package plaintext

import (
	"bytes"
	"log"
	"net"
	"os"
	"path/filepath"

	"github.com/Loyalsoldier/geoip/lib"
)

var (
	defaultOutputDirForTextOut                  = filepath.Join("./", "output", "text")
	defaultOutputDirForClashRuleSetClassicalOut = filepath.Join("./", "output", "clash", "classical")
	defaultOutputDirForClashRuleSetIPCIDROut    = filepath.Join("./", "output", "clash", "ipcidr")
	defaultOutputDirForSurgeRuleSetOut          = filepath.Join("./", "output", "surge")
)

type text_out struct {
	Type        string
	Action      lib.Action
	Description string
	OutputDir   string
	OutputExt   string
	Want        []string
	Exclude     []string
	OnlyIPType  lib.IPType

	AddPrefixInLine string
	AddSuffixInLine string
}

func (t *text_out) marshalBytes(entry *lib.Entry) ([]byte, error) {
	entryCidr, err := entry.MarshalText(lib.GetIgnoreIPType(t.OnlyIPType))
	if err != nil {
		return nil, err
	}

	var buf bytes.Buffer
	switch t.Type {
	case TypeTextOut:
		err = t.marshalBytesForTextOut(&buf, entryCidr)
	case TypeClashRuleSetClassicalOut:
		err = t.marshalBytesForClashRuleSetClassicalOut(&buf, entryCidr)
	case TypeClashRuleSetIPCIDROut:
		err = t.marshalBytesForClashRuleSetIPCIDROut(&buf, entryCidr)
	case TypeSurgeRuleSetOut:
		err = t.marshalBytesForSurgeRuleSetOut(&buf, entryCidr)
	default:
		return nil, lib.ErrNotSupportedFormat
	}
	if err != nil {
		return nil, err
	}

	return buf.Bytes(), nil
}

func (t *text_out) marshalBytesForTextOut(buf *bytes.Buffer, entryCidr []string) error {
	for _, cidr := range entryCidr {
		if t.AddPrefixInLine != "" {
			buf.WriteString(t.AddPrefixInLine)
		}
		buf.WriteString(cidr)
		if t.AddSuffixInLine != "" {
			buf.WriteString(t.AddSuffixInLine)
		}
		buf.WriteString("\n")
	}
	return nil
}

func (t *text_out) marshalBytesForClashRuleSetClassicalOut(buf *bytes.Buffer, entryCidr []string) error {
	buf.WriteString("payload:\n")
	for _, cidr := range entryCidr {
		ip, _, err := net.ParseCIDR(cidr)
		if err != nil {
			return err
		}
		if ip.To4() != nil {
			buf.WriteString("  - IP-CIDR,")
		} else {
			buf.WriteString("  - IP-CIDR6,")
		}
		buf.WriteString(cidr)
		buf.WriteString("\n")
	}

	return nil
}

func (t *text_out) marshalBytesForClashRuleSetIPCIDROut(buf *bytes.Buffer, entryCidr []string) error {
	buf.WriteString("payload:\n")
	for _, cidr := range entryCidr {
		buf.WriteString("  - '")
		buf.WriteString(cidr)
		buf.WriteString("'\n")
	}

	return nil
}

func (t *text_out) marshalBytesForSurgeRuleSetOut(buf *bytes.Buffer, entryCidr []string) error {
	for _, cidr := range entryCidr {
		ip, _, err := net.ParseCIDR(cidr)
		if err != nil {
			return err
		}
		if ip.To4() != nil {
			buf.WriteString("IP-CIDR,")
		} else {
			buf.WriteString("IP-CIDR6,")
		}
		buf.WriteString(cidr)
		if t.AddSuffixInLine != "" {
			buf.WriteString(t.AddSuffixInLine)
		}
		buf.WriteString("\n")
	}

	return nil
}

func (t *text_out) writeFile(filename string, data []byte) error {
	if err := os.MkdirAll(t.OutputDir, 0755); err != nil {
		return err
	}

	if err := os.WriteFile(filepath.Join(t.OutputDir, filename), data, 0644); err != nil {
		return err
	}

	log.Printf("✅ [%s] %s --> %s", t.Type, filename, t.OutputDir)

	return nil
}