package main

import (
	_ "embed"
	"encoding/json"
	"flag"
	"fmt"
	"io"
	"os"
	"path/filepath"
	"strconv"
	"strings"

	"log/slog"

	"github.com/fatih/color"
)

var findAll = flag.Bool("all", false, "Find all occurrences")
var findType = flag.String("type", "string", "The type of value to find. Must be one of 'string' or 'number'")

type JSON = interface{}
type JSONObject = map[string]interface{}
type JSONArray = []interface{}

func init() {
	flag.Parse()
}

func main() {
	var inputData []byte

	if flag.NArg() == 1 || flag.Arg(1) == "-" {
		stdin, err := io.ReadAll(os.Stdin)
		if err != nil {
			panic(err)
		}

		inputData = stdin
	} else if flag.NArg() == 2 {
		file, err := os.ReadFile(flag.Arg(1))
		if err != nil {
			panic(err)
		}
		inputData = file
	} else {
		fmt.Printf("Usage: %s [-all] [-type=string|number] <match> [<file> | -]\n", filepath.Base(os.Args[0]))
		os.Exit(0)
	}

	data := make(JSONObject)
	json.Unmarshal(inputData, &data)
	switch *findType {
	case "string":
		// "EpToggle_PAYMENTINSURANCE_CAR_Description"
		findValue(data, flag.Arg(0))
	case "number":
		parsedNum, err := strconv.ParseFloat(flag.Arg(0), 64)
		if err != nil {
			panic(err)
		}
		findValue(data, parsedNum)
	}
}

func findValue[T comparable](haystack JSON, text T) {
	switch x := haystack.(type) {
	case JSONObject:
		findInObject(x, text, "")
	case JSONArray:
		findInList(x, text, "")
	default:
		slog.Error("JSON is not a nested structure.")
	}
}

func findInObject[T comparable](haystack JSONObject, value T, path string) {
	for k, v := range haystack {
		switch x := v.(type) {
		case string:
			if *findType != "string" {
				continue
			}
			if stringContains(x, value) {
				printPathAndMatch(path, x)
			}

		case float64:
			if *findType != "number" {
				continue
			}
			if floatEquals(x, value) {
				printPathAndMatch(path, x)
			}
		case JSONObject:
			findInObject(x, value, path+"."+k)
		case []interface{}:
			findInList(x, value, fmt.Sprintf("%s.%s", path, k))
		}
	}
}

func findInList[T comparable](list []interface{}, value T, path string) {
	for i, v := range list {
		switch x := v.(type) {
		case string:
			if *findType != "string" {
				continue
			}
			if stringContains(x, value) {
				printPathAndMatch(path, x)
			}

		case float64:
			if *findType != "number" {
				continue
			}
			if floatEquals(x, value) {
				printPathAndMatch(path, x)
			}

		case JSONObject:
			findInObject(x, value, fmt.Sprintf("%s[%d]", path, i))
		case []interface{}:
			findInList(x, value, fmt.Sprintf("%s[%d]", path, i))
		}
	}
}

func printPathAndMatch(path string, match interface{}) {
	if strings.HasPrefix(path, ".") {
		path = strings.Replace(path, ".", "", 1)
	}

	c := color.New(color.Bold)
	c.Printf("%s", path)
	fmt.Printf(":    ")
	c = color.New(color.FgHiBlack)
	c.Printf("%v\n", match)

	if !*findAll {
		os.Exit(0)
	}
}

func stringContains[T comparable](haystackString string, match T) bool {
	matchString, ok := any(match).(string)
	if !ok {
		return false
	}
	return strings.Contains(haystackString, matchString)
}

func floatEquals[T comparable](haystackFloat float64, match T) bool {
	matchFloat, ok := any(match).(float64)
	if !ok {
		return false
	}

	return haystackFloat == matchFloat
}