// main.go
package main

import (
    "database/sql"
    "encoding/json"
    "log"
    "net/http"

    _ "github.com/mattn/go-sqlite3"
)

type EmojiClick struct {
    PostID string `json:"post_id"`
    Emoji  string `json:"emoji"`
}

func main() {
    // Connect to the SQLite database
    db, err := sql.Open("sqlite3", "./emoji_counter.db")
    if err != nil {
        log.Fatal(err)
    }
    defer db.Close()

    // Execute schema SQL to create tables
    schema := `CREATE TABLE IF NOT EXISTS emoji_clicks (
        id INTEGER PRIMARY KEY AUTOINCREMENT,
        post_id TEXT NOT NULL,
        emoji TEXT NOT NULL,
        created_at DATETIME DEFAULT CURRENT_TIMESTAMP
    );`
    _, err = db.Exec(schema)
    if err != nil {
        log.Fatal(err)
    }

    // Define the HTTP handler for emoji clicks
    http.HandleFunc("/emoji-click", func(w http.ResponseWriter, r *http.Request) {
        if r.Method != http.MethodPost {
            http.Error(w, "Invalid request method", http.StatusMethodNotAllowed)
            return
        }

        var emojiClick EmojiClick
        if err := json.NewDecoder(r.Body).Decode(&emojiClick); err != nil {
            http.Error(w, "Bad request", http.StatusBadRequest)
            return
        }

        _, err := db.Exec("INSERT INTO emoji_clicks (post_id, emoji) VALUES (?, ?)", emojiClick.PostID, emojiClick.Emoji)
        if err != nil {
            http.Error(w, "Failed to save emoji click", http.StatusInternalServerError)
            return
        }

        w.WriteHeader(http.StatusOK)
    })

    // Define the HTTP handler for getting emoji counts
    http.HandleFunc("/emoji-counts", func(w http.ResponseWriter, r *http.Request) {
        postID := r.URL.Query().Get("post_id")
        if postID == "" {
            http.Error(w, "post_id is required", http.StatusBadRequest)
            return
        }

        rows, err := db.Query("SELECT emoji, COUNT(*) as count FROM emoji_clicks WHERE post_id = ? GROUP BY emoji", postID)
        if err != nil {
            http.Error(w, "Failed to get emoji counts", http.StatusInternalServerError)
            return
        }
        defer rows.Close()

        emojiCounts := make(map[string]int)
        for rows.Next() {
            var emoji string
            var count int
            if err := rows.Scan(&emoji, &count); err != nil {
                http.Error(w, "Failed to parse emoji counts", http.StatusInternalServerError)
                return
            }
            emojiCounts[emoji] = count
        }

        if err := json.NewEncoder(w).Encode(emojiCounts); err != nil {
            http.Error(w, "Failed to encode response", http.StatusInternalServerError)
            return
        }
    })

    // Start the HTTP server
    log.Println("Starting server on :8080")
    log.Fatal(http.ListenAndServe(":8080", nil))
}