import {createHash,randomUUID} from 'node:crypto';
/**
 * Otomatik e-posta bildirimi abonelikleri (SQLite).
 * Kullanıcı kendi filtre kriterlerini kaydeder; zamanlayıcı yeni eşleşen
 * ihaleleri bulup özet e-posta gönderir.
 */

import fs from 'node:fs';
import path from 'node:path';
import { fileURLToPath } from 'node:url';

let DatabaseSync = null;
try {
  ({ DatabaseSync } = await import('node:sqlite'));
} catch {
  console.warn('[notify-store] node:sqlite yok — otomatik bildirim devre dışı');
}

const __dirname = path.dirname(fileURLToPath(import.meta.url));
const DATA_DIR = process.env.IHALEIST_USER_DATA_DIR || path.join(__dirname, 'data');
const DB_PATH = path.join(DATA_DIR, 'notify.sqlite');
function parseArrayJson(raw, label) {
  try {
    const value = JSON.parse(raw || '[]');
    if (!Array.isArray(value)) throw new Error('dizi değil');
    return value;
  } catch {
    throw new Error(`${label} verisi bozuk; bildirim işlemi durduruldu.`);
  }
}

const SCHEMA = `
CREATE TABLE IF NOT EXISTS abonelikler (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  email TEXT NOT NULL,
  ad TEXT,
  sehir TEXT,
  sektor TEXT,
  alim_turu TEXT,
  anahtar TEXT,
  kurumlar TEXT,          -- JSON: favori kurum listesi
  konular TEXT,           -- JSON: konu başlıkları (kullanıcı seçer)
  aktif INTEGER NOT NULL DEFAULT 1,
  sonGonderim TEXT,
  sonGorulenler TEXT,     -- JSON: son gönderimde bildirilen ihale id'leri
  olusturma TEXT,
  criteria_key TEXT NOT NULL,
  UNIQUE(email, criteria_key)
);
CREATE INDEX IF NOT EXISTS idx_abone_email ON abonelikler(email);
CREATE TABLE IF NOT EXISTS notification_outbox(id TEXT PRIMARY KEY,subscription_id INTEGER NOT NULL,payload TEXT NOT NULL,tender_ids TEXT NOT NULL,state TEXT NOT NULL,first_attempt INTEGER,lease TEXT,lease_until INTEGER,error TEXT,provider_id TEXT);
CREATE TABLE IF NOT EXISTS notification_outbox_reviews(id TEXT PRIMARY KEY,actor TEXT NOT NULL,action TEXT NOT NULL,note TEXT NOT NULL,provider_id TEXT,reviewed_at TEXT NOT NULL);
CREATE UNIQUE INDEX IF NOT EXISTS outbox_active ON notification_outbox(subscription_id) WHERE state IN ('pending','sending','uncertain');
`;

export function available() {
  return Boolean(DatabaseSync);
}

function open({ create = true } = {}) {
  if (!DatabaseSync) return null;
  if (!fs.existsSync(DB_PATH)) {
    if (!create) return null;
    fs.mkdirSync(DATA_DIR, { recursive: true, mode:0o700 });
  }
  const db = new DatabaseSync(DB_PATH);
  try {
    fs.chmodSync(DB_PATH,0o600);
    db.exec('PRAGMA busy_timeout=5000');
    db.exec('BEGIN IMMEDIATE');
    try {
      db.exec(SCHEMA);
      const columns=db.prepare('PRAGMA table_info(abonelikler)').all().map(column=>column.name);
      if(!columns.includes('konular'))db.exec('ALTER TABLE abonelikler ADD COLUMN konular TEXT');
      if(!columns.includes('criteria_key')) {
        const rows=db.prepare('SELECT * FROM abonelikler ORDER BY id').all();
        const sequence=db.prepare("SELECT seq FROM sqlite_sequence WHERE name='abonelikler'").get()?.seq || 0;
        db.exec('ALTER TABLE abonelikler RENAME TO abonelikler_legacy');
        db.exec(SCHEMA);
        const names=['id','email','ad','sehir','sektor','alim_turu','anahtar','kurumlar','konular','aktif','sonGonderim','sonGorulenler','olusturma','criteria_key'];
        const insert=db.prepare(`INSERT INTO abonelikler (${names.join(',')}) VALUES (${names.map(()=>'?').join(',')})`);
        const used=new Set();
        for(const row of rows) {
          const key=subscriptionKey({sehir:row.sehir,sektor:row.sektor,alimTuru:row.alim_turu,anahtar:row.anahtar,
            konular:JSON.parse(row.konular || '[]'),kurumlar:JSON.parse(row.kurumlar || '[]')});
          const identity=JSON.stringify([row.email,key]);
          // Preserve legacy duplicates and their delivery history; do not discard records.
          row.criteria_key=used.has(identity)?key+':legacy:'+row.id:key;used.add(identity);
          insert.run(...names.map(name=>row[name] ?? null));
        }
        db.exec('DROP TABLE abonelikler_legacy');
        db.exec('CREATE INDEX IF NOT EXISTS idx_abone_email ON abonelikler(email)');
        const current=db.prepare("SELECT seq FROM sqlite_sequence WHERE name='abonelikler'").get();
        if(current)db.prepare("UPDATE sqlite_sequence SET seq=? WHERE name='abonelikler'").run(Math.max(sequence,current.seq));
        else db.prepare('INSERT INTO sqlite_sequence(name,seq) VALUES (?,?)').run('abonelikler',sequence);
      }
      db.exec('COMMIT');
    }catch(error){db.exec('ROLLBACK');throw error;}
    return db;
  }catch(error){db.close();throw error;}
}

export function subscriptionKey(criteria) {
 const normal=value=>String(value || '').trim().toLocaleLowerCase('tr-TR');
 const set=values=>{if(!Array.isArray(values))throw new Error('Abonelik konu/kurum listesi geçersiz.');return [...new Set(values.map(normal))].sort();};
 return createHash('sha256').update(JSON.stringify([
  normal(criteria.sehir),normal(criteria.sektor),normal(criteria.alimTuru),normal(criteria.anahtar),set(criteria.konular || []),set(criteria.kurumlar || [])
 ])).digest('hex');
}

const bosaNull = (v) => (v == null || v === '' ? '' : String(v).trim());

export function subscribe(email, kriter = {}, ad = null) {
  if(!kriter||typeof kriter!=='object'||Array.isArray(kriter))throw new Error('Geçersiz bildirim kriterleri.');
  for(const key of ['konular','kurumlar'])if(kriter[key]!==undefined&&(!Array.isArray(kriter[key])||kriter[key].length>100||kriter[key].some(value=>typeof value!=='string'||!value.trim()||value.length>300)))throw new Error('Geçersiz konu veya kurum listesi.');
  for(const key of ['sehir','sektor','alimTuru','anahtar'])if(kriter[key]!==undefined&&(typeof kriter[key]!=='string'||kriter[key].length>300))throw new Error('Geçersiz filtre değeri.');
  const db = open();
  if (!db) throw new Error('Bildirim deposu kullanılamıyor');
  try {
    db.prepare(`
      INSERT INTO abonelikler (email, ad, sehir, sektor, alim_turu, anahtar, kurumlar, konular, aktif, olusturma, criteria_key)
      VALUES (?,?,?,?,?,?,?,?,1,?,?)
      ON CONFLICT(email, criteria_key) DO UPDATE SET
        aktif=1, kurumlar=excluded.kurumlar, konular=excluded.konular, ad=excluded.ad
    `).run(
      email,
      ad,
      bosaNull(kriter.sehir),
      bosaNull(kriter.sektor),
      bosaNull(kriter.alimTuru),
      bosaNull(kriter.anahtar),
      JSON.stringify((kriter.kurumlar || []).map(value=>value.trim())),
      JSON.stringify((kriter.konular || []).map(value=>value.trim())),
      new Date().toISOString(),
      subscriptionKey(kriter)
    );
    return list(email);
  } finally {
    db.close();
  }
}

export function list(email) {
  const db = open({ create: false });
  if (!db) return [];
  try {
    const rows = email
      ? db.prepare('SELECT * FROM abonelikler WHERE email=? ORDER BY id DESC').all(email)
      : db.prepare('SELECT * FROM abonelikler WHERE aktif=1 ORDER BY id').all();
    return rows.map((r) => ({
      id: r.id,
      email: r.email,
      ad: r.ad,
      sehir: r.sehir || null,
      sektor: r.sektor || null,
      alimTuru: r.alim_turu || null,
      anahtar: r.anahtar || null,
      kurumlar: (() => { try { return JSON.parse(r.kurumlar || '[]'); } catch { return []; } })(),
      konular: (() => { try { return JSON.parse(r.konular || '[]'); } catch { return []; } })(),
      aktif: Boolean(r.aktif),
      sonGonderim: r.sonGonderim,
      initialized: r.sonGorulenler !== null,
      deliveryPending:!!db.prepare("SELECT id FROM notification_outbox WHERE subscription_id=? AND state IN ('pending','sending','uncertain')").get(r.id),
      deliveryStatus:db.prepare("SELECT state,error FROM notification_outbox WHERE subscription_id=? AND state IN ('pending','sending','uncertain')").get(r.id) || null,
      sonGorulenler: (() => { try { return JSON.parse(r.sonGorulenler || '[]'); } catch { return []; } })(),
    }));
  } finally {
    db.close();
  }
}

export function remove(id, email) {
  const db = open({ create: false });
  if (!db) return false;
  try {
    db.exec('BEGIN IMMEDIATE');
    try {
      const r=db.prepare('DELETE FROM abonelikler WHERE id=? AND email=?').run(id,email);
      if(r.changes)db.prepare("UPDATE notification_outbox SET state='cancelled' WHERE subscription_id=? AND state IN ('pending','sending','uncertain')").run(id);
      db.exec('COMMIT');return r.changes>0;
    }catch(error){db.exec('ROLLBACK');throw error;}
  } finally {
    db.close();
  }
}

function recordSeen(id,ihaleIdleri,sent) {
  const db=open({create:false});
  if(!db)throw new Error('Bildirim deposu kullanılamıyor');
  try {
    db.exec('BEGIN IMMEDIATE');
    const row=db.prepare('SELECT sonGorulenler FROM abonelikler WHERE id=?').get(id);
    if(!row)throw new Error('Abonelik artık yok.');
    const seen=[...new Set([...parseArrayJson(row.sonGorulenler, 'Görülen ihale'),...ihaleIdleri])];
    db.prepare('UPDATE abonelikler SET sonGorulenler=?,sonGonderim=CASE WHEN ? THEN ? ELSE sonGonderim END WHERE id=?')
      .run(JSON.stringify(seen),sent?1:0,new Date().toISOString(),id);
    db.exec('COMMIT');
  }catch(error){try{db.exec('ROLLBACK');}catch{}throw error;}
  finally{db.close();}
}
export const markSent=(id,ids)=>recordSeen(id,ids,true);
export const markBaseline=(id,ids)=>recordSeen(id,ids,false);

export function reserveDelivery(subscriptionId,payload,tenderIds,{clock=Date.now(),force=false}={}) {
 const db=open();
 try {
  db.exec('BEGIN IMMEDIATE');
  const subscription=db.prepare('SELECT sonGorulenler FROM abonelikler WHERE id=? AND aktif=1').get(subscriptionId);
  if(!subscription){db.exec('COMMIT');return null;}
  let row=db.prepare("SELECT * FROM notification_outbox WHERE subscription_id=? AND state IN ('pending','sending','uncertain')").get(subscriptionId);
  if(!row){
   const seen=new Set(parseArrayJson(subscription.sonGorulenler, 'Görülen ihale'));
   if(!payload||!tenderIds.length||(!force&&tenderIds.some(id=>seen.has(id)))){db.exec('COMMIT');return null;}
   const id=randomUUID();
   db.prepare("INSERT INTO notification_outbox(id,subscription_id,payload,tender_ids,state) VALUES (?,?,?,?,'pending')").run(id,subscriptionId,JSON.stringify(payload),JSON.stringify(tenderIds));
   row=db.prepare('SELECT * FROM notification_outbox WHERE id=?').get(id);
  }
  if(row.state==='uncertain'){db.exec('COMMIT');return {blocked:true};}
  if(row.first_attempt!==null&&clock-row.first_attempt>=23*3600000){
   db.prepare("UPDATE notification_outbox SET state='uncertain',error=? WHERE id=?").run('Gönderim sonucu belirsiz; sağlayıcı kaydı kontrol edilmeden tekrar gönderilmez.',row.id);
   db.exec('COMMIT');return {blocked:true};
  }
  if(row.state==='sending'&&row.lease_until>clock){db.exec('COMMIT');return null;}
  const lease=randomUUID();
  db.prepare("UPDATE notification_outbox SET state='sending',first_attempt=COALESCE(first_attempt,?),lease=?,lease_until=? WHERE id=?").run(clock,lease,clock+120000,row.id);
  db.exec('COMMIT');return {id:row.id,lease,payload:JSON.parse(row.payload),tenderIds:JSON.parse(row.tender_ids)};
  }catch(error){try{db.exec('ROLLBACK');}catch{}throw error;}finally{db.close();}
}
export function acceptDelivery(delivery,providerId) {
 if(typeof providerId!=='string'||!providerId)throw new Error('Sağlayıcı gönderim kimliği gerekli.');
 const db=open();
 try {
  db.exec('BEGIN IMMEDIATE');
  const row=db.prepare("SELECT * FROM notification_outbox WHERE id=? AND lease=? AND state='sending'").get(delivery.id,delivery.lease);
  if(!row)throw new Error('Gönderim kaydı artık etkin değil.');
  const subscription=db.prepare('SELECT sonGorulenler FROM abonelikler WHERE id=?').get(row.subscription_id);
  if(!subscription)throw new Error('Abonelik artık yok.');
  const seen=[...new Set([...parseArrayJson(subscription.sonGorulenler, 'Görülen ihale'),...parseArrayJson(row.tender_ids, 'İhale')])];
  db.prepare('UPDATE abonelikler SET sonGorulenler=?,sonGonderim=? WHERE id=?').run(JSON.stringify(seen),new Date().toISOString(),row.subscription_id);
  db.prepare("UPDATE notification_outbox SET state='sent',provider_id=?,error=NULL WHERE id=?").run(providerId,row.id);
  db.exec('COMMIT');
 }catch(error){try{db.exec('ROLLBACK');}catch{}throw error;}finally{db.close();}
}
export function failDelivery(delivery,error) {
 const db=open();
 try{return db.prepare("UPDATE notification_outbox SET state='pending',error=? WHERE id=? AND lease=? AND state='sending'").run(String(error?.message || error),delivery.id,delivery.lease).changes>0;}
 finally{db.close();}
}

/** Stop replay without altering the pinned request or acknowledging delivery. */
export function holdDelivery(delivery,reason) {
 const db=open();
 try{return db.prepare("UPDATE notification_outbox SET state='uncertain',error=? WHERE id=? AND lease=? AND state='sending'")
  .run(String(reason),delivery.id,delivery.lease).changes>0;}
 finally{db.close();}
}

export function deliveryQueue() {
 const db=open();
 try{return db.prepare("SELECT o.*,r.actor,r.action,r.note,r.reviewed_at FROM notification_outbox o LEFT JOIN notification_outbox_reviews r ON r.id=o.id WHERE o.state IN ('pending','sending','uncertain','sent_manual','skipped') ORDER BY o.first_attempt DESC LIMIT 50").all().map(row=>{
  const payload=JSON.parse(row.payload);
  return {id:row.id,subscriptionId:row.subscription_id,to:payload.to,subject:payload.subject,state:row.state,error:row.error,
   firstAttempt:row.first_attempt,providerId:row.provider_id,review:row.action?{actor:row.actor,action:row.action,note:row.note,at:row.reviewed_at}:null};
 });}finally{db.close();}
}
export function resolveDelivery(id,actor,input) {
 if(typeof id!=='string'||!id||!actor||!['confirmed_sent','skip'].includes(input?.action)||typeof input.note!=='string'||input.note.trim().length<20||input.note.length>2000)throw new Error('Karar ve en az 20 karakterlik kontrol açıklaması gerekli.');
 if(input.action==='confirmed_sent'&&(input.confirmed!==true||typeof input.providerId!=='string'||!input.providerId.trim()||input.providerId.length>200))throw new Error('Sağlayıcı gönderim kimliği ve kontrol onayı gerekli.');
 const db=open();
 try {
  db.exec('BEGIN IMMEDIATE');
  const row=db.prepare("SELECT * FROM notification_outbox WHERE id=? AND state='uncertain'").get(id);
  if(!row)throw Object.assign(new Error('Kayıt artık inceleme beklemiyor. Listeyi yenileyin.'),{status:409});
  const subscription=db.prepare('SELECT sonGorulenler FROM abonelikler WHERE id=?').get(row.subscription_id);
  if(!subscription)throw new Error('Abonelik artık yok.');
  const seen=[...new Set([...parseArrayJson(subscription.sonGorulenler, 'Görülen ihale'),...parseArrayJson(row.tender_ids, 'İhale')])];
  const now=new Date().toISOString(),sent=input.action==='confirmed_sent';
  db.prepare('UPDATE abonelikler SET sonGorulenler=?,sonGonderim=CASE WHEN ? THEN ? ELSE sonGonderim END WHERE id=?').run(JSON.stringify(seen),sent?1:0,now,row.subscription_id);
  db.prepare('INSERT INTO notification_outbox_reviews VALUES (?,?,?,?,?,?)').run(id,actor,input.action,input.note.trim(),sent?input.providerId.trim():null,now);
  db.prepare('UPDATE notification_outbox SET state=?,provider_id=?,error=NULL WHERE id=?').run(sent?'sent_manual':'skipped',sent?input.providerId.trim():null,id);
  db.exec('COMMIT');return {id,state:sent?'sent_manual':'skipped'};
 }catch(error){try{db.exec('ROLLBACK');}catch{}throw error;}finally{db.close();}
}