package dirtoexcel

import (
	"fmt"
	"math"
	"os"
	"regexp"
	"strconv"
	"time"

	"github.com/lmittmann/tint"
	"github.com/spf13/cobra"
	"github.com/xuri/excelize/v2"
	"golang.org/x/exp/slog"
)

const re = `^(?P<company>[a-zA-Z0-9-]+)(?:_[a-zA-Z]+)?_(?P<value>\d+\.\d{1,2})`

func init() {
	slog.SetDefault(slog.New(tint.Options{
		Level:      slog.LevelDebug,
		TimeFormat: time.Kitchen,
	}.NewHandler(os.Stderr)))
}

func Run(cmd *cobra.Command, args []string) {
	outfile, err := cmd.Flags().GetString("out")
	if err != nil {
		slog.Error("failed to get outfile string", "error", err)
		os.Exit(1)
	}

	if outfile == "" {
		outfile = fmt.Sprintf("%d.xlsx", time.Now().Unix())
	}

	if err := Create(outfile, args[0]); err != nil {
		slog.Error("failed to create excel", "error", err)
		os.Exit(1)
	}
}

func Create(out, dir string) error {
	log := slog.With("dir", dir, "out", out)

	f := excelize.NewFile()
	defer func() {
		if err := f.Close(); err != nil {
			log.Error("failed to close excel file")
		}
	}()

	files, err := os.ReadDir(dir)
	if err != nil {
		return fmt.Errorf("failed to read dir: %w", err)
	}

	r, err := regexp.Compile(re)
	if err != nil {
		return fmt.Errorf("failed to compile regex: %w", err)
	}

	for i, j := range files {
		if j.IsDir() {
			continue
		}

		log.Info("found", "file", j.Name())

		res := r.FindAllStringSubmatch(j.Name(), -1)
		if res == nil {
			return fmt.Errorf("nothing found")
		}

		if len(res) != 1 || len(res[0]) != 3 {
			return fmt.Errorf("strange numbers of matches")
		}

		company := res[0][1]

		log.Debug("extracted", slog.String("company", company))

		if err := f.SetCellStr("Sheet1", fmt.Sprintf("A%d", i+1), company); err != nil {
			return fmt.Errorf("failed to set cell: %w", err)
		}

		value, err := strconv.ParseFloat(res[0][2], 32)
		if err != nil {
			return fmt.Errorf("failed to parse value: %w", err)
		}

		rValue := math.Round(value*100) / 100

		log.Debug("extracted", slog.Float64("value", rValue))

		if err := f.SetCellValue("Sheet1", fmt.Sprintf("B%d", i+1), rValue); err != nil {
			return fmt.Errorf("failed to set cell: %w", err)
		}

	}

	if err := f.SaveAs(out); err != nil {
		return fmt.Errorf("failed to save excel: %w", err)
	}

	log.Info("created excel")

	return nil
}