package fqapi

import (
	"fanqie/internal/common"
	"fmt"
	"strings"
)

var shelfLogger = common.NewLogger("shelf", "INFO", "")

// HandleBookshelf 获取登录用户书架。个人动态数据不缓存。
// group 非空时只返回该分组的书；书架接口对无效/过期 sessionid 也返回空书架，无法区分——
// 空结果时提示重新登录
func HandleBookshelf(sessionID, group string) (string, error) {
	if sessionID == "" {
		return BuildErrorResponse("需要参数 sessionid（在 fanqienovel.com 登录后从浏览器 Cookie 中获取）"), nil
	}

	resp, err := signedBookAPIGet("/reading/bookapi/bookshelf/info/v/", nil, sessionID)
	if err != nil {
		shelfLogger.Error(fmt.Sprintf("获取书架失败: %v", err))
		return BuildErrorResponse("获取书架失败"), err
	}

	items, err := bookAPIList(resp, "book_shelf_info")
	if err != nil {
		return BuildErrorResponse("获取书架失败: " + err.Error()), nil
	}

	// 过滤分组并收集 book_id
	type shelfRow struct {
		id        string
		groupName string
	}
	rows := make([]shelfRow, 0, len(items))
	for _, it := range items {
		m, ok := it.(map[string]interface{})
		if !ok {
			continue
		}
		id := bookIDOf(m)
		if id == "" {
			continue
		}
		gn, _ := m["group_name"].(string)
		if group != "" && gn != group {
			continue
		}
		rows = append(rows, shelfRow{id: id, groupName: gn})
	}

	if len(rows) == 0 {
		return BuildErrorResponse("书架为空：sessionid 可能无效或已过期，请重新获取"), nil
	}

	ids := make([]string, len(rows))
	for i, row := range rows {
		ids[i] = row.id
	}
	details := detailMapByIDs(ids)
	result := make([]map[string]interface{}, 0, len(rows))
	for _, row := range rows {
		d := details[row.id]
		if d == nil {
			d = map[string]interface{}{"book_id": row.id}
		}
		d["group_name"] = row.groupName
		result = append(result, d)
	}

	return marshalNoEscape(UnwrapJSONStrings(buildCacheData(result))), nil
}

// HandleReadHistory 获取登录用户阅读历史。个人动态数据不缓存。
// offset 从 0 起，每页 20 条；每项合并书籍详情并保留原始记录（进度等）于 history 字段
func HandleReadHistory(sessionID string, offset int) (string, error) {
	if sessionID == "" {
		return BuildErrorResponse("需要参数 sessionid（在 fanqienovel.com 登录后从浏览器 Cookie 中获取）"), nil
	}
	if offset < 0 {
		offset = 0
	}

	resp, err := signedBookAPIGet("/reading/bookapi/read_history/list/v/",
		[]string{fmt.Sprintf("offset=%d", offset), "book_type=0"}, sessionID)
	if err != nil {
		shelfLogger.Error(fmt.Sprintf("获取阅读历史失败: %v", err))
		return BuildErrorResponse("获取阅读历史失败"), err
	}

	items, err := bookAPIList(resp, "data_list")
	if err != nil {
		return BuildErrorResponse("获取阅读历史失败: " + err.Error()), nil
	}

	type historyRow struct {
		id  string
		raw map[string]interface{}
	}
	rows := make([]historyRow, 0, len(items))
	for _, it := range items {
		m, ok := it.(map[string]interface{})
		if !ok {
			continue
		}
		id := bookIDOf(m)
		if id == "" {
			continue
		}
		rows = append(rows, historyRow{id: id, raw: m})
	}

	if len(rows) == 0 {
		return marshalNoEscape(buildCacheData([]interface{}{})), nil
	}

	ids := make([]string, len(rows))
	for i, row := range rows {
		ids[i] = row.id
	}
	details := detailMapByIDs(ids)
	result := make([]map[string]interface{}, 0, len(rows))
	for _, row := range rows {
		d := details[row.id]
		if d == nil {
			d = map[string]interface{}{"book_id": row.id}
		}
		// 原始记录（含阅读进度/时间）挂 history 字段保留
		d["history"] = row.raw
		result = append(result, d)
	}

	return marshalNoEscape(UnwrapJSONStrings(buildCacheData(result))), nil
}

// signedBookAPIGet 个人书架/历史接口：常规签名请求 + 登录态 Cookie
func signedBookAPIGet(path string, extraParams []string, sessionID string) (*common.ClientResponse, error) {
	reqURL := BuildURL("https://reading.snssdk.com"+path, extraParams...)
	return GorgonRequest(reqURL, map[string]interface{}{
		"method": "GET",
		"headers": map[string]string{
			"User-Agent": "com.dragon.read",
			"Cookie":     "sessionid=" + sessionID,
		},
	})
}

// bookAPIList 校验上游响应并取出 data 下的指定列表字段
func bookAPIList(resp *common.ClientResponse, field string) ([]interface{}, error) {
	respJSON, err := resp.JSON()
	if err != nil {
		return nil, fmt.Errorf("响应解析失败: %w", err)
	}
	if code, ok := respJSON["code"].(float64); !ok || code != 0 {
		msg, _ := respJSON["message"].(string)
		return nil, fmt.Errorf("code=%.0f msg=%s", respJSON["code"], msg)
	}
	data, _ := respJSON["data"].(map[string]interface{})
	items, _ := data[field].([]interface{})
	return items, nil
}

// bookIDOf 兼容提取 book_id / book_id_str（数字或字符串）
func bookIDOf(m map[string]interface{}) string {
	for _, k := range []string{"book_id_str", "book_id", "bookId"} {
		switch v := m[k].(type) {
		case string:
			if v != "" {
				return v
			}
		case float64:
			return fmt.Sprintf("%.0f", v)
		}
	}
	return ""
}

// detailMapByIDs 按 book_id 建立详情映射（复用批量详情接口，分批请求）
func detailMapByIDs(ids []string) map[string]map[string]interface{} {
	m := make(map[string]map[string]interface{}, len(ids))
	for _, chunk := range chunkArray(ids, 100) {
		list, err := multiDetail(strings.Join(chunk, ","))
		if err != nil {
			shelfLogger.Warning(fmt.Sprintf("批量获取详情失败（该批保留 book_id）: %v", err))
			continue
		}
		for _, d := range list {
			if id, ok := d["book_id"].(string); ok {
				m[id] = d
			}
		}
	}
	return m
}