package tui

import (
	"context"
	"fmt"
	"strings"

	tea "github.com/charmbracelet/bubbletea"
)

var nvidiaDCGMOptions = []struct {
	label   string
	level   int
	note    string
}{
	{"Level 1 — Quick", 1, "~1 min, configuration check"},
	{"Level 2 — Medium", 2, "~2 min, memory test"},
	{"Level 3 — Targeted stress", 3, "~10 min, SM + memory + PCIe [recommended]"},
	{"Level 4 — Extended stress", 4, "~30 min, extended burn-in"},
}

// enterNvidiaSATSetup resets and shows the DCGM level selection screen.
func (m model) enterNvidiaSATSetup() (tea.Model, tea.Cmd) {
	m.screen = screenNvidiaSATSetup
	m.nvidiaDurIdx = 2 // default: Level 3
	m.nvidiaSATCursor = 2
	m.busy = false
	return m, nil
}

// updateNvidiaSATSetup handles keys on the DCGM setup screen.
func (m model) updateNvidiaSATSetup(msg tea.KeyMsg) (tea.Model, tea.Cmd) {
	numOpts := len(nvidiaDCGMOptions)
	totalItems := numOpts + 2 // +2: Start, Cancel
	switch msg.String() {
	case "up", "k":
		if m.nvidiaSATCursor > 0 {
			m.nvidiaSATCursor--
		}
	case "down", "j":
		if m.nvidiaSATCursor < totalItems-1 {
			m.nvidiaSATCursor++
		}
	case " ", "enter":
		startIdx := numOpts
		cancelIdx := startIdx + 1
		switch {
		case m.nvidiaSATCursor < numOpts:
			m.nvidiaDurIdx = m.nvidiaSATCursor
		case m.nvidiaSATCursor == startIdx:
			return m.startNvidiaSAT()
		case m.nvidiaSATCursor == cancelIdx:
			m.screen = screenHealthCheck
			m.cursor = 0
		}
	case "esc":
		m.screen = screenHealthCheck
		m.cursor = 0
	case "ctrl+c", "q":
		return m, tea.Quit
	}
	return m, nil
}

// startNvidiaSAT launches the DCGM diagnostic.
func (m model) startNvidiaSAT() (tea.Model, tea.Cmd) {
	diagLevel := nvidiaDCGMOptions[m.nvidiaDurIdx].level

	ctx, cancel := context.WithCancel(context.Background())
	m.nvidiaSATCancel = cancel
	m.nvidiaSATAborted = false
	m.screen = screenNvidiaSATRunning
	m.nvidiaSATCursor = 0

	satCmd := func() tea.Msg {
		result, err := m.app.RunNvidiaAcceptancePackWithOptions(ctx, "", diagLevel, nil)
		return nvidiaSATDoneMsg{title: result.Title, body: result.Body, err: err}
	}

	return m, satCmd
}

// updateNvidiaSATRunning handles keys on the running screen.
func (m model) updateNvidiaSATRunning(msg tea.KeyMsg) (tea.Model, tea.Cmd) {
	switch msg.String() {
	case "a", "A":
		if m.nvidiaSATCancel != nil {
			m.nvidiaSATCancel()
			m.nvidiaSATCancel = nil
		}
		m.nvidiaSATAborted = true
		m.screen = screenHealthCheck
		m.cursor = 0
	case "ctrl+c":
		return m, tea.Quit
	}
	return m, nil
}

// renderNvidiaSATSetup renders the DCGM level selection screen.
func renderNvidiaSATSetup(m model) string {
	var b strings.Builder
	fmt.Fprintln(&b, "NVIDIA Diagnostics (DCGM)")
	fmt.Fprintln(&b)
	fmt.Fprintln(&b, "Diagnostic level:")
	for i, opt := range nvidiaDCGMOptions {
		radio := "( )"
		if i == m.nvidiaDurIdx {
			radio = "(*)"
		}
		prefix := "  "
		if m.nvidiaSATCursor == i {
			prefix = "> "
		}
		fmt.Fprintf(&b, "%s%s %s  (%s)\n", prefix, radio, opt.label, opt.note)
	}
	fmt.Fprintln(&b)
	startIdx := len(nvidiaDCGMOptions)
	startPfx := "  "
	cancelPfx := "  "
	if m.nvidiaSATCursor == startIdx {
		startPfx = "> "
	}
	if m.nvidiaSATCursor == startIdx+1 {
		cancelPfx = "> "
	}
	fmt.Fprintf(&b, "%sStart\n", startPfx)
	fmt.Fprintf(&b, "%sCancel\n", cancelPfx)
	fmt.Fprintln(&b)
	b.WriteString("[↑/↓] move  [space/enter] select  [esc] cancel\n")
	return b.String()
}

// renderNvidiaSATRunning renders the running screen.
func renderNvidiaSATRunning() string {
	return "NVIDIA Diagnostics (DCGM)\n\nTest is running...\n\n[a] Abort test  [ctrl+c] quit\n"
}