local wezterm = require 'wezterm'
local io = require 'io'
local os = require 'os'
local act = wezterm.action

local function setup()
    local function isViProcess(pane)
        local proc = pane:get_foreground_process_name()
        if (proc:find('vim') or proc:find('nvim')) then return true end
        return false
    end

    local function conditionalActivatePane(window, pane, pane_direction,
                                           vim_direction)
        if (isViProcess(pane)) then
            window:perform_action(act.Multiple {
                act.SendKey { key = 'w', mods = 'CTRL' },
                act.SendKey { key = vim_direction }
            }, pane)
        else
            window:perform_action(act.ActivatePaneDirection(pane_direction),
                pane)
        end
    end

    wezterm.on('ActivatePaneDirection-right', function(window, pane)
        conditionalActivatePane(window, pane, 'Right', 'l')
    end)
    wezterm.on('ActivatePaneDirection-left', function(window, pane)
        conditionalActivatePane(window, pane, 'Left', 'h')
    end)
    wezterm.on('ActivatePaneDirection-up', function(window, pane)
        conditionalActivatePane(window, pane, 'Up', 'k')
    end)
    wezterm.on('ActivatePaneDirection-down', function(window, pane)
        conditionalActivatePane(window, pane, 'Down', 'j')
    end)

    -- Retrieve the current scrollback text and send to editor
    wezterm.on('edit-scrollback', function(window, pane)
        local viewport_text = pane:get_lines_as_text(10000)

        -- Create a temporary file to pass to vim
        local name = os.tmpname()

        local f = io.open(name, 'w+')
        if f == nil then return false end
        f:write(viewport_text)
        f:flush()
        f:close()

        -- Open a new window running vim and tell it to open the file
        window:perform_action(act.SpawnCommandInNewTab {
            args = { (os.getenv('EDITOR') or 'vi'), name }
        }, pane)

        -- Wait time for vim to read the file before we remove it.
        wezterm.sleep_ms(1000)
        os.remove(name)
    end)
end

return { setup = setup }