import { ExcelRow } from '../types';

const SUPABASE_URL = 'https://hwithddwaapyhnfwcesj.supabase.co';
const SUPABASE_KEY = 'sb_publishable_fGXkh0bSrAOqSk2jWKAzSg_NJD9YPCv';

async function fetchWithRetry(
  url: string,
  options: RequestInit,
  retries = 2,
  delayMs = 1000
): Promise<Response> {
  let lastError: Error | null = null;
  for (let attempt = 0; attempt <= retries; attempt++) {
    try {
      const res = await fetch(url, options);
      if (res.ok || res.status < 500 || attempt === retries) return res;
    } catch (err) {
      lastError = err as Error;
      if (attempt === retries) throw lastError;
    }
    await new Promise(r => setTimeout(r, delayMs));
  }
  throw lastError ?? new Error('fetch failed');
}

export async function saveRowToSupabase(articleNo: string, rowData: ExcelRow): Promise<boolean> {
  try {
    // Single upsert: POST with Prefer=resolution=merge-duplicates
    // This handles both INSERT (new article) and UPDATE (existing) atomically.
    // The old PATCH approach silently failed for new articles because Supabase
    // returns 200 OK with an empty body when no rows match — indistinguishable
    // from a successful update.
    const response = await fetchWithRetry(`${SUPABASE_URL}/rest/v1/products_sync`, {
      method: 'POST',
      headers: {
        'apikey': SUPABASE_KEY,
        'Authorization': `Bearer ${SUPABASE_KEY}`,
        'Content-Type': 'application/json',
        'Prefer': 'resolution=merge-duplicates'
      },
      body: JSON.stringify({
        id: articleNo,
        data: rowData,
        status_check: 'pending',
        updated_at: new Date().toISOString()
      })
    });

    if (!response.ok) {
      const errorData = await response.json().catch(() => ({}));
      console.error('Supabase upsert failed:', response.status, errorData);
      return false;
    }
    return true;
  } catch (error) {
    console.error('Error saving to Supabase:', error);
    return false;
  }
}

export async function getAllSyncedRows(): Promise<Record<string, { data: ExcelRow, status: string }>> {
  try {
    // Explicit limit to avoid Supabase's default 1000-row cap
    const response = await fetch(
      `${SUPABASE_URL}/rest/v1/products_sync?select=id,data,status_check&limit=10000`,
      {
        headers: {
          'apikey': SUPABASE_KEY,
          'Authorization': `Bearer ${SUPABASE_KEY}`,
          'Range': '0-9999'
        }
      }
    );

    if (!response.ok) return {};

    const data = await response.json();
    const result: Record<string, { data: ExcelRow, status: string }> = {};
    data.forEach((item: any) => {
      result[item.id] = {
        data: item.data,
        status: item.status_check || 'original'
      };
    });
    return result;
  } catch (error) {
    console.error('Error fetching from Supabase:', error);
    return {};
  }
}

export async function resetAllPendingRows(): Promise<boolean> {
  try {
    const response = await fetch(`${SUPABASE_URL}/rest/v1/products_sync?status_check=eq.pending`, {
      method: 'PATCH',
      headers: {
        'apikey': SUPABASE_KEY,
        'Authorization': `Bearer ${SUPABASE_KEY}`,
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({
        status_check: 'original',
        updated_at: new Date().toISOString()
      })
    });
    return response.ok;
  } catch (error) {
    console.error('Error resetting statuses in Supabase:', error);
    return false;
  }
}

export interface HistoryEntry {
  id: string;
  product_id: string;
  article_name: string;
  old_data: ExcelRow;
  new_data: ExcelRow;
  changed_at: string;
  changed_by: string;
}

export async function saveHistoryEntry(
  articleNo: string,
  articleName: string,
  oldData: ExcelRow,
  newData: ExcelRow,
  userEmail: string
): Promise<boolean> {
  try {
    const response = await fetch(`${SUPABASE_URL}/rest/v1/products_history`, {
      method: 'POST',
      headers: {
        'apikey': SUPABASE_KEY,
        'Authorization': `Bearer ${SUPABASE_KEY}`,
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({
        product_id: articleNo,
        article_name: articleName,
        old_data: oldData,
        new_data: newData,
        changed_at: new Date().toISOString(),
        changed_by: userEmail
      })
    });

    return response.ok;
  } catch (error) {
    console.error('Error saving history to Supabase:', error);
    return false;
  }
}

export async function getHistory(): Promise<HistoryEntry[]> {
  try {
    const response = await fetch(
      `${SUPABASE_URL}/rest/v1/products_history?select=*&order=changed_at.desc&limit=100`,
      {
        headers: {
          'apikey': SUPABASE_KEY,
          'Authorization': `Bearer ${SUPABASE_KEY}`
        }
      }
    );

    if (!response.ok) return [];
    return await response.json();
  } catch (error) {
    console.error('Error fetching history from Supabase:', error);
    return [];
  }
}