d.treasure > 0 {
        let spots = [(cx - 1, cy), (cx + 1, cy), (cx, cy - 1), (cx, cy + 1)];
        let per = d.treasure / spots.len() as i32;
        for &(x, y) in &spots {
            let t = &mut g.map.t[idx(x, y)];
            t.kind = Kind::Treasury;
            t.gold = per;
            let r = rng.f();
            t.res = if r < 0.15 { 3 } else if r < 0.4 { 2 } else if r < 0.6 { 1 } else { 0 };
        }
    }
}

// a small cave sealed by earth all around, with treasure and/or a creature in chains
fn place_cave(g: &mut Game, d: &CaveDef, w: usize, h: usize) {
    let (cx, cy) = ((d.at.0 * w as f32) as i32, (d.at.1 * h as f32) as i32);
    for y in cy - 3..=cy + 3 {
        for x in cx - 3..=cx + 3 {
            if x < 2 || y < 2 || x >= w as i32 - 2 || y >= h as i32 - 2 {
                continue;
            }
            let t = &mut g.map.t[idx(x, y)];
            if !free_for_terrain(t) {
                continue;
            }
            let inside = (x - cx).abs() <= 2 && (y - cy).abs() <= 2;
            t.kind = if inside { Kind::Floor } else { Kind::Earth };
            t.gold = 0;
            t.marked = false;
            t.reinforced = false;
            t.hp = 6.0;
        }
    }
    if d.treasure > 0 {
        let spots = [(cx - 2, cy - 2), (cx + 2, cy - 2), (cx - 2, cy + 2), (cx + 2, cy + 2)];
        for &(x, y) in &spots {
            let t = &mut g.map.t[idx(x, y)];
            t.kind = Kind::Treasury;
            t.gold = d.treasure / 4;
            t.res = 2;
        }
    }
    if let Some((kind, level)) = d.chained {
        let id = g.spawn(kind, false, cx as f32 + 0.5, cy as f32 + 0.5, level);
        if let Some(e) = g.ents.iter_mut().find(|e| e.id == id) {
            e.chained = true;
        }
    }
}

// Builds the game of mission i (carry: what the last mission handed over)
pub fn start_mission(i: usize, carry: Option<&Carry>) -> Game {
    start_mission_mode(i, carry, false)
}

// A co-op campaign mission: the same mission, but without rival masters on playable sides.
pub fn start_coop_mission(i: usize, carry: Option<&Carry>) -> Game {
    start_mission_mode(i, carry, true)
}

fn start_mission_mode(i: usize, carry: Option<&Carry>, coop: bool) -> Game {
    let all = missions();
    let d = &all[i.min(all.len() - 1)];
    start_mission_def(d, i, carry, coop)
}

// A mission generated from the campaign editor file: same start pipeline, but without the
// built-in campaign table and without language-file story keys for the title.
fn start_mission_def(d: &MissionDef, i: usize, carry: Option<&Carry>, coop: bool) -> Game {
    let (w, h) = d.size;
    let opts = GenOpts { portals: Some(d.portals), treasures: Some(d.treasures), gate: d.gate, core_y: None };
    let map = Map::generate_with(d.seed, w, h, &opts);
    let mut g = Game::from_map(map, d.seed);
    g.gold = d.gold;
    for (k, r) in d.rivers.iter().enumerate() {
        let seed = d.seed.wrapping_mul(31).wrapping_add(k as u32 * 977);
        g.map.carve_river(r, seed);
    }
    let mut shards = 0;
    for f in &d.forts {
        g.build_fortress(&f.spec(w, h));
        shards += f.shard as u32;
    }
    for (k, isl) in d.islands.iter().enumerate() {
        place_island(&mut g, isl, w, h, d.seed.wrapping_add(k as u32 * 131));
    }
    for c in &d.caves {
        place_cave(&mut g, c, w, h);
    }
    if !coop {
        for &(rx, ry, diff, side) in &d.rivals {
            let x = ((rx * w as f32) as i32).clamp(10, w as i32 - 10);
            let y = ((ry * h as f32) as i32).clamp(10, h as i32 - 10);
            g.add_rival(side, x, y, diff);
        }
    }
    g.place_dwarf_caves(d.seed);
    g.add_wilds(d.seed, false);
    g.init_research(Some(i));
    g.init_fog();
    let heart = d.gate || d.forts.iter().any(|f| f.heart);
    if !heart {
        g.gate_hp = 0.0;
    }
    g.gate_on = heart;
    g.guard_treasures();
    g.place_all_torches();
    let goals: Vec<Goal> = if coop {
        d.goals.iter().filter(|&g| *g != Goal::Rivals).cloned().collect()
    } else {
        d.goals.clone()
    };
    g.mission = Some(MissionState {
        index: i,
        goals,
        tools: TOOL_UNLOCK.iter().map(|&u| u <= i).collect(),
        waves: d.waves,
        wave_limit: d.wave_limit,
        gate_defenders: d.gate_defenders,
        heart,
        time_limit: d.time_limit,
        shards,
    });
    g.wave_timer = d.first_wave;
    // new creatures stand around the core
    let (cx, cy) = g.map.core;
    let mut joiners: Vec<(EK, u32, f32)> = d.gift.iter().map(|&(k, l)| (k, l, 0.0)).collect();
    if let Some(c) = carry {
        joiners.extend(c.creatures.iter().copied());
        g.gold += c.gold;
        g.rune_free += c.rune_free;
        g.rune_final += c.rune_final;
    }
    for (k, &(kind, level, xp)) in joiners.iter().enumerate() {
        let a = k as f32 * 0.9;
        let (x, y) = (cx as f32 + 1.5 + a.cos() * 3.2, cy as f32 + 1.5 + a.sin() * 3.2);
        let id = g.spawn(kind, false, x, y, level.max(1));
        if let Some(e) = g.ents.iter_mut().find(|e| e.id == id) {
            e.xp = xp;
            e.happy = 1.0;
        }
    }
    g.msg("msg.mission_start", vec![format!("@camp.{}.title", d.key)]);
    g
}

// ------------------------------------------------------------------ editor missions

// a mission definition from editor generator settings (random maps and new painted maps)
pub fn generated_def(d: &crate::campaign_doc::MissionDoc, seed: u32) -> MissionDef {
    let mut out = mission_def_from_doc(d);
    out.seed = seed;
    let g = &d.gen;
    let mut rng = Rng(seed | 1);
    for k in 0..g.rivers.min(3) {
        out.rivers.push(river(false, k % 2 == 0, 0.3 + 0.2 * k as f32 + rng.f() * 0.08, 4, 1 + (rng.next() % 2)));
    }
    for k in 0..g.lava.min(2) {
        out.rivers.push(river(true, k % 2 == 1, 0.62 - 0.25 * k as f32, 4, 1));
    }
    let lvl = 1 + g.difficulty.min(2) as u32;
    for k in 0..g.forts.min(3) {
        let at = [(0.8, 0.5), (0.75, 0.2), (0.75, 0.8)][k as usize];
        out.forts.push(fort(at, (17, 15), &[3], &[TowerKind::Arrow, TowerKind::Arrow], lvl, 3 + 2 * lvl, lvl, lvl, 1, 1000 * lvl as i32));
    }
    for k in 0..g.rivals.min(2) {
        let (x, y) = [(0.82, 0.22), (0.82, 0.78)][k as usize];
        out.rivals.push((x, y, g.difficulty.min(2), 2 + k));
    }
    out
}

// the seed of a random map in one run of a campaign
pub fn run_map_seed(run_seed: u32, mission: usize) -> u32 {
    run_seed.wrapping_mul(2654435761).wrapping_add(mission as u32 * 40503) | 1
}

// a mission of an editor campaign: its painted map or a random map (rolled from the run's
// seed), the goals it can actually have, and its block scripts
pub fn start_editor_mission(doc: &crate::campaign_doc::MissionDoc, i: usize, run_seed: u32) -> Game {
    editor_mission_mode(doc, i, run_seed, false)
}

// the same mission for a co-op match: the other master seats (2, 3, 4) belong to the players, so
// rival masters of the map are left out (like the built-in co-op missions) and so is the Rivals goal
pub fn start_editor_coop_mission(doc: &crate::campaign_doc::MissionDoc, i: usize, run_seed: u32) -> Game {
    editor_mission_mode(doc, i, run_seed, true)
}

// editor missions that can be played in co-op: the master areas need a map of at least 72x72,
// and a goal other than beating rival masters
pub fn is_editor_coop_mission(doc: &crate::campaign_doc::MissionDoc) -> bool {
    doc.size.0 >= 72 && doc.size.1 >= 72 && crate::campaign_doc::parse_goals(&doc.goals).iter().any(|g| *g != Goal::Rivals)
}

pub fn editor_coop_indexes(doc: &crate::campaign_doc::CampaignDoc) -> Vec<usize> {
    doc.missions.iter().enumerate().filter(|(_, m)| is_editor_coop_mission(m)).map(|(i, _)| i).collect()
}

pub fn next_editor_coop_mission(doc: &crate::campaign_doc::CampaignDoc, i: usize, dir: i32) -> usize {
    let list = editor_coop_indexes(doc);
    if list.is_empty() {
        return 0;
    }
    let pos = list.iter().position(|m| *m == i).unwrap_or(0);
    list[((pos as i32 + dir).rem_euclid(list.len() as i32)) as usize]
}

// a painted map without its rival masters: their creatures go, their tiles become unowned
fn remove_rivals(g: &mut Game) {
    let sides: Vec<u8> = g.rivals.iter().map(|r| r.side).collect();
    if sides.is_empty() {
        return;
    }
    g.rivals.clear();
    g.ents.retain(|e| e.hero || !sides.contains(&e.side));
    let owners: Vec<Owner> = sides.iter().map(|&s| Owner::of_side(s)).collect();
    for t in g.map.t.iter_mut() {
        if owners.contains(&t.owner) {
            t.owner = Owner::None;
            if t.kind == Kind::Core {
                t.kind = Kind::Floor;
            }
        }
    }
    g.recount();
}

fn editor_mission_mode(doc: &crate::campaign_doc::MissionDoc, i: usize, run_seed: u32, coop: bool) -> Game {
    use crate::campaign_doc::MapDoc;
    let generated = || start_mission_def(&generated_def(doc, run_map_seed(run_seed, i)), i, None, coop);
    let mut g = match &doc.map {
        MapDoc::Fixed { game } => match load_fixed_map(game) {
            Some(mut g) => {
                if coop {
                    remove_rivals(&mut g);
                }
                g
            }
            None => generated(),
        },
        MapDoc::Random => generated(),
    };
    g.msgs.clear();
    g.state = 0;
    g.time = 0.0;
    // goals the map cannot have would be won at once: they are left out
    let shards = g.map.t.iter().filter(|t| t.kind == Kind::Shard).count() as u32;
    let heart = g.gate_hp > 0.0 && g.gate_on;
    let knight_towers = g.towers.iter().any(|t| t.hero);
    let heroes = g.ents.iter().any(|e| e.alive && e.active_hero()) || doc.waves;
    let goals: Vec<Goal> = crate::campaign_doc::parse_goals(&doc.goals)
        .into_iter()
        .filter(|goal| match goal {
            Goal::Shards => shards > 0,
            Goal::Heart => heart,
            Goal::Towers => knight_towers,
            Goal::KillAll => heroes,
            Goal::Rivals => !g.rivals.is_empty(),
            Goal::Survive(_) => doc.waves,
            _ => true,
        })
        .collect();
    g.mission = Some(MissionState {
        index: i,
        goals,
        tools: vec![true; crate::ui::TOOLS.len()],
        waves: doc.waves,
        wave_limit: doc.wave_limit,
        gate_defenders: doc.waves,
        heart,
        time_limit: doc.time_limit,
        shards,
    });
    g.wave_timer = doc.first_wave;
    g.gold = doc.gold;
    if !doc.scripts.is_empty() {
        g.script = Some(crate::mscript::ScriptState::new(doc.scripts.clone(), doc.zones.clone(), run_map_seed(run_seed, i)));
    }
    if !doc.title.is_empty() {
        g.msg("msg.mission_start_custom", vec![doc.title.clone()]);
    }
    g
}

// the map editor sets a knight fortress with its middle at (x, y); level 1..3, with a shard
pub fn editor_fort(g: &mut Game, x: i32, y: i32, level: u32, shard: bool) {
    let (w, h) = (g.map.w, g.map.h);
    let lvl = level.clamp(1, 3);
    let mut f = fort((x as f32 / w as f32, y as f32 / h as f32), (15 + 2 * lvl as i32, 13 + 2 * lvl as i32), &[3], &[TowerKind::Arrow, TowerKind::Arrow], lvl, 2 + 2 * lvl, lvl, lvl, 1, 800 * lvl as i32);
    f.shard = shard;
    g.build_fortress(&f.spec(w, h));
    g.recount();
}

// a painted map: the game state saved by the map editor
pub fn load_fixed_map(json: &str) -> Option<Game> {
    let mut g: Game = serde_json::from_str(json).ok()?;
    g.map.activate();
    g.recount();
    Some(g)
}

// missions that can be played in co-op: they fit the multiplayer master areas and do not
// depend on rival masters as their only goal
pub fn is_coop_mission(i: usize) -> bool {
    missions().get(i).map_or(false, |d| d.size.0 >= 72 && d.size.1 >= 72 && d.goals.iter().any(|&g| g != Goal::Rivals))
}

pub fn coop_mission_indexes() -> Vec<usize> {
    missions()
        .iter()
        .enumerate()
        .filter(|(_, d)| d.size.0 >= 72 && d.size.1 >= 72 && d.goals.iter().any(|&g| g != Goal::Rivals))
        .map(|(i, _)| i)
        .collect()
}

pub fn next_coop_mission(i: usize, dir: i32) -> usize {
    let list = coop_mission_indexes();
    if list.is_empty() {
        return 0;
    }
    let pos = list.iter().position(|m| *m == i).unwrap_or(0);
    list[((pos as i32 + dir).rem_euclid(list.len() as i32)) as usize]
}

// the strongest creatures and a fifth of the gold go along into the next mission
pub fn carry_from(g: &Game) -> Carry {
    let mut c: Vec<&Ent> = g.ents.iter().filter(|e| e.alive && e.creature()).collect();
    let power = |e: &Ent| e.max_hp * e.atk() / st(e.kind).interval;
    c.sort_by(|a, b| power(b).partial_cmp(&power(a)).unwrap_or(std::cmp::Ordering::Equal));
    Carry { creatures: c.iter().take(CARRY_CREATURES).map(|e| (e.kind, e.level, e.xp)).collect(), gold: (g.gold * CARRY_GOLD).floor(), rune_free: g.rune_free, rune_final: g.rune_final + g.rune_next }
}

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

    #[test]
    fn a_custom_editor_mission_can_be_started() {
        let doc = crate::campaign_doc::MissionDoc {
            key: "custom01".into(),
            title: "Custom".into(),
            size: (72, 72),
            seed: 9991,
            gold: 3500.0,
            goals: vec!["KillAll".into()],
            ..Default::default()
        };
        let def = mission_def_from_doc(&doc);
        assert_eq!(def.key, "custom01");
        assert_eq!(def.goals, vec![Goal::KillAll]);

        let g = start_mission_def(&def, 0, None, false);
        let m = g.mission.as_ref().expect("the custom mission has mission state");
        assert_eq!(m.goals, vec![Goal::KillAll]);
        assert_eq!(g.gold, 3500.0);
    }

    #[test]
    fn all_missions_build() {
        for (i, d) in missions().iter().enumerate() {
            let g = start_mission(i, None);
            let m = g.mission.as_ref().unwrap();
            let heroes = g.ents.iter().filter(|e| e.hero).count();
            println!("{} {}x{}: {} knights, {} knight towers, {} shards, goals {:?}", d.key, d.size.0, d.size.1, heroes, g.towers.iter().filter(|t| t.hero).count(), m.shards, m.goals);
            // every patrol group got its round
            let patrols = g.ents.iter().filter(|e| !e.patrol.is_empty()).count() as u32;
            assert_eq!(patrols, d.forts.iter().map(|f| f.patrols * 2).sum::<u32>(), "{}", d.key);
            // the core area is intact
            let (cx, cy) = g.map.core;
            assert_eq!(g.map.t[idx(cx + 1, cy + 1)].kind, Kind::Core, "{}", d.key);
            // goals that need something on the map have it
            for goal in &m.goals {
                match goal {
                    Goal::Shards => assert!(m.shards > 0, "{}", d.key),
                    Goal::Heart => assert!(m.heart && g.gate_hp > 0.0, "{}", d.key),
                    Goal::Towers => assert!(g.towers.iter().any(|t| t.hero), "{}", d.key),
                    Goal::KillAll => assert!(heroes > 0, "{}", d.key),
                    Goal::Loot(n) => {
                        let vaults: i32 = g.map.t.iter().filter(|t| t.kind == Kind::Treasury && t.owner == Owner::Hero).map(|t| t.gold).sum();
                        assert!(vaults as u32 >= *n, "{}: vaults hold {}", d.key, vaults);
                    }
                    Goal::Survive(_) => assert!(m.waves, "{}", d.key),
                    Goal::Rivals => assert!(!g.rivals.is_empty(), "{}", d.key),
                    Goal::Springs(n) => {
                        let springs = g.map.t.iter().filter(|t| t.kind == Kind::ManaSpring).count();
                        assert!(springs as u32 >= *n, "{}: {} springs", d.key, springs);
                    }
                    Goal::Freed(n) => {
                        let chained = g.ents.iter().filter(|e| e.alive && e.chained).count();
                        assert!(chained as u32 >= *n, "{}: {} chained", d.key, chained);
                    }
                }
            }
            // rival masters stand with an intact core
            for r in &g.rivals {
                let t = &g.map.t[idx(r.core.0 + 1, r.core.1 + 1)];
                assert!(t.kind == Kind::Core && t.owner == Owner::of_side(r.side), "{}: rival core broken", d.key);
                println!("  rival {} at {:?}", r.side, r.core);
            }
            // wave missions: the heroes can reach the core
            if m.waves {
                let (gx, gy) = g.map.gate;
                assert!(g.map.hero_path_to_core(idx(gx + 1, gy + 1)).is_some(), "{}: no hero path", d.key);
            }
            // every shard and the heart can be reached by digging and bridging from the core
            let reach = g.map.search(idx(cx + 1, cy - 2).max(0), |i| {
                let t = &g.map.t[i];
                if t.kind == Kind::Rock || t.kind == Kind::Core || t.kind == Kind::Tower {
                    None
                } else {
                    Some(1)
                }
            }, |i| g.map.t[i].kind == Kind::Shard || g.map.t[i].kind == Kind::Gate || g.map.t[i].owner == Owner::Hero, true);
            assert!(reach.is_some() || heroes == 0, "{}: fortress unreachable", d.key);
        }
    }

    #[test]
    fn missions_run_and_are_not_decided_at_once() {
        for (i, d) in missions().iter().enumerate() {
            let mut g = start_mission(i, None);
            let m = g.mission.clone().unwrap();
            assert!(!m.goals.iter().all(|&goal| g.goal_done(goal)), "{}: goals done at the start", d.key);
            let t = std::time::Instant::now();
            for _ in 0..(60 * 20) {
                g.update(0.05);
            }
            println!("{}: 60 s simulated in {} ms, state {}, core {:.0}", d.key, t.elapsed().as_millis(), g.state, g.core_hp);
            assert_eq!(g.state, 0, "{}: decided without the player", d.key);
        }
    }

    #[test]
    fn coop_missions_drop_rivals_and_are_not_decided_at_once() {
        let list = coop_mission_indexes();
        assert!(list.len() > 3, "co-op campaign needs selectable missions");
        for &i in &list {
            assert!(is_coop_mission(i), "mission {} selectable in co-op", i);
            let g = start_coop_mission(i, None);
            assert!(g.rivals.is_empty(), "mission {} must not spawn rival masters", i);
            let m = g.mission.as_ref().unwrap();
            assert!(!m.goals.iter().any(|g| *g == Goal::Rivals), "mission {} keeps the rival goal", i);
            assert!(!m.goals.is_empty(), "mission {} has a playable goal after dropping rivals", i);
            assert!(!m.goals.iter().all(|&goal| g.goal_done(goal)), "mission {} is decided at the start", i);
        }
    }

    // A simple scripted player: digs a corridor to the shard, bridges rivers on the way and
    // sends a few strong creatures along with the flag.
    fn play_to_shard(i: usize) -> (u8, f32) {
        let mut g = start_mission(i, None);
        let (cx, cy) = g.map.core;
        let shard = g.map.t.iter().position(|t| t.kind == Kind::Shard).unwrap();
        let path = g
            .map
            .search(idx(cx + 1, cy - 2), |j| {
                let t = &g.map.t[j];
                match t.kind {
                    Kind::Rock | Kind::Core | Kind::Tower => None,
                    Kind::Water | Kind::Lava => Some(3),
                    _ if t.solid() => Some(if t.reinforced { 6 } else { 2 }),
                    _ => Some(1),
                }
            }, |j| j == shard, false)
            .expect("a way to the shard");
        for &j in &path {
            if g.map.t[j].diggable() {
                g.map.t[j].marked = true;
            }
        }
        for k in [EK::Ogre, EK::Ogre, EK::Mage, EK::Ogre] {
            g.spawn(k, false, cx as f32 + 4.5, cy as f32 + 1.5, 4);
        }
        g.gold = 3000.0;
        // lair and mushroom garden at the sides of the start area
        g.build_rect(1, cx - 3, cy - 3, cx - 2, cy + 5);
        g.build_rect(2, cx + 4, cy - 3, cx + 5, cy + 5);
        g.gold = 2500.0; // as if the player had mined some gold
        let mut t = 0.0;
        while t < 1500.0 && g.state == 0 {
            for _ in 0..20 {
                g.update(0.05);
            }
            t += 1.0;
            // fallen imps are replaced
            if t as i32 % 10 == 0 && g.worker_count() < 4 {
                g.summon(cx as f32 + 1.5, cy as f32 - 1.5);
            }
            // bridges: every few seconds try to bridge the water on the path
            if t as i32 % 5 == 0 {
                for &j in &path {
                    if g.map.t[j].liquid() {
                        let (x, y) = xy(j);
                        g.build_bridges(x, y, x, y);
                    }
                }
                // the creatures follow the digging: flag at the furthest open tile of the path
                if let Some(&j) = path.iter().rev().find(|&&j| g.map.t[j].walkable()) {
                    let (x, y) = xy(j);
                    g.set_flag(x, y);
                }
            }
        }
        (g.state, t)
    }

    #[test]
    fn first_missions_can_be_won() {
        for i in [0, 1] {
            let (state, t) = play_to_shard(i);
            println!("mission {}: state {} after {} s", i + 1, state, t);
            assert_eq!(state, 1, "mission {} not won", i + 1);
        }
    }

    #[test]
    fn carry_over_takes_the_strongest() {
        let mut g = start_mission(0, None);
        for (k, l) in [(Kobold, 1), (Ogre, 5), (Spider, 2), (Mage, 4), (Kobold, 2), (Ogre, 2), (Spider, 1)] {
            g.spawn(k, false, 20.0, 20.0, l);
        }
        g.gold = 5000.0;
        let c = carry_from(&g);
        assert_eq!(c.creatures.len(), CARRY_CREATURES);
        assert_eq!(c.creatures[0].0, Ogre);
        assert_eq!(c.gold, 1000.0);
        let g2 = start_mission(1, Some(&c));
        assert_eq!(g2.ents.iter().filter(|e| e.creature()).count(), CARRY_CREATURES);
        assert_eq!(g2.gold, 2500.0 + 1000.0);
        // the tools of mission 2: bridges yes, training no
        assert!(g2.tool_allowed(17));
        assert!(!g2.tool_allowed(5));
    }
}