// Command pvfexport extracts an item_id -> display-name map from a DNF
// Script.pvf archive. It reads the stackable.lst and equipment.lst indexes,
// resolves each item file, and pulls the [name] section via ScriptMetadata.
//
// Usage:
//
//	pvfexport -pvf Script.pvf -out items.json
package main

import (
	"encoding/json"
	"flag"
	"fmt"
	"log"
	"os"
	"strconv"
	"strings"

	"pvfine/internal/pvf"
)

type itemEntry struct {
	ID    int64  `json:"id"`
	Name  string `json:"name"`
	Rarity int32 `json:"rarity"`
	Path  string `json:"path,omitempty"`
	Kind  string `json:"kind,omitempty"`
}

type exportResult struct {
	PVFPath string      `json:"pvf_path"`
	Total   int         `json:"total"`
	Items   []itemEntry `json:"items"`
}

func main() {
	pvfPath := flag.String("pvf", "Script.pvf", "path to Script.pvf")
	outPath := flag.String("out", "items.json", "output JSON path")
	compact := flag.Bool("compact", false, "输出紧凑的 {item_id: name} 映射（仅保留有名称的项）")
	flag.Parse()

	archive, err := pvf.Open(*pvfPath)
	if err != nil {
		log.Fatalf("打开 PVF 失败: %v", err)
	}
	defer archive.Release()

	items := make([]itemEntry, 0, 200000)
	seen := make(map[int64]bool)

	// 顺序处理两类物品列表，堆叠道具优先。
	for _, list := range []struct {
		root string
		path string
		kind string
	}{
		{"stackable", "stackable/stackable.lst", "stackable"},
		{"equipment", "equipment/equipment.lst", "equipment"},
	} {
		count, err := exportList(archive, list.root, list.path, list.kind, seen, &items)
		if err != nil {
			log.Printf("警告: 处理 %s 失败: %v", list.path, err)
			continue
		}
		log.Printf("%s: 解析 %d 条", list.path, count)
	}

	result := exportResult{
		PVFPath: *pvfPath,
		Total:   len(items),
		Items:   items,
	}

	var data []byte
	if *compact {
		// 紧凑映射：{item_id: name}，仅保留有名称的项
		compactMap := make(map[string]string, len(items))
		for _, it := range items {
			name := strings.TrimSpace(it.Name)
			if name != "" {
				compactMap[strconv.FormatInt(it.ID, 10)] = name
			}
		}
		data, err = json.Marshal(compactMap)
	} else {
		data, err = json.MarshalIndent(result, "", "  ")
	}
	if err != nil {
		log.Fatalf("序列化 JSON 失败: %v", err)
	}
	if err := os.WriteFile(*outPath, data, 0o644); err != nil {
		log.Fatalf("写入 %s 失败: %v", *outPath, err)
	}
	fmt.Printf("导出完成: %d 个物品 -> %s\n", len(items), *outPath)
}

func exportList(archive *pvf.Archive, root, listPath, kind string, seen map[int64]bool, items *[]itemEntry) (int, error) {
	idx, found := archive.Find(listPath)
	if !found {
		return 0, fmt.Errorf("未找到 %s", listPath)
	}
	text, err := archive.Text(idx)
	if err != nil {
		return 0, fmt.Errorf("读取 %s: %w", listPath, err)
	}
	pairs, err := pvf.ParseListText(text)
	if err != nil {
		return 0, fmt.Errorf("解析 %s: %w", listPath, err)
	}

	count := 0
	for _, pair := range pairs {
		id, err := strconv.ParseInt(strings.TrimSpace(pair.ID), 10, 64)
		if err != nil || id <= 0 {
			continue
		}
		if seen[id] {
			continue
		}
		path := cleanPath(pair.Path)
		itemIdx, ok := resolveItemFile(archive, root, path)
		if !ok {
			continue
		}
		meta, err := archive.ScriptMetadata(itemIdx)
		if err != nil {
			continue
		}
		seen[id] = true
		count++
		*items = append(*items, itemEntry{
			ID:     id,
			Name:   meta.Name,
			Rarity: meta.Rarity,
			Path:   path,
			Kind:   kind,
		})
	}
	return count, nil
}

// resolveItemFile 复刻服务端 readDungeonDropText 的候选路径策略：
// 先直接用 lst 里的路径，再尝试 root/ 前缀，最后尝试 (r) 修订文件名。
func resolveItemFile(archive *pvf.Archive, root, listedPath string) (int32, bool) {
	clean := cleanPath(listedPath)
	candidates := []string{clean}
	root = cleanPath(root)
	if root != "" && !strings.HasPrefix(strings.ToLower(clean), strings.ToLower(root)+"/") {
		candidates = append(candidates, root+"/"+clean)
	}
	for _, candidate := range append([]string(nil), candidates...) {
		dir, base := splitPath(candidate)
		if base == "" || strings.HasPrefix(strings.ToLower(base), "(r)") {
			continue
		}
		candidates = append(candidates, dir+"(r)"+base)
	}
	for _, candidate := range candidates {
		if idx, found := archive.Find(candidate); found {
			return idx, true
		}
	}
	return 0, false
}

func cleanPath(value string) string {
	value = strings.TrimSpace(strings.ReplaceAll(value, "\\", "/"))
	value = strings.TrimPrefix(value, "./")
	return strings.TrimPrefix(value, "/")
}

func splitPath(value string) (string, string) {
	idx := strings.LastIndex(value, "/")
	if idx < 0 {
		return "", value
	}
	return value[:idx+1], value[idx+1:]
}