app.py

"""
app.py — Flask API for FYP Dashboard
Serves precomputed_data.json generated by analyze.py

Endpoints:
  GET /api/summary       → summary stats (cards)
  GET /api/titles        → top job titles + salary by title
  GET /api/skills        → top skills, skills by title, optimal skills
  GET /api/trends        → salary trends + skill trends over time
  GET /api/location      → remote breakdown + top countries
  GET /api/all           → everything in one call (used by dashboard)
"""

import json
import os
from flask import Flask, jsonify
from flask_cors import CORS

app = Flask(__name__)

# Allow your Vercel frontend domain — update this after deploying
CORS(app, origins=[
    "http://localhost:3000",       # local dev
    "https://*.vercel.app",        # any vercel preview
])

# ─────────────────────────────────────────────
# Load precomputed data once at startup
# ─────────────────────────────────────────────
DATA_PATH = os.path.join(os.path.dirname(__file__), "precomputed_data.json")

def load_data():
    if not os.path.exists(DATA_PATH):
        raise FileNotFoundError(
            f"precomputed_data.json not found at {DATA_PATH}\n"
            "Run analyze.py first to generate it."
        )
    with open(DATA_PATH, "r") as f:
        return json.load(f)

try:
    DATA = load_data()
    print(f"[OK] Loaded precomputed data")
    print(f"     Generated at: {DATA['meta']['generated_at']}")
    print(f"     Total rows: {DATA['meta']['total_rows_processed']:,}")
except FileNotFoundError as e:
    print(f"[ERROR] {e}")
    DATA = None


def data_required(fn):
    """Decorator — returns 503 if data not loaded."""
    from functools import wraps
    @wraps(fn)
    def wrapper(*args, **kwargs):
        if DATA is None:
            return jsonify({
                "error": "Data not ready. Run analyze.py first."
            }), 503
        return fn(*args, **kwargs)
    return wrapper


# ─────────────────────────────────────────────
# Routes
# ─────────────────────────────────────────────

@app.route("/", methods=["GET"])
def index():
    if DATA is None:
        return jsonify({"status": "error", "message": "Run analyze.py first"}), 503
    return jsonify({
        "status": "ok",
        "generated_at": DATA["meta"]["generated_at"],
        "total_rows": DATA["meta"]["total_rows_processed"],
        "endpoints": [
            "/api/summary",
            "/api/titles",
            "/api/skills",
            "/api/trends",
            "/api/location",
            "/api/all",
        ]
    })


@app.route("/api/summary", methods=["GET"])
@data_required
def get_summary():
    return jsonify(DATA["summary_stats"])


@app.route("/api/titles", methods=["GET"])
@data_required
def get_titles():
    return jsonify({
        "top_titles": DATA["top_titles"],
        "salary_by_title": DATA["salary_by_title"],
    })


@app.route("/api/skills", methods=["GET"])
@data_required
def get_skills():
    return jsonify({
        "top_skills": DATA["top_skills"],
        "skills_by_title": DATA["skills_by_title"],
        "optimal_skills": DATA["optimal_skills"],
    })


@app.route("/api/trends", methods=["GET"])
@data_required
def get_trends():
    return jsonify({
        "salary_trends": DATA["salary_trends"],
        "skill_trends": DATA["skill_trends"],
    })


@app.route("/api/location", methods=["GET"])
@data_required
def get_location():
    return jsonify({
        "remote_breakdown": DATA["remote_breakdown"],
        "top_countries": DATA["top_countries"],
    })


@app.route("/api/all", methods=["GET"])
@data_required
def get_all():
    """Single endpoint — dashboard calls this once on load."""
    return jsonify(DATA)


# ─────────────────────────────────────────────
# Run
# ─────────────────────────────────────────────
if __name__ == "__main__":
    port = int(os.environ.get("PORT", 7860))
    debug = os.environ.get("FLASK_ENV") != "production"
    print(f"Starting Flask on port {port} (debug={debug})")
    app.run(host="0.0.0.0", port=port, debug=debug)