package rank

import (
	"bytes"
	"cmp"
	"encoding/json"
	"errors"
	"fmt"
	"os"
	"slices"
	"strconv"
	"strings"
	"text/template"

	"git.andreafazzi.eu/andrea/probo/pkg/models"
	"git.andreafazzi.eu/andrea/probo/pkg/store/file"
	"github.com/alecthomas/chroma/quick"

	"github.com/charmbracelet/bubbles/key"
	"github.com/charmbracelet/bubbles/spinner"
	btTable "github.com/charmbracelet/bubbles/table"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/glamour"
	"github.com/charmbracelet/lipgloss"
	"github.com/d5/tengo/v2"
	"github.com/d5/tengo/v2/stdlib"
	foam "github.com/remogatto/sugarfoam"
	"github.com/remogatto/sugarfoam/components/group"
	"github.com/remogatto/sugarfoam/components/header"
	"github.com/remogatto/sugarfoam/components/help"
	"github.com/remogatto/sugarfoam/components/statusbar"
	"github.com/remogatto/sugarfoam/components/table"
	"github.com/remogatto/sugarfoam/components/viewport"
	"github.com/remogatto/sugarfoam/layout"
	"github.com/remogatto/sugarfoam/layout/tiled"
)

var responseTmpl = `
{{range $answer := .Answers}}
{{$answer.Quiz|toMarkdown $.Width}}
  R: {{$answer|toLipgloss}}
{{end}}
`

type ParticipantScore struct {
	Participant *models.Participant `json:"participant"`
	Response    *models.Response    `json:"response"`
	Score       int                 `json:"score"`
}

type Rank struct {
	Scores []*ParticipantScore `json:"scores"`
}

type RankModel struct {
	// UI
	viewport  *viewport.Model
	table     *table.Model
	group     *group.Model
	help      *help.Model
	statusBar *statusbar.Model
	spinner   spinner.Model

	// Layout
	document *layout.Layout

	// Key bindings
	bindings *keyBindings

	// json
	InputJson string
	Result    string

	// session
	rank *Rank

	// response
	responseTmpl *template.Template

	// filter file
	scriptFilePath string

	state int
}

func New(path string, stdin string) *RankModel {
	viewport := viewport.New()

	table := table.New(table.WithRelWidths(10, 20, 30, 30, 10))
	table.Model.SetColumns([]btTable.Column{
		{Title: "Pos", Width: 5},
		{Title: "Token", Width: 10},
		{Title: "Lastname", Width: 40},
		{Title: "Firstname", Width: 40},
		{Title: "Score", Width: 5},
	})

	group := group.New(
		group.WithItems(table, viewport),
		group.WithLayout(
			layout.New(
				layout.WithStyles(&layout.Styles{Container: lipgloss.NewStyle().Padding(1, 1)}),
				layout.WithItem(tiled.New(table, viewport)),
			),
		),
	)

	bindings := newBindings(group)
	statusBar := statusbar.New(bindings)

	s := spinner.New(
		spinner.WithStyle(
			lipgloss.NewStyle().Foreground(lipgloss.Color("265"))),
	)
	s.Spinner = spinner.Dot

	header := header.New(
		header.WithContent(
			lipgloss.NewStyle().
				Bold(true).
				Border(lipgloss.NormalBorder(), false, false, true, false).
				Render("😎 Rank 😎"),
		),
	)

	help := help.New(
		bindings,
		help.WithStyles(&foam.Styles{NoBorder: lipgloss.NewStyle().Padding(1, 1)}))

	document := layout.New(
		layout.WithStyles(&layout.Styles{Container: lipgloss.NewStyle().Margin(1)}),
		layout.WithItem(header),
		layout.WithItem(group),
		layout.WithItem(help),
		layout.WithItem(statusBar),
	)

	tmpl, err := template.New("response").
		Funcs(template.FuncMap{
			"toMarkdown": func(width int, quiz *models.Quiz) string {
				md, err := models.QuizToMarkdown(quiz)
				if err != nil {
					panic(err)
				}

				renderer, err := glamour.NewTermRenderer(
					glamour.WithStandardStyle("dracula"),
					glamour.WithWordWrap(width),
				)
				if err != nil {
					panic(err)
				}

				result, err := renderer.Render(md)
				if err != nil {
					panic(err)
				}

				return result
			},
			"toLipgloss": func(answer *models.ParticipantAnswer) string {
				color := "#ff0000"
				if answer.Correct {
					color = "#00ff00"
				}
				return lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color(color)).Render(answer.Answer.Text)
			},
		}).
		Parse(responseTmpl)
	if err != nil {
		panic(err)
	}

	return &RankModel{
		table:          table,
		viewport:       viewport,
		group:          group,
		statusBar:      statusBar,
		spinner:        s,
		document:       document,
		responseTmpl:   tmpl,
		bindings:       bindings,
		help:           help,
		scriptFilePath: path,
		InputJson:      stdin,
	}

}

func (m *RankModel) Init() tea.Cmd {
	var cmds []tea.Cmd

	cmds = append(cmds, m.group.Init(), m.executeScript(), m.spinner.Tick)

	m.group.Focus()

	return tea.Batch(cmds...)
}

func (m *RankModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	var cmds []tea.Cmd

	switch msg := msg.(type) {

	case tea.WindowSizeMsg:
		m.handleWindowSize(msg)

	case tea.KeyMsg:
		switch {
		case key.Matches(msg, m.bindings.quit):
			cmds = append(cmds, tea.Quit)
		}

	case scriptExecutedMsg:
		m.handleScriptExecuted(msg)

	case errorMsg:
		m.handleError(msg)
		m.state = ErrorState
	}

	cmds = m.handleState(msg, cmds)

	return m, tea.Batch(cmds...)
}

func (m *RankModel) View() string {
	return m.document.View()
}

func (m *RankModel) executeScript() tea.Cmd {
	return func() tea.Msg {
		if m.scriptFilePath == "" {
			return nil
		}

		rankJson, err := json.Marshal(Rank{Scores: make([]*ParticipantScore, 0)})
		if err != nil {
			panic(err)
		}

		script, err := os.ReadFile(m.scriptFilePath)
		if err != nil {
			panic(err)
		}

		s := tengo.NewScript(script)

		s.SetImports(stdlib.GetModuleMap("fmt", "json", "rand", "times"))
		_ = s.Add("input", m.InputJson)
		_ = s.Add("output", string(rankJson))

		c, err := s.Compile()
		if err != nil {
			panic(err)
		}

		if err := c.Run(); err != nil {
			panic(err)
		}

		return scriptExecutedMsg{fmt.Sprintf("%s", c.Get("output"))}

	}
}

func (m *RankModel) showErrorOnStatusBar(err error) {
	m.statusBar.SetContent(
		stateFormats[ErrorState][0],
		fmt.Sprintf(stateFormats[ErrorState][1], err),
		stateFormats[ErrorState][2],
	)
}

func (m *RankModel) updateTableContent() {
	rows := make([]btTable.Row, 0)

	for i, score := range m.rank.Scores {
		rows = append(rows, btTable.Row{
			strconv.Itoa(i + 1),
			score.Participant.Token,
			score.Participant.Lastname,
			score.Participant.Firstname,
			strconv.Itoa(score.Score),
		})

	}

	m.table.SetRows(rows)
}

func (m *RankModel) updateViewportContent() {
	if len(m.table.Rows()) == 0 {
		panic(errors.New("No scores available!"))
	}

	currentPos := m.table.SelectedRow()[0]

	pos, err := strconv.Atoi(currentPos)
	if err != nil {
		panic(err)
	}

	currentResponse := m.rank.Scores[pos-1]

	var buf bytes.Buffer

	var response struct {
		*models.Response
		Width int
	} = struct {
		*models.Response
		Width int
	}{currentResponse.Response, m.viewport.GetWidth()}

	err = m.responseTmpl.Execute(&buf, response)
	if err != nil {
		panic(err)
	}

	m.viewport.SetContent(sanitize(buf.String()))

}

func (m *RankModel) handleWindowSize(msg tea.WindowSizeMsg) {
	m.group.SetSize(msg.Width, msg.Height)
	m.document.SetSize(msg.Width, msg.Height)
}

func (m *RankModel) handleError(msg tea.Msg) {
	err := msg.(errorMsg)

	m.statusBar.SetContent(
		stateFormats[ErrorState][0],
		fmt.Sprintf(stateFormats[ErrorState][1], err.error),
		stateFormats[ErrorState][2],
	)
}

func (m *RankModel) handleScriptExecuted(msg tea.Msg) {
	rank := new(Rank)
	jsonData := []byte(msg.(scriptExecutedMsg).result)

	err := json.Unmarshal(jsonData, &rank)
	if err != nil {
		panic(err)
	}

	slices.SortFunc(rank.Scores,
		func(a, b *ParticipantScore) int {
			return cmp.Compare(b.Score, a.Score)
		})

	m.rank = rank

	m.updateTableContent()
	m.updateViewportContent()

	m.state = BrowseState
}

func (m *RankModel) handleState(msg tea.Msg, cmds []tea.Cmd) []tea.Cmd {
	_, cmd := m.group.Update(msg)

	if m.state == ExecutingScriptState {
		return m.updateSpinner(msg, cmd, cmds)
	}

	if m.state == BrowseState {
		m.updateViewportContent()
	}

	if m.state != ErrorState {
		m.statusBar.SetContent(
			stateFormats[BrowseState][0],
			fmt.Sprintf(stateFormats[BrowseState][1], len(m.rank.Scores)),
			stateFormats[BrowseState][2],
		)
	}

	cmds = append(cmds, cmd)

	return cmds
}

func (m *RankModel) updateSpinner(msg tea.Msg, cmd tea.Cmd, cmds []tea.Cmd) []tea.Cmd {
	m.spinner, cmd = m.spinner.Update(msg)

	m.statusBar.SetContent(fmt.Sprintf(stateFormats[m.state][0], m.spinner.View()), stateFormats[m.state][1], stateFormats[m.state][2])

	cmds = append(cmds, cmd)

	return cmds
}

func (m *RankModel) loadStore() tea.Cmd {
	return func() tea.Msg {
		sStore, err := file.NewDefaultSessionFileStore()
		if err != nil {
			panic(err)
		}

		return storeLoadedMsg{sStore}
	}
}

func toColoredJson(data []any) (string, error) {
	result, err := json.MarshalIndent(data, "", " ")
	if err != nil {
		return "", err
	}

	coloredBytes := make([]byte, 0)
	buffer := bytes.NewBuffer(coloredBytes)

	err = quick.Highlight(buffer, string(result), "json", "terminal16m", "dracula")
	if err != nil {
		panic(err)
	}

	return sanitize(buffer.String()), nil
}

func sanitize(text string) string {
	// FIXME: The use of a standard '-' character causes rendering
	// issues within the viewport. Further investigation is
	// required to resolve this problem.
	return strings.Replace(text, "-", "–", -1)
}

func desanitize(text string) string {
	// FIXME: The use of a standard '-' character causes rendering
	// issues within the viewport. Further investigation is
	// required to resolve this problem.
	return strings.Replace(text, "–", "-", -1)
}