'use client';

import { useState, useEffect } from 'react';
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogHeader,
  DialogTitle,
} from '@/components/ui/dialog';
import { Button } from '@/components/ui/button';
import { Badge } from '@/components/ui/badge';
import { Skeleton } from '@/components/ui/skeleton';
import {
  Table,
  TableBody,
  TableCell,
  TableHead,
  TableHeader,
  TableRow,
} from '@/components/ui/table';
import { DollarSign, FileText, AlertCircle, Receipt } from 'lucide-react';
import { format } from 'date-fns';

interface PurchaseHistoryModalProps {
  configItemId: number;
  serialNumber?: string;
  createDate?: string;
  open: boolean;
  onOpenChange: (open: boolean) => void;
}

interface PurchaseHistoryData {
  billingItems: any[];
  invoices?: any[];
}

export function PurchaseHistoryModal({
  configItemId,
  serialNumber,
  createDate,
  open,
  onOpenChange,
}: PurchaseHistoryModalProps) {
  const [data, setData] = useState<PurchaseHistoryData | null>(null);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState<string | null>(null);
  const [searchAttempt, setSearchAttempt] = useState(0); // 0 = initial, 1 = before, 2 = after
  const [selectedInvoice, setSelectedInvoice] = useState<any>(null);
  const [selectedTicket, setSelectedTicket] = useState<any>(null);
  const [loadingTicket, setLoadingTicket] = useState(false);
  const [timeEntries, setTimeEntries] = useState<any[]>([]);
  const [loadingTimeEntries, setLoadingTimeEntries] = useState(false);
  const [showTimeEntries, setShowTimeEntries] = useState(false);
  const [invoiceLineItems, setInvoiceLineItems] = useState<any[]>([]);
  const [loadingInvoiceItems, setLoadingInvoiceItems] = useState(false);
  const [showInvoiceItems, setShowInvoiceItems] = useState(false);

  useEffect(() => {
    if (open && configItemId) {
      setSearchAttempt(0); // Reset search attempt
      fetchPurchaseHistory(0);
    }
  }, [open, configItemId]);

  const fetchPurchaseHistory = async (attempt: number) => {
    setLoading(true);
    setError(null);

    try {
      // Calculate date range based on creation date and attempt
      let startDate: Date;
      let endDate: Date;
      
      if (!createDate) {
        // Fallback if no creation date: search last 120 days
        endDate = new Date();
        startDate = new Date();
        startDate.setDate(startDate.getDate() - 120);
      } else {
        const created = new Date(createDate);
        
        if (attempt === 0) {
          // Initial: 60 days before to 60 days after creation
          startDate = new Date(created);
          startDate.setDate(startDate.getDate() - 60);
          endDate = new Date(created);
          endDate.setDate(endDate.getDate() + 60);
          console.log('Initial search: 60 days before/after creation date');
        } else if (attempt === 1) {
          // Second attempt: 120 days before the initial window
          startDate = new Date(created);
          startDate.setDate(startDate.getDate() - 180); // 60 + 120
          endDate = new Date(created);
          endDate.setDate(endDate.getDate() - 60);
          console.log('Extended search: 120 days BEFORE initial window');
        } else {
          // Third attempt: 120 days after the initial window
          startDate = new Date(created);
          startDate.setDate(startDate.getDate() + 60);
          endDate = new Date(created);
          endDate.setDate(endDate.getDate() + 180); // 60 + 120
          console.log('Extended search: 120 days AFTER initial window');
        }
      }
      
      const url = `/api/config-enrichment?configItemId=${configItemId}&startDate=${startDate.toISOString().split('T')[0]}&endDate=${endDate.toISOString().split('T')[0]}`;
      console.log('Fetching from:', url);
      const response = await fetch(url);
      console.log('Response status:', response.status);
      
      if (!response.ok) {
        const errorText = await response.text();
        console.error('Error response:', errorText);
        throw new Error('Failed to fetch purchase history');
      }

      const result = await response.json();
      console.log('Purchase history result:', result);
      
      // If no results and we haven't tried all attempts yet, try next window
      if (result.billingItems.length === 0 && attempt < 2) {
        console.log('No results found, trying extended search...');
        setSearchAttempt(attempt + 1);
        await fetchPurchaseHistory(attempt + 1);
      } else {
        setData(result);
        setSearchAttempt(attempt);
      }
    } catch (err) {
      console.error('Purchase history error:', err);
      setError(err instanceof Error ? err.message : 'An error occurred');
    } finally {
      setLoading(false);
    }
  };

  const fetchTicketDetails = async (ticketId: number) => {
    console.log('Fetching ticket details for ID:', ticketId);
    setLoadingTicket(true);
    setShowTimeEntries(false);
    setTimeEntries([]);
    try {
      const url = `/api/tickets/${ticketId}`;
      console.log('Fetching from:', url);
      const response = await fetch(url);
      console.log('Response status:', response.status);
      
      if (!response.ok) {
        const errorText = await response.text();
        console.error('Error response:', errorText);
        throw new Error('Failed to fetch ticket details');
      }
      
      const result = await response.json();
      console.log('Ticket result:', result);
      setSelectedTicket(result.ticket);
    } catch (err) {
      console.error('Error fetching ticket:', err);
      setSelectedTicket({ ticketNumber: ticketId, title: 'Error loading ticket details' });
    } finally {
      setLoadingTicket(false);
    }
  };

  const fetchTimeEntries = async (ticketId: number) => {
    setLoadingTimeEntries(true);
    try {
      const response = await fetch(`/api/tickets/${ticketId}/time-entries`);
      if (!response.ok) {
        throw new Error('Failed to fetch time entries');
      }
      const result = await response.json();
      setTimeEntries(result.timeEntries || []);
      setShowTimeEntries(true);
    } catch (err) {
      console.error('Error fetching time entries:', err);
      setTimeEntries([]);
    } finally {
      setLoadingTimeEntries(false);
    }
  };

  const fetchInvoiceLineItems = async (invoiceId: number) => {
    setLoadingInvoiceItems(true);
    try {
      const response = await fetch(`/api/invoices/${invoiceId}/line-items`);
      if (!response.ok) {
        throw new Error('Failed to fetch invoice line items');
      }
      const result = await response.json();
      setInvoiceLineItems(result.lineItems || []);
      setShowInvoiceItems(true);
    } catch (err) {
      console.error('Error fetching invoice line items:', err);
      setInvoiceLineItems([]);
    } finally {
      setLoadingInvoiceItems(false);
    }
  };

  return (
    <Dialog open={open} onOpenChange={onOpenChange}>
      <DialogContent className="!max-w-[95vw] !w-[95vw] max-h-[90vh] overflow-y-auto">
        <DialogHeader>
          <div className="flex items-start justify-between gap-4">
            <div className="flex-1">
              <DialogTitle className="flex items-center gap-2">
                <Receipt className="w-5 h-5" />
                Purchase History
              </DialogTitle>
              <DialogDescription>
                Hardware purchase history for this device
                {serialNumber && ` - Serial: ${serialNumber}`}
                {createDate && (
                  <span className="block text-xs mt-1">
                    Searching around creation date: {format(new Date(createDate), 'MMM d, yyyy')}
                    {searchAttempt > 0 && ` (Extended search ${searchAttempt}/2)`}
                  </span>
                )}
              </DialogDescription>
            </div>
            {/* Summary Cards - Compact */}
            {!loading && !error && data && data.billingItems.length > 0 && (
              <div className="flex gap-3 mr-8">
                <div className="px-3 py-2 bg-gradient-to-br from-green-50 to-green-100 dark:from-green-950 dark:to-green-900 rounded-lg">
                  <p className="text-xs text-muted-foreground">Sale Price</p>
                  <p className="text-sm font-bold">
                    ${data.billingItems.reduce((sum: number, item: any) => sum + (Number(item.totalAmount) || 0), 0).toFixed(2)}
                  </p>
                </div>
                <div className="px-3 py-2 bg-gradient-to-br from-blue-50 to-blue-100 dark:from-blue-950 dark:to-blue-900 rounded-lg">
                  <p className="text-xs text-muted-foreground">Cost</p>
                  <p className="text-sm font-bold">
                    ${data.billingItems.reduce((sum: number, item: any) => sum + (Number(item.ourCost) || 0), 0).toFixed(2)}
                  </p>
                </div>
                <div className="px-3 py-2 bg-gradient-to-br from-purple-50 to-purple-100 dark:from-purple-950 dark:to-purple-900 rounded-lg">
                  <p className="text-xs text-muted-foreground">Profit</p>
                  <p className="text-sm font-bold">
                    ${data.billingItems.reduce((sum: number, item: any) => sum + (Number(item.profit) || 0), 0).toFixed(2)}
                  </p>
                </div>
              </div>
            )}
          </div>
        </DialogHeader>

        {loading && (
          <div className="space-y-4 py-4">
            <Skeleton className="h-24 w-full" />
            <Skeleton className="h-64 w-full" />
          </div>
        )}

        {error && (
          <div className="flex items-center gap-2 text-red-500 p-4 bg-red-50 dark:bg-red-950/20 rounded-lg">
            <AlertCircle className="w-5 h-5" />
            <p>Error: {error}</p>
          </div>
        )}

        {!loading && !error && data && (
          <div className="space-y-6 py-4">
            {/* Billing Items */}
            {data.billingItems.length > 0 ? (
              <div>
                <h3 className="text-lg font-semibold mb-4 flex items-center gap-2">
                  <FileText className="w-5 h-5" />
                  Purchase Details
                </h3>
                <div className="border rounded-lg overflow-hidden overflow-x-auto">
                  <Table>
                    <TableHeader>
                      <TableRow>
                        <TableHead className="w-28">Date</TableHead>
                        <TableHead className="min-w-[300px] max-w-[400px]">Description</TableHead>
                        <TableHead className="w-32">Serial</TableHead>
                        <TableHead className="w-24">Cost</TableHead>
                        <TableHead className="w-24">Sale Price</TableHead>
                        <TableHead className="w-24">Profit</TableHead>
                        <TableHead className="w-24">Invoice</TableHead>
                        <TableHead className="w-24">Ticket</TableHead>
                      </TableRow>
                    </TableHeader>
                    <TableBody>
                      {data.billingItems.map((item: any, index: number) => (
                        <TableRow key={index}>
                          <TableCell className="whitespace-nowrap">
                            {item.itemDate ? format(new Date(item.itemDate), 'MMM d, yyyy') : '-'}
                          </TableCell>
                          <TableCell className="min-w-[300px] max-w-[400px]">
                            <div className="text-sm font-medium whitespace-normal break-words">{item.description}</div>
                            {item.purchaseOrderNumber && (
                              <div className="text-xs text-muted-foreground">PO: {item.purchaseOrderNumber}</div>
                            )}
                          </TableCell>
                          <TableCell>
                            {item.extractedSerialNumber && (
                              <span className="font-mono text-xs bg-green-100 dark:bg-green-900 px-2 py-1 rounded">
                                {item.extractedSerialNumber}
                              </span>
                            )}
                          </TableCell>
                          <TableCell className="whitespace-nowrap">
                            ${(item.ourCost || 0).toFixed(2)}
                          </TableCell>
                          <TableCell className="whitespace-nowrap font-medium">
                            ${(item.totalAmount || 0).toFixed(2)}
                          </TableCell>
                          <TableCell className="whitespace-nowrap">
                            <span className={item.profit > 0 ? 'text-green-600' : 'text-red-600'}>
                              ${(item.profit || 0).toFixed(2)}
                            </span>
                            <Badge variant="secondary" className="ml-2">
                              {item.profitMargin}%
                            </Badge>
                          </TableCell>
                          <TableCell>
                            {item.invoiceID ? (
                              <Button
                                variant="link"
                                size="sm"
                                className="h-auto p-0 font-mono text-blue-600 hover:text-blue-800"
                                onClick={() => {
                                  const invoice = data.invoices?.find((inv: any) => inv.id === item.invoiceID);
                                  setSelectedInvoice(invoice || { id: item.invoiceID });
                                }}
                              >
                                {item.invoiceID}
                              </Button>
                            ) : '-'}
                          </TableCell>
                          <TableCell>
                            {item.ticketID ? (
                              <Button
                                variant="link"
                                size="sm"
                                className="h-auto p-0 font-mono text-blue-600 hover:text-blue-800"
                                onClick={() => fetchTicketDetails(item.ticketID)}
                              >
                                {item.ticketID}
                              </Button>
                            ) : '-'}
                          </TableCell>
                        </TableRow>
                      ))}
                    </TableBody>
                  </Table>
                </div>
              </div>
            ) : (
              <div className="text-center py-12 text-muted-foreground">
                <AlertCircle className="w-12 h-12 mx-auto mb-4 opacity-50" />
                <p className="font-medium">No purchase records found for this serial number</p>
                <p className="text-sm mt-2">
                  Serial number: {serialNumber || 'Not set'}
                </p>
                <p className="text-sm mt-4">This device may have been:</p>
                <ul className="text-sm mt-2 space-y-1">
                  <li>• Purchased more than 90 days ago</li>
                  <li>• Added manually without an invoice</li>
                  <li>• Serial number not found in invoice line items</li>
                </ul>
              </div>
            )}
          </div>
        )}
        
        {/* Invoice Details Section */}
        {selectedInvoice && (
          <div className="mt-6 border-t pt-6">
            <div className="flex items-center justify-between mb-4">
              <h3 className="text-lg font-semibold flex items-center gap-2">
                <FileText className="w-5 h-5" />
                Invoice #{selectedInvoice.id} Details
              </h3>
              <Button
                variant="ghost"
                size="sm"
                onClick={() => setSelectedInvoice(null)}
              >
                Close
              </Button>
            </div>
            <div className="grid grid-cols-2 md:grid-cols-4 gap-4 p-4 bg-gray-50 dark:bg-gray-900 rounded-lg">
              <div>
                <p className="text-sm text-muted-foreground">Invoice Date</p>
                <p className="font-medium">
                  {selectedInvoice.invoiceDateTime ? format(new Date(selectedInvoice.invoiceDateTime), 'MMM d, yyyy') : '-'}
                </p>
              </div>
              <div>
                <p className="text-sm text-muted-foreground">Total</p>
                <p className="font-medium">${(selectedInvoice.invoiceTotal || 0).toFixed(2)}</p>
              </div>
              <div>
                <p className="text-sm text-muted-foreground">Status</p>
                <Badge variant={selectedInvoice.isPaid ? 'default' : 'secondary'}>
                  {selectedInvoice.isPaid ? 'Paid' : 'Unpaid'}
                </Badge>
              </div>
              <div>
                <p className="text-sm text-muted-foreground">Due Date</p>
                <p className="font-medium">
                  {selectedInvoice.dueDateTime ? format(new Date(selectedInvoice.dueDateTime), 'MMM d, yyyy') : '-'}
                </p>
              </div>
            </div>
            
            {/* Invoice Line Items */}
            <div className="mt-4">
              <Button
                variant="outline"
                size="sm"
                onClick={() => {
                  if (!showInvoiceItems && invoiceLineItems.length === 0) {
                    fetchInvoiceLineItems(selectedInvoice.id);
                  } else {
                    setShowInvoiceItems(!showInvoiceItems);
                  }
                }}
                className="w-full"
              >
                {showInvoiceItems ? 'Hide' : 'Show'} Line Items
                {invoiceLineItems.length > 0 && ` (${invoiceLineItems.length})`}
              </Button>
              
              {loadingInvoiceItems && (
                <div className="mt-4">
                  <Skeleton className="h-32 w-full" />
                </div>
              )}
              
              {showInvoiceItems && invoiceLineItems.length > 0 && (
                <div className="mt-4 overflow-x-auto">
                  <Table>
                    <TableHeader>
                      <TableRow>
                        <TableHead className="min-w-[300px] max-w-[500px]">Description</TableHead>
                        <TableHead className="text-right w-20">Qty</TableHead>
                        <TableHead className="text-right w-28">Unit Price</TableHead>
                        <TableHead className="text-right w-28">Total</TableHead>
                      </TableRow>
                    </TableHeader>
                    <TableBody>
                      {invoiceLineItems.map((item: any, index: number) => (
                        <TableRow key={index}>
                          <TableCell className="min-w-[300px] max-w-[500px]">
                            <div className="text-sm font-medium whitespace-normal break-words">{item.description || '-'}</div>
                          </TableCell>
                          <TableCell className="text-right whitespace-nowrap">{item.quantity || 0}</TableCell>
                          <TableCell className="text-right whitespace-nowrap">${(item.unitPrice || 0).toFixed(2)}</TableCell>
                          <TableCell className="text-right font-medium whitespace-nowrap">${(item.totalAmount || 0).toFixed(2)}</TableCell>
                        </TableRow>
                      ))}
                    </TableBody>
                  </Table>
                </div>
              )}
              
              {showInvoiceItems && invoiceLineItems.length === 0 && !loadingInvoiceItems && (
                <p className="text-sm text-muted-foreground mt-4 text-center">No line items found</p>
              )}
            </div>
          </div>
        )}
        
        {/* Ticket Details Section */}
        {selectedTicket && (
          <div className="mt-6 border-t pt-6">
            <div className="flex items-center justify-between mb-4">
              <h3 className="text-lg font-semibold flex items-center gap-2">
                <FileText className="w-5 h-5" />
                Ticket #{selectedTicket.ticketNumber} Details
              </h3>
              <Button
                variant="ghost"
                size="sm"
                onClick={() => setSelectedTicket(null)}
              >
                Close
              </Button>
            </div>
            {loadingTicket ? (
              <Skeleton className="h-24 w-full" />
            ) : (
              <div className="grid grid-cols-1 md:grid-cols-3 gap-4 p-4 bg-gray-50 dark:bg-gray-900 rounded-lg">
                <div>
                  <p className="text-sm text-muted-foreground">Ticket Number</p>
                  <p className="font-medium">{selectedTicket.ticketNumber}</p>
                </div>
                <div className="md:col-span-2">
                  <p className="text-sm text-muted-foreground">Description</p>
                  <p className="font-medium">{selectedTicket.title || '-'}</p>
                </div>
                <div>
                  <p className="text-sm text-muted-foreground">Primary Resource</p>
                  <p className="font-medium">{selectedTicket.assignedResourceName || '-'}</p>
                </div>
                <div>
                  <p className="text-sm text-muted-foreground">Status</p>
                  <Badge>{selectedTicket.status || '-'}</Badge>
                </div>
                <div>
                  <p className="text-sm text-muted-foreground">Created</p>
                  <p className="font-medium">
                    {selectedTicket.createDate ? format(new Date(selectedTicket.createDate), 'MMM d, yyyy') : '-'}
                  </p>
                </div>
              </div>
            )}
            
            {/* Time Entries Timeline */}
            <div className="mt-4">
              <Button
                variant="outline"
                size="sm"
                onClick={() => {
                  if (!showTimeEntries && timeEntries.length === 0) {
                    fetchTimeEntries(selectedTicket.id);
                  } else {
                    setShowTimeEntries(!showTimeEntries);
                  }
                }}
                className="w-full"
              >
                {showTimeEntries ? 'Hide' : 'Show'} Time Entries Timeline
                {timeEntries.length > 0 && ` (${timeEntries.length})`}
              </Button>
              
              {loadingTimeEntries && (
                <div className="mt-4">
                  <Skeleton className="h-32 w-full" />
                </div>
              )}
              
              {showTimeEntries && timeEntries.length > 0 && (
                <div className="mt-4 space-y-3">
                  {timeEntries.map((entry: any, index: number) => (
                    <div key={index} className="flex gap-3 p-3 bg-white dark:bg-gray-800 rounded-lg border">
                      <div className="flex-shrink-0 w-1 bg-blue-500 rounded"></div>
                      <div className="flex-1">
                        <div className="flex items-start justify-between">
                          <div>
                            <p className="font-medium text-sm">{entry.resourceName || 'Unknown Resource'}</p>
                            <p className="text-xs text-muted-foreground">
                              {entry.dateWorked ? format(new Date(entry.dateWorked), 'MMM d, yyyy') : '-'}
                            </p>
                          </div>
                          <Badge variant="secondary">{entry.hoursWorked || 0}h</Badge>
                        </div>
                        {entry.summaryNotes && (
                          <p className="text-sm mt-2 text-muted-foreground">{entry.summaryNotes}</p>
                        )}
                      </div>
                    </div>
                  ))}
                </div>
              )}
              
              {showTimeEntries && timeEntries.length === 0 && !loadingTimeEntries && (
                <p className="text-sm text-muted-foreground mt-4 text-center">No time entries found</p>
              )}
            </div>
          </div>
        )}
      </DialogContent>
    </Dialog>
  );
}