// package hlcl contains logic for interacting with the
// herbstclient
package hlcl

import (
	"bytes"
	"fmt"
	"io"
	"os/exec"
	"strconv"
	"strings"

	"sectorinf.com/emilis/hlctl/ctllog"
	"sectorinf.com/emilis/hlctl/hlcl/cmd"
)

var log = ctllog.Logger{}.New("hlcl", ctllog.Purple)

func runGeneric(command string, stdin string, args ...string) (string, error) {
	cmd := exec.Command(command, args...)
	log.Printf("Running command [%s] with args: %v", command, args)
	var stdout, stderr = bytes.Buffer{}, bytes.Buffer{}
	cmd.Stderr = &stderr
	cmd.Stdout = &stdout
	if stdin != "" {
		pipe, err := cmd.StdinPipe()
		if err != nil {
			return "", fmt.Errorf("stdin pipe: %w", err)
		}
		if err := cmd.Start(); err != nil {
			return "", fmt.Errorf("start: %w", err)
		}
		io.WriteString(pipe, stdin+"\n")
		_, err = pipe.Write([]byte(stdin))
		if err != nil {
			return "", fmt.Errorf("write stdin: %w", err)
		}
		pipe.Close()
	} else {
		if err := cmd.Start(); err != nil {
			return "", fmt.Errorf("start: %w", err)
		}
	}
	if err := cmd.Wait(); err != nil {
		status, ok := err.(*exec.ExitError)
		if !ok {
			return "", fmt.Errorf("%s exec error: %w", command, err)
		}
		exitCode := status.ExitCode()
		return "", fmt.Errorf(
			"%s error (%d): %s",
			command,
			exitCode,
			strings.TrimSpace(stderr.String()),
		)
	}

	return strings.TrimSpace(stdout.String()), nil
}

func run(command cmd.Command, args ...string) (string, error) {
	args = append([]string{command.String()}, args...)
	return runGeneric("herbstclient", "", args...)
}

// query executes a command and pretty formats and error message
// based on the command's Pretty(), and returns the output
func query(c cmd.Command, args ...string) (string, error) {
	value, err := run(c, args...)
	if err != nil {
		return value, fmt.Errorf(
			"%s(%s): %w",
			c.Pretty(),
			strings.Join(args, ", "),
			err,
		)
	}
	return value, nil
}

// execute: wrapper for [query], discarding the stdout result
func execute(c cmd.Command, args ...string) error {
	_, err := query(c, args...)
	return err
}

func NewAttr(path string, value string, aType cmd.AttributeType) error {
	return execute(cmd.NewAttr, aType.String(), path, value)
}

func SetAttr(path string, value string) error {
	return execute(cmd.SetAttr, path, value)
}

func GetAttr(path string) (string, error) {
	return query(cmd.GetAttr, path)
}

func AttrType(path string) (string, error) {
	return query(cmd.AttrType, path)
}

func KeyUnbind() error {
	return execute(cmd.Keyunbind, "--all")
}

func MouseUnbind() error {
	return execute(cmd.Mouseunbind, "--all")
}

func ListMonitors() ([]Screen, error) {
	out, err := query(cmd.ListMonitors)
	if err != nil {
		return nil, err
	}
	outs := strings.Split(out, "\n")
	scrs := make([]Screen, len(outs))
	for i, line := range outs {
		scrs[i] = Screen{}.FromString(line)
	}
	return scrs, nil
}

func bindCMD(
	bindCommand cmd.Command,
	keys []string,
	command cmd.Command,
	args ...string,
) error {
	bindKeys := strings.Join(keys, "-")
	args = append([]string{bindKeys, command.String()}, args...)
	return execute(bindCommand, args...)
}

func Keybind(keys []string, command cmd.Command, args ...string) error {
	return bindCMD(cmd.Keybind, keys, command, args...)
}

func Mousebind(keys []string, command cmd.Command, args ...string) error {
	return bindCMD(cmd.Mousebind, keys, command, args...)
}

func Set(name, value string) error {
	return execute(cmd.Set, name, value)
}

func UseIndex(index uint8) error {
	return execute(cmd.UseIndex, strconv.Itoa(int(index)))
}

func MergeTag(name string) error {
	return execute(cmd.MergeTag, name)
}

func MoveIndex(index uint8) error {
	return execute(cmd.MoveIndex, strconv.Itoa(int(index)))
}

func TextWidth(font, message string) (string, error) {
	return runGeneric("textwidth", "", font, message)
}

func Rule(name string, args ...string) error {
	return execute(cmd.Rule, append([]string{name}, args...)...)
}

func Unrule() error {
	return execute(cmd.Unrule, "-F")
}

func SilentSpawn(command string, args ...string) error {
	return execute(cmd.Spawn, append([]string{command}, args...)...)
}

func Lock() error {
	return execute(cmd.Lock)
}

func Unlock() error {
	return execute(cmd.Unlock)
}

func AddTag(name string) error {
	return execute(cmd.AddTag, name)
}

func Dzen2(message string, args ...string) error {
	_, err := runGeneric("dzen2", message, args...)
	return err
}