api-v1/routes/locationRoutes.js

import express from "express";
import pool from "../db/pool.js";

const router = express.Router();

// 1. CREATE Location
router.post("/", async (req, res) => {
	const client = await pool.connect();
	try {
		await client.query("BEGIN");

		const {
			user_id,
			lat,
			lng,
			source_type,
			source_confidence,
			selected_location,
			is_saved_address,
			location_type,
			country,
			state,
			district,
			city_village,
			pincode,
		} = req.body;

		// Validate user exists if this is a saved address
		let finalUserId = user_id;
		if (is_saved_address && user_id) {
			const userCheck = await client.query("SELECT id FROM users WHERE id = $1 AND deleted = FALSE", [user_id]);
			if (userCheck.rows.length === 0) {
				await client.query("ROLLBACK");
				return res.status(400).json({ 
					error: `User with id ${user_id} does not exist. Cannot create saved address for non-existent user.` 
				});
			}
		} else if (!is_saved_address) {
			// For captured locations (not saved addresses), user_id can be NULL
			finalUserId = null;
		} else if (is_saved_address && !user_id) {
			await client.query("ROLLBACK");
			return res.status(400).json({ 
				error: "user_id is required when is_saved_address is true" 
			});
		}

		// 1. Insert into locations
		const insertLocationQuery = `
            INSERT INTO locations (
                user_id, lat, lng, source_type, source_confidence, selected_location,
                is_saved_address, location_type, country, state, district, city_village, pincode
            )
            VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13)
            RETURNING *
        `;
		const locationValues = [
			finalUserId,
			lat,
			lng,
			source_type || "manual",
			source_confidence || "low",
			selected_location || false,
			is_saved_address || false,
			location_type || "other",
			country,
			state,
			district,
			city_village,
			pincode,
		];
		const locationResult = await client.query(insertLocationQuery, locationValues);

		await client.query("COMMIT");

		res.status(201).json({
			...locationResult.rows[0],
		});
	} catch (err) {
		await client.query("ROLLBACK");
		console.error("Error creating location:", err);
		
		// Provide more specific error messages
		if (err.code === '23503') { // Foreign key violation
			return res.status(400).json({ 
				error: `Foreign key constraint violation: ${err.detail || 'The provided user_id does not exist in the users table.'}` 
			});
		}
		
		res.status(500).json({ error: err.message || "Internal server error" });
	} finally {
		client.release();
	}
});

// 2. GET User Locations
router.get("/user/:userId", async (req, res) => {
	try {
		const { userId } = req.params;
		const queryText = `
            SELECT * FROM locations 
            WHERE user_id = $1 AND deleted = FALSE
            ORDER BY created_at DESC
        `;
		const result = await pool.query(queryText, [userId]);
		res.json(result.rows);
	} catch (err) {
		console.error("Error fetching user locations:", err);
		res.status(500).json({ error: "Internal server error" });
	}
});

// 3. GET Single Location
router.get("/:id", async (req, res) => {
	try {
		const { id } = req.params;
		const queryText = `
            SELECT * FROM locations 
            WHERE id = $1 AND deleted = FALSE
        `;
		const result = await pool.query(queryText, [id]);

		if (result.rows.length === 0) {
			return res.status(404).json({ error: "Location not found" });
		}

		res.json(result.rows[0]);
	} catch (err) {
		console.error("Error fetching location:", err);
		res.status(500).json({ error: "Internal server error" });
	}
});

// 4. UPDATE Location
router.put("/:id", async (req, res) => {
	try {
		const { id } = req.params;
		const {
			lat,
			lng,
			source_type,
            source_confidence,
            selected_location,
			is_saved_address,
			location_type,
			country,
			state,
			district,
			city_village,
			pincode,
		} = req.body;

		const updateQuery = `
            UPDATE locations 
            SET lat = COALESCE($1, lat),
                lng = COALESCE($2, lng),
                source_type = COALESCE($3, source_type),
                source_confidence = COALESCE($4, source_confidence),
                selected_location = COALESCE($5, selected_location),
                is_saved_address = COALESCE($6, is_saved_address),
                location_type = COALESCE($7, location_type),
                country = COALESCE($8, country),
                state = COALESCE($9, state),
                district = COALESCE($10, district),
                city_village = COALESCE($11, city_village),
                pincode = COALESCE($12, pincode)
            WHERE id = $13 AND deleted = FALSE
            RETURNING *
        `;
        
        const values = [
            lat, lng, source_type, source_confidence, selected_location,
            is_saved_address, location_type, country, state, district, city_village, pincode,
            id
        ];

		const result = await pool.query(updateQuery, values);

		if (result.rows.length === 0) {
			return res.status(404).json({ error: "Location not found" });
		}

		res.json(result.rows[0]);
	} catch (err) {
		console.error("Error updating location:", err);
		res.status(500).json({ error: "Internal server error" });
	}
});

// 5. DELETE Location
router.delete("/:id", async (req, res) => {
	try {
		const { id } = req.params;
		const queryText = `
            UPDATE locations 
            SET deleted = TRUE 
            WHERE id = $1 
            RETURNING id
        `;
		const result = await pool.query(queryText, [id]);

		if (result.rows.length === 0) {
			return res.status(404).json({ error: "Location not found" });
		}

		res.json({ message: "Location deleted successfully" });
	} catch (err) {
		console.error("Error deleting location:", err);
		res.status(500).json({ error: "Internal server error" });
	}
});

export default router;