71 lines
2.3 KiB
Python
71 lines
2.3 KiB
Python
from decimal import Decimal
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import math
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from .models import PricingRule, PlatformProfile
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def calculate_haversine_distance(lat1, lon1, lat2, lon2):
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"""
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Calculate the great circle distance in kilometers between two points
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on the earth (specified in decimal degrees)
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"""
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if lat1 is None or lon1 is None or lat2 is None or lon2 is None:
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return Decimal('0.00')
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# Convert decimal degrees to radians
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lat1, lon1, lat2, lon2 = map(math.radians, [float(lat1), float(lon1), float(lat2), float(lon2)])
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# Haversine formula
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dlon = lon2 - lon1
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dlat = lat2 - lat1
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a = math.sin(dlat/2)**2 + math.cos(lat1) * math.cos(lat2) * math.sin(dlon/2)**2
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c = 2 * math.asin(math.sqrt(a))
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r = 6371 # Radius of earth in kilometers. Use 3956 for miles
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return Decimal(c * r)
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def get_pricing_breakdown(distance_km, weight_kg):
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"""
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Returns a dictionary with pricing breakdown:
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{
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'price': Decimal,
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'platform_fee': Decimal,
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'platform_fee_percentage': Decimal,
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'driver_amount': Decimal,
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'error': str (optional)
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}
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"""
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# 1. Find matching rule
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# We look for a rule that covers this distance and weight
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rule = PricingRule.objects.filter(
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min_distance__lte=distance_km,
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max_distance__gte=distance_km,
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min_weight__lte=weight_kg,
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max_weight__gte=weight_kg
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).first()
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if not rule:
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# Fallback or Error
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# Try to find a rule just by distance if weight is slightly off? No, strict for now.
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return {
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'price': Decimal('0.000'),
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'platform_fee': Decimal('0.000'),
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'platform_fee_percentage': Decimal('0.00'),
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'driver_amount': Decimal('0.000'),
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'error': 'No pricing rule found for this distance/weight combination.'
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}
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total_price = rule.price
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# 2. Calculate Fees
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profile = PlatformProfile.objects.first()
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fee_percentage = profile.platform_fee_percentage if profile else Decimal('0.00')
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platform_fee = total_price * (fee_percentage / Decimal('100.00'))
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driver_amount = total_price - platform_fee
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return {
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'price': total_price,
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'platform_fee': platform_fee,
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'platform_fee_percentage': fee_percentage,
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'driver_amount': driver_amount
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}
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