// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
package curl

import (
	"io"
	"net/url"
	"os/exec"
	"runtime"

	"github.com/vespa-engine/vespa/client/go/internal/util"
)

type header struct {
	key   string
	value string
}

type Command struct {
	Path          string
	Method        string
	PrivateKey    string
	CaCertificate string
	Certificate   string
	bodyFile      string
	bodyInput     io.Reader
	url           *url.URL
	headers       []header
	rawArgs       []string
}

func (c *Command) GetUrlPrefix() string {
	return c.url.Scheme + "://" + c.url.Host
}

func (c *Command) WithBodyFile(fn string) {
	if c.bodyInput != nil {
		util.JustExitMsg("cannot use both WithBodyFile and WithBodyInput")
	}
	c.bodyFile = fn
}

func (c *Command) WithBodyInput(r io.Reader) {
	if c.bodyFile != "" {
		util.JustExitMsg("cannot use both WithBodyFile and WithBodyInput")
	}
	c.bodyInput = r
}

func (c *Command) Args() []string {
	var args []string
	if c.PrivateKey != "" {
		args = append(args, "--key", c.PrivateKey)
	}
	if c.Certificate != "" {
		args = append(args, "--cert", c.Certificate)
	}
	if c.CaCertificate != "" {
		args = append(args, "--cacert", c.CaCertificate)
	}
	if c.Method != "" {
		args = append(args, "-X", c.Method)
	}
	for _, header := range c.headers {
		args = append(args, "-H", header.key+": "+header.value)
	}
	if c.bodyFile != "" {
		args = append(args, "--data-binary", "@"+c.bodyFile)
	} else if c.bodyInput != nil {
		args = append(args, "--data-binary", "@-")
	}
	args = append(args, c.rawArgs...)
	args = append(args, c.url.String())
	return args
}

func (c *Command) String() string {
	args := []string{c.Path}
	args = append(args, c.Args()...)
	return util.ShellQuoteArgs(args...)
}

func (c *Command) Header(key, value string) {
	c.headers = append(c.headers, header{key: key, value: value})
}

func (c *Command) Param(key, value string) {
	query := c.url.Query()
	query.Set(key, value)
	c.url.RawQuery = query.Encode()
}

func (c *Command) Run(stdout, stderr io.Writer) error {
	cmd := exec.Command(c.Path, c.Args()...)
	cmd.Stdout = stdout
	cmd.Stderr = stderr
	cmd.Stdin = c.bodyInput
	if err := cmd.Start(); err != nil {
		return err
	}
	return cmd.Wait()
}

func Post(url string) (*Command, error) { return curl("POST", url) }

func Get(url string) (*Command, error) { return curl("", url) }

func RawArgs(url string, args ...string) (*Command, error) {
	c, err := curl("", url)
	if err != nil {
		return nil, err
	}
	c.rawArgs = args
	return c, nil
}

func curl(method, rawurl string) (*Command, error) {
	path := "curl"
	if runtime.GOOS == "windows" {
		path = "curl.exe"
	}
	realURL, err := url.Parse(rawurl)
	if err != nil {
		return nil, err
	}
	return &Command{
		Path:   path,
		Method: method,
		url:    realURL,
	}, nil
}