--[[
    PIN Terminal Node
    -----------------
    This file defines the PIN Terminal, which allows players to
    set their initial PIN, change it, and request a new card.
    It provides an immersive replacement for the /set_pin command.
--]]

-- Shows the form for a new player to set their first PIN.
local function show_pin_create_form(player, error_msg)
    local player_name = player:get_player_name()
    local formspec = "size[8,5]" ..
        "label[1,0.5;"..S("Welcome! Please set your personal 4-digit PIN.").."]" ..
        "pwdfield[2,2;4,1;new_pin;"..S("New PIN:").."]" ..
        "button_exit[3,4;2,1;confirm_new_pin;"..S("Confirm").."]"
    
    if error_msg then
        formspec = formspec .. "label[1,3;`"..minetest.formspec_escape(S(error_msg)).."`]" .. "style[label;color=red]"
    end

    minetest.show_formspec(player_name, "bank_accounts:pin_create", formspec)
end

-- Shows the main menu for an existing player at the PIN terminal.
local function show_pin_options_form(player)
    local player_name = player:get_player_name()
    minetest.show_formspec(player_name, "bank_accounts:pin_options",
        "size[8,6]" ..
        "label[1,0.5;"..S("PIN & Card Service").."]" ..
        "label[1,1.5;"..S("What would you like to do?").."]" ..
        "button_exit[2,3;4,1;change_pin;"..S("Change PIN").."]" ..
        "button_exit[2,4;4,1;new_card;"..S("Request New Card").."]")
end

-- Shows the form to change an existing PIN.
-- Can display an error message if something goes wrong.
local function show_pin_change_form(player, error_msg)
    local player_name = player:get_player_name()
    local formspec = "size[8,7]" ..
        "label[1,0.5;"..S("Change Your PIN").."]" ..
        "pwdfield[2,2;4,1;old_pin;"..S("Old PIN:").."]" ..
        "pwdfield[2,3;4,1;new_pin1;"..S("New PIN:").."]" ..
        "pwdfield[2,4;4,1;new_pin2;"..S("Confirm New PIN:").."]" ..
        "button_exit[3,6;2,1;confirm_change;"..S("Confirm").."]"
    
    if error_msg then
        formspec = formspec .. "label[1,5;`"..minetest.formspec_escape(S(error_msg)).."`]" .. "style[label;color=red]"
    end
    
    minetest.show_formspec(player_name, "bank_accounts:pin_change", formspec)
end

-- Node definition for the PIN Terminal.
minetest.register_node("bank_accounts:pin_terminal", {
    description = S("PIN Terminal"),
    drawtype = "mesh",
    mesh = "card_swipe.obj",
    paramtype = "light",
    paramtype2 = "facedir",
    tiles = {"pin_terminal.png"},
    groups = {cracky=3, crumbly=3, oddly_breakable_by_hand=2},

    -- Called when a player right-clicks the node.
    -- It does not require a card to operate.
    on_rightclick = function(pos, node, player, itemstack, pointed_thing)
        local player_name = player:get_player_name()
        -- Check if the player is new (has the default PIN).
        if bank_accounts.get_pin(player_name) == "0000" then
            show_pin_create_form(player)
        else
            show_pin_options_form(player)
        end
    end,
})

-- Handles formspec submissions for all PIN Terminal forms.
minetest.register_on_player_receive_fields(function(player, formname, fields)
    -- Only process forms belonging to this node.
    if not formname:find("bank_accounts:pin_") then
        return
    end

    local player_name = player:get_player_name()

    -- Logic for initial PIN creation.
    if formname == "bank_accounts:pin_create" then
        if fields.confirm_new_pin then
            local new_pin = fields.new_pin
            if new_pin and new_pin:match("^[0-9][0-9][0-9][0-9]$") and new_pin ~= "0000" then
                bank_accounts.set_pin(player_name, new_pin)
                local inv = player:get_inventory()
                if not inv:contains_item("main", "bank_accounts:atm_card") then
                    inv:add_item("main", "bank_accounts:atm_card")
                end
                minetest.chat_send_player(player_name, S("[PIN Terminal] Your PIN has been set! Your new bank card is in your inventory."))
            else
                -- Re-show form with an error message.
                show_pin_create_form(player, "[PIN Terminal] Your PIN must be 4 digits and not '0000'.")
            end
        end
    
    -- Logic for the options menu.
    elseif formname == "bank_accounts:pin_options" then
        if fields.change_pin then
            show_pin_change_form(player)
        elseif fields.new_card then
            local inv = player:get_inventory()
            if inv:contains_item("main", "bank_accounts:atm_card") then
                minetest.chat_send_player(player_name, S("[PIN Terminal] You already have a bank card."))
            else
                inv:add_item("main", "bank_accounts:atm_card")
                minetest.chat_send_player(player_name, S("[PIN Terminal] A new bank card has been added to your inventory."))
            end
        end

    -- Logic for the PIN change form.
    elseif formname == "bank_accounts:pin_change" then
        if fields.confirm_change then
            local old_pin = fields.old_pin
            local new_pin1 = fields.new_pin1
            local new_pin2 = fields.new_pin2

            if old_pin ~= bank_accounts.get_pin(player_name) then
                show_pin_change_form(player, "[PIN Terminal] Your old PIN is incorrect.")
            elseif not new_pin1 or not new_pin1:match("^[0-9][0-9][0-9][0-9]$") or new_pin1 == "0000" then
                 show_pin_change_form(player, "[PIN Terminal] Your PIN must be 4 digits and not '0000'.")
            elseif new_pin1 ~= new_pin2 then
                show_pin_change_form(player, "[PIN Terminal] The new PINs do not match.")
            else
                bank_accounts.set_pin(player_name, new_pin1)
                minetest.chat_send_player(player_name, S("[PIN Terminal] Your PIN has been successfully changed."))
            end
        end
    end
end)