package jira

import (
	"bufio"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"os"
	"strconv"
	"strings"
	"time"

	"github.com/pkg/errors"

	"github.com/MichaelMure/git-bug/bridge/core"
	"github.com/MichaelMure/git-bug/input"
	"github.com/MichaelMure/git-bug/repository"
)

const (
	target             = "jira"
	keyServer          = "server"
	keyProject         = "project"
	keyCredentialsType = "credentials-type"
	keyCredentialsFile = "credentials-file"
	keyUsername        = "username"
	keyPassword        = "password"
	keyIDMap           = "bug-id-map"
	keyIDRevMap        = "bug-id-revmap"
	keyCreateDefaults  = "create-issue-defaults"
	keyCreateGitBug    = "create-issue-gitbug-id"

	defaultTimeout = 60 * time.Second
)

const moreConfigText = `
NOTE: There are a few optional configuration values that you can additionally
set in your git configuration to influence the behavior of the bridge. Please
see the notes at:
https://github.com/MichaelMure/git-bug/blob/master/doc/jira_bridge.md
`

const credTypeText = `
JIRA has recently altered it's authentication strategies. Servers deployed
prior to October 1st 2019 must use "SESSION" authentication, whereby the REST
client logs in with an actual username and password, is assigned a session, and
passes the session cookie with each request. JIRA Cloud and servers deployed
after October 1st 2019 must use "TOKEN" authentication. You must create a user
API token and the client will provide this along with your username with each
request.

Which authentication mechanism should this bridge use?
[1]: SESSION
[2]: TOKEN
`
const credentialsText = `
How would you like to store your JIRA login credentials?
[1]: sidecar JSON file: Your credentials will be stored in a JSON sidecar next
     to your git config. Note that it will contain your JIRA password in clear
     text.
[2]: git-config: Your credentials will be stored in the git config. Note that
     it will contain your JIRA password in clear text.
[3]: username in config, askpass: Your username will be stored in the git
     config. We will ask you for your password each time you execute the bridge.
`

// Configure sets up the bridge configuration
func (g *Jira) Configure(
	repo repository.RepoCommon, params core.BridgeParams) (
	core.Configuration, error) {
	conf := make(core.Configuration)
	var err error
	var url string
	var project string
	var credentialsFile string
	var username string
	var password string
	var serverURL string

	if params.Token != "" || params.TokenStdin {
		return nil, fmt.Errorf(
			"JIRA session tokens are extremely short lived. We don't store them " +
				"in the configuration, so they are not valid for this bridge.")
	}

	if params.Owner != "" {
		return nil, fmt.Errorf("owner doesn't make sense for jira")
	}

	serverURL = params.URL
	if url == "" {
		// terminal prompt
		serverURL, err = prompt("JIRA server URL", "URL")
		if err != nil {
			return nil, err
		}
	}

	project = params.Project
	if project == "" {
		project, err = prompt("JIRA project key", "project")
		if err != nil {
			return nil, err
		}
	}

	credType, err := promptOptions(credTypeText, 1, 2)
	if err != nil {
		return nil, err
	}

	choice, err := promptOptions(credentialsText, 1, 3)
	if err != nil {
		return nil, err
	}

	if choice == 1 {
		credentialsFile, err = prompt("Credentials file path", "path")
		if err != nil {
			return nil, err
		}
	}

	username, err = prompt("JIRA username", "username")
	if err != nil {
		return nil, err
	}

	password, err = input.PromptPassword()
	if err != nil {
		return nil, err
	}

	jsonData, err := json.Marshal(
		&SessionQuery{Username: username, Password: password})
	if err != nil {
		return nil, err
	}

	conf[core.KeyTarget] = target
	conf[keyServer] = serverURL
	conf[keyProject] = project

	switch credType {
	case 1:
		conf[keyCredentialsType] = "SESSION"
	case 2:
		conf[keyCredentialsType] = "TOKEN"
	}

	switch choice {
	case 1:
		conf[keyCredentialsFile] = credentialsFile
		err = ioutil.WriteFile(credentialsFile, jsonData, 0644)
		if err != nil {
			return nil, errors.Wrap(
				err, fmt.Sprintf("Unable to write credentials to %s", credentialsFile))
		}
	case 2:
		conf[keyUsername] = username
		conf[keyPassword] = password
	case 3:
		conf[keyUsername] = username
	}

	err = g.ValidateConfig(conf)
	if err != nil {
		return nil, err
	}

	fmt.Printf("Attempting to login with credentials...\n")
	client := NewClient(serverURL, nil)
	err = client.Login(conf)
	if err != nil {
		return nil, err
	}

	// verify access to the project with credentials
	fmt.Printf("Checking project ...\n")
	_, err = client.GetProject(project)
	if err != nil {
		return nil, fmt.Errorf(
			"Project %s doesn't exist on %s, or authentication credentials for (%s)"+
				" are invalid",
			project, serverURL, username)
	}

	fmt.Print(moreConfigText)
	return conf, nil
}

// ValidateConfig returns true if all required keys are present
func (*Jira) ValidateConfig(conf core.Configuration) error {
	if v, ok := conf[core.KeyTarget]; !ok {
		return fmt.Errorf("missing %s key", core.KeyTarget)
	} else if v != target {
		return fmt.Errorf("unexpected target name: %v", v)
	}

	if _, ok := conf[keyProject]; !ok {
		return fmt.Errorf("missing %s key", keyProject)
	}

	return nil
}

func promptOptions(description string, minVal, maxVal int) (int, error) {
	fmt.Print(description)
	for {
		fmt.Print("Select option: ")

		line, err := bufio.NewReader(os.Stdin).ReadString('\n')
		fmt.Println()
		if err != nil {
			return -1, err
		}

		line = strings.TrimRight(line, "\n")

		index, err := strconv.Atoi(line)
		if err != nil {
			fmt.Println("invalid input")
			continue
		}
		if index < minVal || index > maxVal {
			fmt.Println("invalid choice")
			continue
		}

		return index, nil
	}
}

func prompt(description, name string) (string, error) {
	for {
		fmt.Printf("%s: ", description)

		line, err := bufio.NewReader(os.Stdin).ReadString('\n')
		if err != nil {
			return "", err
		}

		line = strings.TrimRight(line, "\n")
		if line == "" {
			fmt.Printf("%s is empty\n", name)
			continue
		}

		return line, nil
	}
}