package widgets

import (
	"errors"
	"fmt"
	"net"
	"net/url"
	"os"
	"os/exec"
	"path"
	"strconv"
	"strings"
	"time"

	"github.com/gdamore/tcell"
	"github.com/go-ini/ini"
	"github.com/kyoh86/xdg"

	"git.sr.ht/~sircmpwn/aerc/config"
	"git.sr.ht/~sircmpwn/aerc/lib/ui"
)

const (
	CONFIGURE_BASICS   = iota
	CONFIGURE_INCOMING = iota
	CONFIGURE_OUTGOING = iota
	CONFIGURE_COMPLETE = iota
)

const (
	IMAP_OVER_TLS = iota
	IMAP_STARTTLS = iota
	IMAP_INSECURE = iota
)

const (
	SMTP_OVER_TLS = iota
	SMTP_STARTTLS = iota
	SMTP_INSECURE = iota
)

type AccountWizard struct {
	ui.Invalidatable
	aerc      *Aerc
	conf      *config.AercConfig
	step      int
	steps     []*ui.Grid
	focus     int
	temporary bool
	testing   bool
	// CONFIGURE_BASICS
	accountName *ui.TextInput
	email       *ui.TextInput
	fullName    *ui.TextInput
	basics      []ui.Interactive
	// CONFIGURE_INCOMING
	imapUsername *ui.TextInput
	imapPassword *ui.TextInput
	imapServer   *ui.TextInput
	imapMode     int
	imapStr      *ui.Text
	imapUrl      url.URL
	incoming     []ui.Interactive
	// CONFIGURE_OUTGOING
	smtpUsername *ui.TextInput
	smtpPassword *ui.TextInput
	smtpServer   *ui.TextInput
	smtpMode     int
	smtpStr      *ui.Text
	smtpUrl      url.URL
	copySent     bool
	outgoing     []ui.Interactive
	// CONFIGURE_COMPLETE
	complete []ui.Interactive
}

func NewAccountWizard(conf *config.AercConfig, aerc *Aerc) *AccountWizard {
	wizard := &AccountWizard{
		accountName:  ui.NewTextInput("").Prompt("> "),
		aerc:         aerc,
		conf:         conf,
		temporary:    false,
		copySent:     true,
		email:        ui.NewTextInput("").Prompt("> "),
		fullName:     ui.NewTextInput("").Prompt("> "),
		imapPassword: ui.NewTextInput("").Prompt("] ").Password(true),
		imapServer:   ui.NewTextInput("").Prompt("> "),
		imapStr:      ui.NewText("imaps://"),
		imapUsername: ui.NewTextInput("").Prompt("> "),
		smtpPassword: ui.NewTextInput("").Prompt("] ").Password(true),
		smtpServer:   ui.NewTextInput("").Prompt("> "),
		smtpStr:      ui.NewText("smtps://"),
		smtpUsername: ui.NewTextInput("").Prompt("> "),
	}

	// Autofill some stuff for the user
	wizard.email.OnChange(func(_ *ui.TextInput) {
		value := wizard.email.String()
		wizard.imapUsername.Set(value)
		wizard.smtpUsername.Set(value)
		if strings.ContainsRune(value, '@') {
			server := value[strings.IndexRune(value, '@')+1:]
			wizard.imapServer.Set(server)
			wizard.smtpServer.Set(server)
		}
		wizard.imapUri()
		wizard.smtpUri()
	})
	wizard.imapServer.OnChange(func(_ *ui.TextInput) {
		imapServerURI := wizard.imapServer.String()
		smtpServerURI := imapServerURI
		if strings.HasPrefix(imapServerURI, "imap.") {
			smtpServerURI = strings.Replace(imapServerURI, "imap.", "smtp.", 1)
		}
		wizard.smtpServer.Set(smtpServerURI)
		wizard.imapUri()
		wizard.smtpUri()
	})
	wizard.imapUsername.OnChange(func(_ *ui.TextInput) {
		wizard.smtpUsername.Set(wizard.imapUsername.String())
		wizard.imapUri()
		wizard.smtpUri()
	})
	wizard.imapPassword.OnChange(func(_ *ui.TextInput) {
		wizard.smtpPassword.Set(wizard.imapPassword.String())
		wizard.imapUri()
		wizard.smtpUri()
	})
	wizard.smtpServer.OnChange(func(_ *ui.TextInput) {
		wizard.smtpUri()
	})
	wizard.smtpUsername.OnChange(func(_ *ui.TextInput) {
		wizard.smtpUri()
	})
	wizard.smtpPassword.OnChange(func(_ *ui.TextInput) {
		wizard.smtpUri()
	})

	basics := ui.NewGrid().Rows([]ui.GridSpec{
		{ui.SIZE_EXACT, 8}, // Introduction
		{ui.SIZE_EXACT, 1}, // Account name (label)
		{ui.SIZE_EXACT, 1}, // (input)
		{ui.SIZE_EXACT, 1}, // Padding
		{ui.SIZE_EXACT, 1}, // Full name (label)
		{ui.SIZE_EXACT, 1}, // (input)
		{ui.SIZE_EXACT, 1}, // Padding
		{ui.SIZE_EXACT, 1}, // Email address (label)
		{ui.SIZE_EXACT, 1}, // (input)
		{ui.SIZE_WEIGHT, 1},
	}).Columns([]ui.GridSpec{
		{ui.SIZE_WEIGHT, 1},
	})
	basics.AddChild(
		ui.NewText("\nWelcome to aerc! Let's configure your account.\n\n" +
			"This wizard supports basic I<style>pre { line-height: 125%; }
td.linenos .normal { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
span.linenos { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
td.linenos .special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
span.linenos.special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
.highlight .hll { background-color: #ffffcc }
.highlight .c { color: #888888 } /* Comment */
.highlight .err { color: #a61717; background-color: #e3d2d2 } /* Error */
.highlight .k { color: #008800; font-weight: bold } /* Keyword */
.highlight .ch { color: #888888 } /* Comment.Hashbang */
.highlight .cm { color: #888888 } /* Comment.Multiline */
.highlight .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */
.highlight .cpf { color: #888888 } /* Comment.PreprocFile */
.highlight .c1 { color: #888888 } /* Comment.Single */
.highlight .cs { color: #cc0000; font-weight: bold; background-color: #fff0f0 } /* Comment.Special */
.highlight .gd { color: #000000; background-color: #ffdddd } /* Generic.Deleted */
.highlight .ge { font-style: italic } /* Generic.Emph */
.highlight .ges { font-weight: bold; font-style: italic } /* Generic.EmphStrong */
.highlight .gr { color: #aa0000 } /* Generic.Error */
.highlight .gh { color: #333333 } /* Generic.Heading */
.highlight .gi { color: #000000; background-color: #ddffdd } /* Generic.Inserted */
.highlight .go { color: #888888 } /* Generic.Output */
.highlight .gp { color: #555555 } /* Generic.Prompt */
.highlight .gs { font-weight: bold } /* Generic.Strong */
.highlight .gu { color: #666666 } /* Generic.Subheading */
.highlight .gt { color: #aa0000 } /* Generic.Traceback */
.highlight .kc { color: #008800; font-weight: bold } /* Keyword.Constant */
.highlight .kd { color: #008800; font-weight: bold } /* Keyword.Declaration */
.highlight .kn { color: #008800; font-weight: bold } /* Keyword.Namespace */
.highlight .kp { color: #008800 } /* Keyword.Pseudo */
.highlight .kr { color: #008800; font-weight: bold } /* Keyword.Reserved */
.highlight .kt { color: #888888; font-weight: bold } /* Keyword.Type */
.highlight .m { color: #0000DD; font-weight: bold } /* Literal.Number */
.highlight .s { color: #dd2200; background-color: #fff0f0 } /* Literal.String */
.highlight .na { color: #336699 } /* Name.Attribute */
.highlight .nb { color: #003388 } /* Name.Builtin */
.highlight .nc { color: #bb0066; font-weight: bold } /* Name.Class */
.highlight .no { color: #003366; font-weight: bold } /* Name.Constant */
.highlight .nd { color: #555555 } /* Name.Decorator */
.highlight .ne { color: #bb0066; font-weight: bold } /* Name.Exception */
.highlight .nf { color: #0066bb; font-weight: bold } /* Name.Function */
.highlight .nl { color: #336699; font-style: italic } /* Name.Label */
.highlight .nn { color: #bb0066; font-weight: bold } /* Name.Namespace */
.highlight .py { color: #336699; font-weight: bold } /* Name.Property */
.highlight .nt { color: #bb0066; font-weight: bold } /* Name.Tag */
.highlight .nv { color: #336699 } /* Name.Variable */
.highlight .ow { color: #008800 } /* Operator.Word */
.highlight .w { color: #bbbbbb } /* Text.Whitespace */
.highlight .mb { color: #0000DD; font-weight: bold } /* Literal.Number.Bin */
.highlight .mf { color: #0000DD; font-weight: bold } /* Literal.Number.Float */
.highlight .mh { color: #0000DD; font-weight: bold } /* Literal.Number.Hex */
.highlight .mi { color: #0000DD; font-weight: bold } /* Literal.Number.Integer */
.highlight .mo { color: #0000DD; font-weight: bold } /* Literal.Number.Oct */
.highlight .sa { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Affix */
.highlight .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */
.highlight .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */
.highlight .dl { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Delimiter */
.highlight .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */
.highlight .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */
.highlight .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */
.highlight .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */
.highlight .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */
.highlight .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */
.highlight .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */
.highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */
.highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */
.highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */
.highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */
.highlight .vc { color: #336699 } /* Name.Variable.Class */
.highlight .vg { color: #dd7700 } /* Name.Variable.Global */
.highlight .vi { color: #3333bb } /* Name.Variable.Instance */
.highlight .vm { color: #336699 } /* Name.Variable.Magic */
.highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */</style><div class="highlight"><pre><span></span>Forwarded message from {{(index .OriginalFrom 0).Name}} on {{dateFormat .OriginalDate &quot;Mon Jan 2, 2006 at 3:04 PM&quot;}}:
{{wrapText .OriginalText 72}}
</pre></div>
</code></pre></div></td>
</tr>
</table>
</div> <!-- class=content -->
<div class='footer'>generated by <a href='https://git.causal.agency/cgit-pink/about/'>cgit-pink 1.4.1-2-gfad0</a> (<a href='https://git-scm.com/'>git 2.36.2.497.gbbea4dcf42</a>) at 2025-01-08 14:41:55 +0000</div>
</div> <!-- id=cgit -->
</body>
</html>
zard.advance)
	outgoing.AddChild(ui.NewFill(' ')).At(12, 0)
	outgoing.AddChild(wizard.smtpStr).At(13, 0)
	outgoing.AddChild(ui.NewFill(' ')).At(14, 0)
	outgoing.AddChild(
		ui.NewText("Copy sent messages to 'Sent' folder?").Bold(true)).
		At(15, 0)
	copySent := NewSelecter([]string{"Yes", "No"}, 0).
		Chooser(true).OnChoose(func(option string) {
		switch option {
		case "Yes":
			wizard.copySent = true
		case "No":
			wizard.copySent = false
		}
	})
	outgoing.AddChild(copySent).At(16, 0)
	outgoing.AddChild(selecter).At(17, 0)
	wizard.outgoing = []ui.Interactive{
		wizard.smtpUsername, wizard.smtpPassword, wizard.smtpServer,
		smtpMode, copySent, selecter,
	}
	outgoing.OnInvalidate(func(_ ui.Drawable) {
		wizard.Invalidate()
	})

	complete := ui.NewGrid().Rows([]ui.GridSpec{
		{ui.SIZE_EXACT, 7},  // Introduction
		{ui.SIZE_WEIGHT, 1}, // Previous / Finish / Finish & open tutorial
	}).Columns([]ui.GridSpec{
		{ui.SIZE_WEIGHT, 1},
	})
	complete.AddChild(ui.NewText(
		"\nConfiguration complete!\n\n" +
			"You can go back and double check your settings, or choose 'Finish' to\n" +
			"save your settings to accounts.conf.\n\n" +
			"To add another account in the future, run ':new-account'."))
	selecter = NewSelecter([]string{
		"Previous",
		"Finish & open tutorial",
		"Finish",
	}, 1).OnChoose(func(option string) {
		switch option {
		case "Previous":
			wizard.advance("Previous")
		case "Finish & open tutorial":
			wizard.finish(true)
		case "Finish":
			wizard.finish(false)
		}
	})
	complete.AddChild(selecter).At(1, 0)
	wizard.complete = []ui.Interactive{selecter}
	complete.OnInvalidate(func(_ ui.Drawable) {
		wizard.Invalidate()
	})

	wizard.steps = []*ui.Grid{basics, incoming, outgoing, complete}
	return wizard
}

func (wizard *AccountWizard) ConfigureTemporaryAccount(temporary bool) {
	wizard.temporary = temporary
}

func (wizard *AccountWizard) errorFor(d ui.Interactive, err error) {
	if d == nil {
		wizard.aerc.PushStatus(" "+err.Error(), 10*time.Second).
			Color(tcell.ColorDefault, tcell.ColorRed)
		wizard.Invalidate()
		return
	}
	for step, interactives := range [][]ui.Interactive{
		wizard.basics,
		wizard.incoming,
		wizard.outgoing,
	} {
		for focus, item := range interactives {
			if item == d {
				wizard.Focus(false)
				wizard.step = step
				wizard.focus = focus
				wizard.Focus(true)
				wizard.aerc.PushStatus(" "+err.Error(), 10*time.Second).
					Color(tcell.ColorDefault, tcell.ColorRed)
				wizard.Invalidate()
				return
			}
		}
	}
}

func (wizard *AccountWizard) finish(tutorial bool) {
	accountsConf := path.Join(xdg.ConfigHome(), "aerc", "accounts.conf")

	// Validation
	if wizard.accountName.String() == "" {
		wizard.errorFor(wizard.accountName,
			errors.New("Account name is required"))
		return
	}
	if wizard.email.String() == "" {
		wizard.errorFor(wizard.email,
			errors.New("Email address is required"))
		return
	}
	if wizard.fullName.String() == "" {
		wizard.errorFor(wizard.fullName,
			errors.New("Full name is required"))
		return
	}
	if wizard.imapServer.String() == "" {
		wizard.errorFor(wizard.imapServer,
			errors.New("IMAP server is required"))
		return
	}
	if wizard.imapServer.String() == "" {
		wizard.errorFor(wizard.smtpServer,
			errors.New("SMTP server is required"))
		return
	}

	file, err := ini.Load(accountsConf)
	if err != nil {
		file = ini.Empty()
	}

	var sec *ini.Section
	if sec, _ = file.GetSection(wizard.accountName.String()); sec != nil {
		wizard.errorFor(wizard.accountName,
			errors.New("An account by this name already exists"))
		return
	}
	sec, _ = file.NewSection(wizard.accountName.String())
	sec.NewKey("source", wizard.imapUrl.String())
	sec.NewKey("outgoing", wizard.smtpUrl.String())
	sec.NewKey("default", "INBOX")
	if wizard.smtpMode == SMTP_STARTTLS {
		sec.NewKey("smtp-starttls", "yes")
	}
	sec.NewKey("from", fmt.Sprintf("%s <%s>",
		wizard.fullName.String(), wizard.email.String()))
	if wizard.copySent {
		sec.NewKey("copy-to", "Sent")
	}

	if !wizard.temporary {
		f, err := os.OpenFile(accountsConf, os.O_WRONLY|os.O_CREATE, 0600)
		if err != nil {
			wizard.errorFor(nil, err)
			return
		}
		if _, err = file.WriteTo(f); err != nil {
			wizard.errorFor(nil, err)
			return
		}
	}

	account := config.AccountConfig{
		Name:     sec.Name(),
		Default:  "INBOX",
		From:     sec.Key("from").String(),
		Source:   sec.Key("source").String(),
		Outgoing: sec.Key("outgoing").String(),
	}
	if wizard.smtpMode == SMTP_STARTTLS {
		account.Params = map[string]string{
			"smtp-starttls": "yes",
		}
	}
	if wizard.copySent {
		account.CopyTo = "Sent"
	}
	wizard.conf.Accounts = append(wizard.conf.Accounts, account)

	view := NewAccountView(wizard.aerc, wizard.conf, &account,
		wizard.aerc.logger, wizard.aerc)
	wizard.aerc.accounts[account.Name] = view
	wizard.aerc.NewTab(view, account.Name)

	if tutorial {
		name := "aerc-tutorial"
		if _, err := os.Stat("./aerc-tutorial.7"); !os.IsNotExist(err) {
			// For development
			name = "./aerc-tutorial.7"
		}
		term, err := NewTerminal(exec.Command("man", name))
		if err != nil {
			wizard.errorFor(nil, err)
			return
		}
		wizard.aerc.NewTab(term, "Tutorial")
		term.OnClose = func(err error) {
			wizard.aerc.RemoveTab(term)
			if err != nil {
				wizard.aerc.PushStatus(" "+err.Error(), 10*time.Second).
					Color(tcell.ColorDefault, tcell.ColorRed)
			}
		}
	}

	wizard.aerc.RemoveTab(wizard)
}

func (wizard *AccountWizard) imapUri() url.URL {
	host := wizard.imapServer.String()
	user := wizard.imapUsername.String()
	pass := wizard.imapPassword.String()
	var scheme string
	switch wizard.imapMode {
	case IMAP_OVER_TLS:
		scheme = "imaps"
	case IMAP_STARTTLS:
		scheme = "imap"
	case IMAP_INSECURE:
		scheme = "imap+insecure"
	}
	var (
		userpass   *url.Userinfo
		userwopass *url.Userinfo
	)
	if pass == "" {
		userpass = url.User(user)
		userwopass = userpass
	} else {
		userpass = url.UserPassword(user, pass)
		userwopass = url.UserPassword(user, strings.Repeat("*", len(pass)))
	}
	uri := url.URL{
		Scheme: scheme,
		Host:   host,
		User:   userpass,
	}
	clean := url.URL{
		Scheme: scheme,
		Host:   host,
		User:   userwopass,
	}
	wizard.imapStr.Text("Connection URL: " +
		strings.ReplaceAll(clean.String(), "%2A", "*"))
	wizard.imapUrl = uri
	return uri
}

func (wizard *AccountWizard) smtpUri() url.URL {
	host := wizard.smtpServer.String()
	user := wizard.smtpUsername.String()
	pass := wizard.smtpPassword.String()
	var scheme string
	switch wizard.smtpMode {
	case SMTP_OVER_TLS:
		scheme = "smtps+plain"
	case SMTP_STARTTLS:
		scheme = "smtp+plain"
	case SMTP_INSECURE:
		scheme = "smtp+plain"
	}
	var (
		userpass   *url.Userinfo
		userwopass *url.Userinfo
	)
	if pass == "" {
		userpass = url.User(user)
		userwopass = userpass
	} else {
		userpass = url.UserPassword(user, pass)
		userwopass = url.UserPassword(user, strings.Repeat("*", len(pass)))
	}
	uri := url.URL{
		Scheme: scheme,
		Host:   host,
		User:   userpass,
	}
	clean := url.URL{
		Scheme: scheme,
		Host:   host,
		User:   userwopass,
	}
	wizard.smtpStr.Text("Connection URL: " +
		strings.ReplaceAll(clean.String(), "%2A", "*"))
	wizard.smtpUrl = uri
	return uri
}

func (wizard *AccountWizard) Invalidate() {
	wizard.DoInvalidate(wizard)
}

func (wizard *AccountWizard) Draw(ctx *ui.Context) {
	wizard.steps[wizard.step].Draw(ctx)
}

func (wizard *AccountWizard) getInteractive() []ui.Interactive {
	switch wizard.step {
	case CONFIGURE_BASICS:
		return wizard.basics
	case CONFIGURE_INCOMING:
		return wizard.incoming
	case CONFIGURE_OUTGOING:
		return wizard.outgoing
	case CONFIGURE_COMPLETE:
		return wizard.complete
	}
	return nil
}

func (wizard *AccountWizard) advance(direction string) {
	wizard.Focus(false)
	if direction == "Next" && wizard.step < len(wizard.steps)-1 {
		wizard.step++
	}
	if direction == "Previous" && wizard.step > 0 {
		wizard.step--
	}
	wizard.focus = 0
	wizard.Focus(true)
	wizard.Invalidate()
}

func (wizard *AccountWizard) Focus(focus bool) {
	if interactive := wizard.getInteractive(); interactive != nil {
		interactive[wizard.focus].Focus(focus)
	}
}

func (wizard *AccountWizard) Event(event tcell.Event) bool {
	interactive := wizard.getInteractive()
	switch event := event.(type) {
	case *tcell.EventKey:
		switch event.Key() {
		case tcell.KeyUp:
			fallthrough
		case tcell.KeyBacktab:
			fallthrough
		case tcell.KeyCtrlK:
			if interactive != nil {
				interactive[wizard.focus].Focus(false)
				wizard.focus--
				if wizard.focus < 0 {
					wizard.focus = len(interactive) - 1
				}
				interactive[wizard.focus].Focus(true)
			}
			wizard.Invalidate()
			return true
		case tcell.KeyDown:
			fallthrough
		case tcell.KeyTab:
			fallthrough
		case tcell.KeyCtrlJ:
			if interactive != nil {
				interactive[wizard.focus].Focus(false)
				wizard.focus++
				if wizard.focus >= len(interactive) {
					wizard.focus = 0
				}
				interactive[wizard.focus].Focus(true)
			}
			wizard.Invalidate()
			return true
		}
	}
	if interactive != nil {
		return interactive[wizard.focus].Event(event)
	}
	return false
}

func getSRV(host string, services []string) (string, string) {
	var hostport, srv string
	for _, srv = range services {
		_, addrs, err := net.LookupSRV(srv, "tcp", host)
		if err != nil {
			continue
		}
		if addrs[0].Target != "" && addrs[0].Port > 0 {
			hostport = net.JoinHostPort(
				strings.TrimSuffix(addrs[0].Target, "."),
				strconv.Itoa(int(addrs[0].Port)))
			break
		}
	}
	return hostport, srv
}