/*
 fcgo.go: Fucho de Go

 Last Change: 2021-06-15 Tue 18:30:10.
*/
package main

/*
#cgo LDFLAGS: -L. -lxdwapi -static
##### C_SOURCE #####
*/
import "C"

import (
	_ "embed"

	"encoding/csv"
	"flag"
	"fmt"
	"io"
	"log"
	"os"
	"regexp"
	"sort"
	"strings"
	"time"

	"golang.org/x/text/encoding/japanese"
	"golang.org/x/text/transform"
)

//go:embed fcgo.go
var go_source string

type Data struct {
	Hno string
	Page string
}

func (d *Data) ToCsv() string {
	s := []string{d.Hno, d.Page}
	return strings.Join(s, ",")
}

var (
    ver = "0.2"

	dump bool
	pver bool
	clean bool
	skip bool
	all bool
	debug bool
	xdwfile string

	txtfile = "fctmp_txt.txt"
	infofile = "fctmp_info.csv"
	orderfile = "sort.list"	// input
	pagefile = "fctmp_page.txt"
	output = "output.xdw"
)

func init() {
	/* INITIALIZE FLAGS */
	flag.BoolVar(&pver, "v", false, "print version")
	flag.BoolVar(&dump, "s", false, "dump source")
	flag.BoolVar(&all, "a", false, "output all page (default: matched page)")
	flag.BoolVar(&clean, "c", false, "clean temporary files & exit")
	flag.BoolVar(&skip, "e", false, "use existed files")
	flag.BoolVar(&debug, "d", false, "debug mode")
	flag.StringVar(&xdwfile, "i", "fc.xdw", "target xdw file")
}

func main() {
	flag.Parse()
	if pver {
		fmt.Printf("fcgo [ver %s]\n", ver)
		os.Exit(0)
	}
	if dump {
		fmt.Println(go_source)
		os.Exit(0)
	}

    /* PRINT HEADER */
    fmt.Println("===================================================")
    fmt.Println(" 普徴のみならず納通なら被保番でソートできるかも... ")
    fmt.Printf("         - fcgo [ver %s] -\n", ver)
    fmt.Println("===================================================\n")
	print_time("now")
	fmt.Println("[0] start ...")

    /* CLEAN TEMPORARY DIRECTORY */
	os.Remove(output)
	if !skip {
		clean_full()
	}
	if clean {
		os.Exit(0)
	}
	print_time("check done")

	fmt.Println("[1] extract ...")
	if !skip {
		C.xdw2txt(C.CString(xdwfile), C.CString(txtfile))
	}
	print_time("extract done.")

	c := make(chan int)
	fmt.Println("[2] split ... (run background)")
	go func() {
		if !skip {
			C.xdwsplit1(C.CString(xdwfile))
		}
		print_time("split done.")
		c <- 1
	}()

	fmt.Println("[3] analize ...")
	data_hash, err := analize(txtfile, infofile)
	if err != nil {
		log.Fatal(err)
	}
	print_time("analize done.")
	debug_print(debug, fmt.Sprintf("len = %d", len(data_hash)))

	fmt.Println("[4] read order ...")
	h_order, n, err := read_order(orderfile)
	if err != nil {
		log.Fatal(err)
	}
	print_time("read order done.")
	debug_print(debug, fmt.Sprintf("len = %d / %d", len(h_order), n))

	fmt.Println("[5] make_list ...")
	n, err = make_list(h_order, data_hash, pagefile, all)
	if err != nil {
		log.Fatal(err)
	}
	print_time("make list done.")
	debug_print(debug, fmt.Sprintf("order = %d", n))

	<-c

	fmt.Println("[6] merge ...")
	clean_mini()
	C.xdwmerge(C.CString(pagefile), C.CString(output))
	print_time("merge done.")
	clean_mini()

	fmt.Println("[7] page ...")
	C.xdwaddpage(C.CString(output), C.int(1))
	print_time("page done.")

	if !debug {
		fmt.Println("[8] clean ...")
		clean_full()
		print_time("clean done.")
	}
}

func analize(txtfile, infofile string) (map[string]Data, error) {
	hash := make(map[string]Data)

	c, err := os.ReadFile(txtfile)
	if err != nil {
		return hash, err
	}
	r := strings.NewReader(string(c))
	tr := transform.NewReader(r, japanese.ShiftJIS.NewDecoder())
	b, err := io.ReadAll(tr)
	if err != nil {
		return hash, err
	}

	regHno := regexp.MustCompile(`0[1238]0[0-9]{7}`)

	var csv string

	buf := strings.Split(string(b), "期別保険料額")
	for p, v := range buf[:len(buf)-1] {
		s := zen2han(v)
		hno := regHno.FindString(s)
		page := fmt.Sprintf("%05d", p + 1)

		data := Data {
			Hno: hno,
			Page: page,
		}
		hash[hno] = data

		csv += data.ToCsv() + "\n"
	}

	if err := os.WriteFile(infofile, []byte(csv), 0644); err != nil {
		return hash, err
	}
	return hash, nil;
}

func zen2han(s string) (string) {
	s = strings.ReplaceAll(s, "０", "0")
	s = strings.ReplaceAll(s, "１", "1")
	s = strings.ReplaceAll(s, "２", "2")
	s = strings.ReplaceAll(s, "３", "3")
	s = strings.ReplaceAll(s, "４", "4")
	s = strings.ReplaceAll(s, "５", "5")
	s = strings.ReplaceAll(s, "６", "6")
	s = strings.ReplaceAll(s, "７", "7")
	s = strings.ReplaceAll(s, "８", "8")
	return strings.ReplaceAll(s, "９", "9")
}

func read_order(csvfile string) ([]string, int, error) {
	var order []string

	c, err := os.ReadFile(csvfile)
	if err != nil {
		return order, -1, err
	}
	r := strings.NewReader(string(c))
	tr := transform.NewReader(r, japanese.ShiftJIS.NewDecoder())
	b, err := io.ReadAll(tr)
	if err != nil {
		return order, -1, err
	}

	n := 0
	cr := csv.NewReader(strings.NewReader(string(b)))
	for {
		record, err := cr.Read()
		if err == io.EOF {
			break
		}
		if err != nil {
			return order, n, err
		}

		s := zen2han(record[0])
		if strings.HasPrefix(s, "0") {
			order = append(order, s)
		}
		n++
	}
	return order, n, nil
}

func make_list(h_order []string, hash map[string]Data, pagefile string, all bool) (int, error) {
	var n int
	var list []string
	done := make(map[string]bool)

	for _, h := range h_order {
		if _, ok := done[h]; !ok {
			if data, ok := hash[h]; ok {
				list = append(list, data.Page)
				done[h] = true
				n++
			}
		}
	}

	if all {
		var p []string
		for h, data := range hash {
			if !done[h] {
				p = append(p, data.Page)
			}
		}
		sort.Strings(p)
		list = append(list, p...)
	}

	if err := write_pagefile(pagefile, list); err != nil {
		return n, err
	}
	return n, nil
}

func write_pagefile(file string, list []string) error {
	f, err := os.OpenFile(file, os.O_RDWR|os.O_CREATE, 0755)
	if err != nil {
		return err
	}
	for _, p := range list {
		fmt.Fprintf(f, "fctmp_%s.xdw\n", p)
	}
	if err := f.Close(); err != nil {
		return err
	}
	return nil
}

func print_time(msg string) {
	now := time.Now()
	fmt.Printf("\t%v # %s\n", now, msg)
}

func debug_print(debug bool, msg string) {
	if debug {
		fmt.Printf("\t%s\n", msg)
	}
}

func clean_full() error {
	return clean_file("fctmp_")
}

func clean_mini() error {
	return clean_file("fctmp_b")
}

func clean_file(prefix string) error {
	files, err := os.ReadDir(".")
	if err != nil {
		return err
	}

	for _, file := range files {
		if strings.HasPrefix(file.Name(), prefix) {
			os.Remove(file.Name())
		}
	}
	return err
}