-- surroundings.lua — probe the tiles around the player without moving anything.
--
-- The game's examine mode (ingame_observe) already walks a cursor around the map
-- and is now narrated, but entering it, stepping, and leaving is heavy when you
-- just want to know what is immediately next to you. This answers that in one
-- keypress, with no state change and no game side effects.

local speech = require("accessibility.speech")
local describe = require("accessibility.describe")

local surroundings = {}

-- Screen coordinates: +y is south.
local numpadDirections = {
	kp1 = {-1, 1},
	kp2 = {0, 1},
	kp3 = {1, 1},
	kp4 = {-1, 0},
	kp5 = {0, 0},
	kp6 = {1, 0},
	kp7 = {-1, -1},
	kp8 = {0, -1},
	kp9 = {1, -1},
}

-- Clockwise from north, which is how people scan a compass.
local scanOrder = {
	{0, -1, "north"},
	{1, -1, "north-east"},
	{1, 0, "east"},
	{1, 1, "south-east"},
	{0, 1, "south"},
	{-1, 1, "south-west"},
	{-1, 0, "west"},
	{-1, -1, "north-west"},
}

local function getLevel()
	local ok, world = pcall(require, "models.world")
	if not ok or not world.currentLevel then
		return nil
	end
	return world.currentLevel
end

local function playerPosition(level)
	local actor = level and level.playerActor
	if not actor or not actor.x or not actor.y then
		return nil
	end
	return actor.x, actor.y
end

--------------------------------------------------------------------------------
-- Probing
--------------------------------------------------------------------------------

-- Speak a single tile at an offset from the player.
function surroundings.probe(dx, dy)
	local level = getLevel()
	local px, py = playerPosition(level)

	if not px then
		return
	end

	if dx == 0 and dy == 0 then
		speech.say("Standing on: " .. describe.tile(level, px, py), true)
		return
	end

	speech.say(describe.tile(level, px + dx, py + dy, px, py), true)
end

-- All eight neighbours, clockwise from north, as one line. Terse by design:
-- eight descriptions at normal verbosity is a wall of speech.
--
-- Returns the text rather than speaking it, because melee targeting needs the
-- same sentence on entry (accessibility/states/ingame_targeting_melee.lua).
function surroundings.describeNeighbours()
	local level = getLevel()
	local px, py = playerPosition(level)

	if not px then
		return nil
	end

	local previousVerbosity = describe.verbosity
	describe.verbosity = "terse"

	local parts = {}
	for _, entry in ipairs(scanOrder) do
		local dx, dy, name = entry[1], entry[2], entry[3]
		local text = describe.tile(level, px + dx, py + dy)
		parts[#parts + 1] = name .. ", " .. text
	end

	describe.verbosity = previousVerbosity

	return table.concat(parts, ". ")
end

-- Speak all eight neighbours.
function surroundings.scan()
	local text = surroundings.describeNeighbours()
	if text then
		speech.say(text, true)
	end
end

-- Where am I: level name, in-game time, coordinates.
function surroundings.whereAmI()
	local level = getLevel()
	local px, py = playerPosition(level)

	if not px then
		return
	end

	local parts = {}

	if level.name then
		parts[#parts + 1] = level.name
	end

	local ok, world = pcall(require, "models.world")
	if ok and world.printableDatetime then
		parts[#parts + 1] = world.printableDatetime
	end

	parts[#parts + 1] = "position " .. px .. ", " .. py

	speech.say(table.concat(parts, ". "), true)
end

--------------------------------------------------------------------------------
-- Key registration
--------------------------------------------------------------------------------

function surroundings.registerKeys(hotkeys)
	-- Numpad probing is modifier-gated: kp1-kp9 are movement in game, so an
	-- unmodified numpad key must keep moving the player. Ctrl is the game's
	-- moveCamera modifier but that only acts on direction commands we consume
	-- here, so Ctrl+numpad is free.
	for scancode, offset in pairs(numpadDirections) do
		hotkeys.bind(scancode, "ctrl", function()
			surroundings.probe(offset[1], offset[2])
		end)
	end

	hotkeys.bind("/", nil, surroundings.scan)
	hotkeys.bind(";", nil, surroundings.whereAmI)
end

return surroundings