package main

import (
	"errors"
	"fmt"
	"os"
	"path/filepath"
	"strings"

	tea "github.com/charmbracelet/bubbletea"
)

type model struct {
	project  string
	todosDir string
	count    int
}

func newModel(project string) (model, error) {
	absolute, err := filepath.Abs(project)
	if err != nil {
		return model{}, fmt.Errorf("resolve project directory %q: %w", project, err)
	}
	info, err := os.Stat(absolute)
	if err != nil {
		return model{}, fmt.Errorf("project directory %q: %w", absolute, err)
	}
	if !info.IsDir() {
		return model{}, fmt.Errorf("project path %q is not a directory", absolute)
	}

	dir := filepath.Join(absolute, ".pi", "todos")
	entries, err := os.ReadDir(dir)
	if errors.Is(err, os.ErrNotExist) {
		return model{project: absolute, todosDir: dir}, nil
	}
	if err != nil {
		return model{}, fmt.Errorf("read todo directory %q: %w", dir, err)
	}
	count := 0
	for _, entry := range entries {
		if !entry.IsDir() && strings.HasSuffix(entry.Name(), ".md") {
			count++
		}
	}
	return model{project: absolute, todosDir: dir, count: count}, nil
}

func (m model) Init() tea.Cmd { return nil }

func (m model) Update(message tea.Msg) (tea.Model, tea.Cmd) {
	if key, ok := message.(tea.KeyMsg); ok {
		switch key.String() {
		case "q", "ctrl+c":
			return m, tea.Quit
		}
	}
	return m, nil
}

func (m model) View() string {
	var state string
	if m.count == 0 {
		state = "No todos yet. Pi stores todo items in this directory."
	} else {
		state = fmt.Sprintf("Found %d todo file(s). Browsing is coming in the next ticket.", m.count)
	}
	return fmt.Sprintf("TodoApp\n\nProject: %s\nTodos:   %s\n\n%s\n\nPress q or Ctrl+C to quit.\n", m.project, m.todosDir, state)
}