bpicode/fritzctl

package fritz

import (
    "fmt"

    "github.com/bpicode/fritzctl/httpread"
)

// ainBased API definition, guided by
// https://avm.de/fileadmin/user_upload/Global/Service/Schnittstellen/AHA-HTTP-Interface.pdf.
type ainBased interface {
    listDevices() (*Devicelist, error)
    switchOn(ain string) (string, error)
    switchOff(ain string) (string, error)
    toggle(ain string) (string, error)
    applyTemperature(value float64, ain string) (string, error)
}

// newAinBased creates a Fritz AHA API (working on AINs) from a given client.
func newAinBased(client *Client) ainBased {
    return &ainBasedClient{client: client}
}

type ainBasedClient struct {
    client *Client
}

// listDevices lists the basic data of the smart home devices.
func (a *ainBasedClient) listDevices() (*Devicelist, error) {
    url := a.homeAutoSwitch().
        query("switchcmd", "getdevicelistinfos").
        build()
    var deviceList Devicelist
    errRead := httpread.XML(a.client.getf(url), &deviceList)
    return &deviceList, errRead
}

// switchOn switches a device on. The device is identified by its AIN.
func (a *ainBasedClient) switchOn(ain string) (string, error) {
    return a.switchForAin(ain, "setswitchon")
}

// switchOff switches a device off. The device is identified by its AIN.
func (a *ainBasedClient) switchOff(ain string) (string, error) {
    return a.switchForAin(ain, "setswitchoff")
}

// toggle toggles the on/off state of a device. The device is identified by its AIN.
func (a *ainBasedClient) toggle(ain string) (string, error) {
    url := a.homeAutoSwitch().
        query("ain", ain).
        query("switchcmd", "setswitchtoggle").
        build()
    return httpread.String(a.client.getf(url))
}

// applyTemperature sets the desired temperature on a "HKR" device. The device is identified by its AIN.
func (a *ainBasedClient) applyTemperature(value float64, ain string) (string, error) {
    param, err := temperatureParam(value)
    if err != nil {
        return "", err
    }
    url := a.homeAutoSwitch().
        query("ain", ain).
        query("switchcmd", "sethkrtsoll").
        query("param", fmt.Sprintf("%d", param)).
        build()
    return httpread.String(a.client.getf(url))
}

func (a *ainBasedClient) switchForAin(ain, command string) (string, error) {
    url := a.homeAutoSwitch().
        query("ain", ain).
        query("switchcmd", command).
        build()
    return httpread.String(a.client.getf(url))
}

func (a *ainBasedClient) homeAutoSwitch() fritzURLBuilder {
    return a.client.query().path(homeAutomationURI)
}

func temperatureParam(t float64) (int64, error) {
    doubled := round(2 * t)
    regular := doubled >= 16 && doubled <= 56
    special := doubled == 253 || doubled == 254
    if !(regular || special) {
        return 0, fmt.Errorf("invalid temperature value: %.1f°C is not contained in the set of acceptable values: 8-28°C, 126.5, 127", t)
    }
    return doubled, nil
}

// round rounds a float64 value to an integer.
func round(v float64) int64 {
    return int64(v + 0.5)
}