package adminui

import (
	"fmt"
	"strconv"
	"strings"

	tea "github.com/charmbracelet/bubbletea"
	"skyrama-tui/internal/db"
)

// ── Messages ──────────────────────────────────────────────────────────────────

type cntryLoadedMsg []db.AdminCountry
type cntryDoneMsg struct{ err error }

// ── Field indices ─────────────────────────────────────────────────────────────

const (
	cfName      = 0
	cfContinent = 1
	cfP1        = 2
	cfP2        = 3
	cfP3        = 4
)

var continentOptions = []string{
	"void", "Africa", "Antarctica", "Asia",
	"Europe", "North America", "Oceania", "South America",
}

// ── Model ─────────────────────────────────────────────────────────────────────

type countriesTab struct {
	client   *db.AdminClient
	items    []db.AdminCountry
	cursor   int
	inForm   bool
	isEdit   bool
	editID   uint16
	fields   []field
	focusIdx int
	status   string
	isErr    bool
	w, h     int
}

func newCountriesTab(client *db.AdminClient) *countriesTab {
	return &countriesTab{client: client}
}

func (t *countriesTab) InForm() bool { return t.inForm }
func (t *countriesTab) Init() tea.Cmd { return t.load() }

func (t *countriesTab) load() tea.Cmd {
	return func() tea.Msg {
		items, err := t.client.ListCountries()
		if err != nil {
			return cntryDoneMsg{err}
		}
		return cntryLoadedMsg(items)
	}
}

func (t *countriesTab) openForm() {
	t.fields = []field{
		newTextField("Name", "e.g. Turkey"),
		newEnumField("Continent", continentOptions),
		newTextField("Product 1 ID", "1"),
		newTextField("Product 2 ID", "2"),
		newTextField("Product 3 ID", "3"),
	}
	t.fields[cfName].input.Focus()
	t.focusIdx = cfName
	t.isEdit = false
	t.inForm = true
	t.status = ""
}

func (t *countriesTab) openEditForm(c db.AdminCountry) {
	t.fields = []field{
		prefill("Name", c.Name),
		newEnumField("Continent", continentOptions),
		prefill("Product 1 ID", strconv.Itoa(int(c.P1))),
		prefill("Product 2 ID", strconv.Itoa(int(c.P2))),
		prefill("Product 3 ID", strconv.Itoa(int(c.P3))),
	}
	setEnumSel(&t.fields[cfContinent], c.Continent)
	t.fields[cfName].input.Focus()
	t.focusIdx = cfName
	t.isEdit = true
	t.editID = c.ID
	t.inForm = true
	t.status = ""
}

func (t *countriesTab) submit() tea.Cmd {
	name := strings.TrimSpace(t.fields[cfName].value())
	continent := t.fields[cfContinent].value()
	p1s := strings.TrimSpace(t.fields[cfP1].value())
	p2s := strings.TrimSpace(t.fields[cfP2].value())
	p3s := strings.TrimSpace(t.fields[cfP3].value())

	if name == "" {
		t.status = "name is required"
		t.isErr = true
		return nil
	}
	p1, e1 := strconv.ParseUint(p1s, 10, 16)
	p2, e2 := strconv.ParseUint(p2s, 10, 16)
	p3, e3 := strconv.ParseUint(p3s, 10, 16)
	if e1 != nil || e2 != nil || e3 != nil {
		t.status = "product IDs must be valid numbers"
		t.isErr = true
		return nil
	}
	if t.isEdit {
		id := t.editID
		return func() tea.Msg {
			return cntryDoneMsg{t.client.UpdateCountry(id, name, continent, uint16(p1), uint16(p2), uint16(p3))}
		}
	}
	return func() tea.Msg {
		return cntryDoneMsg{t.client.AddCountry(name, continent, uint16(p1), uint16(p2), uint16(p3))}
	}
}

func (t *countriesTab) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch m := msg.(type) {
	case tea.WindowSizeMsg:
		t.w, t.h = m.Width, m.Height
		return t, nil

	case cntryLoadedMsg:
		t.items = []db.AdminCountry(m)
		if t.cursor >= len(t.items) && t.cursor > 0 {
			t.cursor = len(t.items) - 1
		}
		return t, nil

	case cntryDoneMsg:
		if m.err != nil {
			t.status = m.err.Error()
			t.isErr = true
			return t, nil
		}
		t.inForm = false
		t.status = "saved"
		t.isErr = false
		return t, t.load()

	case tea.KeyMsg:
		if t.inForm {
			switch m.String() {
			case "esc":
				t.inForm = false
				t.status = ""
			case "ctrl+s":
				return t, t.submit()
			default:
				var cmd tea.Cmd
				t.focusIdx, cmd = handleFormKey(t.fields, t.focusIdx, m)
				return t, cmd
			}
			return t, nil
		}
		switch m.String() {
		case "q":
			return t, tea.Quit
		case "j", "down":
			if t.cursor < len(t.items)-1 {
				t.cursor++
			}
		case "k", "up":
			if t.cursor > 0 {
				t.cursor--
			}
		case "a":
			t.openForm()
		case "e":
			if len(t.items) > 0 {
				t.openEditForm(t.items[t.cursor])
			}
		case "r":
			return t, t.load()
		}
	}
	return t, nil
}

func (t *countriesTab) View() string {
	var sb strings.Builder
	sb.WriteString(hdrSt.Render("  Countries") + "\n\n")

	if t.inForm {
		formTitle := "Add Country"
		if t.isEdit {
			formTitle = fmt.Sprintf("Edit Country #%d", t.editID)
		}
		sb.WriteString(titleSt.Render("  "+formTitle) + "\n\n")
		sb.WriteString(renderForm(t.fields, t.focusIdx))
		sb.WriteString("\n  " + renderStatus(t.status, t.isErr))
		sb.WriteString("\n\n  " + dimSt.Render(helpForm))
		return sb.String()
	}

	header := fmt.Sprintf("  %-5s  %-20s  %-14s  %s", "ID", "Name", "Continent", "Products (P1/P2/P3)")
	sb.WriteString(dimSt.Render(header) + "\n")
	sb.WriteString(dimSt.Render("  " + strings.Repeat("─", 60)) + "\n")

	if len(t.items) == 0 {
		sb.WriteString(dimSt.Render("  (no countries)") + "\n")
	}
	for i, c := range t.items {
		line := fmt.Sprintf("  %-5d  %-20s  %-14s  %d / %d / %d",
			c.ID, c.Name, c.Continent, c.P1, c.P2, c.P3)
		if i == t.cursor {
			sb.WriteString(cursorSt.Render("▸") + activeTS.Render(line[1:]) + "\n")
		} else {
			sb.WriteString(line + "\n")
		}
	}
	sb.WriteString("\n  " + renderStatus(t.status, t.isErr))
	sb.WriteString("\n\n  " + dimSt.Render("a:add  e:edit  j/k:nav  r:reload  q:quit"))
	return sb.String()
}