// Claude Desktop — Wissensbasis (claude-db)
// Direkte MySQL-Anbindung zur zentralen Wissensdatenbank

use mysql_async::{Pool, prelude::*};
use serde::{Deserialize, Serialize};

/// Verbindungskonfiguration
const MYSQL_HOST: &str = "192.168.155.1";
const MYSQL_PORT: u16 = 3306;
const MYSQL_USER: &str = "claude";
const MYSQL_PASS: &str = "claude";
const MYSQL_DB: &str = "claude";

/// Wissenseintrag aus der knowledge-Tabelle
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct KnowledgeEntry {
    pub id: i64,
    pub category: String,
    pub title: String,
    pub content: String,
    pub tags: Option<String>,
    pub priority: i32,
    pub status: String,
    pub related_ids: Option<String>,
    pub source: Option<String>,
    pub created_at: String,
    pub updated_at: String,
}

/// Neuer Wissenseintrag (ohne id, timestamps)
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct NewKnowledge {
    pub category: String,
    pub title: String,
    pub content: String,
    pub tags: Option<String>,
    pub priority: Option<i32>,
    pub source: Option<String>,
}

/// Suchergebnis mit Relevanz-Score
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct SearchResult {
    pub entry: KnowledgeEntry,
    pub relevance: f64,
}

/// Verfügbare Kategorien
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CategoryInfo {
    pub name: String,
    pub count: i64,
}

// ============ Hilfsfunktionen ============

/// Erstellt einen MySQL Connection-Pool
fn create_pool() -> Pool {
    let url = format!(
        "mysql://{}:{}@{}:{}/{}",
        MYSQL_USER, MYSQL_PASS, MYSQL_HOST, MYSQL_PORT, MYSQL_DB
    );
    Pool::new(url.as_str())
}

// ============ Tauri Commands ============

/// Wissensbasis durchsuchen (Volltext)
#[tauri::command]
pub async fn search_knowledge(
    query: String,
    category: Option<String>,
    limit: Option<usize>,
) -> Result<Vec<SearchResult>, String> {
    let pool = create_pool();
    let mut conn = pool.get_conn().await.map_err(|e| e.to_string())?;

    let limit = limit.unwrap_or(20);

    // Volltext-Suche mit optionalem Kategorie-Filter
    let results: Vec<SearchResult> = if let Some(cat) = category {
        conn.exec_map(
            r#"SELECT
                id, category, title, content, tags, priority, status,
                related_ids, source, created_at, updated_at,
                MATCH(title, content, tags) AGAINST(? IN NATURAL LANGUAGE MODE) as relevance
            FROM knowledge
            WHERE MATCH(title, content, tags) AGAINST(? IN NATURAL LANGUAGE MODE)
            AND category = ?
            ORDER BY relevance DESC
            LIMIT ?"#,
            (&query, &query, &cat, limit),
            |(id, category, title, content, tags, priority, status, related_ids, source, created_at, updated_at, relevance):
             (i64, String, String, String, Option<String>, i32, String, Option<String>, Option<String>, String, String, f64)| {
                SearchResult {
                    entry: KnowledgeEntry {
                        id, category, title, content, tags, priority, status,
                        related_ids, source, created_at, updated_at,
                    },
                    relevance,
                }
            }
        ).await.map_err(|e| e.to_string())?
    } else {
        conn.exec_map(
            r#"SELECT
                id, category, title, content, tags, priority, status,
                related_ids, source, created_at, updated_at,
                MATCH(title, content, tags) AGAINST(? IN NATURAL LANGUAGE MODE) as relevance
            FROM knowledge
            WHERE MATCH(title, content, tags) AGAINST(? IN NATURAL LANGUAGE MODE)
            ORDER BY relevance DESC
            LIMIT ?"#,
            (&query, &query, limit),
            |(id, category, title, content, tags, priority, status, related_ids, source, created_at, updated_at, relevance):
             (i64, String, String, String, Option<String>, i32, String, Option<String>, Option<String>, String, String, f64)| {
                SearchResult {
                    entry: KnowledgeEntry {
                        id, category, title, content, tags, priority, status,
                        related_ids, source, created_at, updated_at,
                    },
                    relevance,
                }
            }
        ).await.map_err(|e| e.to_string())?
    };

    drop(conn);
    pool.disconnect().await.map_err(|e| e.to_string())?;

    println!("🔍 Wissensbasis-Suche '{}': {} Treffer", query, results.len());
    Ok(results)
}

/// Wissenseintrag nach ID laden
#[tauri::command]
pub async fn get_knowledge(id: i64) -> Result<Option<KnowledgeEntry>, String> {
    let pool = create_pool();
    let mut conn = pool.get_conn().await.map_err(|e| e.to_string())?;

    let result: Option<KnowledgeEntry> = conn.exec_first(
        r#"SELECT id, category, title, content, tags, priority, status,
           related_ids, source, created_at, updated_at
           FROM knowledge WHERE id = ?"#,
        (id,)
    ).await.map_err(|e| e.to_string())?
    .map(|(id, category, title, content, tags, priority, status, related_ids, source, created_at, updated_at):
          (i64, String, String, String, Option<String>, i32, String, Option<String>, Option<String>, String, String)| {
        KnowledgeEntry {
            id, category, title, content, tags, priority, status,
            related_ids, source, created_at, updated_at,
        }
    });

    drop(conn);
    pool.disconnect().await.map_err(|e| e.to_string())?;

    Ok(result)
}

/// Neuen Wissenseintrag speichern ("Das merken")
#[tauri::command]
pub async fn save_knowledge(entry: NewKnowledge) -> Result<i64, String> {
    let pool = create_pool();
    let mut conn = pool.get_conn().await.map_err(|e| e.to_string())?;

    let priority = entry.priority.unwrap_or(2);

    conn.exec_drop(
        r#"INSERT INTO knowledge (category, title, content, tags, priority, status, source, created_at, updated_at)
           VALUES (?, ?, ?, ?, ?, 'active', ?, NOW(), NOW())"#,
        (&entry.category, &entry.title, &entry.content, &entry.tags, priority, &entry.source)
    ).await.map_err(|e| e.to_string())?;

    let id: i64 = conn.last_insert_id().ok_or("Keine Insert-ID")? as i64;

    drop(conn);
    pool.disconnect().await.map_err(|e| e.to_string())?;

    println!("💾 Wissen gespeichert: {} (ID: {})", entry.title, id);
    Ok(id)
}

/// Alle Kategorien mit Anzahl der Einträge
#[tauri::command]
pub async fn get_knowledge_categories() -> Result<Vec<CategoryInfo>, String> {
    let pool = create_pool();
    let mut conn = pool.get_conn().await.map_err(|e| e.to_string())?;

    let categories: Vec<CategoryInfo> = conn.query_map(
        r#"SELECT category, COUNT(*) as count
           FROM knowledge
           WHERE status = 'active'
           GROUP BY category
           ORDER BY count DESC"#,
        |(name, count): (String, i64)| CategoryInfo { name, count }
    ).await.map_err(|e| e.to_string())?;

    drop(conn);
    pool.disconnect().await.map_err(|e| e.to_string())?;

    Ok(categories)
}

/// Letzte N Wissenseinträge laden
#[tauri::command]
pub async fn get_recent_knowledge(
    limit: Option<usize>,
    category: Option<String>,
) -> Result<Vec<KnowledgeEntry>, String> {
    let pool = create_pool();
    let mut conn = pool.get_conn().await.map_err(|e| e.to_string())?;

    let limit = limit.unwrap_or(10);

    let entries: Vec<KnowledgeEntry> = if let Some(cat) = category {
        conn.exec_map(
            r#"SELECT id, category, title, content, tags, priority, status,
               related_ids, source, created_at, updated_at
               FROM knowledge
               WHERE status = 'active' AND category = ?
               ORDER BY updated_at DESC
               LIMIT ?"#,
            (&cat, limit),
            |(id, category, title, content, tags, priority, status, related_ids, source, created_at, updated_at):
             (i64, String, String, String, Option<String>, i32, String, Option<String>, Option<String>, String, String)| {
                KnowledgeEntry {
                    id, category, title, content, tags, priority, status,
                    related_ids, source, created_at, updated_at,
                }
            }
        ).await.map_err(|e| e.to_string())?
    } else {
        conn.exec_map(
            r#"SELECT id, category, title, content, tags, priority, status,
               related_ids, source, created_at, updated_at
               FROM knowledge
               WHERE status = 'active'
               ORDER BY updated_at DESC
               LIMIT ?"#,
            (limit,),
            |(id, category, title, content, tags, priority, status, related_ids, source, created_at, updated_at):
             (i64, String, String, String, Option<String>, i32, String, Option<String>, Option<String>, String, String)| {
                KnowledgeEntry {
                    id, category, title, content, tags, priority, status,
                    related_ids, source, created_at, updated_at,
                }
            }
        ).await.map_err(|e| e.to_string())?
    };

    drop(conn);
    pool.disconnect().await.map_err(|e| e.to_string())?;

    Ok(entries)
}

/// Verbindung zur Wissensbasis testen
#[tauri::command]
pub async fn test_knowledge_connection() -> Result<String, String> {
    let pool = create_pool();
    let mut conn = pool.get_conn().await.map_err(|e| format!("Verbindungsfehler: {}", e))?;

    let count: i64 = conn.query_first("SELECT COUNT(*) FROM knowledge")
        .await
        .map_err(|e| e.to_string())?
        .unwrap_or(0);

    drop(conn);
    pool.disconnect().await.map_err(|e| e.to_string())?;

    println!("✅ Wissensbasis verbunden: {} Einträge", count);
    Ok(format!("Verbunden! {} Einträge in der Wissensbasis", count))
}