//! The `repositories` and `pushes` tables.

use super::{now_ms, Pool};
use hub_api::Visibility;
use sqlx::FromRow;

#[derive(Clone, Debug, Default, FromRow)]
pub struct RepoRow {
    pub id: i64,
    pub owner: String,
    pub name: String,
    pub description: String,
    pub default_bookmark: String,
    pub visibility: String,
    pub created_ms: i64,
    pub updated_ms: i64,
    #[sqlx(default)]
    pub git_mirror: bool,
    #[sqlx(default)]
    pub git_mirror_state: String,
    /// The repository this one was forked from (migration 0009).
    #[sqlx(default)]
    pub forked_from: Option<i64>,
    /// Space-separated topics (migration 0010).
    #[sqlx(default)]
    pub topics: String,
    /// OxygenFlow: `on`, `off`, or empty to follow hub.toml (migration 0018).
    #[sqlx(default)]
    pub flow: String,
    /// Diffusion: `off`, `green`, `any`, or empty to follow hub.toml
    /// (migration 0058, #148).
    #[sqlx(default)]
    pub diffusion: String,
    /// Read-only, with why (migration 0040, #108).
    #[sqlx(default)]
    pub archived: bool,
    #[sqlx(default)]
    pub archived_reason: String,
    /// Counts for the tabs; filled by `get` only.
    #[sqlx(default)]
    pub open_issues: i64,
    #[sqlx(default)]
    pub open_proposals: i64,
}

impl RepoRow {
    pub fn visibility(&self) -> Visibility {
        Visibility::parse(&self.visibility).unwrap_or(Visibility::Private)
    }

    pub fn topic_list(&self) -> Vec<&str> {
        self.topics.split_whitespace().collect()
    }

    pub fn slug(&self) -> String {
        format!("{}/{}", self.owner, self.name)
    }
}

#[derive(Clone, Debug, FromRow)]
pub struct PushRow {
    pub id: i64,
    pub at_ms: i64,
    pub reference: String,
    pub ok: bool,
    pub reason: String,
    pub old_state: String,
    pub new_state: String,
    pub heads: i64,
    pub changes: i64,
    pub pusher: String,
}

/// One reference's outcome in a push, as the protocol backend reports it.
#[derive(Clone, Debug)]
pub struct PushOutcome {
    pub reference: String,
    pub ok: bool,
    pub reason: String,
    pub old_state: String,
    pub new_state: String,
    pub heads: i64,
    pub changes: i64,
}

pub async fn list(pool: &Pool) -> sqlx::Result<Vec<RepoRow>> {
    sqlx::query_as("SELECT * FROM repositories ORDER BY updated_ms DESC, owner, name").fetch_all(pool).await
}

pub async fn get_by_id(pool: &Pool, id: i64) -> sqlx::Result<Option<RepoRow>> {
    sqlx::query_as("SELECT * FROM repositories WHERE id = ?").bind(id).fetch_optional(pool).await
}

pub async fn list_by_owner(pool: &Pool, owner: &str) -> sqlx::Result<Vec<RepoRow>> {
    sqlx::query_as("SELECT * FROM repositories WHERE owner = ? ORDER BY updated_ms DESC, name").bind(owner).fetch_all(pool).await
}

/// One repository, with its open issue and proposal counts for the tabs.
pub async fn get(pool: &Pool, owner: &str, name: &str) -> sqlx::Result<Option<RepoRow>> {
    sqlx::query_as(
        "SELECT r.*, \
           (SELECT COUNT(*) FROM issues i WHERE i.repo_id = r.id AND i.state = 'open') AS open_issues, \
           (SELECT COUNT(*) FROM proposals p WHERE p.repo_id = r.id AND p.state IN ('open', 'draft')) AS open_proposals \
         FROM repositories r WHERE r.owner = ? AND r.name = ?",
    )
    .bind(owner)
    .bind(name)
    .fetch_optional(pool)
    .await
}

/// Create a repository row. One under an organisation of two or more
/// members requires one sealed approval to land a proposal (oxygenhub#64),
/// since someone other than the author can then give it; others require none.
pub async fn create(pool: &Pool, owner: &str, name: &str, description: &str, visibility: Visibility) -> sqlx::Result<RepoRow> {
    let now = now_ms();
    sqlx::query_as(
        "INSERT INTO repositories (owner, name, description, visibility, created_ms, updated_ms, required_approvals) \
         VALUES (?, ?, ?, ?, ?, ?, (SELECT COUNT(*) >= 2 FROM org_members m JOIN organisations o ON o.id = m.org_id WHERE o.name = ?)) RETURNING *",
    )
    .bind(owner)
    .bind(name)
    .bind(description)
    .bind(visibility.as_str())
    .bind(now)
    .bind(now)
    .bind(owner)
    .fetch_one(pool)
    .await
}

/// The repository an old name now points at, after a transfer.
pub async fn moved_to(pool: &Pool, owner: &str, name: &str) -> sqlx::Result<Option<RepoRow>> {
    let id: Option<i64> = sqlx::query_scalar("SELECT repo_id FROM repo_redirects WHERE old_owner = ? AND old_name = ?")
        .bind(owner)
        .bind(name)
        .fetch_optional(pool)
        .await?;
    match id {
        Some(id) => get_by_id(pool, id).await,
        None => Ok(None),
    }
}

/// Move a repository to another owner, keeping its name: the row, and a
/// redirect from the old name. A redirect that pointed at the new name
/// goes, so names never loop.
pub async fn transfer(pool: &Pool, id: i64, old_owner: &str, name: &str, new_owner: &str) -> sqlx::Result<()> {
    sqlx::query("UPDATE repositories SET owner = ?, updated_ms = ? WHERE id = ?")
        .bind(new_owner)
        .bind(now_ms())
        .bind(id)
        .execute(pool)
        .await?;
    sqlx::query("DELETE FROM repo_redirects WHERE old_owner = ? AND old_name = ?").bind(new_owner).bind(name).execute(pool).await?;
    sqlx::query("INSERT OR REPLACE INTO repo_redirects (old_owner, old_name, repo_id, moved_ms) VALUES (?, ?, ?, ?)")
        .bind(old_owner)
        .bind(name)
        .bind(id)
        .bind(now_ms())
        .execute(pool)
        .await?;
    Ok(())
}

/// Archive (read-only) or bring back a repository.
pub async fn set_archived(pool: &Pool, id: i64, archived: bool, reason: &str) -> sqlx::Result<()> {
    sqlx::query("UPDATE repositories SET archived = ?, archived_reason = ?, updated_ms = ? WHERE id = ?")
        .bind(archived)
        .bind(if archived { reason } else { "" })
        .bind(now_ms())
        .bind(id)
        .execute(pool)
        .await?;
    Ok(())
}

pub async fn delete(pool: &Pool, id: i64) -> sqlx::Result<()> {
    sqlx::query("DELETE FROM repositories WHERE id = ?").bind(id).execute(pool).await?;
    Ok(())
}

pub async fn set_description(pool: &Pool, id: i64, description: &str) -> sqlx::Result<()> {
    sqlx::query("UPDATE repositories SET description = ? WHERE id = ?").bind(description).bind(id).execute(pool).await?;
    Ok(())
}

pub async fn set_default_bookmark(pool: &Pool, id: i64, bookmark: &str) -> sqlx::Result<()> {
    sqlx::query("UPDATE repositories SET default_bookmark = ? WHERE id = ?").bind(bookmark).bind(id).execute(pool).await?;
    Ok(())
}

pub async fn set_visibility(pool: &Pool, id: i64, visibility: Visibility) -> sqlx::Result<()> {
    sqlx::query("UPDATE repositories SET visibility = ? WHERE id = ?").bind(visibility.as_str()).bind(id).execute(pool).await?;
    Ok(())
}

/// Record a push's per-reference results and bump the repository's activity.
pub async fn record_push(pool: &Pool, id: i64, pusher: Option<(i64, &str)>, results: &[PushOutcome]) -> sqlx::Result<()> {
    let now = now_ms();
    let mut tx = super::begin_write(pool).await?;
    for r in results {
        sqlx::query("INSERT INTO pushes (repo_id, at_ms, reference, ok, reason, old_state, new_state, heads, changes, account_id, pusher) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)")
            .bind(id)
            .bind(now)
            .bind(&r.reference)
            .bind(r.ok)
            .bind(&r.reason)
            .bind(&r.old_state)
            .bind(&r.new_state)
            .bind(r.heads)
            .bind(r.changes)
            .bind(pusher.map(|p| p.0).filter(|id| *id > 0))
            .bind(pusher.map(|p| p.1).unwrap_or(""))
            .execute(&mut *tx)
            .await?;
    }
    if results.iter().any(|r| r.ok) {
        sqlx::query("UPDATE repositories SET updated_ms = ? WHERE id = ?").bind(now).bind(id).execute(&mut *tx).await?;
    }
    tx.commit().await
}

pub async fn pushes(pool: &Pool, id: i64, limit: i64) -> sqlx::Result<Vec<PushRow>> {
    sqlx::query_as("SELECT id, at_ms, reference, ok, reason, old_state, new_state, heads, changes, pusher FROM pushes WHERE repo_id = ? ORDER BY at_ms DESC, id DESC LIMIT ?")
        .bind(id)
        .bind(limit)
        .fetch_all(pool)
        .await
}

/// Topics from user input: comma or space separated, lower-cased,
/// letters, digits and dashes, at most 35 characters each and 20 in all.
/// Returns the stored form or what is wrong.
pub fn parse_topics(input: &str) -> Result<String, String> {
    let mut out: Vec<String> = Vec::new();
    for t in input.split([',', ' ', '\n', '\t']).map(|t| t.trim().to_ascii_lowercase()).filter(|t| !t.is_empty()) {
        if t.len() > 35 || !t.chars().all(|c| c.is_ascii_alphanumeric() || c == '-') || t.starts_with('-') {
            return Err(format!("\"{t}\" is not a topic: use letters, digits and dashes, up to 35 characters"));
        }
        if !out.contains(&t) {
            out.push(t);
        }
    }
    if out.len() > 20 {
        return Err("At most 20 topics.".into());
    }
    Ok(out.join(" "))
}

pub async fn set_topics(pool: &Pool, id: i64, topics: &str) -> sqlx::Result<()> {
    sqlx::query("UPDATE repositories SET topics = ? WHERE id = ?").bind(topics).bind(id).execute(pool).await?;
    Ok(())
}

/// Star or unstar; returns whether it is now starred.
pub async fn toggle_star(pool: &Pool, account_id: i64, repo_id: i64) -> sqlx::Result<bool> {
    let gone = sqlx::query("DELETE FROM stars WHERE account_id = ? AND repo_id = ?").bind(account_id).bind(repo_id).execute(pool).await?;
    if gone.rows_affected() > 0 {
        return Ok(false);
    }
    sqlx::query("INSERT INTO stars (account_id, repo_id, at_ms) VALUES (?, ?, ?)")
        .bind(account_id)
        .bind(repo_id)
        .bind(now_ms())
        .execute(pool)
        .await?;
    Ok(true)
}

pub async fn starred(pool: &Pool, account_id: i64, repo_id: i64) -> sqlx::Result<bool> {
    let n: i64 = sqlx::query_scalar("SELECT COUNT(*) FROM stars WHERE account_id = ? AND repo_id = ?")
        .bind(account_id)
        .bind(repo_id)
        .fetch_one(pool)
        .await?;
    Ok(n > 0)
}

/// Stars and watchers of one repository.
pub async fn counts(pool: &Pool, repo_id: i64) -> sqlx::Result<(i64, i64)> {
    let stars: i64 = sqlx::query_scalar("SELECT COUNT(*) FROM stars WHERE repo_id = ?").bind(repo_id).fetch_one(pool).await?;
    let watchers: i64 = sqlx::query_scalar("SELECT COUNT(*) FROM watches WHERE repo_id = ?").bind(repo_id).fetch_one(pool).await?;
    Ok((stars, watchers))
}

/// Star counts of every starred repository.
pub async fn star_counts(pool: &Pool) -> sqlx::Result<std::collections::HashMap<i64, i64>> {
    let rows: Vec<(i64, i64)> = sqlx::query_as("SELECT repo_id, COUNT(*) FROM stars GROUP BY repo_id").fetch_all(pool).await?;
    Ok(rows.into_iter().collect())
}

/// Record that `id` is a fork of `from`.
pub async fn set_forked_from(pool: &Pool, id: i64, from: i64) -> sqlx::Result<()> {
    sqlx::query("UPDATE repositories SET forked_from = ? WHERE id = ?").bind(from).bind(id).execute(pool).await?;
    Ok(())
}

/// The forks of `id`, newest activity first.
pub async fn forks_of(pool: &Pool, id: i64) -> sqlx::Result<Vec<RepoRow>> {
    sqlx::query_as("SELECT * FROM repositories WHERE forked_from = ? ORDER BY updated_ms DESC").bind(id).fetch_all(pool).await
}

/// `on`, `off`, or `` (follow hub.toml's `[flow] repos`).
pub async fn set_flow(pool: &Pool, id: i64, setting: &str) -> sqlx::Result<()> {
    sqlx::query("UPDATE repositories SET flow = ? WHERE id = ?").bind(setting).bind(id).execute(pool).await?;
    Ok(())
}

pub async fn set_diffusion(pool: &Pool, id: i64, setting: &str) -> sqlx::Result<()> {
    sqlx::query("UPDATE repositories SET diffusion = ? WHERE id = ?").bind(setting).bind(id).execute(pool).await?;
    Ok(())
}

pub async fn set_git_mirror(pool: &Pool, id: i64, on: bool) -> sqlx::Result<()> {
    sqlx::query("UPDATE repositories SET git_mirror = ? WHERE id = ?").bind(on).bind(id).execute(pool).await?;
    Ok(())
}

pub async fn set_git_mirror_state(pool: &Pool, id: i64, state: &str) -> sqlx::Result<()> {
    sqlx::query("UPDATE repositories SET git_mirror_state = ? WHERE id = ?").bind(state).bind(id).execute(pool).await?;
    Ok(())
}

#[cfg(test)]
mod topic_tests {
    use super::parse_topics;

    #[test]
    fn topics_are_normalised_and_checked() {
        assert_eq!(parse_topics("Rust, vcs  retro-computing,rust").unwrap(), "rust vcs retro-computing");
        assert_eq!(parse_topics("").unwrap(), "");
        assert!(parse_topics("c++").is_err());
        assert!(parse_topics("-lead").is_err());
        assert!(parse_topics(&"x".repeat(36)).is_err());
        assert!(parse_topics(&(0..21).map(|i| format!("t{i}")).collect::<Vec<_>>().join(" ")).is_err());
    }
}