"use strict"

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

/* DATA */

// const data = require("./data.js")

const space_name = [
	"Andhra",
	"Bengal",
	"Gondwana",
	"Gujarat",
	"Jaunpur",
	"Karnataka",
	"Madhyadesh",
	"Maharashtra",
	"Malwa",
	"Orissa",
	"Rajput Kingdoms",
	"Sindh",
	"Tamilakam",
	"Delhi",
	"Mountain Passes",
	"Punjab",
	"Mongol Invaders",
	"DS Available",
	"BK Available",
	"VE Available",
]

const S_ANDHRA = 0
const S_BENGAL = 1
const S_GONDWANA = 2
const S_GUJARAT = 3
const S_JAUNPUR = 4
const S_KARNATAKA = 5
const S_MADHYADESH = 6
const S_MAHARASHTRA = 7
const S_MALWA = 8
const S_ORISSA = 9
const S_RAJPUT_KINGDOMS = 10
const S_SINDH = 11
const S_TAMILAKAM = 12
const S_DELHI = 13
const S_MOUNTAIN_PASSES = 14
const S_PUNJAB = 15
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

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

// 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 faction_name = [ "Delhi Sultanate", "Bahmani Kingdom", "Vijayanagara Empire" ]

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

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: [ 18, 0, 0 ],
		resources: [ 12, 6, 7 ],
		bk_inf: 0,
		ve_inf: 0,
		deck: [ this_card, deck_size, game.of_gods_and_kings ],
	}

	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 ],
		bk_inf: 0,
		ve_inf: 0,
		tributary: 8191, // all 13 provinces
		rebel: 0, // amir/raja rebel status
		pieces: [], // piece locations

		deck: [],
	}

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

	// TODO: setup start pieces

	// goto_card()

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

	return save_game()
}

/* 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))
}


/* 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
}