local mf = require('Module:Mapframe')
local getArgs = require('Module:Arguments').getArgs
local yesno = require('Module:Yesno')
local infoboxImage = require('Module:InfoboxImage').InfoboxImage

-- Defaults
local DEFAULT_FRAME_WIDTH = "270"
local DEFAULT_FRAME_HEIGHT = "200"
local DEFAULT_ZOOM = 10
local DEFAULT_GEOMASK_STROKE_WIDTH = "1"
local DEFAULT_GEOMASK_STROKE_COLOR = "#777777"
local DEFAULT_GEOMASK_FILL = "#888888"
local DEFAULT_GEOMASK_FILL_OPACITY = "0.25"
local DEFAULT_SHAPE_STROKE_WIDTH = "2"
local DEFAULT_SHAPE_STROKE_COLOR = "#FF0000"
local DEFAULT_SHAPE_FILL = "#606060"
local DEFAULT_SHAPE_FILL_OPACITY = "0.1"
local DEFAULT_LINE_STROKE_WIDTH = "5"
local DEFAULT_LINE_STROKE_COLOR = "#FF0000"
local DEFAULT_MARKER_COLOR = "#5E74F3"

local util = {}

function util.noop(info)
	local DEFAULT_NOOP_OUTPUT = ""

	-- uncomment this when debugging
	-- DEFAULT_NOOP_OUTPUT = "debug: mapframe no-op: " .. info
	-- mw.log(DEFAULT_NOOP_OUTPUT)

	return DEFAULT_NOOP_OUTPUT
end

-- Trim whitespace from args, and remove empty args
function util.trimArgs(argsTable)
	local cleanArgs = {}
	for key, val in pairs(argsTable) do
		if type(val) == 'string' then
			val = val:match('^%s*(.-)%s*$')
			if val ~= '' then
				cleanArgs[key] = val
			end
		else
			cleanArgs[key] = val
		end
	end
	return cleanArgs
end

function util.getBestStatement(item_id, property_id)
	if not(item_id) or not(mw.wikibase.isValidEntityId(item_id)) or not(mw.wikibase.entityExists(item_id)) then
		return false
	end
	local statements = mw.wikibase.getBestStatements(item_id, property_id)
	if not statements or #statements == 0 then
		return false
	end
	local hasNoValue = ( statements[1].mainsnak and statements[1].mainsnak.snaktype == 'novalue' )
	if hasNoValue then
		return false
	end
	return statements[1]
end

function util.hasWikidataProperty(item_id, property_id)
	return util.getBestStatement(item_id, property_id) and true or false
end

function util.getStatementValue(statement)
	return statement and statement.mainsnak and statement.mainsnak.datavalue and statement.mainsnak.datavalue.value or nil
end

function util.relatedEntity(item_id, property_id)
	local value = util.getStatementValue( util.getBestStatement(item_id, property_id) )
	return value and value.id or false
end

function util.idType(id)
	if not id then 
		return nil
	elseif mw.ustring.match(id, "[Pp]%d+") then
		return "property"
	elseif mw.ustring.match(id, "[Qq]%d+") then
		return "item"
	else
		return nil
	end
end

function util.shouldAutoRun(frame)
	-- Check if should be running
	local pargs = frame.getParent(frame).args
	local explicitlyOn = yesno(mw.text.trim(pargs.mapframe or "")) -- true of false or nil
	if pargs.coordinates == "{{{coordinates}}}" then explicitlyOn = false end
	local onByDefault = (explicitlyOn == nil) and yesno(mw.text.trim(frame.args.onByDefault or ""), false) -- true or false
	return explicitlyOn or onByDefault
end

function util.argsFromAuto(frame)
	-- Get args from the frame (invoke call) and the parent (template call).
	-- Frame arguments are default values which are overridden by parent values
	-- when both are present
	local args = getArgs(frame, {parentFirst = true})

	-- Discard args not prefixed with "mapframe-", remove that prefix from those that remain
	local fixedArgs = {}
	for name, val in pairs(args) do
		local fixedName = string.match(name, "^mapframe%-(.+)$" )
		if fixedName then
			fixedArgs[fixedName] = val
		-- allow coord, coordinates, etc to be unprefixed
		elseif name == "coordinates" or name == "coord" or name == "coordinate" and not fixedArgs.coord then
			fixedArgs.coord = val
		-- allow id, qid to be unprefixed, map to id (if not already present)
		elseif name == "id" or name == "qid" and not fixedArgs.id then
			fixedArgs.id = val
        -- allow captionstyle to be unprefixed, for compatibility with [[Module:Infobox]]
        elseif name == "captionstyle" and not fixedArgs.captionstyle then
            fixedArgs.captionstyle = val
		end
	end
	return fixedArgs
end


function util.parseCustomWikitext(customWikitext)
	-- infoboxImage will format an image if given wikitext containing an
	-- image, or else pass through the wikitext unmodified
	return infoboxImage({
		args = {
			image = customWikitext
		}
	})
end

function util.trackAndWarn(trackingCat, warning)
    local title = mw.title.getCurrentTitle()
    local results = title and title.namespace == 0 and trackingCat and '[[Category:'..trackingCat..']]' or ''
    if warning then
        local warn = require('Module:If preview')._warning
        results = results..warn({warning})
    end
    return results
end


function util.ternary(flag, other)
    other = other or 'other'
    flag = flag == 'none' and 'no' or flag
    local yesNoOut = yesno(flag,other)
    local yes = (yesNoOut == true)
    local no = (yesNoOut == false)
    return yes, no
end

local p = {}


p._caption = function(args)
	if args.caption then
		return args.caption
	elseif args.switcher then 
		return util.noop("no caption or switcher")
	end
	local maskItem
	local maskType = util.idType(args.geomask)
	if maskType == 'item' then
		maskItem = args.geomask
	elseif maskType == "property" then
		maskItem = util.relatedEntity(args.id or mw.wikibase.getEntityIdForCurrentPage(), args.geomask)
	end
	local maskItemLabel = maskItem and mw.wikibase.getLabel( maskItem )
	return maskItemLabel and "Location in "..maskItemLabel
		or util.noop("missing maskItemLabel with type " .. (maskType or "nil") .. " and item " .. (maskItem or "nil"))
end


--A list of types for objects that are too small to allow Kartographer to take over zoom
local tinyType = {
    landmark=true,
    railwaystation=true,
    edu=true,
    pass=true,
    camera=true
}                 

p._main = function(_config)
    -- accumulate tracking cats
    local tracking = ''
	-- `config` is the args passed to this module
	local config = util.trimArgs(_config)
	
    -- allow alias for config.coord
    config.coord = config.coord or config.coordinates

	-- Require wikidata item, or specified coords
	local wikidataId = config.id or mw.wikibase.getEntityIdForCurrentPage()
	if not(wikidataId) and not(config.coord) then
		return false, util.trackAndWarn('Pages using infobox mapframe with missing coordinates')
	end

	-- Require coords (specified or from wikidata), so that map will be centred somewhere
	-- (P625 = coordinate location)
    local wdCoordinates = util.getStatementValue(util.getBestStatement(wikidataId, 'P625'))
    if not (config.coord or wdCoordinates) then
		return false, util.trackAndWarn('Pages using infobox mapframe with missing coordinates')
	end

	-- `args` is the arguments which will be passed to the mapframe module
	local args = {}

	-- Some defaults/overrides for infobox presentation
	args.display = "inline"
	args.frame = "yes"
	args.plain = "yes"
	args["frame-width"]  = config["frame-width"] or config.width or DEFAULT_FRAME_WIDTH
	args["frame-height"] = config["frame-height"] or config.height or DEFAULT_FRAME_HEIGHT
	args["frame-align"]  = "center"

	args["frame-coord"] = config["frame-coordinates"] or config["frame-coord"]
	-- Note: config["coordinates"] or config["coord"] should not be used for the alignment of the frame;
	-- see talk page ( https://en.wikipedia.org/wiki/Special:Diff/876492931 )

	-- deprecated lat and long parameters
	args["frame-lat"]    = config["frame-lat"] or config["frame-latitude"]
	args["frame-long"]   = config["frame-long"] or config["frame-longitude"]

    -- if zoom isn't specified from config, first check wikidata
    local zoom = config.zoom or util.getStatementValue(util.getBestStatement(wikidataId, 'P6592'))
    if not zoom then
	    -- Calculate zoom from length or area (converted to km or km2)
	    -- Zoom so that length or area is completely included in mapframe
	    local getZoom = require('Module:Infobox dim')._zoom
	    zoom = getZoom({length_km=config.length_km, length_mi=config.length_mi,
                        width_km=config.width_km, width_mi=config.width_mi,
		                area_km2=config.area_km2, area_mi2=config.area_mi2,
                        area_ha=config.area_ha, area_acre=config.area_acre,
                        type=config.type, population=config.population,
		                viewport_px=math.min(args["frame-width"],args["frame-height"]),
                        latitude=wdCoordinates and wdCoordinates.latitude})
    end
    args.zoom = zoom or DEFAULT_ZOOM

	-- Use OSM relation ID if available; otherwise use geoshape if that is available
	-- (geoshape is required for defunct entities, which are outside OSM's scope)
	local hasOsmRelationId = util.hasWikidataProperty(wikidataId, 'P402') -- P402 is OSM relation ID
	local hasGeoshape = util.hasWikidataProperty(wikidataId, 'P3896') -- P3896 is geoshape
	local wikidataProvidesGeo = hasOsmRelationId or hasGeoshape

    -- determine marker argument value, determine whether to show marker
    local forcePoint, suppressPoint = util.ternary(config.point)
    local forceMarker, suppressMarker = util.ternary(config.marker,true)

    forcePoint = forcePoint or forceMarker
    suppressPoint = suppressPoint or suppressMarker

    local showMarker = not suppressPoint and (forcePoint or not wikidataProvidesGeo or config.coord)
    
    -- wikidata = "yes" turns on both shape and line
    -- wikidata = "no" turns off both shape and line
    -- otherwise show both if wikidata provides geo
    local forceWikidata, suppressWikidata = util.ternary(config.wikidata)
    local showShape = not suppressWikidata and (forceWikidata or wikidataProvidesGeo or not config.coord)
    local showLine = showShape

    -- determine shape parameter value, determine whether to show or suppress shape
    -- also determine whether to invert shape
    local forceShape, suppressShape = util.ternary(config.shape)
    showShape = wikidataId and not suppressShape and (forceShape or showShape)
	local shapeType = config.shape == 'inverse' and 'shape-inverse' or 'shape'

    -- determine line parameter value, determine whether to show or suppress line
    local forceLine, suppressLine = util.ternary(config.line)
    showLine = wikidataId and not suppressLine and (forceLine or showLine)

    local maskItem
	-- Switcher
	if config.switcher == "zooms" then
		-- switching between zoom levels
		local maxZoom = math.max(tonumber(args.zoom), 3) -- what zoom would have otherwise been (if 3 or more, otherwise 3)
		local minZoom = 1 -- completely zoomed out
		local midZoom = math.floor((maxZoom + minZoom)/2) -- midway between maxn and min
		args.switch = "zoomed in, zoomed midway, zoomed out"
		args.zoom = string.format("SWITCH:%d,%d,%d", maxZoom, midZoom, minZoom)
	elseif config.switcher == "auto" then
		-- switching between P276 and P131 areas with recursive lookup, e.g. item's city,
		-- that city's state, and that state's country
		args.zoom = nil -- let kartographer determine the zoom
		local maskLabels = {}
		local maskItems = {}
		local maskItemId = util.relatedEntity(wikidataId, "P276") or  util.relatedEntity(wikidataId, "P131") 
		local maskLabel = mw.wikibase.getLabel(maskItemId)
		while maskItemId and maskLabel and mw.text.trim(maskLabel) ~= "" do
			table.insert(maskLabels, maskLabel)
			table.insert(maskItems, maskItemId)
			maskItemId = maskItemId and util.relatedEntity(maskItemId, "P131")
			maskLabel = maskItemId and mw.wikibase.getLabel(maskItemId)
		end
		if #maskLabels > 1 then
			args.switch = table.concat(maskLabels, "###")
			maskItem = "SWITCH:" .. table.concat(maskItems, ",")
		elseif #maskLabels == 1 then
			maskItem = maskItemId[1]
		end
	elseif config.switcher == "geomasks" and config.geomask then
		-- switching between items in geomask parameter
		args.zoom = nil -- let kartographer determine the zoom
		local separator = (mw.ustring.find(config.geomask, "###", 0, true ) and "###") or
			(mw.ustring.find(config.geomask, ";", 0, true ) and ";") or ","
		local pattern = "%s*"..separator.."%s*"
		local maskItems = mw.text.split(mw.ustring.gsub(config.geomask, "SWITCH:", ""), pattern)
		local maskLabels = {}
		if #maskItems > 1 then
			for i, item in ipairs(maskItems) do
				table.insert(maskLabels, mw.wikibase.getLabel(item))
			end
			args.switch = table.concat(maskLabels, "###")
			maskItem = "SWITCH:" .. table.concat(maskItems, ",")
		end
	end
	
	-- resolve geomask item id (if not using geomask switcher)
	if not maskItem then --  
		local maskType = util.idType(config.geomask)
		if maskType == 'item' then
			maskItem = config.geomask
		elseif maskType == "property" then
			maskItem = util.relatedEntity(wikidataId, config.geomask)
		end
	end

    -- if asking for shape or line from Wikidata
    -- and if Wikidata actually has shape/line data (wikidataProvidesGeo=true)
    -- and if no geomask
    -- and if zoom not explicitly set
    -- and if the object size inferred from its type is not too small
    -- then let Kartographer "take over" zoom
    if (showLine or showShape) and wikidataProvidesGeo and not maskItem
       and not config.zoom and not (config.type and tinyType[config.type]) then
	    args.zoom = nil
    end	

    if not maskItem and not showShape and not showLine and not showMarker then
        return false, util.trackAndWarn('Pages using infobox mapframe with no geometry','No geometry specified for mapframe')
    end
	
	-- Keep track of arg numbering
	local argNumber = ''
	local function incrementArgNumber()
		if argNumber == '' then
			argNumber = 2
		else
			argNumber = argNumber + 1
		end
	end
	
	-- Geomask
	if maskItem then
		args["type"..argNumber] = "shape-inverse"
		args["id"..argNumber] = maskItem
		args["stroke-width"..argNumber] = config["geomask-stroke-width"] or DEFAULT_GEOMASK_STROKE_WIDTH
		args["stroke-color"..argNumber] = config["geomask-stroke-color"] or config["geomask-stroke-colour"] or DEFAULT_GEOMASK_STROKE_COLOR
		args["fill"..argNumber] = config["geomask-fill"] or DEFAULT_GEOMASK_FILL
		args["fill-opacity"..argNumber] = config["geomask-fill-opacity"] or DEFAULT_SHAPE_FILL_OPACITY
		-- Let kartographer determine zoom and position, unless it is explicitly set in config
		if not config.zoom and not config.switcher then
			args.zoom = nil
			args["frame-coord"] = nil
			args["frame-lat"] = nil
			args["frame-long"] = nil 	
			local maskArea = util.getStatementValue( util.getBestStatement(maskItem, 'P2046') )
		end
		incrementArgNumber()
		-- Hack to fix phab:T255932
		if not args.zoom then
			args["type"..argNumber] = "line"
			args["id"..argNumber] = maskItem
			args["stroke-width"..argNumber] = 0
			incrementArgNumber()
		end
	end
	
	-- Shape (or shape-inverse)
	if showShape then
		args["type"..argNumber] = shapeType
		if hasGeoshape and not hasOsmRelationId then
			args["from"..argNumber] = string.sub( util.getStatementValue( util.getBestStatement(wikidataId, 'P3896') ), 6)
		elseif config.id then 
			args["id"..argNumber] = config.id
		end
		args["stroke-width"..argNumber] = config["shape-stroke-width"] or config["stroke-width"] or DEFAULT_SHAPE_STROKE_WIDTH
		args["stroke-color"..argNumber] = config["shape-stroke-color"] or config["shape-stroke-colour"] or config["stroke-color"] or config["stroke-colour"] or DEFAULT_SHAPE_STROKE_COLOR
		args["fill"..argNumber] = config["shape-fill"] or DEFAULT_SHAPE_FILL
		args["fill-opacity"..argNumber] = config["shape-fill-opacity"] or DEFAULT_SHAPE_FILL_OPACITY
		incrementArgNumber()
	end
	
	-- Line
	if showLine then
		args["type"..argNumber] = "line"
		if hasGeoshape and not hasOsmRelationId then
			args["from"..argNumber] = string.sub( util.getStatementValue( util.getBestStatement(wikidataId, 'P3896') ), 6)
		elseif config.id then 
			args["id"..argNumber] = config.id
		end
		args["stroke-width"..argNumber] = config["line-stroke-width"] or config["stroke-width"] or DEFAULT_LINE_STROKE_WIDTH
		args["stroke-color"..argNumber] = config["line-stroke-color"] or config["line-stroke-colour"] or config["stroke-color"] or config["stroke-colour"] or DEFAULT_LINE_STROKE_COLOR
		incrementArgNumber()
	end

	-- Point marker
	if showMarker then
		args["type"..argNumber] = "point"
		if config.id then args["id"..argNumber] = config.id end
		if config.coord then args["coord"..argNumber] = config.coord end
		if config.marker then args["marker"..argNumber] = config.marker end
		args["marker-color"..argNumber] = config["marker-color"] or config["marker-colour"] or DEFAULT_MARKER_COLOR
		incrementArgNumber()
	end

    -- if Wikidata doesn't link to OSM and the map has no mask or point,
    -- then center the map on the coordinates either from the infobox or from wikidata
    if not maskItem and not showMarker and not wikidataProvidesGeo then
        if config.coord then
            args["frame-coord"] = args["frame-coord"] or config.coord
        else
            args["frame-lat"] = args["frame-lat"] or wdCoordinates.latitude
            args["frame-long"] = args["frame-long"] or wdCoordinates.longitude
        end
        tracking = tracking..util.trackAndWarn('Pages using infobox mapframe with forced centering')
    end

    -- protect against nil frame arguments
    args["frame-coord"] = args["frame-coord"] or ""
    args["frame-lat"] = args["frame-lat"] or ""
    args["frame-long"] = args["frame-long"] or ""

	local mapframe = args.switch and mf.multi(args) or mf._main(args)
	tracking = tracking..((showLine or showShape) and not wikidataProvidesGeo 
                          and util.trackAndWarn('Pages using infobox mapframe without shape links in Wikidata')
                          or '')
	return true, mapframe.. tracking
end

-- Entry points

p.main = function(frame)
	local parent = frame.getParent(frame)
	local parentArgs = parent.args
	local _, mapframe = p._main(parentArgs)
	return frame:preprocess(mapframe)
end

p.auto = function(frame)
	if not util.shouldAutoRun(frame) then
		return util.noop("auto should not autorun")
	end
	local args = util.argsFromAuto(frame)
	if args.custom then
		return frame:preprocess(util.parseCustomWikitext(args.custom))
	end
	local _, mapframe = p._main(args)
	return frame:preprocess(mapframe)
end

p.autocaption = function(frame)
	if not util.shouldAutoRun(frame) then
		return util.noop("autocaption should not autorun")
	end
	local args = util.argsFromAuto(frame)
    local caption = p._caption(args)
    return caption
end

p.autoWithCaption = function(frame)
	if not util.shouldAutoRun(frame) then
		return util.noop("autoWithCaption should not autorun")
	end
	local args = util.argsFromAuto(frame)
    local wikitext
    local caption
    local ok
    if args.custom then
        ok = true
        wikitext = util.parseCustomWikitext(args.custom)
    else
        ok, wikitext = p._main(args)
    end
    if not ok then return wikitext end
    wikitext = frame:preprocess(wikitext)
    caption = p._caption(args)
    local data = mw.html.create():wikitext(wikitext)
    data:tag('div')
	    :addClass('infobox-caption')
		:cssText(args.captionstyle)
		:wikitext(caption)
    return tostring(data)
end
    
return p