package main

import (
	"encoding/json"
	"flag"
	"fmt"
	"os"

	"go-faker/api"
	"go-faker/generator"
	"go-faker/types"
)

var (
	serverMode bool
	addr       string
	seed       string
	count      int
	dataType   string
	fieldsStr  string
)

func init() {
	flag.BoolVar(&serverMode, "server", false, "Run as HTTP API server")
	flag.StringVar(&addr, "addr", ":8080", "Server address")
	flag.StringVar(&seed, "seed", "default", "Random seed for reproducible data")
	flag.IntVar(&count, "count", 10, "Number of records to generate")
	flag.StringVar(&dataType, "type", "person", "Data type: person, address, product, analytics")
	flag.StringVar(&fieldsStr, "fields", "", "Comma-separated fields (empty = all)")
}

func main() {
	flag.Parse()

	if serverMode {
		server := api.NewServer(addr)
		if err := server.Start(); err != nil {
			fmt.Fprintf(os.Stderr, "Server error: %v\n", err)
			os.Exit(1)
		}
		return
	}

	dt := types.DataType(dataType)
	validFields, ok := types.ValidFields[dt]
	if !ok {
		fmt.Fprintf(os.Stderr, "Invalid type: %s. Valid types: person, address, product, analytics\n", dataType)
		os.Exit(1)
	}

	var fields []string
	if fieldsStr == "" {
		fields = validFields
	} else {
		fields = splitFields(fieldsStr)
	}

	faker := generator.New(seed)
	results := faker.GenerateBatch(count, dt, fields)

	enc := json.NewEncoder(os.Stdout)
	enc.SetIndent("", "  ")
	if err := enc.Encode(results); err != nil {
		fmt.Fprintf(os.Stderr, "JSON encode error: %v\n", err)
		os.Exit(1)
	}
}

func splitFields(s string) []string {
	var result []string
	start := 0
	for i := 0; i <= len(s); i++ {
		if i == len(s) || s[i] == ',' {
			if start < i {
				result = append(result, s[start:i])
			}
			start = i + 1
		}
	}
	return result
}