use crate::model;
use crate::state;
use axum::extract::ws::Message;
use rand::distributions::Alphanumeric;
use rand::{Rng, thread_rng};
use sqlx::{Row, SqlitePool};
use std::io::Cursor;

// Utility functions
pub fn generate_token() -> String {
    thread_rng()
        .sample_iter(&Alphanumeric)
        .take(32)
        .map(char::from)
        .collect()
}

pub async fn verify_token(pool: &SqlitePool, token: &str) -> Result<Option<String>, sqlx::Error> {
    let result = sqlx::query(
        "SELECT username FROM sessions WHERE token = ? AND expires_at > datetime('now')",
    )
    .bind(token)
    .fetch_optional(pool)
    .await?;

    Ok(result.map(|row| row.get("username")))
}

pub async fn mark_messages_as_read(
    pool: &SqlitePool,
    from_user: &str,
    to_user: &str,
) -> Result<(), sqlx::Error> {
    let result = sqlx::query(
        "UPDATE messages SET read = TRUE WHERE from_user = ? AND to_user = ? AND read = FALSE AND deleted_for_everyone = FALSE"
    )
    .bind(from_user)
    .bind(to_user)
    .execute(pool)
    .await?;

    println!(
        "✅ Marked {} messages as read from {} to {}",
        result.rows_affected(),
        from_user,
        to_user
    );
    Ok(())
}

// Process and resize avatar
pub async fn process_avatar(data: &[u8]) -> Result<Vec<u8>, String> {
    // Load image
    let img = match image::load_from_memory(data) {
        Ok(img) => img,
        Err(_) => return Err("Invalid image format".to_string()),
    };

    // Resize image to 150x150 pixels
    let resized = img.resize_to_fill(150, 150, image::imageops::FilterType::Lanczos3);

    // Convert to JPEG
    let mut jpeg_data = Vec::new();
    match resized.write_to(&mut Cursor::new(&mut jpeg_data), image::ImageFormat::Jpeg) {
        Ok(_) => Ok(jpeg_data),
        Err(_) => Err("Error processing image".to_string()),
    }
}

pub async fn get_message_history(
    pool: &SqlitePool,
    username: &str,
    other_user: &str,
) -> Result<Vec<model::ChatMessage>, sqlx::Error> {
    // Если указан конкретный собеседник, помечаем сообщения как прочитанные
    if !other_user.is_empty() {
        mark_messages_as_read(pool, other_user, username).await?;
    }

    let query = if other_user.is_empty() {
        // Получаем все сообщения пользователя (исключая удаленные)
        r#"
        SELECT id, from_user, to_user, content, timestamp, message_type
        FROM messages
        WHERE (from_user = ? OR to_user = ?)
        AND deleted_for_everyone = FALSE
        AND ((from_user = ? AND deleted_for_sender = FALSE) OR (to_user = ? AND deleted_for_receiver = FALSE))
        ORDER BY timestamp
        "#
    } else {
        // Получаем сообщения только с конкретным пользователем (исключая удаленные)
        r#"
        SELECT id, from_user, to_user, content, timestamp, message_type
        FROM messages
        WHERE ((from_user = ? AND to_user = ?) OR (from_user = ? AND to_user = ?))
        AND deleted_for_everyone = FALSE
        AND ((from_user = ? AND deleted_for_sender = FALSE) OR (to_user = ? AND deleted_for_receiver = FALSE))
        ORDER BY timestamp
        "#
    };

    let rows = if other_user.is_empty() {
        sqlx::query(query)
            .bind(username)
            .bind(username)
            .bind(username)
            .bind(username)
            .fetch_all(pool)
            .await?
    } else {
        sqlx::query(query)
            .bind(username)
            .bind(other_user)
            .bind(other_user)
            .bind(username)
            .bind(username)
            .bind(username)
            .fetch_all(pool)
            .await?
    };

    let mut messages = Vec::new();
    for row in rows {
        let message = model::ChatMessage {
            id: row.get("id"),
            from_user: row.get("from_user"),
            to_user: row.get("to_user"),
            content: row.get("content"),
            timestamp: row.get("timestamp"),
            message_type: row.get("message_type"),
        };
        messages.push(message);
    }

    Ok(messages)
}

pub async fn broadcast_user_list(users: &state::UserMap) {
    let user_list: Vec<String> = users.read().await.keys().cloned().collect();
    let user_list_msg = serde_json::json!({
        "type": "user_list",
        "users": user_list
    });

    for tx in users.read().await.values() {
        let _ = tx.send(Message::Text(user_list_msg.to_string()));
    }
}

pub async fn save_message(pool: &SqlitePool, msg: &model::ChatMessage) -> Result<(), sqlx::Error> {
    sqlx::query(
        "INSERT OR REPLACE INTO messages (id, from_user, to_user, content, timestamp, message_type) VALUES (?, ?, ?, ?, ?, ?)",
    )
    .bind(&msg.id)
    .bind(&msg.from_user)
    .bind(&msg.to_user)
    .bind(&msg.content)
    .bind(msg.timestamp)
    .bind(&msg.message_type)
    .execute(pool)
    .await?;

    Ok(())
}