<template>
  <div class="expense-list">
    <!-- Bulk Selection Header -->
    <div v-if="expenses.length > 0" class="d-flex align-center justify-space-between mb-4">
      <div class="d-flex align-center">
        <v-checkbox
          :model-value="isAllSelected"
          :indeterminate="isSomeSelected"
          @update:model-value="toggleSelectAll"
          hide-details
          density="compact"
          class="mr-2"
        />
        <span class="text-body-2 font-weight-medium">
          {{ selectedExpenses.length > 0 ? `${selectedExpenses.length} selected` : 'Select all' }}
        </span>
      </div>
      
      <div class="text-body-2 text-grey-darken-1">
        {{ expenses.length }} expenses • €{{ totalAmount.toFixed(2) }}
      </div>
    </div>

    <!-- Expense Grid -->
    <v-row class="expense-grid">
      <v-col
        v-for="expense in expenses"
        :key="expense.Id"
        cols="12"
        sm="6"
        lg="4"
        xl="3"
      >
        <v-card
          :class="{ 'selected-card': isSelected(expense.Id) }"
          class="expense-card"
          elevation="2"
          @click="selectExpense(expense.Id)"
        >
          <!-- Selection Checkbox -->
          <div class="card-checkbox">
            <v-checkbox
              :model-value="isSelected(expense.Id)"
              @update:model-value="toggleExpense(expense.Id)"
              @click.stop
              hide-details
              density="compact"
              color="primary"
            />
          </div>

          <!-- Receipt Image Section -->
          <div class="receipt-section">
            <div 
              v-if="expense.Receipt && expense.Receipt.length > 0"
              class="receipt-image-container"
              @click.stop="$emit('expense-clicked', expense)"
            >
              <LazyReceiptImage
                :receipt="expense.Receipt[0]"
                :alt="`Receipt for ${expense['Establishment Name']}`"
                class="receipt-image"
              />
              
              <!-- Multiple receipts indicator -->
              <v-chip
                v-if="expense.Receipt.length > 1"
                size="x-small"
                color="primary"
                class="receipt-count-chip"
              >
                +{{ expense.Receipt.length - 1 }}
              </v-chip>
            </div>
            
            <!-- No receipt placeholder -->
            <div 
              v-else 
              class="no-receipt-placeholder"
              @click.stop="$emit('expense-clicked', expense)"
            >
              <v-icon size="48" color="grey-darken-1">mdi-receipt-text-outline</v-icon>
              <span class="text-caption text-grey-darken-2">No receipt</span>
            </div>
          </div>

          <!-- Expense Details -->
          <v-card-text @click.stop="$emit('expense-clicked', expense)">
            <!-- Merchant Name -->
            <div class="merchant-name">
              {{ expense['Establishment Name'] || 'Unknown Merchant' }}
            </div>
            
            <!-- Price -->
            <div class="price-display">
              {{ expense.DisplayPrice || expense.Price }}
              <div v-if="expense.ConversionRate && expense.ConversionRate !== 1" class="d-flex align-center mt-1">
                <v-chip
                  color="info"
                  size="x-small"
                  variant="tonal"
                  class="mr-2"
                >
                  Converted
                </v-chip>
                <span class="converted-price">
                  ≈ ${{ expense.PriceUSD?.toFixed(2) }} USD
                </span>
              </div>
            </div>
            
            <!-- Category and Payment Method -->
            <div class="d-flex align-center justify-space-between my-2">
              <v-chip
                :color="getCategoryColor(expense.Category)"
                size="small"
                variant="tonal"
              >
                {{ expense.Category || 'Other' }}
              </v-chip>
              
              <div class="d-flex align-center">
                <v-icon 
                  :icon="expense['Payment Method'] === 'Card' ? 'mdi-credit-card' : 'mdi-cash'" 
                  size="small"
                  class="mr-1"
                />
                <span class="text-caption">{{ expense['Payment Method'] || 'Unknown' }}</span>
              </div>
            </div>
            
            <!-- Date and Time -->
            <div class="date-display">
              <v-icon size="small" class="mr-1 text-grey-darken-2">mdi-calendar-clock</v-icon>
              {{ formatDateTime(expense.Time) }}
            </div>
            
            <!-- Payer -->
            <div v-if="expense.Payer" class="payer-display">
              <v-icon size="small" class="mr-1 text-grey-darken-2">mdi-account</v-icon>
              {{ expense.Payer }}
            </div>
            
            <!-- Contents Preview -->
            <div v-if="expense.Contents" class="contents-preview">
              {{ getContentsPreview(expense) }}
            </div>
          </v-card-text>

          <!-- Quick Actions -->
          <div class="card-actions">
            <v-btn
              @click.stop="$emit('expense-clicked', expense)"
              icon="mdi-eye"
              size="small"
              variant="elevated"
              color="white"
              class="action-button"
            />
            
            <v-btn
              v-if="expense.Receipt && expense.Receipt.length > 0"
              @click.stop="openReceipt(expense.Receipt[0])"
              icon="mdi-image"
              size="small"
              variant="elevated"
              color="white"
              class="action-button"
            />
          </div>
        </v-card>
      </v-col>
    </v-row>

    <!-- Loading More Indicator -->
    <div v-if="isLoadingMore" class="text-center py-6">
      <v-progress-circular indeterminate color="primary" />
    </div>

    <!-- Empty State -->
    <v-card v-if="expenses.length === 0" class="text-center py-12">
      <v-card-text>
        <v-icon size="64" color="grey-lighten-2" class="mb-4">mdi-receipt</v-icon>
        <h3 class="text-h6 mb-2">No expenses found</h3>
        <p class="text-body-2 text-grey-darken-1">
          No expenses match the current filters
        </p>
      </v-card-text>
    </v-card>
  </div>
</template>

<script setup lang="ts">
import { computed } from 'vue';
import type { Expense } from '@/utils/types';

// Component imports
const LazyReceiptImage = defineAsyncComponent(() => import('@/components/LazyReceiptImage.vue'));

// Props
interface Props {
  expenses: Expense[];
  selectedExpenses: number[];
  isLoadingMore?: boolean;
}

const props = withDefaults(defineProps<Props>(), {
  isLoadingMore: false
});

// Emits
const emit = defineEmits<{
  'update:selected': [expenseIds: number[]];
  'expense-clicked': [expense: Expense];
}>();

// Computed
const totalAmount = computed(() => {
  return props.expenses.reduce((sum, expense) => sum + (expense.PriceNumber || 0), 0);
});

const isAllSelected = computed(() => {
  return props.expenses.length > 0 && props.expenses.every(expense => 
    props.selectedExpenses.includes(expense.Id)
  );
});

const isSomeSelected = computed(() => {
  return props.selectedExpenses.length > 0 && !isAllSelected.value;
});

// Methods
const isSelected = (expenseId: number) => {
  return props.selectedExpenses.includes(expenseId);
};

const selectExpense = (expenseId: number) => {
  // Toggle selection on card click
  toggleExpense(expenseId);
};

const toggleExpense = (expenseId: number) => {
  const currentSelected = [...props.selectedExpenses];
  const index = currentSelected.indexOf(expenseId);
  
  if (index > -1) {
    currentSelected.splice(index, 1);
  } else {
    currentSelected.push(expenseId);
  }
  
  emit('update:selected', currentSelected);
};

const toggleSelectAll = () => {
  if (isAllSelected.value) {
    // Deselect all
    const currentSelected = props.selectedExpenses.filter(id => 
      !props.expenses.some(expense => expense.Id === id)
    );
    emit('update:selected', currentSelected);
  } else {
    // Select all
    const currentSelected = [...props.selectedExpenses];
    props.expenses.forEach(expense => {
      if (!currentSelected.includes(expense.Id)) {
        currentSelected.push(expense.Id);
      }
    });
    emit('update:selected', currentSelected);
  }
};

const formatDateTime = (dateString: string) => {
  try {
    const date = new Date(dateString);
    return date.toLocaleDateString('en-US', {
      month: 'short',
      day: 'numeric',
      hour: '2-digit',
      minute: '2-digit'
    });
  } catch {
    return dateString;
  }
};

const getCategoryColor = (category: string) => {
  const categoryColors: Record<string, string> = {
    'Food/Drinks': 'green',
    'Shop': 'blue',
    'Online': 'purple',
    'Transportation': 'orange',
    'Accommodation': 'teal',
    'Entertainment': 'pink',
    'Other': 'grey'
  };
  
  return categoryColors[category] || 'grey';
};

const getContentsPreview = (expense: Expense) => {
  const content = expense.Contents || '';
  return content.length > 80 ? content.substring(0, 80) + '...' : content;
};

const openReceipt = (receipt: any) => {
  if (receipt.signedUrl) {
    window.open(receipt.signedUrl, '_blank');
  }
};
</script>

<style scoped>
.expense-list {
  width: 100%;
}

.expense-grid {
  margin: 0;
}

.expense-card {
  position: relative;
  cursor: pointer;
  transition: all 0.3s ease;
  height: 100%;
}

.expense-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15) !important;
}

.selected-card {
  border: 2px solid rgb(var(--v-theme-primary)) !important;
  background-color: rgba(var(--v-theme-primary), 0.05);
}

.card-checkbox {
  position: absolute;
  top: 8px;
  left: 8px;
  z-index: 2;
  background: rgba(255, 255, 255, 0.9);
  border-radius: 4px;
  padding: 2px;
}

.receipt-section {
  position: relative;
  height: 140px;
  background: #f5f5f5;
  overflow: hidden;
}

.receipt-image-container {
  width: 100%;
  height: 100%;
  position: relative;
}

.receipt-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.receipt-count-chip {
  position: absolute;
  top: 8px;
  right: 8px;
}

.no-receipt-placeholder {
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: #9e9e9e;
}

.merchant-name {
  font-weight: 600;
  font-size: 1rem;
  line-height: 1.2;
  margin-bottom: 8px;
  color: rgb(var(--v-theme-on-surface));
}

.price-display {
  font-size: 1.25rem;
  font-weight: 700;
  color: rgb(var(--v-theme-primary));
  margin-bottom: 8px;
}

.converted-price {
  font-size: 0.875rem;
  font-weight: 400;
  color: rgb(var(--v-theme-on-surface-variant));
  margin-left: 4px;
}

.date-display {
  display: flex;
  align-items: center;
  font-size: 0.875rem;
  color: rgb(var(--v-theme-on-surface-variant));
  margin-bottom: 4px;
}

.payer-display {
  display: flex;
  align-items: center;
  font-size: 0.875rem;
  color: rgb(var(--v-theme-on-surface-variant));
  margin-bottom: 8px;
}

.contents-preview {
  font-size: 0.875rem;
  color: rgb(var(--v-theme-on-surface-variant));
  line-height: 1.3;
  overflow: hidden;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

.card-actions {
  position: absolute;
  top: 8px;
  right: 8px;
  z-index: 2;
  display: flex;
  gap: 4px;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.expense-card:hover .card-actions {
  opacity: 1;
}

.action-button {
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

/* Responsive adjustments */
@media (max-width: 600px) {
  .expense-grid :deep(.v-col) {
    padding: 6px;
  }
  
  .receipt-section {
    height: 120px;
  }
  
  .merchant-name {
    font-size: 0.9rem;
  }
  
  .price-display {
    font-size: 1.1rem;
  }
}
</style>
