#!/bin/bash
set -euo pipefail

usage() {
  echo "Usage: $0 [project-name]"
  echo "If no project name is given, you will be prompted."
}

valid_name() {
  [[ "$1" =~ ^[A-Za-z0-9_-]+$ ]]
}

if [[ "${1-}" == "-h" || "${1-}" == "--help" ]]; then
  usage; exit 0
fi

PROJ="${1-}"

if [[ -n "$PROJ" ]] && ! valid_name "$PROJ"; then
  echo "Invalid project name: $PROJ (use letters, numbers, hyphen, underscore)"
  PROJ=""
fi

while [[ -z "$PROJ" ]]; do
  read -r -p "Enter project name (letters, numbers, -, _ only): " PROJ
  if [[ -z "$PROJ" ]]; then
    continue
  fi
  if ! valid_name "$PROJ"; then
    echo "Invalid project name. Use letters, numbers, hyphen, underscore."
    PROJ=""
  fi
done

echo ">> Creating Tauri+React+FastAPI boilerplate in '$PROJ' ..."

# --- Directory Structure ---
mkdir -p "$PROJ/backend"
mkdir -p "$PROJ/frontend"

# --- Backend: Python FastAPI+SQLite ---
cat > "$PROJ/backend/requirements.txt" <<EOF
fastapi
uvicorn[standard]
EOF

cat > "$PROJ/backend/db.py" <<EOF
import sqlite3, os
from datetime import datetime

DB_FILE = os.environ.get("WS_DB_PATH", "appdata.db")

def get_conn():
    conn = sqlite3.connect(DB_FILE, check_same_thread=False)
    conn.row_factory = sqlite3.Row
    return conn

def init_db():
    conn = get_conn()
    c = conn.cursor()
    c.execute('''
    CREATE TABLE IF NOT EXISTS likes (
        id TEXT PRIMARY KEY,
        title TEXT,
        artist TEXT,
        album TEXT,
        url TEXT,
        duration INTEGER,
        is_new INTEGER DEFAULT 1,
        last_seen TIMESTAMP
    )''')
    conn.commit()
    conn.close()

def get_likes(is_new=None):
    conn = get_conn()
    c = conn.cursor()
    if is_new is None:
        rows = c.execute('SELECT * FROM likes ORDER BY last_seen DESC').fetchall()
    else:
        rows = c.execute('SELECT * FROM likes WHERE is_new=? ORDER BY last_seen DESC', (1 if is_new else 0,)).fetchall()
    return [dict(row) for row in rows]

def add_demo_like():
    conn = get_conn()
    c = conn.cursor()
    c.execute(
        "INSERT OR IGNORE INTO likes (id, title, artist, album, url, duration, last_seen) VALUES (?, ?, ?, ?, ?, ?, ?)",
        ("track1", "Test Track", "Some Artist", "Test Album", "http://test", 123, datetime.utcnow())
    )
    conn.commit()
    conn.close()
EOF

cat > "$PROJ/backend/main.py" <<EOF
from fastapi import FastAPI, WebSocket
from fastapi.middleware.cors import CORSMiddleware
from starlette.websockets import WebSocketDisconnect
import db

app = FastAPI(title="$PROJ – React, FastAPI, SQLite, WebSocket")
db.init_db()
db.add_demo_like()

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_methods=["*"],
    allow_headers=["*"],
)

@app.get("/likes/all")
def api_all_likes():
    return db.get_likes()

@app.get("/likes/new")
def api_new_likes():
    return db.get_likes(is_new=True)

# Example WebSocket endpoint (send a message on connection)
@app.websocket("/ws")
async def websocket_endpoint(ws: WebSocket):
    await ws.accept()
    try:
        await ws.send_json({"type": "hello", "msg": "WebSocket is live!"})
        while True:
            data = await ws.receive_text()
            await ws.send_json({"type": "echo", "data": data})
    except WebSocketDisconnect:
        # Client disconnected; exit quietly.
        pass
    except Exception:
        # Any other exception: close connection gracefully.
        await ws.close()
EOF

# --- Frontend: Vite+React+ESLint+Tauri ---
cd "$PROJ/frontend"
CI=true npm_config_yes=true npm create vite@5.2.0 . -- --template react

# Patch package.json for Tauri & deps
node -e '
const fs = require("fs");
const pkg = JSON.parse(fs.readFileSync("./package.json", "utf8"));
pkg.scripts = {
  ...pkg.scripts,
  tauri: "tauri",
  "tauri-dev": "tauri dev",
  "tauri-build": "tauri build"
};
pkg.dependencies = pkg.dependencies || {};
pkg.devDependencies = pkg.devDependencies || {};
pkg.dependencies.axios = pkg.dependencies.axios || "latest";
pkg.dependencies["@tauri-apps/api"] = pkg.dependencies["@tauri-apps/api"] || "latest";
pkg.devDependencies["@tauri-apps/cli"] = pkg.devDependencies["@tauri-apps/cli"] || "latest";
pkg.devDependencies["eslint-plugin-react"] = pkg.devDependencies["eslint-plugin-react"] || "latest";
fs.writeFileSync("package.json", JSON.stringify(pkg, null, 2));
'

# Tauri config and Rust backend
mkdir -p src-tauri/src
mkdir -p src-tauri/icons

PROJ="$PROJ" python3 - <<'PY'
import json, os, re, pathlib
proj = os.environ["PROJ"]
identifier = "com.example." + (re.sub(r"[^A-Za-z0-9]", "", proj) or "app")
cfg = {
    "$schema": "https://schema.tauri.app/config/2",
    "productName": proj,
    "version": "0.1.0",
    "identifier": identifier,
    "build": {
        "beforeDevCommand": "npm run dev",
        "beforeBuildCommand": "npm run build",
        "devUrl": "http://localhost:5173",
        "frontendDist": "../dist",
    },
    "app": {
        "windows": [
            {
                "title": f"{proj} – React, FastAPI, SQLite, WebSocket, ESLint",
                "width": 1200,
                "height": 800,
            }
        ],
        "security": {"csp": None},
    },
    "bundle": {"active": True, "targets": "all"},
}
pathlib.Path("src-tauri/tauri.conf.json").write_text(json.dumps(cfg, indent=2))
PY

cat > src-tauri/Cargo.toml <<'EOF'
[package]
name = "tauri-react-fastapi-app"
version = "0.1.0"
description = "Tauri + React + FastAPI boilerplate"
authors = ["You"]
edition = "2021"
build = "build.rs"

[build-dependencies]
tauri-build = { version = "2", features = [] }

[dependencies]
tauri = { version = "2", features = [] }
serde = { version = "1", features = ["derive"] }
serde_json = "1"

[features]
default = []
EOF

cat > src-tauri/build.rs <<'EOF'
fn main() {
    tauri_build::build()
}
EOF

cat > src-tauri/src/main.rs <<'EOF'
#![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]

fn main() {
    tauri::Builder::default()
        .run(tauri::generate_context!())
        .expect("error while running tauri application");
}
EOF

# Minimal 32x32 RGBA icon required by Tauri bundle tooling
python3 - <<'PY'
import pathlib, struct, zlib
path = pathlib.Path("src-tauri/icons/icon.png")
path.parent.mkdir(parents=True, exist_ok=True)
w = h = 32
color = (48, 160, 255, 255)  # rgba blue-ish
row = bytes([0]) + bytes(color) * w  # filter byte + pixels
data = row * h

def chunk(t, d):
    return (struct.pack("!I", len(d)) + t + d +
            struct.pack("!I", zlib.crc32(t + d) & 0xFFFFFFFF))

ihdr = chunk(b'IHDR', struct.pack("!IIBBBBB", w, h, 8, 6, 0, 0, 0))
idat = chunk(b'IDAT', zlib.compress(data, 9))
iend = chunk(b'IEND', b'')
png = b'\x89PNG\r\n\x1a\n' + ihdr + idat + iend
path.write_bytes(png)
PY

cd src

cat > App.jsx <<'EOF'
import React, { useEffect, useState } from "react";
import axios from "axios";

const API_URL = "http://localhost:8000";

function App() {
  const [allLikes, setAllLikes] = useState([]);
  const [wsMsg, setWsMsg] = useState("");
  const [error, setError] = useState("");
  const [wsAttempts, setWsAttempts] = useState(0);

  useEffect(() => {
    axios.get(API_URL + "/likes/all")
      .then(res => setAllLikes(res.data))
      .catch(err => setError(err.message));

    let socket;
    let retryTimer;

    const connectWs = (attempt = 0) => {
      setWsAttempts(attempt + 1);
      socket = new WebSocket("ws://localhost:8000/ws");
      socket.onopen = () => {
        setError("");
      };
      socket.onmessage = e => {
        const msg = JSON.parse(e.data);
        setWsMsg(JSON.stringify(msg));
      };
      socket.onerror = () => {
        setError("WebSocket connection failed");
      };
      socket.onclose = () => {
        if (attempt < 4) {
          retryTimer = setTimeout(() => connectWs(attempt + 1), 1000 * (attempt + 1));
        }
      };
    };

    connectWs();

    return () => {
      if (retryTimer) clearTimeout(retryTimer);
      if (socket) socket.close();
    };
  }, []);

  return (
    <div>
      <h1>React · FastAPI · SQLite · WebSocket · ESLint</h1>
      {error && <p style={{ color: "#f66" }}>Error: {error}</p>}
      <p>Likes from backend:</p>
      <ul>
        {allLikes.map(t => (
          <li key={t.id}>{t.title} – {t.artist}</li>
        ))}
      </ul>
      <p>WebSocket (attempt {wsAttempts}): <code>{wsMsg}</code></p>
    </div>
  );
}
export default App;
EOF

cat > main.jsx <<'EOF'
import React from 'react'
import { createRoot } from 'react-dom/client'
import App from './App.jsx'

createRoot(document.getElementById('root')).render(
  <React.StrictMode>
    <App />
  </React.StrictMode>,
)
EOF

cat > index.css <<'EOF'
body { font-family: sans-serif; margin: 2em; background: #202126; color: #fafafa; }
h1 { color: #6bf; }
EOF

cd ../

cd ../..

cat > "$PROJ/.gitignore" <<'EOF'
backend/.venv
backend/__pycache__/
backend/appdata.db
frontend/node_modules
frontend/dist
frontend/src-tauri/target
frontend/src-tauri/gen
frontend/src-tauri/Cargo.lock
.DS_Store
*.pyc
EOF

cat > "$PROJ/run.sh" <<'EOF'
#!/bin/bash
set -euo pipefail

ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
BACKEND="$ROOT/backend"
FRONTEND="$ROOT/frontend"
VENV="$BACKEND/.venv"

cleanup() {
  [[ -n "${BACK_PID:-}" ]] && kill "$BACK_PID" 2>/dev/null || true
}
trap cleanup EXIT INT TERM

echo ">> Backend: ensure venv and deps"
python3 -m venv "$VENV"
source "$VENV/bin/activate"
pip install --upgrade pip
pip install -r "$BACKEND/requirements.txt"

echo ">> Starting backend (uvicorn)..."
cd "$BACKEND"
python -m uvicorn main:app --port 8000 --reload &
BACK_PID=$!

echo ">> Installing frontend deps (npm install)..."
cd "$FRONTEND"
npm install

echo ">> Launching Tauri dev (opens a window)..."
npm run tauri-dev
EOF
chmod +x "$PROJ/run.sh"

cat > "$PROJ/README.md" <<EOF
# $PROJ

## Quickstart (dev)

1. **Backend venv + deps**
   cd $PROJ/backend
   python3 -m venv .venv
   source .venv/bin/activate
   pip install --upgrade pip
   pip install -r requirements.txt

2. **Install frontend deps**
   cd ../frontend
   npm install

3. **Run Tauri (dev)**
   npm run tauri-dev

- **Alt: run both servers and Tauri via helper**
  ./run.sh

## What this does

- Starts FastAPI backend (REST & WebSocket, SQLite)
- Starts React+Vite dev server (auto-reloads)
- Opens Tauri window
- React frontend talks to backend via HTTP+WebSocket

## Production-ish build

1. cd frontend
2. npm run build
3. npm run tauri-build

(Tauri will bundle the built frontend from dist/)

## WebSocket

Check out App.jsx and main.py for example WS code.

EOF

echo ">> Creating Python venv and installing backend requirements..."
cd "$PROJ/backend"
python3 -m venv .venv
source .venv/bin/activate
pip install --upgrade pip
pip install -r requirements.txt
deactivate

echo ">> Installing frontend npm dependencies..."
cd ../frontend
npm install
echo ">> All dependencies installed."
cd ../..

echo ">> Boilerplate created at '$PROJ'. See $PROJ/README.md for next steps."

echo ">> Launching Tauri app..."
cd "$PROJ/backend"
source .venv/bin/activate
python -m uvicorn main:app --port 8000 --reload &
BACK_PID=$!
trap 'kill $BACK_PID 2>/dev/null || true' EXIT
cd ../frontend
npm run tauri-dev