require 'Амодуль:No globals'

local p = {}

local lib = require 'Амодуль:Wikidata/lib'
local i18n = mw.loadData('Амодуль:Wikidata/i18n')

local getArgs = (require 'Амодуль:Arguments').getArgs

local function outputBool(arg, ifexpr)
	local map
	if ifexpr then
		map = { [true] = 1, [false] = 0 }
	else
		map = { [true] = 1, [false] = '' }
	end
	return map[arg]
end

-- todo: move to lib
local function augmentArgs(args, defaults, prefix)
	local out = {}
	prefix = prefix or ''
	setmetatable(out, {
		__index = function (t, key)
			return args[prefix .. key] or defaults[key]
		end,
	})
	return out
end

local function getEntityIdFromStatements(statements)
	for _, statement in ipairs(statements) do
		if lib.IsSnakValue(statement.mainsnak) then
			if statement.mainsnak.datavalue.type ~= 'wikibase-entityid' then
				error(lib.raiseInvalidDatatype('getEntityIdFromStatements',
					statement.mainsnak.datatype, {'wikibase-item', 'wikibase-property'}))
			end
			local Formatters = require 'Амодуль:Wikidata/Formatters'
			return Formatters.getRawValue(statement.mainsnak, {})
		end
		break
	end
	return nil
end

local function getEntityIdFromEntity(entity, prop)
	local prop = mw.ustring.upper(prop)
	local statements = entity:getBestStatements(prop)
	return getEntityIdFromStatements(statements)
end

local function getEntityIdFromId(id, prop)
	local prop = mw.ustring.upper(prop)
	local statements = mw.wikibase.getBestStatements(id, prop)
	return getEntityIdFromStatements(statements)
end

local function getIdFromTitle(titleString, wiki)
	if wiki then
		return mw.wikibase.getEntityIdForTitle(titleString, wiki)
	end
	local title = mw.title.new(titleString)
	while title do
		local id = mw.wikibase.getEntityIdForTitle(title.prefixedText)
		if id then
			return id
		end
		title = title.redirectTarget
	end
	return nil
end

local function findEntityId(options)
	local id
	if options.entity and type(options.entity) == 'table' then
		id = options.entity.id
	end
	if not id and options.page then
		id = getIdFromTitle(options.page, options.wiki)
		if not id then
			return nil
		end
	end
	if not id then
		id = options.id or p.getCurrentId()
	end
	if id and options.of then
		id = getEntityIdFromId(id, options.of)
	end
	return id
end

local function findEntity(options)
	local entity
	if options.entity and type(options.entity) == 'table' then
		entity = options.entity
	end
	if not entity then
		if options.id then
			local id = options.id:upper()
			entity = mw.wikibase.getEntity(id)
			if entity and entity.id ~= id then
				mw.log(id .. ' je přesměrování na ' .. entity.id)
			end
		else
			if options.page then
				local id = getIdFromTitle(options.page, options.wiki)
				if id then
					entity = mw.wikibase.getEntity(id)
				end
			else
				entity = mw.wikibase.getEntity()
			end
		end
	end
	if options.of then
		if entity then
			local id = getEntityIdFromEntity(entity, options.of)
			if id then
				return mw.wikibase.getEntity(id)
			end
		end
		return nil
	end
	return entity
end

local function getSitelink(options)
	local id = findEntityId(options)
	if not id then
		return nil
	end

	local site = options.site or options[1]
	local sitelink = mw.wikibase.getSitelink(id, site)

	if not sitelink then
		return nil
	end

	if options.pattern then
		sitelink = lib.formatFromPattern(sitelink, options.pattern)
	end
	if lib.IsOptionTrue(options, 'addclass') then
		sitelink = lib.addWdClass(sitelink)
	end
	return sitelink
end

local function formatStatementAndData(statement, options)
	if not statement.type or statement.type ~= 'statement' then
		error(lib.formatError('unknown-claim-type', statement.type or '[neznámý]')) -- fixme: i18n
	end
	local Filterers = require 'Амодуль:Wikidata/Filterers'
	local Formatters = require 'Амодуль:Wikidata/Formatters'

	local result = { Formatters.getFormattedValue(statement.mainsnak, options) }
	local qualifiers
	if statement.qualifiers and options.showqualifier then
		local PropList = lib.textToTable(options.showqualifier)
		-- todo: move this to a better place (config)
		local default_options = {
			isQualifier = true,
			label = 'short',
			nolink = lib.IsOptionTrue(options, 'nolink'),
			precision = 9,
		}
		for _, property in ipairs(PropList) do
			local property = mw.ustring.upper(property)
			local Values = {}
			local qualifiers_options = augmentArgs(options, default_options, 'qualifiers ')
			if statement.qualifiers[property] then
				local Qualifiers = mw.clone(statement.qualifiers[property])
				qualifiers_options.property = property
				if not qualifiers_options.nolink then
					qualifiers_options.nolink = (Qualifiers[1].datatype == 'time')
				end
				Filterers.filterQualifiers(Qualifiers, qualifiers_options)
				for _, snak in ipairs(Qualifiers) do
					table.insert(Values, Formatters.getFormattedValue(snak, qualifiers_options))
				end
			elseif property == 'TIME' then
				local Data = {}
				-- todo: factor out
				for key, array in pairs(lib.props) do
					for _, prop in ipairs(array) do
						for _, snak in ipairs(statement.qualifiers[prop] or {}) do
							if lib.IsSnakValue(snak) then -- dokud nebude jasné, jak to používat
								Data[key] = snak
								break
							end
						end
					end
				end
				if Data.begin or Data.ending then
					qualifiers_options.nolink = true
					table.insert(Values, lib.formatDateRange(Data, qualifiers_options))
				end
			end
			if #Values > 0 then
				-- TODO: remove duplicates
				result[property] = mw.text.listToText(Values, qualifiers_options.separator, qualifiers_options.conjunction)
			end
		end
	end
	if statement.references and lib.IsOptionTrue(options, 'showsource') then
		-- todo: configure custom formatter
		local Module = require 'Амодуль:Wikidata/cite'
		result.ref = Module.formatReferences(statement.references, options) -- or table of references?
	end
	return result
end

local function formatStatement(statement, options)
	local data = formatStatementAndData(statement, options)
	local result = data[1]
	if options.isQualifier == true then
		return result
	end

	local qualifiers
	if statement.qualifiers and options.showqualifier then
		local PropList = lib.textToTable(options.showqualifier)
		local tmp = {}
		for _, prop in ipairs(PropList) do
			local prop = mw.ustring.upper(prop)
			if data[prop] then
				table.insert(tmp, data[prop])
			end
		end
		if #tmp > 0 then
			qualifiers = table.concat(tmp, i18n['qualifiers separator'])
		end
	end
	if not qualifiers and options.showtargetdata then
		local entity
		local Filterers = require 'Амодуль:Wikidata/Filterers'
		local Formatters = require 'Амодуль:Wikidata/Formatters'
		if lib.IsSnakValue(statement.mainsnak) then
			if statement.mainsnak.datavalue.type == 'wikibase-entityid' then
				entity = mw.wikibase.getEntity(Formatters.getRawValue(statement.mainsnak, {}))
			else
				error(lib.formatError('invalid-datatype', statement.mainsnak.property, statement.mainsnak.datatype, 'wikibase-item/wikibase-property'))
			end
		end
		if entity then
			local PropList = lib.textToTable(options.showtargetdata)
			local date
			local rank = 'best'
			if options.targetdate then
				if lib.isPropertyId(options.targetdate) then
					date = p.getRawValueFromLua{ entity = options.entity, property = options.targetdate }
				else
					date = options.targetdate
				end
				if date then
					rank = 'valid'
				end
			end
			local options = {
				addclass = false,
				autoformat = true,
				date = date,
				entity = entity,
				isQualifier = true,
				label = 'short',
				nolink = true,
				precision = 9,
				rank = rank,
				sort = {'date'},
			}
			local Snaks = {}
			for _, property in ipairs(PropList) do
				local result
				if mw.ustring.lower(property) == 'time' then
					local Data = {}
					for key, array in pairs(lib.props) do
						for _, prop in ipairs(array) do
							options.property = prop
							local Statements = Filterers.filterStatementsFromEntity(entity, options)
							for _, statement in ipairs(Statements) do
								Data[key] = statement.mainsnak
								break
							end
						end
					end
					if Data.begin or Data.ending then
						result = lib.formatDateRange(Data, options)
					end
				else
					options.property = property
					result = p.formatStatementsFromLua(options)
				end
				if result then
					table.insert(Snaks, result)
				end
			end
			if #Snaks > 0 then
				qualifiers = table.concat(Snaks, i18n['qualifiers separator'])
			end
		end
	end

	if qualifiers then
		if options.delimiter then
			result = result .. options.delimiter .. qualifiers
		else
			result = result .. ' (' .. qualifiers .. ')'
		end
	end
	if data.ref and data.ref ~= '' then
		return result .. data.ref .. lib.category('references')
	end
	return result
end

local function formatStatements(statements, options)
	local formattedStatements = {}
	local set = {}
	for _, statement in ipairs(statements) do
		local formatted = formatStatement(statement, options)
		-- TODO: maybe make optional and move elsewhere
		if not set[formatted] then
			table.insert(formattedStatements, formatted)
			set[formatted] = true
		end
	end
	return formattedStatements
end

local function getStatements(id, options)
	if not id then
		return {}
	end
	local statements = mw.wikibase.getAllStatements(id, options.property:upper())
	local Filterers = require 'Амодуль:Wikidata/Filterers'
	Filterers.filterStatements(statements, options)
	return statements
end

local function prepareShowMore(options)
	if options.limit and lib.IsOptionTrue(options, 'showmore') then
		options.limit = options.limit + 1
		return true
	end
	return false
end

local function handleShowMore(values, limit, add_more)
	if add_more then
		if #values == limit then
			table.remove(values)
		else
			add_more = false
		end
	end
	return add_more
end

local function makeList(values, options, add_more, link)
	-- TODO: handle duplicates here
	if add_more then
		local parts = mw.text.split(link, '#', true) -- b/c
		table.insert(values, mw.ustring.format(i18n['more-on-Wikidata'], parts[1], parts[2] or ''))
	end
	local text
	if options.list == 'ul' or options.list == 'ol' then
		local li = {}
		for _, val in ipairs(values) do
			table.insert(li, mw.ustring.format('<li>%s</li>', val))
		end
		text = mw.ustring.format('<%s class="wd">%s</%s>', options.list, table.concat(li), options.list)
	else
		text = mw.text.listToText(values, options.separator, options.conjunction)
		if lib.IsOptionTrue(options, 'addlink') then
			-- TODO: data-bridge-edit-flow
			text = mw.ustring.format('%s <sup class="wd-link">([[d:%s|e]])</sup>', text, link)
		end
		if tostring(options.addclass) ~= 'false' then
			text = lib.addWdClass(text)
		end
	end
	return text
end

local function getFormattedStatements(options)
	options.limit = tonumber(options.limit) --TODO default?
	local add_more = prepareShowMore(options)
	local id = findEntityId(options)
	local statements = getStatements(id, options)

	if #statements == 0 then return nil end
	add_more = handleShowMore(statements, options.limit, add_more)

	options.id = id
	-- Format statements and concat them cleanly
	local formattedStatements = formatStatements(statements, options)
	local property = mw.ustring.upper(options.property)
	local link = mw.ustring.format('%s#%s', id, property)
	local text = makeList(formattedStatements, options, add_more, link)
	if lib.IsOptionTrue(options, 'addcat') then
		text = text .. lib.category('used-property', property)
	end
	return text
end

local function getRawValue(options)
	if not options.rank then
		options.rank = 'best'
	end
	for _, statement in ipairs(p.getStatements(options)) do
		local Formatters = require 'Амодуль:Wikidata/Formatters'
		return Formatters.getRawValue(statement.mainsnak, options)
	end
	return nil
end

local function getQualifiers(args)
	if not args.qualifier then
		error(lib.formatError('param-not-provided', 'qualifier'))
	end
	if not args.rank then
		args.rank = 'best'
	end
	for _, statement in ipairs(p.getStatements(args)) do
		if statement.qualifiers then
			local qualifier_args = augmentArgs(args, {}, 'qualifiers ')
			local qualifiers = mw.clone(statement.qualifiers[mw.ustring.upper(args.qualifier)] or {})
			local Filterers = require 'Амодуль:Wikidata/Filterers'
			Filterers.filterQualifiers(qualifiers, qualifier_args)
			return qualifiers
		end
		return {}
	end
	return {}
end

----- API pro šablony -----

function p.compareStatements(frame)
	local args = getArgs(frame, { frameOnly = true })
	return p._compareStatements(args)
end

function p.dumpWikidataEntity(frame)
	local args = getArgs(frame, { frameOnly = true })

	return mw.dumpObject( mw.wikibase.getEntity( args.id ) )
end

function p.getBadges(frame)
	local args = getArgs(frame, { frameOnly = true })
	local site = args.site
	if not site then
		error(lib.formatError('param-not-provided', 'site'))
	end
	local entity = findEntity(args)
	local Badges = {}
	if entity and entity.sitelinks and entity.sitelinks[site] then
		local Formatters = require 'Амодуль:Wikidata/Formatters'
		for _, badge in ipairs(entity.sitelinks[site].badges) do
			table.insert(Badges, Formatters.formatRawValue(badge, 'wikibase-entityid'))
		end
	end
	return table.concat(Badges, ', ')
end

function p.getLabel(frame)
	local args = getArgs(frame, { frameOnly = true })
	local id = findEntityId(args)
	if not id then
		return nil
	end
	local lang, label = args.lang
	if lang then
		label = mw.wikibase.getLabelByLang(id, lang)
	else
		label, lang = mw.wikibase.getLabelWithLang(id)
	end
	if not label then return nil end
	label = mw.text.nowiki(label)
	if lib.IsOptionTrue(args, 'addclass') then
		if lang ~= i18n.lang then
			return lib.addWdClass(lib.formatTextInLanguage(label, lang))
		else
			return lib.addWdClass(label)
		end
	end
	return label
end

function p.getDescription(frame)
	local args = getArgs(frame, { frameOnly = true })
	local id = findEntityId(args)
	if not id then
		return nil
	end
	local lang, description = args.lang
	if not lang or lang == i18n.lang then
		description, lang = mw.wikibase.getDescriptionWithLang(id)
	else
		local entity = mw.wikibase.getEntity(id)
		if entity then
			description, lang = entity:getDescriptionWithLang(lang)
		end
	end
	if not description then return nil end
	description = mw.text.nowiki(description)
	if lib.IsOptionTrue(args, 'addclass') then
		if lang ~= i18n.lang then
			return lib.addWdClass(lib.formatTextInLanguage(description, lang))
		else
			return lib.addWdClass(description)
		end
	end
	return description
end

function p.getAliases(frame)
	local args = getArgs(frame, { frameOnly = true })
	local entity = findEntity(args)
	local lang = args.lang or i18n.lang
	if not entity or not entity.aliases or not entity.aliases[lang] then
		return nil
	end

	args.limit = tonumber(args.limit)
	local add_more = prepareShowMore(args)
	local limit = args.limit

	local Aliases = {}
	for i, alias in ipairs(entity.aliases[lang]) do
		table.insert(Aliases, mw.text.nowiki(alias.value))
		if i == limit then
			break
		end
	end
	add_more = handleShowMore(Aliases, limit, add_more)
	return makeList(Aliases, args, add_more, entity.id)
end

function p.getId(frame)
	local args = getArgs(frame, {
		frameOnly = false,
		parentOnly = false,
		parentFirst = false,
	})

	if not args[1] then
		return mw.wikibase.getEntityIdForCurrentPage()
	end

	for _, titleString in ipairs(args) do
		local id = getIdFromTitle(titleString, args.wiki)
		if id then
			return id
		end
	end
	return nil
end

function p.getSitelink(frame)
	return getSitelink(getArgs(frame, { frameOnly = true }))
end

function p.formatStatements(frame)
	local args = getArgs(frame, { frameOnly = true })
	if args.value then return args.value end -- b/c for other wikis
	local parent_args = getArgs(frame, { parentOnly = true })
	local add
	if parent_args.item and not args.id then
		args.id = parent_args.item
		add = lib.category('arbitrary-data')
	end
	local value = getFormattedStatements(args)
	if add and value then
		return value .. add
	end
	return value
end

function p.formatStatementsFromTemplate(frame)
	local args = getArgs(frame, {
		frameOnly = false,
		parentOnly = false,
		parentFirst = false,
	})
	return getFormattedStatements(args)
end

function p.getCount(frame)
	local args = getArgs(frame, { frameOnly = true })
	args.limit = nil
	return #p.getStatements(args)
end

function p.getRawValue(frame)
	return getRawValue(getArgs(frame, { frameOnly = true }))
end

function p.getQualifier(frame)
	local args = getArgs(frame, { frameOnly = true })
	args.limit = tonumber(args['qualifiers limit'] or args.limit)
	local add_more = prepareShowMore(args)
	local limit = args.limit
	args['qualifiers limit'] = limit
	args.limit = 1
	local qualifiers = getQualifiers(args)
	if #qualifiers == 0 then
		return nil
	end

	add_more = handleShowMore(qualifiers, limit, add_more)
	local Formatters = require 'Амодуль:Wikidata/Formatters'
	local formattedQualifiers = {}
	for _, qualifier in ipairs(qualifiers) do
		table.insert(formattedQualifiers, Formatters.getFormattedValue(qualifier, args))
	end

	local link = '' -- TODO: we don't have statement anchor
	-- TODO: references?
	return makeList(formattedQualifiers, args, add_more, link)
end

function p.getRawQualifier(frame)
	local args = getArgs(frame, { frameOnly = true })
	args.limit = 1
	for _, qualifier in ipairs(getQualifiers(args)) do
		local Formatters = require 'Амодуль:Wikidata/Formatters'
		return Formatters.getRawValue(qualifier, args)
	end
	return nil
end

function p.getCurrentId()
	return mw.wikibase.getEntityIdForCurrentPage()
end

function p.formatEntity(frame)
	local args = getArgs(frame, { frameOnly = true })
	args.id = args.id or p.getCurrentId()
	if args.id then
		local Formatters = require 'Амодуль:Wikidata/Formatters'
		return Formatters.formatRawValue(args.id, 'wikibase-entityid', args)
	end
	return nil
end

function p.entityExists(frame)
	return outputBool(
		mw.wikibase.entityExists(frame.args.id or frame.args[1]),
		lib.IsOptionTrue(frame.args, 'ifexpr'))
end

function p.isValidEntityId(frame)
	return outputBool(
		mw.wikibase.isValidEntityId(frame.args.id or frame.args[1]),
		lib.IsOptionTrue(frame.args, 'ifexpr'))
end

----- Амодульқәа API -----

function p.formatStatementsFromLua(options)
	return getFormattedStatements(options)
end

function p.getSitelinkFromLua(options)
	return getSitelink(options or {})
end

function p.getStatements(args)
	local id = findEntityId(args)
	return getStatements(id, args)
end

function p.getStatementsWithData(args)
	local statements = p.getStatements(args)
	local result = {}
	for _, statement in ipairs(statements) do
		table.insert(result, formatStatementAndData(statement, args))
	end
	return result
end

function p.getRawValueFromLua(options)
	return getRawValue(options)
end

function p.getRawValues(options)
	local Values = {}
	local Formatters = require 'Амодуль:Wikidata/Formatters'
	for _, st in ipairs(p.getStatements(options)) do
		table.insert(Values, Formatters.getRawValue(st.mainsnak, options))
	end
	return Values
end

p.formatStatementsTable = formatStatements

function p._compareStatements(args)
	if not args.value then
		error(lib.formatError('param-not-provided', 'value'))
	end
	local statements = p.getStatements(args)
	local compare = require 'Амодуль:Wikidata/compare'
	return compare.compareValues(args.value, statements, args)
end

function p.ViewSomething(frame)
	local f = (frame.args[1] or frame.args.id) and frame or frame:getParent()
	local id = f.args.id
	if id and (#id == 0) then
		id = nil
	end
	local data = mw.wikibase.getEntity(id)
	if not data then
		return nil
	end

	local i = 1
	while true do
		local index = f.args[i]
		if not index then
			if type(data) == "table" then
				return mw.text.jsonEncode(data, mw.text.JSON_PRESERVE_KEYS + mw.text.JSON_PRETTY)
			else
				return tostring(data)
			end
		end

		data = data[index] or data[tonumber(index)]
		if not data then
			return
		end

		i = i + 1
	end
end

return p