/**
 * Score — manages TG score submission and retrieval.
 *
 * Usage:
 *   import { Score } from "@systems/score";
 *
 *   Score.get({ character, slot, date })
 *   Score.getWeeklySummary({ userKey })
 *   Score.submit({ character, borrowedFrom, pts, k, d, slot })
 */

 import { Character, Nation, UserKey, HistoryKey, SlotHour } from "@types";
 import { WRank } from "@systems/wrank";
 import { Store } from "@systems/store";
 import { Paths } from "@helpers/paths";
 
 export interface TGScore {
   userKey:            UserKey;
   playedBy?:          UserKey;       // if borrowed
   characterName:      string;
   class:              string;
   nation:             Nation;
   pts:                number;
   k?:                 number;
   d?:                 number;
   atk?:              number;
   def?:              number;
   heal?:             number;
   submittedAt:        string;
   slot:               SlotHour;
   date:               string;
   submittedByOfficer: boolean;
   wRankAtSubmission?: {
     rank:  number;
     delta: number;
   };
 }
 
 export interface WeeklySummary {
   userKey:    UserKey;
   character:  Character;
   scores:     TGScore[];
   totalPts:   number;
   totalK:     number;
   totalD:     number;
   tgCount:    number;
   currentRank?: number;
   previousRank?: number;
 }
 
 function getHistoryPath(historyKey: HistoryKey): string {
   return Paths.data("tg-history", `${historyKey}.json`);
 }
 
 function loadHistory(historyKey: HistoryKey): { scores: TGScore[] } {
  return Store.readOrDefault(getHistoryPath(historyKey), { scores: [] });
}
function saveHistory(historyKey: HistoryKey, data: { scores: TGScore[] }): void {
  Store.write(getHistoryPath(historyKey), data);
}
 
 export const Score = {
   /**
    * Get a score for a character in a specific TG.
    */
   get({ character, slot, date }: {
     character: Character;
     slot:      SlotHour;
     date?:     string;
   }): TGScore | null {
     const d          = date ?? new Date().toISOString().slice(0, 10);
     const historyKey = `${d}-${slot}` as HistoryKey;
     const history    = loadHistory(historyKey);
     return history.scores.find(
       (s) => s.userKey === character.ownerKey && s.characterName === character.name
     ) ?? null;
   },
 
   /**
    * Get weekly summary for a character.
    */
   getWeeklySummary({ character }: { character: Character }): WeeklySummary {
     const week    = WRank.currentWeek();
     const entry   = WRank.entry(character.name, character.nation);
     const allKeys = Object.keys(week.scoreIndex[character.name] ?? {}) as HistoryKey[];
 
     const scores: TGScore[] = [];
     for (const historyKey of (week.scoreIndex[character.name] ?? [])) {
       const history = loadHistory(historyKey as HistoryKey);
       const score   = history.scores.find(
         (s) => s.userKey === character.ownerKey && s.characterName === character.name
       );
       if (score) scores.push(score);
     }
 
     const totalPts = scores.reduce((sum, s) => sum + s.pts, 0);
     const totalK   = scores.reduce((sum, s) => sum + (s.k ?? 0), 0);
     const totalD   = scores.reduce((sum, s) => sum + (s.d ?? 0), 0);
 
     return {
       userKey:      character.ownerKey,
       character,
       scores,
       totalPts,
       totalK,
       totalD,
       tgCount:      scores.length,
       currentRank:  entry?.currentRank,
       previousRank: entry?.previousRank,
     };
   },
 
   /**
    * Submit a score for a character.
    * Handles W.Rank snapshot at submission time.
    */
   submit({ character, borrowedFrom, pts, k, d, atk, def, heal, slot, submittedByOfficer }: {
     character:          Character;
     borrowedFrom?:      UserKey;
     pts:                number;
     k?:                 number;
     d?:                 number;
     atk?:              number;
     def?:              number;
     heal?:             number;
     slot:               SlotHour;
     submittedByOfficer?: boolean;
   }): void {
     const date       = new Date().toISOString().slice(0, 10);
     const historyKey = `${date}-${slot}` as HistoryKey;
     const history    = loadHistory(historyKey);
 
     // Snapshot W.Rank before recording score
     const existingEntry = WRank.entry(character.name, character.nation);
     const wRankAtSubmission = existingEntry ? {
       rank:  existingEntry.currentRank,
       delta: existingEntry.currentRank - (existingEntry.previousRank ?? existingEntry.currentRank),
     } : undefined;
 
     const score: TGScore = {
       userKey:            character.ownerKey,
       playedBy:           borrowedFrom,
       characterName:      character.name,
       class:              character.class.key,
       nation:             character.nation,
       pts,
       k,
       d,
       atk,
       def,
       heal,
       submittedAt:        new Date().toISOString(),
       slot,
       date,
       submittedByOfficer: submittedByOfficer ?? false,
       wRankAtSubmission,
     };
 
     // Upsert — replace existing score for same character/slot
     history.scores = history.scores.filter(
       (s) => !(s.userKey === character.ownerKey &&
                s.characterName === character.name &&
                s.slot === slot &&
                s.date === date)
     );
     history.scores.push(score);
     saveHistory(historyKey, history);
 
     // Record in W.Rank
     WRank.recordScore(
       character.ownerKey,
       character.name,
       character.class.key,
       character.nation,
       pts,
       historyKey
     );
   },
 };