"use strict"

// === CONSTANTS AND DATA ===

// Barbarian possible locations:
/*
FRANKS
	BRITANNIA
	GALLIA
	HISPANIA
	PANNONIA
	ITALIA

ALAMANNI
	PANNONIA
	ITALIA
	THRACIA
	MACEDONIA

GOTHS
	THRACIA
	MACEDONIA
	ASIA
	GALATIA
	SYRIA


SASSANIDS
	GALATIA
	ASIA
	SYRIA
	AEGYPTUS

NOMADS
	AFRCIA
	HISPANIA
	AEGYPTUS
	SYRIA

NOMAD STACKS in PROVINCES
	AEGYPTUS NOMADS
	AEGYPTUS SASSANIDS
	AFRICA NOMADS
	ASIA GOTHS
	ASIA SASSANIDS
	BRITANNIA FRANKS
	GALATIA GOTHS
	GALATIA SASSANIDS
	GALLIA FRANKS
	HISPANIA FRANKS
	HISPANIA NOMADS
	ITALIA ALAMANNI
	ITALIA FRANKS
	MACEDONIA ALAMANNI
	MACEDONIA GOTHS
	PANNONIA ALAMANNI
	PANNONIA FRANKS
	SYRIA GOTHS
	SYRIA NOMADS
	SYRIA SASSANIDS
	THRACIA ALAMANNI
	THRACIA GOTHS
*/


const P1 = "Red"
const P2 = "Blue"
const P3 = "Yellow"
const P4 = "Green"

const PLAYER_NAMES = [ P1, P2, P3, P4 ]

const PLAYER_INDEX = {
	[P1]: 0,
	[P2]: 1,
	[P3]: 2,
	[P4]: 3,
	"Observer": -1,
}

const NO_PLACE_GOVERNOR = -1
const OFF_MAP = -1
const AVAILABLE = -1
const UNAVAILABLE = -2

const ITALIA = 0
const AEGYPTUS = 1
const AFRICA = 2
const ASIA = 3
const BRITANNIA = 4
const GALATIA = 5
const GALLIA = 6
const HISPANIA = 7
const MACEDONIA = 8
const PANNONIA = 9
const SYRIA = 10
const THRACIA = 11
const ALAMANNI_HOMELAND = 12
const FRANKS_HOMELAND = 13
const GOTHS_HOMELAND = 14
const NOMADS_HOMELAND = 15
const SASSANIDS_HOMELAND = 16
const MARE_OCCIDENTALE = 17
const MARE_ORIENTALE = 18
const OCEANUS_ATLANTICUS = 19
const PONTUS_EUXINUS = 20

const ARMY = [
	[ 100, 101, 102, 103, 104, 105 ],
	[ 200, 201, 202, 203, 204, 205 ],
	[ 300, 301, 302, 303, 304, 305 ],
	[ 400, 401, 402, 403, 404, 405 ]
]

const REGION_NAME = [
	"Italia",
	"Aegyptus",
	"Africa",
	"Asia",
	"Britannia",
	"Galatia",
	"Gallia",
	"Hispania",
	"Macedonia",
	"Pannonia",
	"Syria",
	"Thracia",
	"Alamanni Homeland",
	"Franks Homeland",
	"Goths Homeland",
	"Nomads Homeland",
	"Sassanids Homeland",
]

const ALAMANNI = 0
const FRANKS = 1
const GOTHS = 2
const NOMADS = 3
const SASSANIDS = 4

const BARBARIAN_NAME = [
	"Alamanni",
	"Franks",
	"Goths",
	"Nomads",
	"Sassanids",
]

const ALAMANNI_UNITS = [ 0, 9 ]
const FRANKS_UNITS = [ 10, 19 ]
const GOTHS_UNITS = [ 20, 29 ]
const NOMADS_UNITS = [ 30, 39 ]
const SASSANIDS_UNITS = [ 40, 49 ]

const LEGION_UNITS = [ 50, 82 ]

const BARBARIAN_UNITS = [
	ALAMANNI_UNITS,
	FRANKS_UNITS,
	GOTHS_UNITS,
	NOMADS_UNITS,
	SASSANIDS_UNITS,
]

const BARBARIAN_HOMELAND = [
	ALAMANNI_HOMELAND,
	FRANKS_HOMELAND,
	GOTHS_HOMELAND,
	NOMADS_HOMELAND,
	SASSANIDS_HOMELAND,
]

// 12x
const CARD_M1 = [ 1, 12 ]
const CARD_S1 = [ 13, 24 ]
const CARD_P1 = [ 25, 36 ]

// 9x
const CARD_M2 = [ 37, 45 ]
const CARD_S2 = [ 46, 54 ]
const CARD_P2 = [ 55, 63 ]

// 8x
const CARD_M3 = [ 64, 71 ]
const CARD_S3 = [ 72, 79 ]
const CARD_P3 = [ 80, 87 ]

// 6x
const CARD_M4 = [ 88, 93 ]
const CARD_S4 = [ 94, 99 ]
const CARD_P4 = [ 100, 105 ]

const EVENT_PLAGUE_OF_CYPRIAN = 1
const EVENT_ARDASHIR = 2
const EVENT_PRIEST_KING = 3
const EVENT_PALMYRA_ALLIES = 4
const EVENT_SHAPUR_I = 5
const EVENT_POSTUMUS = 6
const EVENT_LUDI_SAECULARES = 7
const EVENT_CNIVA = 8
const EVENT_ZENOBIA = 9
const EVENT_BAD_AUGURIES = 10
const EVENT_RAIDING_PARTIES = 11
const EVENT_PREPARING_FOR_WAR = 12
const EVENT_INFLATION = 13
const EVENT_GOOD_AUGURIES = 14
const EVENT_DIOCLETIAN = 15

const CRISIS_TABLE_4P = [ 0, 0,
	"Ira Deorum",
	SASSANIDS,
	FRANKS,
	SASSANIDS,
	GOTHS,
	"Event",
	ALAMANNI,
	NOMADS,
	FRANKS,
	NOMADS,
	"Pax Deorum"
]

const CRISIS_TABLE_3P = [ 0, 0,
	"Ira Deorum",
	FRANKS,
	SASSANIDS,
	SASSANIDS,
	FRANKS,
	"Event",
	ALAMANNI,
	GOTHS,
	GOTHS,
	ALAMANNI,
	"Pax Deorum"
]

const CRISIS_TABLE_2P = [ 0, 0,
	"Ira Deorum",
	FRANKS,
	ALAMANNI,
	FRANKS,
	GOTHS,
	"Event",
	GOTHS,
	FRANKS,
	ALAMANNI,
	ALAMANNI,
	"Pax Deorum"
]

// ===

var game
var view

const states = {}

exports.scenarios = [ "Standard" ]

exports.roles = function (scenario, options) {
	if (options.players == 2)
		return [ P1, P2 ]
	if (options.players == 3)
		return [ P1, P2, P3 ]
	return [ P1, P2, P3, P4 ]
}

function setup_player_deck(pi) {
	return [
		CARD_M1[0] + (pi * 3) + 0,
		CARD_M1[0] + (pi * 3) + 1,
		CARD_M1[0] + (pi * 3) + 2,
		CARD_S1[0] + (pi * 3) + 0,
		CARD_S1[0] + (pi * 3) + 1,
		CARD_S1[0] + (pi * 3) + 2,
		CARD_P1[0] + (pi * 3) + 0,
		CARD_P1[0] + (pi * 3) + 1,
		CARD_P1[0] + (pi * 3) + 2,
	]
}

function setup_events() {
	let deck = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 ]
	shuffle(deck)
	// Shuffle Diocletian with last 3 cards
	array_insert(deck, 11 + random(4), 15)
	return deck
}

function setup_market_pile(cards) {
	let pile = []
	for (let c = cards[0]; c <= cards[1]; ++c)
		pile.push(c)
	return pile
}

function setup_barbarians(tribe) {
	for (let i = BARBARIAN_UNITS[tribe][0]; i <= BARBARIAN_UNITS[tribe][1]; ++i)
		game.barbarians[i] = BARBARIAN_HOMELAND[tribe]
}

function remove_barbarians(tribe) {
	for (let i = BARBARIAN_UNITS[tribe][0]; i <= BARBARIAN_UNITS[tribe][1]; ++i)
		game.barbarians[i] = OFF_MAP
}

exports.setup = function (seed, scenario, options) {
	let player_count = options.players || 4

	game = {
		seed: seed,
		log: [],
		undo: [],
		active: 0,
		state: "setup",
		first: 0,
		events: null,
		active_events: [],
		support: new Array(12).fill(1),
		mobs: 0,
		militia: 0,
		quaestor: 0,
		legions: new Array(33).fill(OFF_MAP),
		is_legion_reduced: new Array(33).fill(0),
		barbarians: new Array(50).fill(OFF_MAP),
		is_barbarian_inactive: new Array(50).fill(1),
		barbarian_leaders: [ OFF_MAP, OFF_MAP, OFF_MAP ],
		rival_emperors: [ OFF_MAP, OFF_MAP, OFF_MAP ],
		amphitheater: 0,
		basilica: 0,
		limes: 0,
		dice: [ 0, 0, 0, 0 ], // first two are crisis table dice, second two are barbarian homeland dice
		market: null,
		players: [],
	}

	game.events = setup_events()
	game.market = [
		setup_market_pile(CARD_M2),
		setup_market_pile(CARD_S2),
		setup_market_pile(CARD_P2),
		setup_market_pile(CARD_M3),
		setup_market_pile(CARD_S3),
		setup_market_pile(CARD_P3),
		setup_market_pile(CARD_M4),
		setup_market_pile(CARD_S4),
		setup_market_pile(CARD_P4),
	]

	setup_barbarians(ALAMANNI)
	setup_barbarians(FRANKS)
	setup_barbarians(GOTHS)
	setup_barbarians(NOMADS)
	setup_barbarians(SASSANIDS)

	for (let pi = 0; pi < player_count; ++pi) {
		game.players[pi] = {
			legacy: 0,
			emperor_turns: 0,
			hand: [],
			draw: setup_player_deck(pi),
			discard: [],
			generals: [ AVAILABLE, UNAVAILABLE, UNAVAILABLE, UNAVAILABLE, UNAVAILABLE, UNAVAILABLE ],
			governors: [ AVAILABLE, UNAVAILABLE, UNAVAILABLE, UNAVAILABLE, UNAVAILABLE, UNAVAILABLE ],
			capital: 0,
			castra: 0,
		}
	}

	if (player_count === 4) {
		game.support[ITALIA] = 8
	}

	if (player_count === 3) {
		game.support[ITALIA] = 6
		game.support[HISPANIA] = NO_PLACE_GOVERNOR
		game.support[AFRICA] = NO_PLACE_GOVERNOR
		game.support[AEGYPTUS] = NO_PLACE_GOVERNOR
		remove_barbarians(NOMADS)
	}

	if (player_count === 2) {
		game.support[ITALIA] = 4
		game.support[BRITANNIA] = NO_PLACE_GOVERNOR
		game.support[HISPANIA] = NO_PLACE_GOVERNOR
		game.support[AFRICA] = NO_PLACE_GOVERNOR
		game.support[AEGYPTUS] = NO_PLACE_GOVERNOR
		game.support[SYRIA] = NO_PLACE_GOVERNOR
		game.support[GALATIA] = NO_PLACE_GOVERNOR
		remove_barbarians(NOMADS)
		remove_barbarians(SASSANIDS)
	}

	game.first = game.active = random(player_count)
	log(PLAYER_NAMES[game.first] + " is First Player!")

	return save_game()
}

function load_game(state) {
	game = state
	game.active = PLAYER_INDEX[game.active]
}

function save_game() {
	game.active = PLAYER_NAMES[game.active]
	return game
}

exports.action = function (state, player, action, arg) {
	load_game(state)
	let S = states[game.state]
	if (action in S) {
		S[action](arg)
	} else {
		if (action === "undo" && game.undo && game.undo.length > 0)
			pop_undo()
		else
			throw new Error("Invalid action: " + action)
	}
	return save_game()
}

exports.view = function (state, player_name) {
	let player = PLAYER_INDEX[player_name]

	load_game(state)

	view = {
		log: game.log,
		active: PLAYER_NAMES[game.active],
		prompt: null,

		militia: game.militia,
		support: game.support,
		quaestor: game.quaestor,
		mobs: game.mobs,
		legions: game.legions,
		is_legion_reduced: game.is_legion_reduced,
		barbarians: game.barbarians,
		is_barbarian_inactive: game.is_barbarian_inactive,
		barbarian_leaders: game.barbarian_leaders,
		rival_emperors: game.rival_emperors,
		amphitheater: game.amphitheater,
		basilica: game.basilica,
		limes: game.limes,
		dice: game.dice,
		market: game.market,
		players: [],
	}

	for (let i = 0; i < game.players.length; ++i) {
		view.players[i] = {
			legacy: game.players[i].legacy,
			emperor_turns: game.players[i].emperor_turns,
			generals: game.players[i].generals,
			governors: game.players[i].governors,
			capital: game.players[i].capital,
			castra: game.players[i].castra,
		}
	}

	if (game.state === "game_over") {
		view.prompt = game.victory
	} else if (game.active !== player) {
		let inactive = states[game.state].inactive || game.state
		view.prompt = `Waiting for ${PLAYER_NAMES[game.active]} \u2014 ${inactive}...`
	} else {
		view.hand = game.players[player].hand
		view.draw = game.players[player].draw
		view.discard = game.players[player].discard

		view.actions = {}
		states[game.state].prompt()
		view.prompt = PLAYER_NAMES[game.active] + ": " + view.prompt
		if (game.undo && game.undo.length > 0)
			view.actions.undo = 1
		else
			view.actions.undo = 0
	}

	save_game()
	return view
}

// === MISC ===

function log(msg) {
	game.log.push(msg)
}

// === STATES ===

function get_governor(r) {
	for (let p = 0; p < game.players.length; ++p) {
		for (let i = 0; i < 6; ++i)
			if (game.players[p].governors[i] === r)
				return p
	}
	return -1
}

function is_neutral_province(r) {
	return (game.support[r] !== NO_PLACE_GOVERNOR) && (get_governor(r) < 0)
}

function find_legion() {
	for (let i = 0; i < 33; ++i)
		if (game.legions[i] < 0)
			return i
	return -1
}

function add_militia(r) {
	game.militia |= (1 << r)
}

function remove_militia(r) {
	game.militia &= ~(1 << r)
}

function get_support(r) {
	return game.support[r]
}

function set_support(r, level) {
	game.support[r] = level
}

states.setup = {
	prompt() {
		view.prompt = "Select a starting Province."
		for (let r = 1; r < 12; ++r)
			if (is_neutral_province(r))
				gen_action("capital", r)
	},
	capital(r) {
		let p = game.active
		game.players[p].generals[0] = r
		game.players[p].governors[0] = r
		game.players[p].capital = 1
		game.legions[find_legion()] = ARMY[p][0]
		add_militia(r)

		game.active = (game.active + 1) % game.players.length
		if (game.active === game.first)
			goto_start_turn()
	},
}

// === COMMON LIBRARY ===

function gen_action(action, argument) {
	if (!(action in view.actions))
		view.actions[action] = []
	set_add(view.actions[action], argument)
}

function clear_undo() {
	if (game.undo.length > 0)
		game.undo = []
}

function push_undo() {
	let copy = {}
	for (let k in game) {
		let v = game[k]
		if (k === "undo")
			continue
		else if (k === "log")
			v = v.length
		else if (typeof v === "object" && v !== null)
			v = object_copy(v)
		copy[k] = v
	}
	game.undo.push(copy)
}

function pop_undo() {
	let save_log = game.log
	let save_undo = game.undo
	game = save_undo.pop()
	save_log.length = game.log
	game.log = save_log
	game.undo = save_undo
}

function random(range) {
	// An MLCG using integer arithmetic with doubles.
	// https://www.ams.org/journals/mcom/1999-68-225/S0025-5718-99-00996-5/S0025-5718-99-00996-5.pdf
	// m = 2**35 − 31
	return (game.seed = game.seed * 200105 % 34359738337) % range
}

function random_bigint(range) {
	// Largest MLCG that will fit its state in a double.
	// Uses BigInt for arithmetic, so is an order of magnitude slower.
	// https://www.ams.org/journals/mcom/1999-68-225/S0025-5718-99-00996-5/S0025-5718-99-00996-5.pdf
	// m = 2**53 - 111
	return (game.seed = Number(BigInt(game.seed) * 5667072534355537n % 9007199254740881n)) % range
}

function shuffle(list) {
	// Fisher-Yates shuffle
	for (let i = list.length - 1; i > 0; --i) {
		let j = random(i + 1)
		let tmp = list[j]
		list[j] = list[i]
		list[i] = tmp
	}
}

function shuffle_bigint(list) {
	// Fisher-Yates shuffle
	for (let i = list.length - 1; i > 0; --i) {
		let j = random_bigint(i + 1)
		let tmp = list[j]
		list[j] = list[i]
		list[i] = tmp
	}
}

// Fast deep copy for objects without cycles
function object_copy(original) {
	if (Array.isArray(original)) {
		let n = original.length
		let copy = new Array(n)
		for (let i = 0; i < n; ++i) {
			let v = original[i]
			if (typeof v === "object" && v !== null)
				copy[i] = object_copy(v)
			else
				copy[i] = v
		}
		return copy
	} else {
		let copy = {}
		for (let i in original) {
			let v = original[i]
			if (typeof v === "object" && v !== null)
				copy[i] = object_copy(v)
			else
				copy[i] = v
		}
		return copy
	}
}

// Array remove and insert (faster than splice)

function array_remove(array, index) {
	let n = array.length
	for (let i = index + 1; i < n; ++i)
		array[i - 1] = array[i]
	array.length = n - 1
}

function array_insert(array, index, item) {
	for (let i = array.length; i > index; --i)
		array[i] = array[i - 1]
	array[index] = item
}

function array_remove_pair(array, index) {
	let n = array.length
	for (let i = index + 2; i < n; ++i)
		array[i - 2] = array[i]
	array.length = n - 2
}

function array_insert_pair(array, index, key, value) {
	for (let i = array.length; i > index; i -= 2) {
		array[i] = array[i-2]
		array[i+1] = array[i-1]
	}
	array[index] = key
	array[index+1] = value
}

// Set as plain sorted array

function set_clear(set) {
	set.length = 0
}

function set_has(set, item) {
	let a = 0
	let b = set.length - 1
	while (a <= b) {
		let m = (a + b) >> 1
		let x = set[m]
		if (item < x)
			b = m - 1
		else if (item > x)
			a = m + 1
		else
			return true
	}
	return false
}

function set_add(set, item) {
	let a = 0
	let b = set.length - 1
	while (a <= b) {
		let m = (a + b) >> 1
		let x = set[m]
		if (item < x)
			b = m - 1
		else if (item > x)
			a = m + 1
		else
			return
	}
	array_insert(set, a, item)
}

function set_delete(set, item) {
	let a = 0
	let b = set.length - 1
	while (a <= b) {
		let m = (a + b) >> 1
		let x = set[m]
		if (item < x)
			b = m - 1
		else if (item > x)
			a = m + 1
		else {
			array_remove(set, m)
			return
		}
	}
}

function set_toggle(set, item) {
	let a = 0
	let b = set.length - 1
	while (a <= b) {
		let m = (a + b) >> 1
		let x = set[m]
		if (item < x)
			b = m - 1
		else if (item > x)
			a = m + 1
		else {
			array_remove(set, m)
			return
		}
	}
	array_insert(set, a, item)
}

// Map as plain sorted array of key/value pairs

function map_clear(map) {
	map.length = 0
}

function map_has(map, key) {
	let a = 0
	let b = (map.length >> 1) - 1
	while (a <= b) {
		let m = (a + b) >> 1
		let x = map[m<<1]
		if (key < x)
			b = m - 1
		else if (key > x)
			a = m + 1
		else
			return true
	}
	return false
}

function map_get(map, key, missing) {
	let a = 0
	let b = (map.length >> 1) - 1
	while (a <= b) {
		let m = (a + b) >> 1
		let x = map[m<<1]
		if (key < x)
			b = m - 1
		else if (key > x)
			a = m + 1
		else
			return map[(m<<1)+1]
	}
	return missing
}

function map_set(map, key, value) {
	let a = 0
	let b = (map.length >> 1) - 1
	while (a <= b) {
		let m = (a + b) >> 1
		let x = map[m<<1]
		if (key < x)
			b = m - 1
		else if (key > x)
			a = m + 1
		else {
			map[(m<<1)+1] = value
			return
		}
	}
	array_insert_pair(map, a<<1, key, value)
}

function map_delete(map, item) {
	let a = 0
	let b = (map.length >> 1) - 1
	while (a <= b) {
		let m = (a + b) >> 1
		let x = map[m<<1]
		if (item < x)
			b = m - 1
		else if (item > x)
			a = m + 1
		else {
			array_remove_pair(map, m<<1)
			return
		}
	}
}