import { getUserIdFromSession } from '../../utils/auth';
import { PLANTING_COST, isCropGrown } from '../../utils/village';
import { CropType } from '@prisma/client';

// --- Handler ---
export default defineEventHandler(async (event) => {
    const userId = await getUserIdFromSession(event);
    const { fieldId, cropType } = await readBody(event);

    // 1. --- Validation ---
    if (typeof fieldId !== 'number' || !cropType) {
        throw createError({ statusCode: 400, statusMessage: 'Invalid request body. "fieldId" and "cropType" are required.' });
    }
    if (!Object.values(CropType).includes(cropType)) {
        throw createError({ statusCode: 400, statusMessage: 'Invalid crop type.' });
    }

    // 2. --- Find the target field and validate its state ---
    const field = await prisma.villageObject.findFirst({
        where: {
            id: fieldId,
            type: 'FIELD',
            village: { userId: userId }, // Ensures ownership
        },
    });

    if (!field) {
        throw createError({ statusCode: 404, statusMessage: 'Field not found or you do not own it.' });
    }

    if (field.cropType !== null) {
        throw createError({ statusCode: 409, statusMessage: 'A crop is already planted in this field.' });
    }

    // 3. --- Perform atomic transaction ---
    try {
        const [, updatedField] = await prisma.$transaction([
            prisma.user.update({
                where: { id: userId, coins: { gte: PLANTING_COST } },
                data: { coins: { decrement: PLANTING_COST } },
            }),
            prisma.villageObject.update({
                where: { id: fieldId },
                data: {
                    cropType: cropType,
                    plantedAt: new Date(),
                },
            }),
        ]);

        return {
            id: updatedField.id,
            type: updatedField.type,
            x: updatedField.x,
            y: updatedField.y,
            cropType: updatedField.cropType,
            isGrown: isCropGrown(updatedField.plantedAt, updatedField.cropType), // will be false
        };

    } catch (e) {
        throw createError({ statusCode: 402, statusMessage: 'Insufficient coins to plant seeds.' });
    }
});