#![allow(dead_code)]

use diesel::prelude::*;
use diesel::sqlite::SqliteConnection;
use std::ops::DerefMut;
use std::sync::{Arc, Mutex};

use crate::database::models::{InsertPersona, Persona};
use crate::database::schema;
use crate::database::{DbError, DbErrorKind, connect};
use crate::otel::trace_db_call;

/// One row of the persona-chat transcript. Lives in
/// `persona_chat_conversations` (one row per `(user_id, persona_id)`).
///
/// One persona conversation.
///
/// `turn_count` is the cumulative number of assistant turns on the active
/// branch — what the list screen shows as the length of a conversation. The
/// transcript itself is the `messages_json` blob, holding a serialized
/// `ChatHistoryStore` tree. `title` is a generated summary of the opening
/// exchange, empty until the first turn completes.
#[derive(Clone, Debug)]
pub struct PersonaChatRow {
    pub conversation_id: String,
    pub persona_id: String,
    pub title: String,
    pub messages_json: String,
    pub turn_count: i32,
    pub created_at: i64,
    pub updated_at: i64,
    /// The SMS thread position this conversation grew out of, for chats
    /// started via "Continue with persona". None for an open chat.
    pub anchor: Option<SmsAnchor>,
}

/// Where in an SMS thread an anchored persona conversation picks up.
///
/// `contact_id` / `message_id` are SMS-API ids. `context` is the rendered
/// snapshot of the thread leading up to the anchor, captured once at
/// creation and spliced into the system prompt on every turn.
#[derive(Clone, Debug, PartialEq)]
pub struct SmsAnchor {
    pub contact_id: i64,
    pub contact_name: String,
    pub message_id: i64,
    /// Unix seconds of the anchor message.
    pub timestamp: i64,
    pub context: String,
}

/// The column tuple every persona-chat read selects. Shared by the
/// single-row and list queries so their `select(...)` orders can never
/// drift apart.
type PersonaChatColumns = (
    String,
    String,
    String,
    String,
    i32,
    i64,
    i64,
    Option<i64>,
    Option<String>,
    Option<i64>,
    Option<i64>,
    Option<String>,
);

macro_rules! persona_chat_select {
    () => {
        (
            conversation_id,
            persona_id,
            title,
            messages_json,
            turn_count,
            created_at,
            updated_at,
            anchor_contact_id,
            anchor_contact_name,
            anchor_message_id,
            anchor_ts,
            anchor_context,
        )
    };
}

/// Column tuple → `PersonaChatRow`.
fn persona_chat_row(
    (
        conversation_id,
        persona_id,
        title,
        messages_json,
        turn_count,
        created_at,
        updated_at,
        anchor_contact_id,
        anchor_contact_name,
        anchor_message_id,
        anchor_ts,
        anchor_context,
    ): PersonaChatColumns,
) -> PersonaChatRow {
    // An anchor needs at least the thread and the message; the rest has a
    // usable default if a row was written half-way by hand.
    let anchor = match (anchor_contact_id, anchor_message_id) {
        (Some(contact_id), Some(message_id)) => Some(SmsAnchor {
            contact_id,
            contact_name: anchor_contact_name.unwrap_or_default(),
            message_id,
            timestamp: anchor_ts.unwrap_or(0),
            context: anchor_context.unwrap_or_default(),
        }),
        _ => None,
    };
    PersonaChatRow {
        conversation_id,
        persona_id,
        title,
        messages_json,
        turn_count,
        created_at,
        updated_at,
        anchor,
    }
}

/// Patch shape for update_persona. None = leave field alone. Built-ins are
/// allowed to flip `include_all_memories` but should reject name/prompt
/// edits at the handler layer (built-in copy lives in the migration).
pub struct PersonaPatch {
    pub name: Option<String>,
    pub system_prompt: Option<String>,
    pub include_all_memories: Option<bool>,
    pub reviewed_only_facts: Option<bool>,
    pub allow_agent_corrections: Option<bool>,
}

/// One row of a bulk migration upload. Fields named to match the JSON
/// shape the mobile client uploads (`POST /personas/migrate`).
pub struct ImportPersona {
    pub persona_id: String,
    pub name: String,
    pub system_prompt: String,
    pub is_built_in: bool,
    pub created_at: i64,
}

pub trait PersonaDao: Sync + Send {
    fn list_personas(&mut self, user_id: i32) -> Result<Vec<Persona>, DbError>;

    fn get_persona(&mut self, user_id: i32, persona_id: &str) -> Result<Option<Persona>, DbError>;

    fn create_persona(
        &mut self,
        user_id: i32,
        persona_id: &str,
        name: &str,
        system_prompt: &str,
        is_built_in: bool,
        include_all_memories: bool,
    ) -> Result<Persona, DbError>;

    fn update_persona(
        &mut self,
        user_id: i32,
        persona_id: &str,
        patch: PersonaPatch,
    ) -> Result<Option<Persona>, DbError>;

    fn delete_persona(&mut self, user_id: i32, persona_id: &str) -> Result<bool, DbError>;

    /// Idempotent bulk import. INSERT OR IGNORE on (user_id, persona_id)
    /// — re-uploading the same set is a no-op. Returns the number of rows
    /// actually inserted (skipped duplicates don't count).
    fn bulk_import(&mut self, user_id: i32, personas: &[ImportPersona]) -> Result<usize, DbError>;

    // ── Persona-chat (open chat with persona) persistence ───────────
    //
    // Keyed on an opaque `conversation_id` so one persona can hold several
    // separate conversations. `user_id` is checked on every read and write:
    // the id is a bearer token for a transcript, so ownership can never be
    // assumed from the id alone.

    /// Fetch one conversation. None when it doesn't exist or belongs to
    /// another user — the two are deliberately indistinguishable to callers.
    fn get_persona_chat(
        &mut self,
        user_id: i32,
        conversation_id: &str,
    ) -> Result<Option<PersonaChatRow>, DbError>;

    /// Every conversation this user has going, newest first. Backs the chat
    /// list screen, so it returns the transcript blob too — the snippet is
    /// derived from the tree rather than denormalized into its own column.
    fn list_persona_chats(&mut self, user_id: i32) -> Result<Vec<PersonaChatRow>, DbError>;

    /// Start a new conversation with a persona, returning its id. Several
    /// conversations with the same persona are expected, so this never
    /// reuses an existing row.
    fn create_persona_chat(
        &mut self,
        user_id: i32,
        persona_id: &str,
        created_at: i64,
    ) -> Result<String, DbError>;

    /// Start a new conversation anchored on a point in an SMS thread
    /// ("Continue with persona"). Same as `create_persona_chat` plus the
    /// anchor columns.
    fn create_anchored_persona_chat(
        &mut self,
        user_id: i32,
        persona_id: &str,
        created_at: i64,
        anchor: &SmsAnchor,
    ) -> Result<String, DbError>;

    /// Replace a conversation's transcript. Called once per completed turn
    /// with the full new `messages_json`; `turn_count` is the cumulative
    /// assistant-turn count on the resulting active branch. Returns the
    /// number of rows written — 0 means the conversation is gone or is not
    /// this user's.
    fn update_persona_chat(
        &mut self,
        user_id: i32,
        conversation_id: &str,
        messages_json: &str,
        turn_count: i32,
        updated_at: i64,
    ) -> Result<usize, DbError>;

    /// Name a conversation. Written once, after the first turn produces
    /// enough of an exchange to summarize.
    fn set_persona_chat_title(
        &mut self,
        user_id: i32,
        conversation_id: &str,
        title: &str,
    ) -> Result<(), DbError>;

    /// Delete a conversation outright. Backs both the list screen's delete
    /// affordance and the reset endpoint.
    fn delete_persona_chat(&mut self, user_id: i32, conversation_id: &str) -> Result<(), DbError>;
}

pub struct SqlitePersonaDao {
    connection: Arc<Mutex<SqliteConnection>>,
}

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

impl SqlitePersonaDao {
    pub fn new() -> Self {
        Self {
            connection: Arc::new(Mutex::new(connect())),
        }
    }

    pub fn from_connection(conn: Arc<Mutex<SqliteConnection>>) -> Self {
        Self { connection: conn }
    }
}

impl PersonaDao for SqlitePersonaDao {
    fn list_personas(&mut self, uid: i32) -> Result<Vec<Persona>, DbError> {
        trace_db_call("query", "list_personas", |_span| {
            use schema::personas::dsl::*;
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            personas
                .filter(user_id.eq(uid))
                .order(created_at.asc())
                .load::<Persona>(conn.deref_mut())
                .map_err(|e| anyhow::anyhow!("Query error: {}", e))
        })
        .map_err(|e| DbError::log(DbErrorKind::QueryError, e))
    }

    fn get_persona(&mut self, uid: i32, pid: &str) -> Result<Option<Persona>, DbError> {
        trace_db_call("query", "get_persona", |_span| {
            use schema::personas::dsl::*;
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            personas
                .filter(user_id.eq(uid))
                .filter(persona_id.eq(pid))
                .first::<Persona>(conn.deref_mut())
                .optional()
                .map_err(|e| anyhow::anyhow!("Query error: {}", e))
        })
        .map_err(|e| DbError::log(DbErrorKind::QueryError, e))
    }

    fn create_persona(
        &mut self,
        uid: i32,
        pid: &str,
        nm: &str,
        prompt: &str,
        builtin: bool,
        include_all: bool,
    ) -> Result<Persona, DbError> {
        trace_db_call("insert", "create_persona", |_span| {
            use schema::personas::dsl::*;
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            let now = chrono::Utc::now().timestamp_millis();

            diesel::insert_into(personas)
                .values(InsertPersona {
                    user_id: uid,
                    persona_id: pid,
                    name: nm,
                    system_prompt: prompt,
                    is_built_in: builtin,
                    include_all_memories: include_all,
                    created_at: now,
                    updated_at: now,
                    reviewed_only_facts: false,
                    allow_agent_corrections: false,
                })
                .execute(conn.deref_mut())
                .map_err(|e| anyhow::anyhow!("Insert error: {}", e))?;

            personas
                .filter(user_id.eq(uid))
                .filter(persona_id.eq(pid))
                .first::<Persona>(conn.deref_mut())
                .map_err(|e| anyhow::anyhow!("Query error: {}", e))
        })
        .map_err(|e| DbError::log(DbErrorKind::InsertError, e))
    }

    fn update_persona(
        &mut self,
        uid: i32,
        pid: &str,
        patch: PersonaPatch,
    ) -> Result<Option<Persona>, DbError> {
        trace_db_call("update", "update_persona", |_span| {
            use schema::personas::dsl::*;
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            let now = chrono::Utc::now().timestamp_millis();

            // Apply each field as its own UPDATE — keeps types simple
            // (Diesel's tuple updates don't compose cleanly across optional
            // columns) and matches the pattern already in use for entities
            // (knowledge_dao.rs::update_entity).
            if let Some(ref new_name) = patch.name {
                diesel::update(personas.filter(user_id.eq(uid)).filter(persona_id.eq(pid)))
                    .set((name.eq(new_name), updated_at.eq(now)))
                    .execute(conn.deref_mut())
                    .map_err(|e| anyhow::anyhow!("Update name error: {}", e))?;
            }
            if let Some(ref new_prompt) = patch.system_prompt {
                diesel::update(personas.filter(user_id.eq(uid)).filter(persona_id.eq(pid)))
                    .set((system_prompt.eq(new_prompt), updated_at.eq(now)))
                    .execute(conn.deref_mut())
                    .map_err(|e| anyhow::anyhow!("Update prompt error: {}", e))?;
            }
            if let Some(new_include_all) = patch.include_all_memories {
                diesel::update(personas.filter(user_id.eq(uid)).filter(persona_id.eq(pid)))
                    .set((include_all_memories.eq(new_include_all), updated_at.eq(now)))
                    .execute(conn.deref_mut())
                    .map_err(|e| anyhow::anyhow!("Update include_all error: {}", e))?;
            }
            if let Some(new_reviewed_only) = patch.reviewed_only_facts {
                diesel::update(personas.filter(user_id.eq(uid)).filter(persona_id.eq(pid)))
                    .set((
                        reviewed_only_facts.eq(new_reviewed_only),
                        updated_at.eq(now),
                    ))
                    .execute(conn.deref_mut())
                    .map_err(|e| anyhow::anyhow!("Update reviewed_only_facts error: {}", e))?;
            }
            if let Some(new_allow_corrections) = patch.allow_agent_corrections {
                diesel::update(personas.filter(user_id.eq(uid)).filter(persona_id.eq(pid)))
                    .set((
                        allow_agent_corrections.eq(new_allow_corrections),
                        updated_at.eq(now),
                    ))
                    .execute(conn.deref_mut())
                    .map_err(|e| anyhow::anyhow!("Update allow_agent_corrections error: {}", e))?;
            }

            personas
                .filter(user_id.eq(uid))
                .filter(persona_id.eq(pid))
                .first::<Persona>(conn.deref_mut())
                .optional()
                .map_err(|e| anyhow::anyhow!("Query error: {}", e))
        })
        .map_err(|e| DbError::log(DbErrorKind::UpdateError, e))
    }

    fn delete_persona(&mut self, uid: i32, pid: &str) -> Result<bool, DbError> {
        trace_db_call("delete", "delete_persona", |_span| {
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            // One transaction so a persona and its conversations can't get
            // out of step. There is no FK between the two tables, and the
            // chat list skips conversations whose persona is gone — so
            // without this the transcripts would linger invisibly forever.
            conn.deref_mut().transaction::<_, anyhow::Error, _>(|tx| {
                {
                    use schema::persona_chat_conversations::dsl::*;
                    diesel::delete(
                        persona_chat_conversations
                            .filter(user_id.eq(uid))
                            .filter(persona_id.eq(pid)),
                    )
                    .execute(tx)
                    .map_err(|e| anyhow::anyhow!("Delete error: {}", e))?;
                }
                use schema::personas::dsl::*;
                let n = diesel::delete(personas.filter(user_id.eq(uid)).filter(persona_id.eq(pid)))
                    .execute(tx)
                    .map_err(|e| anyhow::anyhow!("Delete error: {}", e))?;
                Ok(n > 0)
            })
        })
        .map_err(|e| DbError::log(DbErrorKind::QueryError, e))
    }

    fn bulk_import(&mut self, uid: i32, rows: &[ImportPersona]) -> Result<usize, DbError> {
        trace_db_call("insert", "bulk_import_personas", |_span| {
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            let now = chrono::Utc::now().timestamp_millis();
            let mut inserted = 0usize;

            // INSERT OR IGNORE on the (user_id, persona_id) UNIQUE so
            // re-running migrate is a no-op for personas already on the
            // server.
            for p in rows {
                let n = diesel::sql_query(
                    "INSERT OR IGNORE INTO personas (user_id, persona_id, name, system_prompt, \
                     is_built_in, include_all_memories, created_at, updated_at) \
                     VALUES (?, ?, ?, ?, ?, 0, ?, ?)",
                )
                .bind::<diesel::sql_types::Integer, _>(uid)
                .bind::<diesel::sql_types::Text, _>(&p.persona_id)
                .bind::<diesel::sql_types::Text, _>(&p.name)
                .bind::<diesel::sql_types::Text, _>(&p.system_prompt)
                .bind::<diesel::sql_types::Bool, _>(p.is_built_in)
                .bind::<diesel::sql_types::BigInt, _>(p.created_at)
                .bind::<diesel::sql_types::BigInt, _>(now)
                .execute(conn.deref_mut())
                .map_err(|e| anyhow::anyhow!("Insert error: {}", e))?;
                inserted += n;
            }
            Ok(inserted)
        })
        .map_err(|e| DbError::log(DbErrorKind::InsertError, e))
    }

    fn get_persona_chat(&mut self, uid: i32, cid: &str) -> Result<Option<PersonaChatRow>, DbError> {
        trace_db_call("query", "get_persona_chat", |_span| {
            use schema::persona_chat_conversations::dsl::*;
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            persona_chat_conversations
                .filter(conversation_id.eq(cid))
                // Scoped by user as well as id: the id is a bearer token for
                // someone's transcript, so it never grants access on its own.
                .filter(user_id.eq(uid))
                .select(persona_chat_select!())
                .first::<PersonaChatColumns>(conn.deref_mut())
                .optional()
                .map(|opt| opt.map(persona_chat_row))
                .map_err(|e| anyhow::anyhow!("Query error: {}", e))
        })
        .map_err(|e| DbError::log(DbErrorKind::QueryError, e))
    }

    fn list_persona_chats(&mut self, uid: i32) -> Result<Vec<PersonaChatRow>, DbError> {
        trace_db_call("query", "list_persona_chats", |_span| {
            use schema::persona_chat_conversations::dsl::*;
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            persona_chat_conversations
                .filter(user_id.eq(uid))
                .order(updated_at.desc())
                .select(persona_chat_select!())
                .load::<PersonaChatColumns>(conn.deref_mut())
                .map(|rows| rows.into_iter().map(persona_chat_row).collect())
                .map_err(|e| anyhow::anyhow!("Query error: {}", e))
        })
        .map_err(|e| DbError::log(DbErrorKind::QueryError, e))
    }

    fn create_persona_chat(
        &mut self,
        uid: i32,
        pid: &str,
        created: i64,
    ) -> Result<String, DbError> {
        trace_db_call("insert", "create_persona_chat", |_span| {
            use schema::persona_chat_conversations::dsl::*;
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            let new_id = uuid::Uuid::new_v4().to_string();
            diesel::insert_into(persona_chat_conversations)
                .values((
                    conversation_id.eq(&new_id),
                    user_id.eq(uid),
                    persona_id.eq(pid),
                    title.eq(""),
                    // The empty tree; the first turn seeds it with the
                    // persona's system prompt.
                    messages_json.eq("[]"),
                    turn_count.eq(0),
                    created_at.eq(created),
                    updated_at.eq(created),
                ))
                .execute(conn.deref_mut())
                .map_err(|e| anyhow::anyhow!("Insert error: {}", e))?;
            Ok(new_id)
        })
        .map_err(|e| DbError::log(DbErrorKind::InsertError, e))
    }

    fn create_anchored_persona_chat(
        &mut self,
        uid: i32,
        pid: &str,
        created: i64,
        anchor: &SmsAnchor,
    ) -> Result<String, DbError> {
        trace_db_call("insert", "create_anchored_persona_chat", |_span| {
            use schema::persona_chat_conversations::dsl::*;
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            let new_id = uuid::Uuid::new_v4().to_string();
            diesel::insert_into(persona_chat_conversations)
                .values((
                    conversation_id.eq(&new_id),
                    user_id.eq(uid),
                    persona_id.eq(pid),
                    title.eq(""),
                    messages_json.eq("[]"),
                    turn_count.eq(0),
                    created_at.eq(created),
                    updated_at.eq(created),
                    anchor_contact_id.eq(Some(anchor.contact_id)),
                    anchor_contact_name.eq(Some(&anchor.contact_name)),
                    anchor_message_id.eq(Some(anchor.message_id)),
                    anchor_ts.eq(Some(anchor.timestamp)),
                    anchor_context.eq(Some(&anchor.context)),
                ))
                .execute(conn.deref_mut())
                .map_err(|e| anyhow::anyhow!("Insert error: {}", e))?;
            Ok(new_id)
        })
        .map_err(|e| DbError::log(DbErrorKind::InsertError, e))
    }

    fn update_persona_chat(
        &mut self,
        uid: i32,
        cid: &str,
        json: &str,
        count: i32,
        updated: i64,
    ) -> Result<usize, DbError> {
        trace_db_call("update", "update_persona_chat", |_span| {
            use schema::persona_chat_conversations::dsl::*;
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            diesel::update(
                persona_chat_conversations
                    .filter(conversation_id.eq(cid))
                    .filter(user_id.eq(uid)),
            )
            .set((
                messages_json.eq(json),
                turn_count.eq(count),
                updated_at.eq(updated),
            ))
            .execute(conn.deref_mut())
            .map_err(|e| anyhow::anyhow!("Update error: {}", e))
        })
        .map_err(|e| DbError::log(DbErrorKind::QueryError, e))
    }

    fn set_persona_chat_title(
        &mut self,
        uid: i32,
        cid: &str,
        new_title: &str,
    ) -> Result<(), DbError> {
        trace_db_call("update", "set_persona_chat_title", |_span| {
            use schema::persona_chat_conversations::dsl::*;
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            diesel::update(
                persona_chat_conversations
                    .filter(conversation_id.eq(cid))
                    .filter(user_id.eq(uid)),
            )
            .set(title.eq(new_title))
            .execute(conn.deref_mut())
            .map_err(|e| anyhow::anyhow!("Update error: {}", e))?;
            Ok(())
        })
        .map_err(|e| DbError::log(DbErrorKind::QueryError, e))
    }

    fn delete_persona_chat(&mut self, uid: i32, cid: &str) -> Result<(), DbError> {
        trace_db_call("delete", "delete_persona_chat", |_span| {
            use schema::persona_chat_conversations::dsl::*;
            let mut conn = self.connection.lock().expect("PersonaDao lock");
            diesel::delete(
                persona_chat_conversations
                    .filter(conversation_id.eq(cid))
                    .filter(user_id.eq(uid)),
            )
            .execute(conn.deref_mut())
            .map_err(|e| anyhow::anyhow!("Delete error: {}", e))?;
            Ok(())
        })
        .map_err(|e| DbError::log(DbErrorKind::QueryError, e))
    }
}
#[cfg(test)]
mod tests {
    use super::*;
    use crate::database::test::in_memory_db_connection;

    fn dao_with_user(username: &str) -> (SqlitePersonaDao, i32) {
        use crate::database::schema::users::dsl as u;
        let conn = Arc::new(Mutex::new(in_memory_db_connection()));
        diesel::insert_into(u::users)
            .values((u::username.eq(username), u::password.eq("x")))
            .execute(conn.lock().unwrap().deref_mut())
            .unwrap();
        let user_id: i32 = u::users
            .filter(u::username.eq(username))
            .select(u::id)
            .first(conn.lock().unwrap().deref_mut())
            .unwrap();
        (SqlitePersonaDao::from_connection(conn), user_id)
    }

    #[test]
    fn create_and_list_round_trip() {
        let (mut dao, uid) = dao_with_user("alice");

        // The migration seeds 3 built-ins for any existing user; alice
        // was created post-migration so she starts empty.
        let p = dao
            .create_persona(uid, "custom-1", "Custom A", "prompt A", false, false)
            .unwrap();
        assert_eq!(p.persona_id, "custom-1");
        assert_eq!(p.user_id, uid);
        assert!(!p.is_built_in);

        let list = dao.list_personas(uid).unwrap();
        assert_eq!(list.len(), 1);
        assert_eq!(list[0].persona_id, "custom-1");
    }

    #[test]
    fn unique_constraint_blocks_duplicate_persona_id() {
        let (mut dao, uid) = dao_with_user("bob");

        dao.create_persona(uid, "x", "X", "p", false, false)
            .unwrap();
        let err = dao.create_persona(uid, "x", "X2", "p2", false, false);
        assert!(
            err.is_err(),
            "second insert with same persona_id should fail"
        );
    }

    #[test]
    fn bulk_import_is_idempotent() {
        let (mut dao, uid) = dao_with_user("carol");

        let rows = vec![
            ImportPersona {
                persona_id: "custom-a".into(),
                name: "A".into(),
                system_prompt: "p1".into(),
                is_built_in: false,
                created_at: 1,
            },
            ImportPersona {
                persona_id: "custom-b".into(),
                name: "B".into(),
                system_prompt: "p2".into(),
                is_built_in: false,
                created_at: 2,
            },
        ];

        let first = dao.bulk_import(uid, &rows).unwrap();
        assert_eq!(first, 2);
        let second = dao.bulk_import(uid, &rows).unwrap();
        assert_eq!(second, 0, "re-import should insert nothing");

        assert_eq!(dao.list_personas(uid).unwrap().len(), 2);
    }

    #[test]
    fn dao_update_does_not_block_built_ins() {
        // Documenting contract: the DAO is intentionally permissive —
        // `update_persona` will apply name/system_prompt edits to ANY
        // row, including built-ins. The guard against editing built-in
        // identity (name + systemPrompt) lives in the HTTP handler
        // (src/personas.rs::update_persona). If you find yourself
        // wanting to add the guard here too, prefer that — defence in
        // depth — but keep this test passing so anyone who removes
        // the handler guard gets a failing call site, not silent data
        // corruption.
        let (mut dao, uid) = dao_with_user("eve");

        dao.create_persona(uid, "default", "Default", "old", true, false)
            .unwrap();
        let updated = dao
            .update_persona(
                uid,
                "default",
                PersonaPatch {
                    name: Some("Renamed".into()),
                    system_prompt: Some("new prompt".into()),
                    include_all_memories: None,
                    reviewed_only_facts: None,
                    allow_agent_corrections: None,
                },
            )
            .unwrap()
            .unwrap();
        assert_eq!(updated.name, "Renamed");
        assert_eq!(updated.system_prompt, "new prompt");
        assert!(
            updated.is_built_in,
            "is_built_in flag should be unchanged by patch"
        );
    }

    #[test]
    fn update_toggles_include_all_memories() {
        let (mut dao, uid) = dao_with_user("dan");

        dao.create_persona(uid, "j", "Journal", "p", true, false)
            .unwrap();
        let updated = dao
            .update_persona(
                uid,
                "j",
                PersonaPatch {
                    name: None,
                    system_prompt: None,
                    include_all_memories: Some(true),
                    reviewed_only_facts: None,
                    allow_agent_corrections: None,
                },
            )
            .unwrap()
            .unwrap();
        assert!(updated.include_all_memories);
    }

    // ── Persona-chat DAO tests ─────────────────────────────────────

    /// Second user, for the isolation tests.
    fn second_user(dao: &SqlitePersonaDao, username: &str) -> i32 {
        use crate::database::schema::users::dsl as u;
        let conn = dao.connection.clone();
        diesel::insert_into(u::users)
            .values((u::username.eq(username), u::password.eq("x")))
            .execute(conn.lock().unwrap().deref_mut())
            .unwrap();
        u::users
            .filter(u::username.eq(username))
            .select(u::id)
            .first(conn.lock().unwrap().deref_mut())
            .unwrap()
    }

    #[test]
    fn persona_chat_get_returns_none_for_an_unknown_conversation() {
        let (mut dao, uid) = dao_with_user("p1");
        assert!(dao.get_persona_chat(uid, "no-such-id").unwrap().is_none());
    }

    #[test]
    fn persona_chat_create_then_get_round_trip() {
        let (mut dao, uid) = dao_with_user("p2");
        let cid = dao.create_persona_chat(uid, "journal", 100).unwrap();

        let row = dao.get_persona_chat(uid, &cid).unwrap().unwrap();
        assert_eq!(row.conversation_id, cid);
        assert_eq!(row.persona_id, "journal");
        assert_eq!(row.title, "", "unnamed until the first turn completes");
        assert_eq!(row.turn_count, 0);
        assert_eq!(row.created_at, 100);
        assert_eq!(row.updated_at, 100);
    }

    #[test]
    fn persona_chat_create_makes_a_separate_row_each_time() {
        // The whole point of the conversation_id key: one persona, several
        // independent threads.
        let (mut dao, uid) = dao_with_user("p3");
        let first = dao.create_persona_chat(uid, "journal", 100).unwrap();
        let second = dao.create_persona_chat(uid, "journal", 200).unwrap();

        assert_ne!(first, second);
        assert_eq!(dao.list_persona_chats(uid).unwrap().len(), 2);
    }

    #[test]
    fn persona_chat_update_replaces_the_transcript() {
        let (mut dao, uid) = dao_with_user("p4");
        let cid = dao.create_persona_chat(uid, "journal", 100).unwrap();

        let rows = dao.update_persona_chat(uid, &cid, "first", 1, 150).unwrap();
        assert_eq!(rows, 1);
        let rows = dao
            .update_persona_chat(uid, &cid, "second", 2, 200)
            .unwrap();
        assert_eq!(rows, 1);

        let row = dao.get_persona_chat(uid, &cid).unwrap().unwrap();
        assert_eq!(row.messages_json, "second");
        assert_eq!(row.turn_count, 2);
        assert_eq!(row.updated_at, 200);
        assert_eq!(row.created_at, 100, "creation time is not disturbed");
    }

    #[test]
    fn persona_chat_update_reports_zero_rows_for_an_unknown_conversation() {
        // The turn loop treats 0 as "the conversation went away mid-turn"
        // rather than silently succeeding.
        let (mut dao, uid) = dao_with_user("p5");
        let rows = dao
            .update_persona_chat(uid, "no-such-id", "x", 1, 1)
            .unwrap();
        assert_eq!(rows, 0);
    }

    #[test]
    fn persona_chat_set_title_names_the_conversation() {
        let (mut dao, uid) = dao_with_user("p6");
        let cid = dao.create_persona_chat(uid, "journal", 100).unwrap();

        dao.set_persona_chat_title(uid, &cid, "June recap").unwrap();
        let row = dao.get_persona_chat(uid, &cid).unwrap().unwrap();
        assert_eq!(row.title, "June recap");
    }

    #[test]
    fn persona_chat_list_orders_newest_first() {
        let (mut dao, uid) = dao_with_user("p7");
        let older = dao.create_persona_chat(uid, "journal", 100).unwrap();
        let newer = dao.create_persona_chat(uid, "coach", 300).unwrap();
        let middle = dao.create_persona_chat(uid, "default", 200).unwrap();

        let ids: Vec<String> = dao
            .list_persona_chats(uid)
            .unwrap()
            .into_iter()
            .map(|r| r.conversation_id)
            .collect();
        assert_eq!(
            ids,
            vec![newer, middle, older],
            "ordered by updated_at descending so the list screen needs no re-sort"
        );
    }

    #[test]
    fn persona_chat_anchor_round_trips_and_open_chats_have_none() {
        let (mut dao, uid) = dao_with_user("p10");
        let anchor = SmsAnchor {
            contact_id: 42,
            contact_name: "Sam".to_string(),
            message_id: 9001,
            timestamp: 1_700_000_000,
            context: "[2023-11-14 22:13] Sam: see you there".to_string(),
        };
        let anchored = dao
            .create_anchored_persona_chat(uid, "journal", 100, &anchor)
            .unwrap();
        let open = dao.create_persona_chat(uid, "journal", 200).unwrap();

        let row = dao.get_persona_chat(uid, &anchored).unwrap().unwrap();
        assert_eq!(row.anchor, Some(anchor));
        let row = dao.get_persona_chat(uid, &open).unwrap().unwrap();
        assert_eq!(row.anchor, None);
        assert!(
            dao.list_persona_chats(uid)
                .unwrap()
                .iter()
                .any(|r| r.anchor.is_some()),
            "the list query carries the anchor too"
        );
    }

    #[test]
    fn persona_chat_list_is_empty_for_a_user_who_has_never_chatted() {
        let (mut dao, uid) = dao_with_user("p8");
        assert!(dao.list_persona_chats(uid).unwrap().is_empty());
    }

    #[test]
    fn persona_chat_delete_removes_the_conversation() {
        let (mut dao, uid) = dao_with_user("p9");
        let cid = dao.create_persona_chat(uid, "journal", 100).unwrap();

        dao.delete_persona_chat(uid, &cid).unwrap();
        assert!(dao.get_persona_chat(uid, &cid).unwrap().is_none());
        assert!(dao.list_persona_chats(uid).unwrap().is_empty());
    }

    #[test]
    fn deleting_a_persona_takes_its_conversations_with_it() {
        // No FK between the tables, and the chat list hides conversations
        // whose persona is gone — so an orphan row would be an invisible,
        // unreachable transcript sitting in the database forever.
        let (mut dao, uid) = dao_with_user("p-cascade");
        dao.create_persona(uid, "custom-1", "Custom", "prompt", false, false)
            .unwrap();
        dao.create_persona_chat(uid, "custom-1", 100).unwrap();
        dao.create_persona_chat(uid, "custom-1", 200).unwrap();
        let survivor = dao.create_persona_chat(uid, "other", 300).unwrap();

        assert!(dao.delete_persona(uid, "custom-1").unwrap());

        let remaining: Vec<String> = dao
            .list_persona_chats(uid)
            .unwrap()
            .into_iter()
            .map(|r| r.conversation_id)
            .collect();
        assert_eq!(
            remaining,
            vec![survivor],
            "only the untouched persona's conversation survives"
        );
    }

    #[test]
    fn persona_chat_reads_and_writes_are_scoped_to_the_owner() {
        // A conversation_id is a bearer token for someone's transcript, so
        // holding one must not grant another user access to it.
        let (mut dao, uid1) = dao_with_user("owner");
        let uid2 = second_user(&dao, "intruder");
        let cid = dao.create_persona_chat(uid1, "journal", 100).unwrap();
        dao.update_persona_chat(uid1, &cid, "private", 1, 100)
            .unwrap();

        assert!(
            dao.get_persona_chat(uid2, &cid).unwrap().is_none(),
            "another user cannot read it"
        );
        assert_eq!(
            dao.update_persona_chat(uid2, &cid, "tampered", 9, 999)
                .unwrap(),
            0,
            "another user cannot write it"
        );
        dao.delete_persona_chat(uid2, &cid).unwrap();

        let row = dao.get_persona_chat(uid1, &cid).unwrap().unwrap();
        assert_eq!(row.messages_json, "private", "and cannot delete it");
        assert!(dao.list_persona_chats(uid2).unwrap().is_empty());
    }
}