-- history.lua — unbounded console history with a review cursor.
--
-- The game's own console buffer (modules/console.lua) is unusable as history: its
-- entries expire after 3 seconds and scroll away. We keep our own copy, appended
-- from a wrapper around console.print.
--
-- Coalescing mirrors the game exactly. console.print folds a repeated identical
-- message into the previous entry and bumps a `times` counter, drawing it as
-- "You feel cold (x3)". We do the same and speak the same string, so what is
-- heard matches what is on screen.

local speech = require("accessibility.speech")

local history = {}

local MAX_ENTRIES = 1000

local entries = {}
local reviewIndex = nil -- nil = following the tail (live)

--------------------------------------------------------------------------------
-- Rendering an entry
--------------------------------------------------------------------------------

local function entryText(entry)
	if not entry then
		return nil
	end

	if entry.times and entry.times > 1 then
		return entry.text .. " (x" .. entry.times .. ")"
	end

	return entry.text
end

history.entryText = entryText

--------------------------------------------------------------------------------
-- Appending
--------------------------------------------------------------------------------

-- Called from the console.print wrapper. Returns the text that should be spoken,
-- or nil if nothing should be.
function history.append(text, colorTemplate)
	text = speech.normalise(text)
	if not text then
		return nil
	end

	local last = entries[#entries]

	if last and last.text == text then
		-- Same fold the game performs.
		last.times = last.times + 1
		return entryText(last)
	end

	entries[#entries + 1] = {
		text = text,
		times = 1,
		colorTemplate = colorTemplate,
	}

	-- Trim from the front. Keep the review cursor pointing at the same entry.
	if #entries > MAX_ENTRIES then
		table.remove(entries, 1)
		if reviewIndex then
			reviewIndex = math.max(1, reviewIndex - 1)
		end
	end

	return entryText(entries[#entries])
end

function history.count()
	return #entries
end

function history.clear()
	entries = {}
	reviewIndex = nil
end

--------------------------------------------------------------------------------
-- Review cursor
--------------------------------------------------------------------------------

-- While reviewing, the cursor holds still as new lines arrive; it only follows the
-- tail when the user has not moved it. Otherwise reading back through a fight
-- would be yanked forward by every new message.

local function speakAt(index)
	if #entries == 0 then
		speech.interrupt("No messages")
		return
	end

	local entry = entries[index]
	if not entry then
		return
	end

	local position
	if index == 1 then
		position = "First message"
	elseif index == #entries then
		position = "Last message"
	end

	local text = entryText(entry)

	if position then
		-- Most game messages already end in punctuation; joining with ". " blindly
		-- gives "You hit the rat.. First message".
		local separator = text:match("[%.%!%?]$") and " " or ". "
		text = text .. separator .. position
	end

	speech.interrupt(text)
end

function history.reviewPrevious()
	if #entries == 0 then
		speech.interrupt("No messages")
		return
	end

	if reviewIndex == nil then
		-- Entering review from live: start at the newest, then step back one.
		reviewIndex = #entries
	end

	reviewIndex = math.max(1, reviewIndex - 1)
	speakAt(reviewIndex)
end

function history.reviewNext()
	if #entries == 0 then
		speech.interrupt("No messages")
		return
	end

	if reviewIndex == nil then
		speakAt(#entries)
		reviewIndex = #entries
		return
	end

	reviewIndex = math.min(#entries, reviewIndex + 1)
	speakAt(reviewIndex)
end

function history.reviewFirst()
	if #entries == 0 then
		speech.interrupt("No messages")
		return
	end

	reviewIndex = 1
	speakAt(reviewIndex)
end

function history.reviewLast()
	if #entries == 0 then
		speech.interrupt("No messages")
		return
	end

	reviewIndex = nil -- back to following live output
	speakAt(#entries)
end

function history.repeatCurrent()
	if #entries == 0 then
		speech.interrupt("No messages")
		return
	end

	speakAt(reviewIndex or #entries)
end

function history.copyCurrent()
	if #entries == 0 then
		return
	end

	local text = entryText(entries[reviewIndex or #entries])
	local ok = pcall(love.system.setClipboardText, text)
	speech.interrupt(ok and "Copied" or "Copy failed")
end

return history