const express = require('express');
const { initDb, getAllArticles, getArticle, createArticle, updateArticle, deleteArticle, searchArticles } = require('./db');
const app = express();
const cors = require('cors');
const PORT = 9000;

app.use(cors())
app.use(express.json());

initDb().then(() => {

    app.get('/', (req, res) => {
        res.json({message : 'Server is running'});
    });

    app.get('/api/articles', (req, res) => {
        try {
            const articles = getAllArticles();
            res.json(articles);
        } catch (error) {
            console.error('Error fetching articles:', error);
            res.status(500).json({error: 'Failed to fetch articles', 'details': String(error)});
        }
    });

    app.get('/api/articles/:ka_number', (req, res) => {
        try {
            const article = getArticle(req.params.ka_number);

            if (!article) {
                return res.status(404).json({ error: 'Article not found' });
            }

            res.json(article);
        } catch (error) {
            console.error('Error fetching article:', error);
            res.status(500).json({error: 'Failed to fetch article', 'details': String(error)});
        }
    });

    app.post('/api/articles', (req, res) => {
        try {
            const { title, content } = req.body;

            if (!title) {
                return res.status(400).json({error: 'Title is required' });
            }

            const article = createArticle(title, content || '');
            res.status(201).json(article);

        } catch (error) {
            console.error('Error creating article:', error);
            res.status(500).json({error: 'Failed to create article', 'details': String(error)});
        }
    });

    app.put('/api/articles/:ka_number', (req, res) => {
        try {
            const { title, content } = req.body;

            if (!title) {
                return res.status(400).json({error: 'Title is required' });
            }

            const article = updateArticle(req.params.ka_number, title, content);

            if (!article) {
                return res.status(404).json({error: 'Article not found'});
            }

            res.json(article);
        } catch (error) {
            console.error('Error updating article:', error);
            return res.status(500).json({error: 'Error while updating article', 'details': String(error)});
        }
    });

    app.delete('/api/articles/:ka_number', (req, res) => {
        try {
            deleteArticle(req.params.ka_number);
            return res.status(200).json({'message': 'Successfully deleted article'});

        } catch (error) {
            console.error('Error when deleting article:', error);
            return res.status(500).json({error: 'Failed to delete article', 'details': String(error)});
        }
    });

    app.get('/api/search', (req, res) => {
        try {
            const query = req.query.q;

            if (!query) {
                return res.status(400).json({error: 'Search query is required'});
            }

            const results = searchArticles(query);
            res.json(results);
        } catch (error) {
            console.error('Error when searching articles:', error);
            return res.status(500).json({error: 'Failed to search articles', 'details': String(error)});
        }
    });

    app.listen(PORT, () => {
        console.log(`Server running on http://localhost:${PORT}`);
    });
}).catch(err => {
    console.error('Failed to initialize database:', err);
});