package tui

import (
	"fmt"
	"strconv"
	"strings"

	"github.com/charmbracelet/bubbles/textinput"
	tea "github.com/charmbracelet/bubbletea"

	"git.tukangketik.id/swanadiva/hostkeeper/internal/models"
)

type formMode int

const (
	formModeAdd formMode = iota
	formModeEdit
)

type fieldID int

const (
	fieldName fieldID = iota
	fieldHostname
	fieldPort
	fieldUsername
	fieldAuthType
	fieldPassword
	fieldGroup
	fieldTags
	fieldNotes
	fieldCount
)

var fieldLabels = map[fieldID]string{
	fieldName:     "Name",
	fieldHostname: "Hostname",
	fieldPort:     "Port",
	fieldUsername: "Username",
	fieldAuthType: "Auth Type",
	fieldPassword: "Password",
	fieldGroup:    "Group",
	fieldTags:     "Tags",
	fieldNotes:    "Notes",
}

// HostFormTab is a tab for adding/editing hosts
type HostFormTab struct {
	mode    formMode
	editing *models.Host
	dataDir string

	inputs  []textinput.Model
	focus   fieldID
	width   int
	height  int

	err        error
	saved      bool
}

// NewAddHostFormTab creates a new host add form tab
func NewAddHostFormTab(dataDir string) *HostFormTab {
	return newHostFormTab(formModeAdd, nil, dataDir)
}

// NewEditHostFormTab creates a new host edit form tab
func NewEditHostFormTab(host *models.Host, dataDir string) *HostFormTab {
	return newHostFormTab(formModeEdit, host, dataDir)
}

func newHostFormTab(mode formMode, host *models.Host, dataDir string) *HostFormTab {
	inputs := make([]textinput.Model, fieldCount)

	for i := range inputs {
		inputs[i] = textinput.New()
		inputs[i].Prompt = ""
	}

	inputs[fieldName].Placeholder = "My Server"
	inputs[fieldHostname].Placeholder = "192.168.1.1 or server.example.com"
	inputs[fieldPort].Placeholder = "22"
	inputs[fieldPort].SetValue("22")
	inputs[fieldUsername].Placeholder = "root"
	inputs[fieldAuthType].SetValue("password")
	inputs[fieldPassword].EchoMode = textinput.EchoPassword
	inputs[fieldPassword].Placeholder = "Enter password"
	inputs[fieldGroup].Placeholder = "production"
	inputs[fieldTags].Placeholder = "web,backend"
	inputs[fieldNotes].Placeholder = "Optional notes..."

	if mode == formModeEdit && host != nil {
		inputs[fieldName].SetValue(host.Name)
		inputs[fieldHostname].SetValue(host.Hostname)
		inputs[fieldPort].SetValue(strconv.Itoa(host.Port))
		inputs[fieldUsername].SetValue(host.Username)
		inputs[fieldAuthType].SetValue(host.Auth.Type)
		if host.Auth.Password != "" {
			inputs[fieldPassword].SetValue(host.Auth.Password)
		}
		inputs[fieldGroup].SetValue(host.Group)
		inputs[fieldTags].SetValue(strings.Join(host.Tags, ","))
		inputs[fieldNotes].SetValue(host.Notes)
	}

	inputs[fieldName].Focus()
	inputs[fieldName].Prompt = "> "

	return &HostFormTab{
		mode:    mode,
		editing: host,
		dataDir: dataDir,
		inputs:  inputs,
	}
}

func (t *HostFormTab) Name() string {
	if t.mode == formModeEdit {
		return "Edit: " + t.editing.Name
	}
	return "Add Host"
}

func (t *HostFormTab) Init() tea.Cmd {
	return textinput.Blink
}

func (t *HostFormTab) Update(msg tea.Msg) (Tab, tea.Cmd) {
	if t.saved {
		return t, nil
	}

	switch msg := msg.(type) {
	case tea.WindowSizeMsg:
		t.width = msg.Width
		t.height = msg.Height

	case tea.KeyMsg:
		switch msg.String() {
		case "esc":
			return t, func() tea.Msg { return closeFormMsg{} }

		case "enter":
			if t.focus == fieldAuthType {
				t.toggleAuthType()
				return t, nil
			}
			if t.focus == fieldCount-1 {
				return t.submit()
			}
			t.nextField()

		case " ", "left", "right":
			if t.focus == fieldAuthType {
				t.toggleAuthType()
				return t, nil
			}
			fallthrough

		case "tab", "down":
			t.nextField()

		case "shift+tab", "up":
			t.prevField()

		case "ctrl+s":
			return t.submit()

		default:
			if t.focus == fieldAuthType {
				// ignore typing on auth type field
				return t, nil
			}
			var cmd tea.Cmd
			t.inputs[t.focus], cmd = t.inputs[t.focus].Update(msg)
			return t, cmd
		}
	}

	return t, nil
}

func (t *HostFormTab) nextField() {
	t.inputs[t.focus].Blur()
	t.inputs[t.focus].Prompt = ""
	t.focus++
	if t.focus >= fieldCount {
		t.focus = fieldCount - 1
	}
	t.inputs[t.focus].Focus()
	t.inputs[t.focus].Prompt = "> "
}

func (t *HostFormTab) prevField() {
	t.inputs[t.focus].Blur()
	t.inputs[t.focus].Prompt = ""
	t.focus--
	if t.focus < 0 {
		t.focus = 0
	}
	t.inputs[t.focus].Focus()
	t.inputs[t.focus].Prompt = "> "
}

func cycleAuthType(current string) string {
	switch current {
	case "password":
		return "key"
	case "key":
		return "password"
	default:
		return "password"
	}
}

func (t *HostFormTab) toggleAuthType() {
	current := t.inputs[fieldAuthType].Value()
	t.inputs[fieldAuthType].SetValue(cycleAuthType(current))
}

func (t *HostFormTab) submit() (Tab, tea.Cmd) {
	name := t.inputs[fieldName].Value()
	hostname := t.inputs[fieldHostname].Value()
	username := t.inputs[fieldUsername].Value()

	if name == "" || hostname == "" || username == "" {
		t.err = fmt.Errorf("name, hostname, and username are required")
		return t, nil
	}

	port := 22
	if p := t.inputs[fieldPort].Value(); p != "" {
		if parsed, err := strconv.Atoi(p); err == nil && parsed > 0 {
			port = parsed
		}
	}

	authType := t.inputs[fieldAuthType].Value()
	if authType == "" {
		authType = "password"
	}

	var tags []string
	if tagStr := t.inputs[fieldTags].Value(); tagStr != "" {
		for _, tag := range strings.Split(tagStr, ",") {
			if trimmed := strings.TrimSpace(tag); trimmed != "" {
				tags = append(tags, trimmed)
			}
		}
	}

	var host *models.Host
	if t.mode == formModeEdit && t.editing != nil {
		host = t.editing
		host.Name = name
		host.Hostname = hostname
		host.Port = port
		host.Username = username
		host.Auth.Type = authType
		host.Auth.Password = t.inputs[fieldPassword].Value()
		host.Group = t.inputs[fieldGroup].Value()
		host.Tags = tags
		host.Notes = t.inputs[fieldNotes].Value()
	} else {
		host = &models.Host{
			Name:     name,
			Hostname: hostname,
			Port:     port,
			Username: username,
			Auth: models.AuthConfig{
				Type:     authType,
				Password: t.inputs[fieldPassword].Value(),
			},
			Group: t.inputs[fieldGroup].Value(),
			Tags:  tags,
			Notes: t.inputs[fieldNotes].Value(),
		}
	}

	t.saved = true
	return t, saveHostCmd(host, t.dataDir)
}

func (t *HostFormTab) View() string {
	var b strings.Builder

	title := "Add New Host"
	if t.mode == formModeEdit {
		title = "Edit Host"
	}
	b.WriteString(AppTitleStyle.Render(title))
	b.WriteString("\n\n")

	if t.err != nil {
		b.WriteString(ErrorStyle.Render(fmt.Sprintf("Error: %v", t.err)))
		b.WriteString("\n\n")
	}

	for i := fieldID(0); i < fieldCount; i++ {
		input := t.inputs[i]

		label := fieldLabels[i]
		style := SubtitleStyle
		if i == t.focus {
			style = HighlightStyle
		}
		b.WriteString(style.Render(label + ":"))
		b.WriteString("\n")

		if i == fieldAuthType {
			// Render auth type as toggle pills
			current := input.Value()
			pills := []string{"password", "key"}
			var parts []string
			for _, p := range pills {
				if p == current {
					if i == t.focus {
						parts = append(parts, SelectedStyle.Render(" "+p+" "))
					} else {
						parts = append(parts, TagStyle.Render(" "+p+" "))
					}
				} else {
					parts = append(parts, SubtitleStyle.Render(" "+p+" "))
				}
			}
			b.WriteString("  ")
			b.WriteString(strings.Join(parts, " "))
			b.WriteString("\n")
			if i == t.focus {
				b.WriteString(InfoStyle.Render("   Space/←/→ to toggle"))
			}
			b.WriteString("\n")
		} else {
			renderedInput := input.View()
			b.WriteString("  ")
			b.WriteString(renderedInput)
			b.WriteString("\n\n")
		}
	}

	// Help text
	b.WriteString(SubtitleStyle.Render(
		"↑↓: navigate  Enter: next  Ctrl+S: save  Esc: cancel"))

	return b.String()
}

func (t *HostFormTab) Close() {}