package main

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

	"ketotrack/data"
	"ketotrack/model"
)

var recordsFilename string

func init() {
	// Get user's homeDir directory
	homeDir, err := os.UserHomeDir()
	if err != nil {
		fmt.Println("Error fetching user's home directory:", err)
		os.Exit(1)
	}

	// Define the path to the application data directory
	ketotrackDir := filepath.Join(homeDir, ".ketotrack")

	// Create the directory if it does not exist
	err = os.MkdirAll(ketotrackDir, 0770)
	if err != nil {
		fmt.Println("Error creating .ketotrack directory:", err)
		os.Exit(1)
	}

	// Set data file path for readings
	recordsFilename = filepath.Join(ketotrackDir, "records.json")
}

func main() {
	var appCtx data.AppContext

	if err := appCtx.LoadRecords(recordsFilename); err != nil {
		fmt.Printf("Error loading records from file: %s\n", err)
	}

	for {
		choice, err := getUserInput("1. Enter new reading\n2. Enter new note\n3. Exit\nYour choice")
		if err != nil {
			fmt.Printf("Error reading choice: %s\n", err)
			continue
		}

		if choice == "3" {
			fmt.Println("Exiting...")
			break
		}

		switch choice {
		case "1":
			// Get a new Reading from the user
			reading, err := getReading()
			if err != nil {
				fmt.Printf("Error getting reading: %s\n", err)
			} else {
				appCtx.AddReading(reading)
			}
		case "2":
			// Get a new Note from the user
			note, err := getNote()
			if err != nil {
				fmt.Printf("Error getting note: %s\n", err)
			} else {
				appCtx.AddNote(note)
			}
		default:
			fmt.Printf("Invalid choice, please try again.\n\n")
		}
	}

	// Save Records before exiting
	if err := appCtx.SaveRecords(recordsFilename); err != nil {
		fmt.Printf("Error saving records to file: %s\n", err)
	}
}

func getNote() (model.Note, error) {
	text, err := getUserInput("Enter note text")
	if err != nil {
		return model.Note{}, err
	}
	return model.NewNote(text), nil
}

func getReading() (model.Reading, error) {
	// Get glucose reading
	glucose, err := getUserFloat("Enter glucose reading (mg/dL)")
	if err != nil {
		return model.Reading{}, fmt.Errorf("error getting glucose reading: %w", err)
	}

	// Validate glucose reading
	if glucose <= 0 {
		return model.Reading{}, errors.New("glucose reading cannot be less than or equal to 0")
	}

	// Get ketone reading
	ketone, err := getUserFloat("Enter ketone reading (mmol/L)")
	if err != nil {
		return model.Reading{}, fmt.Errorf("error getting ketone reading: %w", err)
	}

	// Validate ketone reading
	if ketone < 0 {
		fmt.Println("")
		return model.Reading{}, errors.New("ketone reading cannot be less than 0")
	}

	reading := model.NewReading(glucose, ketone)

	// Display GKI and level of ketosis
	fmt.Printf("\nYour GKI is: %0.2f\n", reading.GKI)
	switch {
	case reading.GKI <= 1:
		fmt.Println("You're in the highest level of ketosis.")
	case reading.GKI < 3:
		fmt.Println("You're in a high therapeutic level of ketosis.")
	case reading.GKI < 6:
		fmt.Println("You're in a moderate level of ketosis.")
	case reading.GKI <= 9:
		fmt.Println("You're in a low level of ketosis.")
	default:
		fmt.Println("You are not in ketosis.")
	}

	return reading, nil
}

func getUserInput(prompt string) (string, error) {
	fmt.Printf("%s: ", prompt)
	reader := bufio.NewReader(os.Stdin)
	input, err := reader.ReadString('\n')
	if err != nil {
		return "", err
	}
	return strings.TrimSpace(input), nil
}

func getUserFloat(prompt string) (float64, error) {
	// Get input as a string
	s, err := getUserInput(prompt)
	if err != nil {
		return 0, err
	}

	// Convert string to float
	f, err := strconv.ParseFloat(s, 64)
	if err != nil {
		return 0, err
	}
	return f, nil
}