package main

import (
	"fmt"
	"regexp"
	"time"

	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
)

func (m model) Init() tea.Cmd {
	// Just return `nil`, which means "no I/O right now, please."
	return nil
}

func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	var cmd tea.Cmd

	if m.addTask {
		m.textinput, cmd = m.textinput.Update(msg)
	}
	
	switch msg := msg.(type) {

	// Is it a key press?
	case tea.KeyMsg:

		// Cool, what was the actual key pressed?
		switch msg.String() {

		// These keys should exit the program.
		case "ctrl+c", "q":
			return m, tea.Quit

		// The "up" and "k" keys move the cursor up
		case "up", "k":
			if m.cursor > 0 && !m.addTask {
				m.cursor--
			}

		// The "down" and "j" keys move the cursor down
		case "down", "j":
			if m.cursor < len(m.todos)-1 && !m.addTask {
				m.cursor++
			}

		case "left", "h":
			if m.tab > 0 && !m.addTask {
				m.tab--
			}

		case "right", "l":
			if m.tab < 4 && !m.addTask {
				m.tab++
			}

		// new task
		case "n":
			if !m.addTask {
				m.addTask = true
				m.textinput.Focus()
				m.textinput.Reset()
			}
		
		case "esc":
			if m.addTask {
				m.addTask = false
				m.textinput.Reset()
			}

		case "enter":
			if m.addTask {
				AddNewTask(&m)
				m.addTask = false
				m.textinput.Reset()
			}

		// The "enter" key and the spacebar (a literal space) toggle
		// the selected state for the item that the cursor is pointing at.
		case " ":

			if !m.addTask {
				if m.todos[m.cursor].done {
					m.todos[m.cursor].done = false
				} else {
					m.todos[m.cursor].done = true
				}
			}

		}
	}


	// Return the updated model to the Bubble Tea runtime for processing.
	// Note that we're not returning a command.
	return m, cmd
}

func AddNewTask(m *model) {
	taskTitle := m.textinput.Value()

	// parse date in title
	var doDate int64 = -1
	var deadline int64 = -1

    reDate := regexp.MustCompile("\\d{1,2}/\\d{1,2}")
    date := reDate.FindStringSubmatch(taskTitle)
	
	if len(date) > 0 {
		// what the fuck Go
		date, _ := time.Parse("02/01/2006", "10/03/2025")
		doDate = date.Unix()
		
	}

	t := todo{
		name: taskTitle,
		done: false,
		startdate: doDate,
		deadline: deadline,
		priority: 1,
		isInbox: true,
	}
	m.todos = append(m.todos, t)
}

func (m model) View() string {
	// The header
	s := ""
	currentList := []todo{}

	s += "GOTD\n\n"

	switch m.tab {
	case 0:
		// s += "Inbox"
		taskFilter := func(t todo) bool { return t.isInbox }
		currentList = filter(m.todos, taskFilter)
	case 1:
		// s += "Today"
		taskFilter := func(t todo) bool { return t.startdate == midnightToUnix() || t.deadline == midnightToUnix() }
		currentList = filter(m.todos, taskFilter)
	case 2:
		// s += "Tomorrow"
		// 86400 seconds in 24h, add it on to today's midnight for tomorrow's midnight
		taskFilter := func(t todo) bool { return t.startdate == midnightToUnix() + 86400 || t.deadline == midnightToUnix() + 86400}
		currentList = filter(m.todos, taskFilter)
	case 3:
		// s += "Scheduled"
		taskFilter := func(t todo) bool { return t.startdate != -1 }
		currentList = filter(m.todos, taskFilter)
	case 4:
		// s += "Anytime"
		taskFilter := func(t todo) bool { return t.startdate == -1 }
		currentList = filter(m.todos, taskFilter)
	}


	// Iterate over our choices
	for i, value := range currentList {

		// Is the cursor pointing at this choice?
		cursor := " " // no cursor
		if m.cursor == i {
			cursor = ">" // cursor!
		}

		// Is this choice selected?
		checked := " " // not selected
		// if _, ok := m.selected[i]; ok {
		// 	checked = "x" // selected!
		// }
		if value.done {
			checked = "x"
		}

		renderedTime := time.Unix(value.startdate, 0)

		// Render the row
		s += fmt.Sprintf("%s [%s] %s – %s\n", cursor, checked, value.name, renderedTime)
	}

	s += "\n\n"

	// render tab bar
	for i, v := range []string{"Inbox", "Today", "Tomorrow", "Scheduled", "Anytime"} {
		if i == m.tab {
			s += lipgloss.NewStyle().
			Bold(true).
			Underline(true).
			PaddingRight(3).
			Render(v)
		} else {
			s += lipgloss.NewStyle().
			PaddingRight(3).
			Render(v)
		}
	}

	// The footer
	s += "\nn: new"

	if m.addTask {
		s += ": "
		s += m.textinput.View()
	}

	s += "\nq: quit.\n"

	// Send the UI for rendering
	return s
}