--[[
This file is part of mpv.

mpv is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

mpv is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with mpv.  If not, see <http://www.gnu.org/licenses/>.
]]

local utils = require "mp.utils"
local input = {}

local handle_counter = 0
local latest_handler_id

local function get_non_callbacks(t)
    local non_callbacks = {}

    for key, value in pairs(t) do
        if type(value) ~= "function" then
            non_callbacks[key] = value
        end
    end

    return non_callbacks
end

local function register_event_handler(t)
    local handler_id = "input-event/"..handle_counter
    handle_counter = handle_counter + 1
    latest_handler_id = handler_id

    mp.register_script_message(handler_id, function (type, args)
        -- do not process events (other than closed) for an input that has been overwritten
        if latest_handler_id ~= handler_id and type ~= "closed" then
            return
        end

        if t[type] then
            local completions, completion_pos, completion_append =
                t[type](unpack(utils.parse_json(args or "") or {}))

            if type == "complete" and completions then
                mp.commandv("script-message-to", "console", "complete",
                            utils.format_json(completions), completion_pos,
                            completion_append or "")
            end
        end

        if type == "closed" then
            mp.unregister_script_message(handler_id)
        end
    end)

    return handler_id
end

function input.get(t)
    t.has_completions = t.complete ~= nil
    t.client_name = mp.get_script_name()
    t.handler_id = register_event_handler(t)

    mp.commandv("script-message-to", "console", "get-input",
                utils.format_json(get_non_callbacks(t)))
end

input.select = input.get

function input.terminate()
    mp.commandv("script-message-to", "console", "disable", utils.format_json({
                    client_name = mp.get_script_name(),
                }))
end

function input.log(message, style, terminal_style)
    mp.commandv("script-message-to", "console", "log", utils.format_json({
                   text = message,
                   style = style,
                   terminal_style = terminal_style,
               }))
end

function input.log_error(message)
    mp.commandv("script-message-to", "console", "log",
                 utils.format_json({ text = message, error = true }))
end

function input.set_log(log)
    mp.commandv("script-message-to", "console", "set-log", utils.format_json(log))
end

return input