//! Issues, labels, milestones and their events (hub spec §8).

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

#[derive(Clone, Debug, FromRow)]
pub struct IssueRow {
    pub id: i64,
    pub repo_id: i64,
    pub number: i64,
    pub title: String,
    pub body: String,
    pub author_id: Option<i64>,
    pub author: String,
    pub state: String,
    pub reason: String,
    pub locked: bool,
    pub pinned: bool,
    pub milestone_id: Option<i64>,
    pub created_ms: i64,
    pub updated_ms: i64,
    pub closed_ms: Option<i64>,
}

#[derive(Clone, Debug, FromRow)]
pub struct IssueComment {
    pub id: i64,
    pub issue_id: i64,
    pub author_id: Option<i64>,
    pub author: String,
    pub body: String,
    pub created_ms: i64,
    pub edited_ms: Option<i64>,
}

#[derive(Clone, Debug, FromRow)]
pub struct IssueEvent {
    pub id: i64,
    pub at_ms: i64,
    pub actor: String,
    pub event: String,
    pub detail: String,
}

#[derive(Clone, Debug, FromRow, PartialEq, Eq)]
pub struct Label {
    pub id: i64,
    pub repo_id: i64,
    pub name: String,
    pub colour: String,
    pub description: String,
}

#[derive(Clone, Debug, FromRow)]
pub struct Milestone {
    pub id: i64,
    pub repo_id: i64,
    pub title: String,
    pub description: String,
    pub due_ms: Option<i64>,
    pub state: String,
}

pub struct NewIssue<'a> {
    pub repo_id: i64,
    pub title: &'a str,
    pub body: &'a str,
    pub author_id: Option<i64>,
    pub author: &'a str,
}

pub async fn create(pool: &Pool, i: NewIssue<'_>) -> sqlx::Result<IssueRow> {
    let number = super::proposals::next_number(pool, i.repo_id).await?;
    let now = now_ms();
    sqlx::query_as("INSERT INTO issues (repo_id, number, title, body, author_id, author, created_ms, updated_ms) VALUES ($1, $2, $3, $4, $5, $6, $7, $8) RETURNING *")
        .bind(i.repo_id)
        .bind(number)
        .bind(i.title)
        .bind(i.body)
        .bind(i.author_id)
        .bind(i.author)
        .bind(now)
        .bind(now)
        .fetch_one(pool)
        .await
}

pub async fn get(pool: &Pool, repo_id: i64, number: i64) -> sqlx::Result<Option<IssueRow>> {
    sqlx::query_as("SELECT * FROM issues WHERE repo_id = $1 AND number = $2").bind(repo_id).bind(number).fetch_optional(pool).await
}

pub async fn get_by_id(pool: &Pool, id: i64) -> sqlx::Result<Option<IssueRow>> {
    sqlx::query_as("SELECT * FROM issues WHERE id = $1").bind(id).fetch_optional(pool).await
}

pub async fn list(pool: &Pool, repo_id: i64) -> sqlx::Result<Vec<IssueRow>> {
    sqlx::query_as("SELECT * FROM issues WHERE repo_id = $1 ORDER BY pinned DESC, number DESC").bind(repo_id).fetch_all(pool).await
}

/// Numbers in use by issues and proposals, for cross references.
pub async fn numbers(pool: &Pool, repo_id: i64) -> sqlx::Result<(Vec<i64>, Vec<i64>)> {
    let issues: Vec<i64> = sqlx::query_scalar("SELECT number FROM issues WHERE repo_id = $1").bind(repo_id).fetch_all(pool).await?;
    let proposals: Vec<i64> = sqlx::query_scalar("SELECT number FROM proposals WHERE repo_id = $1").bind(repo_id).fetch_all(pool).await?;
    Ok((issues, proposals))
}

pub async fn assigned_to(pool: &Pool, account_id: i64) -> sqlx::Result<Vec<IssueRow>> {
    sqlx::query_as("SELECT i.* FROM issues i JOIN issue_assignees a ON a.issue_id = i.id WHERE a.account_id = $1 AND i.state = 'open' ORDER BY i.updated_ms DESC")
        .bind(account_id)
        .fetch_all(pool)
        .await
}

pub async fn edit(pool: &Pool, id: i64, title: &str, body: &str) -> sqlx::Result<()> {
    sqlx::query("UPDATE issues SET title = $1, body = $2, updated_ms = $3 WHERE id = $4")
        .bind(title)
        .bind(body)
        .bind(now_ms())
        .bind(id)
        .execute(pool)
        .await?;
    Ok(())
}

pub async fn set_state(pool: &Pool, id: i64, state: &str, reason: &str) -> sqlx::Result<()> {
    let now = now_ms();
    let closed: Option<i64> = if state == "closed" { Some(now) } else { None };
    sqlx::query("UPDATE issues SET state = $1, reason = $2, closed_ms = $3, updated_ms = $4 WHERE id = $5")
        .bind(state)
        .bind(reason)
        .bind(closed)
        .bind(now)
        .bind(id)
        .execute(pool)
        .await?;
    Ok(())
}

pub async fn set_flags(pool: &Pool, id: i64, locked: Option<bool>, pinned: Option<bool>) -> sqlx::Result<()> {
    if let Some(l) = locked {
        sqlx::query("UPDATE issues SET locked = $1 WHERE id = $2").bind(l).bind(id).execute(pool).await?;
    }
    if let Some(p) = pinned {
        sqlx::query("UPDATE issues SET pinned = $1 WHERE id = $2").bind(p).bind(id).execute(pool).await?;
    }
    Ok(())
}

pub async fn set_milestone(pool: &Pool, id: i64, milestone_id: Option<i64>) -> sqlx::Result<()> {
    sqlx::query("UPDATE issues SET milestone_id = $1, updated_ms = $2 WHERE id = $3")
        .bind(milestone_id)
        .bind(now_ms())
        .bind(id)
        .execute(pool)
        .await?;
    Ok(())
}

pub async fn touch(pool: &Pool, id: i64) -> sqlx::Result<()> {
    sqlx::query("UPDATE issues SET updated_ms = $1 WHERE id = $2").bind(now_ms()).bind(id).execute(pool).await?;
    Ok(())
}

pub async fn comments(pool: &Pool, issue_id: i64) -> sqlx::Result<Vec<IssueComment>> {
    sqlx::query_as("SELECT * FROM issue_comments WHERE issue_id = $1 ORDER BY created_ms, id").bind(issue_id).fetch_all(pool).await
}

pub async fn add_comment(pool: &Pool, issue_id: i64, author_id: Option<i64>, author: &str, body: &str) -> sqlx::Result<IssueComment> {
    let row = sqlx::query_as(
        "INSERT INTO issue_comments (issue_id, author_id, author, body, created_ms) VALUES ($1, $2, $3, $4, $5) RETURNING *",
    )
    .bind(issue_id)
    .bind(author_id)
    .bind(author)
    .bind(body)
    .bind(now_ms())
    .fetch_one(pool)
    .await?;
    touch(pool, issue_id).await?;
    Ok(row)
}

pub async fn edit_comment(pool: &Pool, id: i64, author_id: i64, body: &str) -> sqlx::Result<bool> {
    let n = sqlx::query("UPDATE issue_comments SET body = $1, edited_ms = $2 WHERE id = $3 AND author_id = $4")
        .bind(body)
        .bind(now_ms())
        .bind(id)
        .bind(author_id)
        .execute(pool)
        .await?;
    Ok(n.rows_affected() > 0)
}

pub async fn delete_comment(pool: &Pool, id: i64) -> sqlx::Result<()> {
    sqlx::query("DELETE FROM issue_comments WHERE id = $1").bind(id).execute(pool).await?;
    Ok(())
}

pub async fn events(pool: &Pool, issue_id: i64) -> sqlx::Result<Vec<IssueEvent>> {
    sqlx::query_as("SELECT id, at_ms, actor, event, detail FROM issue_events WHERE issue_id = $1 ORDER BY at_ms, id")
        .bind(issue_id)
        .fetch_all(pool)
        .await
}

pub async fn add_event(pool: &Pool, issue_id: i64, actor: &str, event: &str, detail: &str) -> sqlx::Result<()> {
    sqlx::query("INSERT INTO issue_events (issue_id, at_ms, actor, event, detail) VALUES ($1, $2, $3, $4, $5)")
        .bind(issue_id)
        .bind(now_ms())
        .bind(actor)
        .bind(event)
        .bind(detail)
        .execute(pool)
        .await?;
    Ok(())
}

// ------------------------------------------------------------------ labels

pub async fn labels(pool: &Pool, repo_id: i64) -> sqlx::Result<Vec<Label>> {
    sqlx::query_as("SELECT * FROM labels WHERE repo_id = $1 ORDER BY name").bind(repo_id).fetch_all(pool).await
}

pub async fn label_by_name(pool: &Pool, repo_id: i64, name: &str) -> sqlx::Result<Option<Label>> {
    sqlx::query_as("SELECT * FROM labels WHERE repo_id = $1 AND name = $2").bind(repo_id).bind(name).fetch_optional(pool).await
}

pub async fn upsert_label(pool: &Pool, repo_id: i64, name: &str, colour: &str, description: &str) -> sqlx::Result<Label> {
    sqlx::query_as("INSERT INTO labels (repo_id, name, colour, description) VALUES ($1, $2, $3, $4) ON CONFLICT (repo_id, name) DO UPDATE SET colour = excluded.colour, description = excluded.description RETURNING *")
        .bind(repo_id)
        .bind(name)
        .bind(colour)
        .bind(description)
        .fetch_one(pool)
        .await
}

pub async fn delete_label(pool: &Pool, id: i64) -> sqlx::Result<()> {
    sqlx::query("DELETE FROM labels WHERE id = $1").bind(id).execute(pool).await?;
    Ok(())
}

pub async fn issue_labels(pool: &Pool, issue_id: i64) -> sqlx::Result<Vec<Label>> {
    sqlx::query_as("SELECT l.* FROM labels l JOIN issue_labels il ON il.label_id = l.id WHERE il.issue_id = $1 ORDER BY l.name")
        .bind(issue_id)
        .fetch_all(pool)
        .await
}

pub async fn set_issue_label(pool: &Pool, issue_id: i64, label_id: i64, on: bool) -> sqlx::Result<()> {
    if on {
        sqlx::query("INSERT OR IGNORE INTO issue_labels (issue_id, label_id) VALUES ($1, $2)")
            .bind(issue_id)
            .bind(label_id)
            .execute(pool)
            .await?;
    } else {
        sqlx::query("DELETE FROM issue_labels WHERE issue_id = $1 AND label_id = $2").bind(issue_id).bind(label_id).execute(pool).await?;
    }
    Ok(())
}

/// Labels of every issue of a repository, for the list page.
/// Every proposal's labels in a repository, for filtering the list.
pub async fn labels_by_proposal(pool: &Pool, repo_id: i64) -> sqlx::Result<Vec<(i64, Label)>> {
    let rows: Vec<(i64, i64, i64, String, String, String)> = sqlx::query_as(
        "SELECT pl.proposal_id, l.id, l.repo_id, l.name, l.colour, l.description FROM proposal_labels pl JOIN labels l ON l.id = pl.label_id JOIN proposals p ON p.id = pl.proposal_id WHERE p.repo_id = $1 ORDER BY l.name",
    )
    .bind(repo_id)
    .fetch_all(pool)
    .await?;
    Ok(rows
        .into_iter()
        .map(|(proposal_id, id, repo_id, name, colour, description)| (proposal_id, Label { id, repo_id, name, colour, description }))
        .collect())
}

pub async fn labels_by_issue(pool: &Pool, repo_id: i64) -> sqlx::Result<Vec<(i64, Label)>> {
    let rows: Vec<(i64, i64, i64, String, String, String)> = sqlx::query_as(
        "SELECT il.issue_id, l.id, l.repo_id, l.name, l.colour, l.description FROM issue_labels il JOIN labels l ON l.id = il.label_id JOIN issues i ON i.id = il.issue_id WHERE i.repo_id = $1 ORDER BY l.name",
    )
    .bind(repo_id)
    .fetch_all(pool)
    .await?;
    Ok(rows
        .into_iter()
        .map(|(issue_id, id, repo_id, name, colour, description)| (issue_id, Label { id, repo_id, name, colour, description }))
        .collect())
}

pub async fn proposal_labels(pool: &Pool, proposal_id: i64) -> sqlx::Result<Vec<Label>> {
    sqlx::query_as("SELECT l.* FROM labels l JOIN proposal_labels pl ON pl.label_id = l.id WHERE pl.proposal_id = $1 ORDER BY l.name")
        .bind(proposal_id)
        .fetch_all(pool)
        .await
}

pub async fn set_proposal_label(pool: &Pool, proposal_id: i64, label_id: i64, on: bool) -> sqlx::Result<()> {
    if on {
        sqlx::query("INSERT OR IGNORE INTO proposal_labels (proposal_id, label_id) VALUES ($1, $2)")
            .bind(proposal_id)
            .bind(label_id)
            .execute(pool)
            .await?;
    } else {
        sqlx::query("DELETE FROM proposal_labels WHERE proposal_id = $1 AND label_id = $2")
            .bind(proposal_id)
            .bind(label_id)
            .execute(pool)
            .await?;
    }
    Ok(())
}

// --------------------------------------------------------------- assignees

pub async fn assignees(pool: &Pool, issue_id: i64) -> sqlx::Result<Vec<String>> {
    sqlx::query_scalar(
        "SELECT a.username FROM accounts a JOIN issue_assignees ia ON ia.account_id = a.id WHERE ia.issue_id = $1 ORDER BY a.username",
    )
    .bind(issue_id)
    .fetch_all(pool)
    .await
}

pub async fn set_assignee(pool: &Pool, issue_id: i64, account_id: i64, on: bool) -> sqlx::Result<()> {
    if on {
        sqlx::query("INSERT OR IGNORE INTO issue_assignees (issue_id, account_id) VALUES ($1, $2)")
            .bind(issue_id)
            .bind(account_id)
            .execute(pool)
            .await?;
    } else {
        sqlx::query("DELETE FROM issue_assignees WHERE issue_id = $1 AND account_id = $2")
            .bind(issue_id)
            .bind(account_id)
            .execute(pool)
            .await?;
    }
    Ok(())
}

/// Assignees of every issue of a repository, for the list page.
pub async fn assignees_by_issue(pool: &Pool, repo_id: i64) -> sqlx::Result<Vec<(i64, String)>> {
    sqlx::query_as("SELECT ia.issue_id, a.username FROM issue_assignees ia JOIN accounts a ON a.id = ia.account_id JOIN issues i ON i.id = ia.issue_id WHERE i.repo_id = $1")
        .bind(repo_id)
        .fetch_all(pool)
        .await
}

// -------------------------------------------------------------- milestones

pub async fn milestones(pool: &Pool, repo_id: i64) -> sqlx::Result<Vec<Milestone>> {
    sqlx::query_as("SELECT * FROM milestones WHERE repo_id = $1 ORDER BY state, due_ms, title").bind(repo_id).fetch_all(pool).await
}

pub async fn milestone(pool: &Pool, id: i64) -> sqlx::Result<Option<Milestone>> {
    sqlx::query_as("SELECT * FROM milestones WHERE id = $1").bind(id).fetch_optional(pool).await
}

pub async fn upsert_milestone(pool: &Pool, repo_id: i64, title: &str, description: &str, due_ms: Option<i64>) -> sqlx::Result<Milestone> {
    sqlx::query_as("INSERT INTO milestones (repo_id, title, description, due_ms) VALUES ($1, $2, $3, $4) ON CONFLICT (repo_id, title) DO UPDATE SET description = excluded.description, due_ms = excluded.due_ms RETURNING *")
        .bind(repo_id)
        .bind(title)
        .bind(description)
        .bind(due_ms)
        .fetch_one(pool)
        .await
}

/// Change a milestone's title, description and due date.
pub async fn update_milestone(pool: &Pool, id: i64, title: &str, description: &str, due_ms: Option<i64>) -> sqlx::Result<()> {
    sqlx::query("UPDATE milestones SET title = $1, description = $2, due_ms = $3 WHERE id = $4")
        .bind(title)
        .bind(description)
        .bind(due_ms)
        .bind(id)
        .execute(pool)
        .await?;
    Ok(())
}

pub async fn set_milestone_state(pool: &Pool, id: i64, state: &str) -> sqlx::Result<()> {
    sqlx::query("UPDATE milestones SET state = $1 WHERE id = $2").bind(state).bind(id).execute(pool).await?;
    Ok(())
}

/// `(open, closed)` issue counts per milestone.
pub async fn milestone_counts(pool: &Pool, milestone_id: i64) -> sqlx::Result<(i64, i64)> {
    let open: i64 = sqlx::query_scalar("SELECT COUNT(*) FROM issues WHERE milestone_id = $1 AND state = 'open'")
        .bind(milestone_id)
        .fetch_one(pool)
        .await?;
    let closed: i64 = sqlx::query_scalar("SELECT COUNT(*) FROM issues WHERE milestone_id = $1 AND state = 'closed'")
        .bind(milestone_id)
        .fetch_one(pool)
        .await?;
    Ok((open, closed))
}