const express = require("express");
const { connect, toId, serialize } = require("../db");

const router = express.Router();

router.get("/", async (req, res) => {
  const db = await connect();
  const projects = await db.collection("projects").find().sort({ name: 1 }).toArray();
  res.json(projects.map(serialize));
});

router.post("/", async (req, res) => {
  const { name, description, color } = req.body;
  if (!name || typeof name !== "string") {
    return res.status(400).json({ error: "name ist erforderlich" });
  }
  const db = await connect();
  const doc = {
    name,
    description: description || "",
    color: color || "#3E5C50"
  };
  const result = await db.collection("projects").insertOne(doc);
  res.status(201).json(serialize({ _id: result.insertedId, ...doc }));
});

router.put("/:id", async (req, res) => {
  const _id = toId(req.params.id);
  if (!_id) return res.status(404).json({ error: "Projekt nicht gefunden" });

  const { name, description, color } = req.body;
  const update = {};
  if (name !== undefined) update.name = name;
  if (description !== undefined) update.description = description;
  if (color !== undefined) update.color = color;

  const db = await connect();
  const updated = await db
    .collection("projects")
    .findOneAndUpdate({ _id }, { $set: update }, { returnDocument: "after" });

  if (!updated) return res.status(404).json({ error: "Projekt nicht gefunden" });
  res.json(serialize(updated));
});

router.delete("/:id", async (req, res) => {
  const _id = toId(req.params.id);
  if (!_id) return res.status(404).json({ error: "Projekt nicht gefunden" });

  const db = await connect();
  const result = await db.collection("projects").deleteOne({ _id });
  if (result.deletedCount === 0) {
    return res.status(404).json({ error: "Projekt nicht gefunden" });
  }
  await db.collection("tasks").deleteMany({ projectId: req.params.id });
  res.status(204).end();
});

module.exports = router;