local glyph
local color
local percent
local status

local warning_threshold = 20

local path = "/sys/class/power_supply/"
local batName

local function getBatName()
    local config = noctalia.getConfig("battery")

    if config == "bat0" then
        return "BAT0"
    elseif config == "custom" then
        return noctalia.getConfig("battery_name")
    end

    local folders = noctalia.listDir(path)

    if folders then
        for _, name in ipairs(folders) do
            if name:match("^BAT") then
                return name
            end
        end
    end
    return nil
end

local function getGlyph()
    if status == "Charging" then
        glyph = "battery-charging"
    elseif status == "Full" or status == "Not Charging" then
        glyph = "battery-plugged"
    elseif status == "Unknown" then
        glyph = "battery-exclamation"
    else
        glyph = percent >= 85 and "battery-4"
        or percent >= 55 and "battery-3"
        or percent >= 30 and "battery-2"
        or percent >= 10 and "battery-1"
        or "battery-0"
    end
end

local function getWarningThreshold()
    noctalia.runAsync(
        "grep warning_threshold ~/.local/state/noctalia/settings.toml | awk '{print $3}'",
        function(result)
            if result.exitCode ~= 0 then
                noctalia.log("battery-widget: failed to get warning_threshold: " .. result.stderr)
                return
            end

            local res = result.stdout

            if not warning_threshold then
                noctalia.log("battery-widget: invalid warning_threshold: " .. res)
                return
            end
            
            warning_threshold = tonumber(noctalia.string.trim(res))
        end
    )
end

local function getColor()
    if status ~= "Charging" and percent <= warning_threshold then
        color = noctalia.getConfig("warning_color")
        return
    end
    if status == "Charging" or status == "Full" or status == "Not Charging" then
        color = noctalia.getConfig("charging_color")
        return
    end
    color = noctalia.getConfig("color")
end

local function render()
    if (noctalia.getConfig("hide_plugged") and (status == "Charging" or status == "Not Charging"))
        or (noctalia.getConfig("hide_full") and status == "Full") then
        desktopWidget.render(ui.row())
        return
    end

    local content = {}
    if noctalia.getConfig("show_glyph") then
        table.insert(content, ui.glyph({ name = glyph, color = color }))
    end
    if noctalia.getConfig("show_label") then
        table.insert(content, ui.label({ text = percent .. "%", color = color }))
    end

    local vertical = noctalia.getConfig("layout") == "vertical"

    local layout = vertical and ui.column or ui.row

    desktopWidget.render(
        layout({
            gap = vertical and 0 or 4,
            align = "center"
        }, content)
    )
end

local function shellEscape(raw)
    return "'" .. raw:gsub("'", "'\\''") .. "'"
end

local function refreshBattery()
    noctalia.runAsync(
        "cat "
        .. shellEscape(path .. batName .. "/capacity")
        .. " "
        .. shellEscape(path .. batName .. "/status"),
        function(result)
            if result.exitCode ~= 0 then
                noctalia.log("battery-widget: failed to read battery: " .. result.stderr)
                return
            end

            local lines = {}
            for line in result.stdout:gmatch("[^\r\n]+") do
                table.insert(lines, line)
            end

            if not lines[1] or not lines[2] then
                noctalia.log("battery-widget: invalid battery output")
                return
            end

            percent = tonumber(noctalia.string.trim(lines[1]))
            status = noctalia.string.trim(lines[2])

            getGlyph()
            getColor()
            render()
        end
    )
end

batName = getBatName()
if not batName then
    noctalia.log("battery-widget: battery not found")
    return
end

getWarningThreshold()

function update()
    noctalia.setUpdateInterval(noctalia.getConfig("refresh_interval") * 1000)
    refreshBattery()
end