weather app for ComputerCraft

-- Function to parse JSON response
local function parseJson(jsonString)
    local obj = {}
    local stack = {}
    local curr = obj
    local key
    local inString = false
    local stringValue = ""

    for i = 1, #jsonString do
        local c = jsonString:sub(i, i)

        if c == "{" and not inString then
            local newTable = {}
            if key then
                curr[key] = newTable
                table.insert(stack, curr)
                curr = newTable
            else
                table.insert(stack, curr)
                curr = newTable
            end
            key = nil
        elseif c == "}" and not inString then
            curr = table.remove(stack)
        elseif c == "\"" then
            inString = not inString
        elseif c == ":" and not inString then
            key = stringValue
            stringValue = ""
        elseif c == "," and not inString then
            if key then
                curr[key] = stringValue
                key = nil
            else
                table.insert(curr, stringValue)
            end
            stringValue = ""
        else
            stringValue = stringValue .. c
        end
    end

    return obj
end
-- Function to URL encode a string
local function urlEncode(str)
    if str then
        str = string.gsub(str, "([^%w ])", function(c)
            return string.format("%%%02X", string.byte(c))
        end)
        str = string.gsub(str, " ", "+")
    end
    return str
end

-- Function to fetch weather data from the API
local function fetchWeatherData(city)
    local apiKey = "771196291bcb63791f108494bc9ce166"  -- Your API key here
    local encodedCity = urlEncode(city)
    local apiUrl = "http://api.openweathermap.org/data/2.5/weather?q=" .. encodedCity .. "&appid=" .. apiKey

    local response = ""
    local request = http.get(apiUrl)
    if request then
        response = request.readAll()
        request.close()
    else
        print("Failed to fetch weather data from the API")
    end

    return response
end


-- Function to display weather data
local function displayWeather(weatherData)
    if weatherData and weatherData.main then
        print("Weather Data:")
        print("City: " .. (weatherData.name or "Unknown"))
        print("Temperature: " .. (weatherData.main.temp and (weatherData.main.temp .. "°C") or "N/A"))
        print("Humidity: " .. (weatherData.main.humidity and (weatherData.main.humidity .. "%") or "N/A"))
        print("Wind Speed: " .. (weatherData.wind and weatherData.wind.speed and (weatherData.wind.speed .. " m/s") or "N/A"))
    else
        print("Failed to fetch weather data.")
    end
end

-- Main function
local function main()
    print("Enter a city name:")
    local city = read()
    local weatherDataResponse = fetchWeatherData(city)

    if not weatherDataResponse then
        return
    end

    local parsedData = parseJson(weatherDataResponse)
    displayWeather(parsedData)
end