qmk-rgb/cmd/qmk-rgb-tool/output.go

package main

import (
	"fmt"
	"io"

	"github.com/spf13/cobra"
	"netdome.biz/paul/qmk-rgb/internal/device"
	intrgb "netdome.biz/paul/qmk-rgb/internal/rgb"
	"netdome.biz/paul/qmk-rgb/internal/via"
)

// The commands below print text, because that is what a person reads, and JSON
// only when it is asked for. The flag is persistent, so it reads the same
// everywhere: `qmk-rgb-tool --json info` and `qmk-rgb-tool info --json` are the
// same command. An agent that parses the output passes it; a person does not
// have to learn a second shape for the same information.
var jsonOutput bool

func addJSONFlag(cmd *cobra.Command) {
	cmd.PersistentFlags().BoolVar(&jsonOutput, "json", false, "Print JSON instead of text")
}

// printEffectListText writes one effect per line, its ID in brackets, under a
// heading per channel. The ID is in the line because it is what a user needs to
// check a name against the register, and what `mode <index>` takes.
func printEffectListText(out io.Writer, catalog *intrgb.Catalog, channels []via.Channel, display map[uint16]string, source string) error {
	for _, ch := range channels {
		effects := catalog.Effects(ch)
		if len(effects) == 0 {
			continue
		}
		fmt.Fprintf(out, "%s (%s)\n", channelName(ch, display), ch.Subsystem())
		for _, e := range effects {
			fmt.Fprintf(out, "  %s (%d)\n", e.Name, e.ID)
		}
	}
	if source != "" {
		fmt.Fprintf(out, "\nNames from %s\n", source)
	}
	return nil
}

// printZoneInfoText writes one line per zone, which is what a person compares.
func printZoneInfoText(out io.Writer, state infoOutput) error {
	fmt.Fprintf(out, "%s\n", state.Mode)
	for _, z := range state.Zones {
		enabled := "off"
		if z.Enabled {
			enabled = "on"
		}
		fmt.Fprintf(out, "  %-12s %-4s %-28s brightness %3d  speed %3d  color %s\n",
			z.Zone, enabled, z.Effect, z.Brightness, z.Speed, formatInfoColor(z.Color))
	}
	return nil
}

// formatInfoColor renders a hue and saturation the way the color command takes
// them, so a value read from the keyboard can be written back unchanged.
func formatInfoColor(c infoColor) string {
	return fmt.Sprintf("hsv:%d,%d", c.Hue, c.Saturation)
}

// printKeyboardInfoText writes one line per keyboard, with the index --device
// takes, because the index is the only part a user has to act on.
func printKeyboardInfoText(out io.Writer, devices []keyboardLine) error {
	if len(devices) == 0 {
		fmt.Fprintln(out, "No QMK keyboard found.")
		return nil
	}
	for _, d := range devices {
		known := ""
		if d.Known {
			known = " (known model)"
		}
		fmt.Fprintf(out, "%d  %s  0x%04X/0x%04X%s\n", d.Index, lineName(d), d.VendorID, d.ProductID, known)
	}
	return nil
}

// keyboardLine is one keyboard as the info command reports it. Its channels are
// deliberately absent: this command does not open the board, so it cannot know
// which ones it has, and reporting the ones a definition names would claim more
// than it knows.
type keyboardLine struct {
	Index     int    `json:"index"`
	Path      string `json:"path"`
	VendorID  uint16 `json:"vendorId"`
	ProductID uint16 `json:"productId"`
	Name      string `json:"name"`
	Known     bool   `json:"known"`
}

func lineName(d keyboardLine) string {
	if d.Name != "" {
		return d.Name
	}
	return "unknown model"
}

// describeDevices turns discovered devices into what the info command reports.
func describeDevices(devices []device.Device) []keyboardLine {
	lines := make([]keyboardLine, 0, len(devices))
	for _, d := range devices {
		lines = append(lines, keyboardLine{
			Index:     d.Index,
			Path:      d.Path,
			VendorID:  d.VendorID,
			ProductID: d.ProductID,
			Name:      lineName(keyboardLine{Name: d.Name}),
			Known:     d.Known,
		})
	}
	return lines
}