use ai::{
    error::{AiError, AiResult},
    tool::tools::FunctionCall,
};
use async_trait::async_trait;
use chrono::Utc;
use db::sqlx;
use serde_json::{json, Value};
use tracing::info;
use uuid::Uuid;

use super::run::AppAgentContext;
use crate::error::AppError;
use crate::AppService;
pub struct SaveMemoryTool;

impl SaveMemoryTool {
    pub fn new() -> Self {
        Self
    }
}

impl Default for SaveMemoryTool {
    fn default() -> Self {
        Self::new()
    }
}

#[async_trait]
impl FunctionCall for SaveMemoryTool {
    type Context = AppAgentContext;

    fn name(&self) -> &'static str {
        "save_memory"
    }

    fn schema(&self) -> Value {
        json!({
            "type": "object",
            "properties": {
                "key": {
                    "type": "string",
                    "description": "A short, descriptive key for the memory (e.g. 'user_preference_language', 'project_architecture')"
                },
                "value": {
                    "type": "string",
                    "description": "The information to remember"
                },
                "importance": {
                    "type": "integer",
                    "description": "Importance level 0-10 (10 = most important). Default: 5",
                    "minimum": 0,
                    "maximum": 10
                }
            },
            "required": ["key", "value"]
        })
    }

    async fn call(
        &self,
        context: &mut Self::Context,
        args: Value,
    ) -> AiResult<Value> {
        let key = args
            .get("key")
            .and_then(|v| v.as_str())
            .ok_or_else(|| AiError::Config("key parameter is required".to_string()))?;

        let value = args
            .get("value")
            .and_then(|v| v.as_str())
            .ok_or_else(|| AiError::Config("value parameter is required".to_string()))?;

        let importance = args
            .get("importance")
            .and_then(|v| v.as_i64())
            .unwrap_or(5)
            .clamp(0, 10) as i32;

        context.pending_memories.push(PendingMemory {
            key: key.to_string(),
            value: value.to_string(),
            importance,
        });

        Ok(json!({
            "success": true,
            "key": key,
            "message": format!("Memory '{}' saved (importance: {})", key, importance)
        }))
    }
}
pub struct RecallMemoryTool {
    memories_json: String,
}

impl RecallMemoryTool {
    pub fn new(memories_json: String) -> Self {
        Self { memories_json }
    }
}

#[async_trait]
impl FunctionCall for RecallMemoryTool {
    type Context = AppAgentContext;

    fn name(&self) -> &'static str {
        "recall_memory"
    }

    fn schema(&self) -> Value {
        json!({
            "type": "object",
            "properties": {
                "query": {
                    "type": "string",
                    "description": "Optional search query to filter memories by key or content"
                }
            }
        })
    }

    async fn call(
        &self,
        _context: &mut Self::Context,
        args: Value,
    ) -> AiResult<Value> {
        let query = args
            .get("query")
            .and_then(|v| v.as_str())
            .unwrap_or("");

        if query.is_empty() {
            return Ok(json!({
                "memories": self.memories_json,
                "count": "all"
            }));
        }

        Ok(json!({
            "memories": self.memories_json,
            "query": query,
            "hint": "Search the memories above for matches to your query"
        }))
    }
}
#[derive(Debug, Clone)]
pub struct PendingMemory {
    pub key: String,
    pub value: String,
    pub importance: i32,
}

impl AppService {
    pub(crate) async fn agent_load_memories(
        &self,
        session_id: Uuid,
    ) -> Result<(String, Vec<(Uuid, String, String, i32)>), AppError> {
        let rows: Vec<(Uuid, String, String, i32)> = sqlx::query_as(
            "SELECT id, key, value, importance \
             FROM agent_long_term_memory \
             WHERE session = $1 AND deleted_at IS NULL \
             ORDER BY importance DESC, updated_at DESC \
             LIMIT 50",
        )
        .bind(session_id)
        .fetch_all(self.db.reader())
        .await
        .map_err(|e| AppError::DatabaseError(e.to_string()))?;

        if rows.is_empty() {
            return Ok((String::new(), rows));
        }

        let mut formatted = String::from("Long-term memories for this session:\n");
        for (_, key, value, importance) in &rows {
            formatted.push_str(&format!(
                "- [{}] {} (importance: {})\n",
                key, value, importance
            ));
        }

        Ok((formatted, rows))
    }
    pub(crate) async fn agent_persist_memories(
        &self,
        session_id: Uuid,
        memories: &[PendingMemory],
    ) -> Result<(), AppError> {
        if memories.is_empty() {
            return Ok(());
        }

        let now = Utc::now();
        for mem in memories {
            sqlx::query(
                "INSERT INTO agent_long_term_memory \
                 (id, session, key, value, importance, created_at, updated_at) \
                 VALUES ($1, $2, $3, $4, $5, $6, $6) \
                 ON CONFLICT (session, key) WHERE deleted_at IS NULL \
                 DO UPDATE SET value = $4, importance = $5, updated_at = $6",
            )
            .bind(Uuid::now_v7())
            .bind(session_id)
            .bind(&mem.key)
            .bind(&mem.value)
            .bind(mem.importance)
            .bind(now)
            .execute(self.db.writer())
            .await
            .map_err(|e| AppError::DatabaseError(e.to_string()))?;
        }

        info!(
            session_id = %session_id,
            count = memories.len(),
            "persisted long-term memories from agent run"
        );

        Ok(())
    }
    #[allow(dead_code)]
    pub(crate) async fn agent_touch_memories(
        &self,
        memory_ids: &[Uuid],
    ) -> Result<(), AppError> {
        if memory_ids.is_empty() {
            return Ok(());
        }

        let now = Utc::now();
        sqlx::query(
            "UPDATE agent_long_term_memory \
             SET last_used_at = $1 \
             WHERE id = ANY($2::uuid[])",
        )
        .bind(now)
        .bind(memory_ids)
        .execute(self.db.writer())
        .await
        .map_err(|e| AppError::DatabaseError(e.to_string()))?;

        Ok(())
    }
}