"use strict"

let states = {}
let game = null
let view = null

/* DATA */
const data = require("./data.js")
const space_name = data.space_name

function get_space_id(name) {
	return space_name.indexOf(name);
}

const S_ANDHRA = get_space_id("Andhra")
const S_BENGAL = get_space_id("Bengal")
const S_GONDWANA = get_space_id("Gondwana")
const S_GUJARAT = get_space_id("Gujarat")
const S_JAUNPUR = get_space_id("Jaunpur")
const S_KARNATAKA = get_space_id("Karnataka")
const S_MADHYADESH = get_space_id("Madhyadesh")
const S_MAHARASHTRA = get_space_id("Maharashtra")
const S_MALWA = get_space_id("Malwa")
const S_ORISSA = get_space_id("Orissa")
const S_RAJPUT_KINGDOMS = get_space_id("Rajput Kingdoms")
const S_SINDH = get_space_id("Sindh")
const S_TAMILAKAM = get_space_id("Tamilakam")
const S_DELHI = get_space_id("Delhi")
const S_MOUNTAIN_PASSES = get_space_id("Mountain Passes")
const S_PUNJAB = get_space_id("Punjab")
const S_MONGOL_INVADERS = 16
const S_DS_AVAILABLE = 17
const S_BK_AVAILABLE = 18
const S_VE_AVAILABLE = 19
const S_BK_INF_2 = 20
const S_BK_INF_4 = 21
const S_VE_INF_1 = 22
const S_VE_INF_2 = 23
const S_VE_INF_3 = 24
const S_VE_INF_4 = 25

const first_piece = data.first_piece
const last_piece = data.last_piece
const first_space = S_ANDHRA
const last_space = S_PUNJAB
const last_province = S_TAMILAKAM

const faction_name = [ "Delhi Sultanate", "Bahmani Kingdom", "Vijayanagara Empire", "Mongol Invaders" ]

exports.scenarios = [ "Standard", "Solo" ]

exports.roles = function (scenario, _options) {
	if (scenario === "Solo")
		return [ NAME_SOLO ]
	return [ NAME_DS, NAME_BK, NAME_VE ]
}

function is_current_role(role) {
	if (role === NAME_SOLO) return true
	if (role === NAME_DS) return game.current === DS
	if (role === NAME_BK) return game.current === BK
	if (role === NAME_VE) return game.current === VE
	return false
}

function load_game(state) {
	game = state
}

function save_game() {
	if (game.solo) {
		game.active = NAME_SOLO
		return game
	}
	if (game.current === DS)
		game.active = NAME_DS
	if (game.current === BK)
		game.active = NAME_BK
	if (game.current === VE)
		game.active = NAME_VE
	return game
}

exports.view = function (state, role) {
	load_game(state)

	let this_card = game.deck[0] | 0
	let deck_size = Math.max(0, game.deck.length - 1)

	view = {
		prompt: null,
		actions: null,
		log: game.log,
		current: game.current,
		vp: game.vp,
		resources: game.resources,
		bk_inf: 0,
		ve_inf: 0,
		deck: [ this_card, deck_size, game.of_gods_and_kings ],
		cylinder: game.cylinder,
		pieces: game.pieces,
		tributary: game.tributary,
		control: game.control,
		rebel: game.rebel,
	}

	if (game.result) {
		view.prompt = game.victory
	} else if (!is_current_role(role)) {
		let inactive = states[game.state].inactive
		if (!inactive) {
			if (game.vm)
				inactive = "Event"
			else
				inactive = game.state
		}
		view.prompt = `Waiting for ${faction_name[game.current]} \u2014 ${inactive}.`
	} else {
		view.actions = {}

		if (states[game.state])
			states[game.state].prompt()
		else
			view.prompt = "Unknown state: " + game.state

		if (states[game.state] && !states[game.state].disable_negotiation) {
			view.actions.ask_resources = 1
			if (game.resources[game.current] > 0)
				view.actions.transfer_resources = 1
			else
				view.actions.transfer_resources = 0
			if (game.cavalry[game.current] > 0)
				view.actions.transfer_cavalry = 1
			else
				view.actions.transfer_cavalry = 0
			if (true) // TODO: can_ask_cavalry()
				view.actions.ask_cavalry = 1
			else
				view.actions.ask_cavalry = 0
		}

		if (view.actions.undo === undefined) {
			if (game.undo && game.undo.length > 0)
				view.actions.undo = 1
			else
				view.actions.undo = 0
		}
	}

	save_game()
	return view
}

exports.action = function (state, role, action, arg) {
	load_game(state)
	let S = states[game.state]
	if (S && action in S) {
		S[action](arg)
	} else {
		if (action === "undo" && game.undo && game.undo.length > 0)
			pop_undo()
		else if (action === "ask_resources")
			action_ask_resources()
		else if (action === "ask_cavalry")
			action_ask_cavalry()
		else if (action === "transfer_resources")
			action_transfer_resources()
		else if (action === "transfer_cavalry")
			action_transfer_cavalry()
		else
			throw new Error("Invalid action: " + action)
	}
	return save_game()
}

/* SETUP */

exports.setup = function (seed, scenario, _options) {
	game = {
		seed,
		log: [],
		undo: [],
		active: null,
		current: 0,
		state: null,
		cylinder: [ ELIGIBLE, ELIGIBLE, ELIGIBLE ],
		resources: [ 12, 6, 7 ],
		vp: [ 18, 0, 0 ],
		bk_inf: 0,
		ve_inf: 0,
		tributary: 8191, // all 13 provinces
		control: [0, 0, 0],
		rebel: [null, 0, 0], // amir/raja rebel status
		pieces: Array(104).fill(AVAILABLE), // piece locations
		cavalry: [0, 0, 0],
		deck: [],
		op: {
			type: null,
			limited: null,
			free: null,
			spaces: [],
			where: null,
		},
		decree: 0
	}

	if (scenario === "Solo")
		game.solo = 1

	// TODO: setup start pieces

	// goto_card()

	game.current = DS
	game.state = "todo"

	// Setup
	setup_standard()

	setup_deck()

	goto_card()

	return save_game()
}

function setup_deck() {
	game.deck = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 ]
}

function setup_standard() {
	setup_piece(DS, DISC, 1, S_ANDHRA)
	setup_piece(DS, ELITE, 1, S_MALWA)
	setup_piece(DS, TROOPS, 4, S_DELHI)
	setup_piece(DS, TROOPS, 4, S_PUNJAB)
	setup_piece(DS, TROOPS, 3, S_MALWA)
	setup_piece(DS, TROOPS, 2, S_JAUNPUR)
	setup_piece(DS, TROOPS, 2, S_MADHYADESH)
	setup_piece(DS, TROOPS, 2, S_MOUNTAIN_PASSES)
	setup_piece(DS, TROOPS, 1, S_ANDHRA)
	setup_piece(DS, TROOPS, 1, S_GUJARAT)
	setup_piece(DS, TROOPS, 1, S_RAJPUT_KINGDOMS)
	setup_piece(DS, TROOPS, 1, S_SINDH)
	setup_piece(DS, TROOPS, 1, S_TAMILAKAM)

	setup_piece(BK, ELITE, 1, S_GONDWANA)
	setup_piece(BK, ELITE, 1, S_GUJARAT)
	setup_piece(BK, ELITE, 2, S_MADHYADESH)
	setup_piece(BK, ELITE, 4, S_MAHARASHTRA)
	setup_piece(BK, ELITE, 2, S_BK_INF_2)
	setup_piece(BK, ELITE, 2, S_BK_INF_4)

	setup_piece(VE, ELITE, 1, S_TAMILAKAM)
	setup_piece(VE, ELITE, 2, S_ANDHRA)
	setup_piece(VE, ELITE, 3, S_KARNATAKA)
	setup_piece(VE, ELITE, 2, S_VE_INF_1)
	setup_piece(VE, ELITE, 2, S_VE_INF_2)
	setup_piece(VE, ELITE, 2, S_VE_INF_3)
	setup_piece(VE, ELITE, 2, S_VE_INF_4)
}

function setup_piece(faction, type, count, where) {
	for (let p = first_piece[faction][type]; count > 0; ++p) {
		if (piece_space(p) < 0) {
			set_piece_space(p, where)
			--count
		}
	}
}


// === SEQUENCE OF PLAY ===

function this_card() {
	return game.deck[0]
}

function goto_card() {
	log_h1("C" + this_card())
	if (this_card() === "todo")
		console.log("todo")
	else
		resume_event_card()
}

function resume_event_card() {
	clear_undo()
	if (game.cylinder.includes(ELIGIBLE))
		goto_eligible()
	else
		end_card()

}

function end_card() {
	clear_undo()

	adjust_eligibility(DS)
	adjust_eligibility(BK)
	adjust_eligibility(VE)

	array_remove(game.deck, 0)
	goto_card()
}

function goto_eligible() {
	game.current = next_eligible_faction()
	if (game.current < 0) {
		end_card()
	} else {
		game.state = "eligible"
		game.op = {
			limited: 0,
			free: 0,
			spaces: [],
			where: -1,
			pass: 1
		}
	}
}

function is_eligible(faction) {
	return game.cylinder[faction] === ELIGIBLE
}

function did_option(e) {
	return (
		game.cylinder[DS] === e ||
		game.cylinder[BK] === e ||
		game.cylinder[VE] === e
	)
}

function next_eligible_faction() {
	let order = data.card_order[this_card()]
	for (let faction of order)
		if (is_eligible(faction))
			return faction
	return -1
}

function adjust_eligibility(faction) {
	if (game.cylinder[faction] === INELIGIBLE || game.cylinder[faction] === SOP_PASS || game.cylinder[faction] === SOP_LIMITED_COMMAND)
		game.cylinder[faction] = ELIGIBLE
	else if (game.cylinder[faction] !== ELIGIBLE)
		game.cylinder[faction] = INELIGIBLE
}

function goto_pass() {
	push_undo()

	game.op = 0
	game.sa = 0

	game.cylinder[game.current] = SOP_PASS
	log_h2(faction_name[game.current] + " - Pass")
	if (game.current === DS) {
		log_resources(game.current, 3)
		add_resources(game.current, 3)
	} else {
		log_resources(game.current, 1)
		add_resources(game.current, 1)
	}
	resume_event_card()
}

function goto_build() {
	init_command("Build")
	game.state = "build"
}

function goto_conscript() {
	init_command("Conscript")
	game.state = "conscript"
 }

 function goto_conscript_space() {
	push_summary()

	if (conscript_count() === 1) {
		let p = find_piece(AVAILABLE, game.current, TROOPS)
		log_summary_place(p)
		place_piece(p, game.op.where)
		end_conscript_space()
	} else {
		game.op.count = 0
		game.state = "conscript_space"
	}
 }

 function end_conscript_space() {
	log_space(game.op.where, "Conscript")
	pop_summary()
	game.state = "conscript"
 }

 function goto_rally() {
	init_command("Rally")
	game.state = "rally"
 }

 function goto_rally_space() {
	push_summary()

	if (rally_count() === 1) {
		let p = find_piece(AVAILABLE, game.current, ELITE)
		log_summary_place(p)
		place_piece(p, game.op.where)
		end_rally_space()
	} else {
		game.op.count = 0
		game.state = "rally_space"
	}
 }

 function end_rally_space() {
	log_space(game.op.where, "Rally")
	pop_summary()
	game.state = "rally"
 }

function goto_rebel() {
	init_command("Rebel")
	game.state = "rebel"
}

/* STATES */

states.eligible = {
	disable_negotiation: true,
	inactive: "Eligible Faction",
	prompt() {
		if (did_option(SOP_COMMAND_DECREE)) {
			view.prompt = `${data.card_title[this_card()]}: Event or Command.`
			view.actions.event_command = 1
		} else if (did_option(SOP_EVENT_OR_COMMAND)) {
			view.prompt = `${data.card_title[this_card()]}: Command & Decree.`
			view.actions.command_decree = 1
		} else {
			view.prompt = `${data.card_title[this_card()]}: Event or Command & Decree.`
			view.actions.command_decree = 1
			view.actions.event_command = 1
		}
		view.actions.lim_command = 1
		view.actions.pass = 1
		view.actions.undo = 0
	},
	pass: goto_pass,
	command_decree() {
		push_undo()
		game.cylinder[game.current] = SOP_COMMAND_DECREE
		game.decree = 1
		game.state = "command_decree"
	},
	event_command() {
		push_undo()
		game.cylinder[game.current] = SOP_EVENT_OR_COMMAND
		game.state = "event_command"
	},
	lim_command() {
		push_undo()
		game.cylinder[game.current] = SOP_LIMITED_COMMAND
		game.op.limited = 1
		game.state = "lim_command"
	},
}

states.command_decree = {
	inactive: "Command & Decree",
	prompt() {
		view.prompt = "Select a Command and a Decree!"
		gen_any_command()
		if (game.decree === 1)
			gen_any_decree()
	},
	build: goto_build,
	conscript: goto_conscript,
	rally: goto_rally,
	rebel: goto_rebel,
}

states.event_command = {
	inactive: "Event or Command",
	prompt() {
		view.prompt = "Select the card Event or a Command!"
		gen_any_command()
	},
	conscript: goto_conscript,
	rally: goto_rally,
	rebel: goto_rebel,
}

states.lim_command = {
	inactive: "Limited command",
	prompt() {
		view.prompt = "Select a limited Command!"
		gen_any_command()
	},
	conscript: goto_conscript,
	rally: goto_rally,
	rebel: goto_rebel,
}

states.build = {
	prompt() {
		if (game.current === BK)
			view.prompt = "Build: Select a Province with an Amir"
		else if (game.current === VE)
			view.prompt = "Build: Select a Province with a Raja"

		if (can_build()) {
			for (let s = first_space; s <= last_space; ++s) {
				if (can_build_in_space(s))
					gen_action_space(s)
			}
		}
	},
	space(s) {
		push_undo()
		push_summary()
		let p = find_piece(AVAILABLE, game.current, DISC)
		log_summary_place(p)
		place_piece(p, s)
		log_space(s, "Build")
		pop_summary()
		game.decree = 0
		game.state = "command_decree"
	}

}

states.conscript = {
	prompt() {
		view.prompt = "Conscript: Select Tributaries, Qasbah or Dehli to place troops."

		if (can_select_cmd_space(1) && can_conscript()) {
			for (let s = first_space; s <= last_space; ++s) {
				if (!is_selected_cmd_space(s) && can_conscript_in_space(s))
					gen_action_space(s)
			}
		}

		view.actions.end_conscript = prompt_end_cmd(1)
	},
	space(s) {
		push_undo()
		select_cmd_space(s, 1)
		goto_conscript_space()
	},
	end_conscript: end_command,
}

states.conscript_space = {
	prompt() {
		view.prompt = `Conscript: Place up to ${conscript_count()} Troops.`
		view.where = game.op.where
		view.actions.next = 1

		gen_place_piece(DS, TROOPS)
	},
	piece(p) {
		log_summary_place(p)
		place_piece(p, game.op.where)
		if (++game.op.count >= conscript_count())
			end_conscript_space()
	},
	next() {
		end_conscript_space()
	}
}

states.rally = {
	prompt() {
		if (game.current === BK)
			view.prompt = "Rally: Select Maharashtra or a Province with your presence"
		else if (game.current === VE)
			view.prompt = "Rally: Select Karnataka or a Province with your presence"

		if (can_select_cmd_space(1) && can_rally()) {
			for (let s = first_space; s <= last_space; ++s) {
				if (!is_selected_cmd_space(s) && can_rally_in_space(s))
					gen_action_space(s)
			}
		}

		view.actions.end_rally = prompt_end_cmd(1)
	},
	space(s) {
		push_undo()
		select_cmd_space(s, 1)
		goto_rally_space()
	},
	end_rally: end_command,
}

states.rally_space = {
	prompt() {
		view.prompt = `Rally: Place up to ${rally_count()} ${PIECE_FACTION_TYPE_NAME[game.current][ELITE]}`
		view.where = game.op.where
		view.actions.next = 1

		gen_place_piece(game.current, ELITE)
	},
	piece(p) {
		log_summary_place(p)
		place_piece(p, game.op.where)
		if (++game.op.count >= rally_count())
			end_rally_space()
	},
	next() {
		end_rally_space()
	}
}

states.rebel = {
	prompt() {
		view.prompt = "Rebel: Select a Province where you are in majority."

		if (can_select_cmd_space(1)) {
			for (let s = first_space; s <= last_space; ++s) {
				if (!is_selected_cmd_space(s) && can_rebel_in_space(s))
					gen_action_space(s)
			}
		}

		view.actions.end_rebel = prompt_end_cmd(1)
	},
	space(s) {
		push_undo()
		select_cmd_space(s, 1)
		remove_tributary(s)
		to_rebel_space(s, game.current)
		log_space(s, "Rebel")
	},
	end_rebel: end_command,

}

/* COMMANDS */

function init_command(type) {
	push_undo()
	if (game.op.limited)
		log_h2(faction_name[game.current] + " - Limited " + type)
	else
		log_h2(faction_name[game.current] + " - " + type)
	game.op.type = type
}

function gen_any_command() {
	if (game.current === DS) {
		view.actions.conscript = can_conscript() ? 1 : 0
	} else if (game.current === BK || game.current === VE) {
		view.actions.rally = can_rally() ? 1 : 0
		view.actions.rebel = can_rebel() ? 1 : 0
	}
}

function can_select_cmd_space(cost) {
	if (!game.op.free && game.resources[game.current] < cost)
		return false
	if (game.op.limited)
		return game.op.spaces.length === 0
	return true
}

function select_cmd_space(s, cost) {
	set_add(game.op.spaces, s)
	if (!game.op.free)
		game.resources[game.current] -= cost
	game.op.where = s
}

function can_conscript() {
	return has_piece(AVAILABLE, DS, TROOPS)
}

function can_conscript_in_space(s) {
	if (s === S_DELHI || has_piece(s, DS, DISC) || is_tributary(s))
		return true
}

function conscript_count() {
	if (game.op.where === S_DELHI)
		return 5
	if (has_piece(game.op.where, DS, DISC)) {
		return 2
	}
	return 1
}

function can_rally() {
	return has_piece(AVAILABLE, game.current, ELITE)
}

function can_rally_in_space(s) {
	if (game.current === BK) {
		return (s === S_MAHARASHTRA || has_piece(s, BK, ELITE) || has_piece(s, BK, DISC))
	} else if (game.current === VE) {
		return (s === S_KARNATAKA || has_piece(s, VE, ELITE) || has_piece(s, VE, DISC))
	}
}

function rally_count() {
	// TODO : Add rally with control + 1
	let count = 1
	if (game.current === BK) {
		count += (game.op.where === S_MAHARASHTRA ? 1 : 0)
	} else if (game.current === VE) {
		count += (game.op.where === S_KARNATAKA ? 1 : 0)
		count += (has_piece(game.op.where, VE, DISC) ? 1 : 0)
	}
	return count
}

function can_rebel() {
	// todo: implement dynasty logic
	for (let s = first_space; s <= last_space; ++s) {
		if (can_rebel_in_space(s))
			return true
	}
	return false
}

function can_rebel_in_space(s) {
	if (is_tributary(s) && has_majority(s) === game.current)
		return true
	return false
}

function prompt_end_cmd(cost) {
	if (!view.actions.space) {
		if (game.op.limited && game.op.spaces && game.op.spaces.length > 0)
			view.prompt = game.op.type + ": Done."
		else if (!game.op.free && game.resources[game.current] < cost)
			view.prompt = game.op.type + ": No resources."
		else
			view.prompt = game.op.type + ": Done."
	}
	return (game.op.spaces.length > 0) ? 1 : 0
}

function end_command() {
	log_br()
	game.op = null
	resume_event_card()
}

/* DECREES */

function gen_any_decree() {
	if (game.current === DS) {
		// view.actions.conscript = can_conscript() ? 1 : 0
	} else if (game.current === BK || game.current === VE) {
		view.actions.build = can_build() ? 1 : 0
	}
}

function can_build() {
	return has_piece(AVAILABLE, game.current, DISC)
}

function can_build_in_space(s) {
	return has_piece(s, game.current, ELITE)
}

/* TRIBUTARY AND REBELS */

function add_tributary(s) {
	game.tributary |= (1 << s)
	update_control()
}

function is_tributary(s) {
	return game.tributary & (1 << s)
}

function remove_tributary(s) {
	game.tributary &= ~(1 << s)
	update_control()
}

function to_obedient(p) {
	let faction = piece_faction(p)
	let piece_index = p - first_piece[faction][ELITE]
	game.rebel[faction] |= ~(1 << piece_index)
}

function to_rebel(p) {
	let faction = piece_faction(p)
	let piece_index = p - first_piece[faction][ELITE]
	console.log("with p ", p)
	console.log("with piece_index ", piece_index)
	console.log(game.rebel)
	game.rebel[faction] |= (1 << piece_index)
	console.log(game.rebel)
}

function to_rebel_space(s, faction) {
	let first = first_piece[faction][ELITE]
	let last = last_piece[faction][ELITE]
	for (let p = first; p <= last; ++p)
		if (piece_space(p) === s)
			to_rebel(p)
}

/* MISC SPACE + PIECE QUERIES */

function count_pieces(s, faction, type) {
	let first = first_piece[faction][type]
	let last = last_piece[faction][type]
	let n = 0
	for (let p = first; p <= last; ++p)
		if (piece_space(p) === s)
			++n
	return n
}

function count_faction_pieces(s, faction) {
	switch (faction) {
		case DS:
			return count_pieces(s, DS, TROOPS) + count_pieces(s, DS, ELITE) + count_pieces(s, DS, DISC)
		case BK:
			return count_pieces(s, BK, ELITE) + count_pieces(s, BK, DISC)
		case VE:
			return count_pieces(s, VE, ELITE) + count_pieces(s, VE, DISC)
		case MI:
			return count_pieces(s, MI, TROOPS)
	}
}

function has_majority(s) {
	let d = count_faction_pieces(s, DS)
	let b = count_faction_pieces(s, BK)
	let v = count_faction_pieces(s, VE)
	let m = count_faction_pieces(s, MI)

	if (d > b + v + m)
		return DS
	else if (b > d + v + m)
		return BK
	else if (v > b + d + m)
		return VE
	else if (m > b + d+ v)
		return MI
	else
		return -1
}

function has_piece(s, faction, type) {
	let first = first_piece[faction][type]
	let last = last_piece[faction][type]
	for (let p = first; p <= last; ++p)
		if (piece_space(p) === s)
			return true
	return false
}

function find_piece(s, faction, type) {
	let first = first_piece[faction][type]
	let last = last_piece[faction][type]
	for (let p = first; p <= last; ++p)
		if (piece_space(p) === s)
			return p
	return -1
}

function gen_place_piece(faction, type) {
	let p0 = first_piece[faction][type]
	let p1 = last_piece[faction][type]
	let can_place = false
	for (let p = p0; p <= p1; ++p) {
		if (piece_space(p) === AVAILABLE) {
			gen_action_piece(p)
			can_place = true
			if (type === DISC)
				break
		}
	}
	return can_place
}

function is_selected_cmd_space(s) {
	return game.op.spaces && set_has(game.op.spaces, s)
}

function place_piece(p, s) {
	if (piece_space(p) === AVAILABLE)
		p = find_piece(AVAILABLE, piece_faction(p), piece_type(p))

	set_piece_space(p, s)
	update_control()
}

function piece_faction(p) {
	if (p >= first_piece[MI][TROOPS] && p <= last_piece[MI][TROOPS])
		return MI
	if (p >= first_piece[DS][TROOPS] && p <= last_piece[DS][TROOPS])
		return DS
	if (p >= first_piece[DS][ELITE] && p <= last_piece[DS][ELITE])
		return DS
	if (p >= first_piece[BK][ELITE] && p <= last_piece[BK][ELITE])
		return BK
	if (p >= first_piece[VE][ELITE] && p <= last_piece[VE][ELITE])
		return VE
	if (p >= first_piece[DS][DISC] && p <= last_piece[DS][DISC])
		return DS
	if (p >= first_piece[BK][DISC] && p <= last_piece[BK][DISC])
		return BK
	if (p >= first_piece[VE][DISC] && p <= last_piece[VE][DISC])
		return VE
	throw "IMPOSSIBLE"
}

function piece_name(p) {
	return PIECE_FACTION_TYPE_NAME[piece_faction(p)][piece_type(p)]
}

function piece_type(p) {
	if (p >= first_piece[MI][TROOPS] && p <= last_piece[MI][TROOPS])
		return TROOPS
	if (p >= first_piece[DS][TROOPS] && p <= last_piece[DS][TROOPS])
		return TROOPS
	if (p >= first_piece[DS][ELITE] && p <= last_piece[DS][ELITE])
		return ELITE
	if (p >= first_piece[BK][ELITE] && p <= last_piece[BK][ELITE])
		return ELITE
	if (p >= first_piece[VE][ELITE] && p <= last_piece[VE][ELITE])
		return ELITE
	if (p >= first_piece[DS][DISC] && p <= last_piece[DS][DISC])
		return DISC
	if (p >= first_piece[BK][DISC] && p <= last_piece[BK][DISC])
		return DISC
	if (p >= first_piece[VE][DISC] && p <= last_piece[VE][DISC])
		return DISC
	throw "IMPOSSIBLE"
}

/* UTILS */

function add_resources(faction, n) {
	game.resources[faction] = Math.max(0, Math.min(24, game.resources[faction] + n))
}

function update_control() {
	game.control = [0, 0, 0]
	for (let s = first_space; s <= last_province; ++s) {
		if (is_tributary(s)) continue

		let c = has_majority(s)
		if (c <= VE)
			game.control[c] |= (1 << s)
	}
}

/* ACTIONS */

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

function gen_action_piece(p) {
	gen_action("piece", p)
}

function gen_action_space(s) {
	gen_action("space", s)
}

/* LOGGING */

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

function logi(msg) {
	log(">" + msg)
}

function log_br() {
	if (game.log.length > 0 && game.log[game.log.length - 1] !== "")
		game.log.push("")
}

function log_h1(msg) {
	log_br()
	log(".h1 " + msg)
	log_br()
}

function log_h2(msg) {
	log_br()
	log(".h2 " + msg)
	log_br()
}

function log_action(msg) {
	log_br()
	log(msg)
}

function log_transfer(msg) {
	log_br()
	log(".n " + msg)
	log_br()
}

function log_transfer_resources(from, to, n) {
	log_transfer(`${faction_name[from]} gave ${n} Resources to ${faction_name[to]}.`)
}

function log_space(s, action) {
	if (action)
		log_action("S" + s + " - " + action)
	else
		log_action("S" + s)
}

function push_summary() {
	if (game.summary)
		throw "TOO MANY SUMMARIES"
	game.summary = []
}

function log_summary(msg) {
	for (let item of game.summary) {
		if (item[1] === msg) {
			item[0]++
			return
		}
	}
	game.summary.push([1, msg])
}

function pop_summary() {
	if (game.summary.length > 0) {
		for (let [n, msg] of game.summary) {
			log(">" + msg.replace("%", String(n)))
		}
	} else {
		log(">Nothing")
	}
	game.summary = null
}

function log_summary_place(p) {
	let from = piece_space(p)
	if (from !== AVAILABLE)
		log_summary("% " + piece_name(p) + " from S" + from)
	else
		log_summary("% " + piece_name(p))
}

function log_summary_move_to_from(p, to) {
	log_summary("% " + piece_name(p) + " to S" + to + " from S" + piece_space(p))
}

function log_summary_remove(p) {
	log_summary("Removed % " + piece_name(p))
}

function log_resources(faction, n) {
	if (n > 0)
		log(faction_name[faction] + " Resources +" + n + ".")
	else
		log(faction_name[faction] + " Resources " + n + ".")
}

// === MISC PIECE QUERIES ===

function piece_space(p) {
	return game.pieces[p]
}

function set_piece_space(p, s) {
	game.pieces[p] = s
}


/* COMMON LIBRARY */

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

function push_undo() {
	if (game.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() {
	if (game.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_remove_item(array, item) {
	let n = array.length
	for (let i = 0; i < n; ++i)
		if (array[i] === item)
			return array_remove(array, i)
}

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, 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 {
			array_remove_pair(map, m<<1)
			return
		}
	}
}

function object_diff(a, b) {
	if (a === b)
		return false
	if (a !== null && b !== null && typeof a === "object" && typeof b === "object") {
		if (Array.isArray(a)) {
			if (!Array.isArray(b))
				return true
			let a_length = a.length
			if (b.length !== a_length)
				return true
			for (let i = 0; i < a_length; ++i)
				if (object_diff(a[i], b[i]))
					return true
			return false
		}
		for (let key in a)
			if (object_diff(a[key], b[key]))
				return true
		for (let key in b)
			if (!(key in a))
				return true
		return false
	}
	return true
}

// same as Object.groupBy
function object_group_by(items, callback) {
	let groups = {}
	if (typeof callback === "function") {
		for (let item of items) {
			let key = callback(item)
			if (key in groups)
				groups[key].push(item)
			else
				groups[key] = [ item ]
		}
	} else {
		for (let item of items) {
			let key = item[callback]
			if (key in groups)
				groups[key].push(item)
			else
				groups[key] = [ item ]
		}
	}
	return groups
}


// === CONST ===

// Factions
const DS = 0
const BK = 1
const VE = 2
const MI = 3

// Role names
const NAME_DS = "DS"
const NAME_BK = "BK"
const NAME_VE = "VE"
const NAME_SOLO = "Solo"

// Player pieces types
const DISC = 0
const ELITE = 1
const TROOPS = 2

// Pieces status
const AVAILABLE = -1
const OUT_OF_PLAY = -2
const ANY_PIECES = [ DISC, ELITE, TROOPS ]
const PIECE_FACTION_TYPE_NAME = [
	[ "Qasbah", "Governor", "Troops" ],
	[ "Fort", "Amir", null ],
	[ "Temple", "Raja", null ],
	[ null, null, "Invader" ]
]

// Sequence of Play options
const ELIGIBLE = 0
const SOP_LIMITED_COMMAND = 1
const SOP_COMMAND_DECREE = 2
const SOP_EVENT_OR_COMMAND = 3
const SOP_PASS = 4
const INELIGIBLE = 5
// === CONST ===