local function expect( value, name, expectedType )
    local actualType = type( value )

    if actualType != expectedType then
        error( string.format( 'TypeError: parameter %s has wrong type (%s expected, got %s)', name, expectedType, actualType ) )
    end
end

CommandManager = {
    prefixKeyword = 'aoki',
    prefixes = {
        '/',
        '!',
        '.',
    },
    commands = {},
    addCommand = function( params )
        expect( params.name, 'name', 'string' )
        expect( params.args, 'args', 'string' )
        expect( params.description, 'description', 'string' )
        expect( params.localPlayerOnly or false, 'localPlayerOnly', 'boolean' )
        expect( params.friendsOnly or false, 'friendsOnly', 'boolean' )
        expect( params.callback, 'callback', 'function' )

        CommandManager.commands[params.name:lower()] = {
            name = params.name,
            args = params.args,
            description = params.description,
            localPlayerOnly = params.localPlayerOnly,
            friendsOnly = params.friendsOnly,
            callback = params.callback,
        }
    end,
    subPrefix = function( text )
        local usedPrefix = nil

        for _, prefix in ipairs( CommandManager.prefixes ) do
            if string.StartsWith( text, prefix ) then
                usedPrefix = prefix
                break
            end
        end

        if usedPrefix then
            return string.TrimLeft( string.sub( text, #usedPrefix + 1 ) )
        end
    end,
    parseArgs = function( stringArgs )
        local args = string.Explode( '%s+', stringArgs, true )
        local cmd = table.remove( args, 1 ):lower()

        if cmd != CommandManager.prefixKeyword then
            return
        end

        cmd = table.remove( args, 1 ):lower()

        local i = 1
        while i <= #args do
            local quote = nil

            if string.StartsWith( args[i], [["]] ) then
                quote = [["]]
            elseif string.StartsWith( args[i], [[']] ) then
                quote = [[']]
            end

            if quote then
                local arg = {}
                local i2 = i
                while i2 <= #args do
                    table.insert( arg, args[i2] )

                    if string.EndsWith( args[i2], quote ) then
                        for j = i, i2 do
                            table.remove( args, i )
                        end

                        arg = table.concat( arg, ' ' )
                        table.insert( args, i, string.sub( arg, 2, #arg - 1 ) )

                        i = i2
                        break
                    end

                    i2 = i2 + 1
                end
            end

            i = i + 1
        end

        return cmd, args
    end,
    onMessage = function( ply, message, _, _, localChat )
        message = CommandManager.subPrefix( message )
        if !message then return end

        local cmd, args = CommandManager.parseArgs( message )
        local command = cmd and CommandManager.commands[cmd]

        if command then
            if command.localPlayerOnly and ply != LocalPlayer() then return end
            if command.friendsOnly and ply != LocalPlayer() and !ply:IsFriend( LocalPlayer() ) then return end

            local success, response = xpcall( command.callback, CommandManager.onError, unpack( args ) )

            if !success then
                ErrorNoHalt( response )
                response = 'Error executing command'
            end

            if response then
                if command.localPlayerOnly then
                    chat.AddText( string.format( "You executed '%s': %s", cmd, response ) )
                else
                    local SayFunction = localChat and SayLocal or Say
                    SayFunction( string.format( [[;"%s" executed '%s': %s]], ply:Name(), cmd, response ) )
                end
            else
                chat.AddText( string.format( "%s executed '%s'", ply:Name(), cmd ) )
            end
        end
    end,
    onError = function( error )
        return error
    end,
    initHooks = function()
        hook.Add( 'OnPlayerChat', 'AokiChatCommands', CommandManager.onMessage )
    end,
}

-- CommandManager.addCommand({
--     name = 'test',
--     args = '...any args',
--     description = 'arg tester',
--     callback = function( ... )
--         PrintTable({ ... })
--     end,
-- })

local function makeFunctionName( command )
    local permittedFor

    if command.localPlayerOnly then
        permittedFor = 'owner'
    elseif command.friendsOnly then
        permittedFor = 'friends'
    else
        permittedFor = 'all'
    end

    return "%s (%s)" % { command.name, permittedFor }
end

CommandManager.addCommand({
    name = 'help',
    args = '[commandName]',
    description = 'displays available commands or information about a command',
    callback = function( commandName )
        if !commandName then
            local commands = {}

            for _, command in pairs( CommandManager.commands ) do
                table.insert( commands, #commands, makeFunctionName( command ) )
            end

            return table.concat( commands, ', ' )
        end

        local command = CommandManager.commands[commandName:lower()]

        if command then
            local name = makeFunctionName( command )
            return string.format( '%s %s - %s', name, command.args, command.description )
        end

        return string.format( '"%s" command does not exist', commandName )
    end,
})

include( './color-utils.lua' )( CommandManager )
include( './text-utils.lua' )( CommandManager )
include( './find.lua' )( CommandManager )
include( './dnd.lua' )( CommandManager )
include( './include.lua' )( CommandManager )
include( './goto-and-siton.lua' )( CommandManager )
include( './apartment.lua' )( CommandManager )
include( './sit.lua' )( CommandManager )
include( './rewear.lua' )( CommandManager )

CommandManager.initHooks()