use super::*;
use crate::core::db::{create_connection, run_migrations};
use std::path::Path;

fn setup_test_db() -> Connection {
    let conn = create_connection(Path::new(":memory:")).unwrap();
    run_migrations(&conn).unwrap();
    conn
}

fn seed_project_issue_mr(conn: &Connection) -> (i64, i64, i64) {
    conn.execute(
        "INSERT INTO projects (id, gitlab_project_id, path_with_namespace, web_url, created_at, updated_at)
         VALUES (1, 100, 'group/repo', 'https://gitlab.example.com/group/repo', 1000, 2000)",
        [],
    )
    .unwrap();

    conn.execute(
        "INSERT INTO issues (id, gitlab_id, iid, project_id, title, state, created_at, updated_at, last_seen_at)
         VALUES (1, 200, 10, 1, 'Test issue', 'closed', 1000, 2000, 2000)",
        [],
    )
    .unwrap();

    conn.execute(
        "INSERT INTO merge_requests (id, gitlab_id, iid, project_id, title, state, created_at, updated_at, last_seen_at, source_branch, target_branch)
         VALUES (1, 300, 5, 1, 'Test MR', 'merged', 1000, 2000, 2000, 'feature', 'main')",
        [],
    )
    .unwrap();

    (1, 1, 1)
}

#[test]
fn test_extract_refs_from_state_events_basic() {
    let conn = setup_test_db();
    let (project_id, issue_id, mr_id) = seed_project_issue_mr(&conn);

    conn.execute(
        "INSERT INTO resource_state_events
         (gitlab_id, project_id, issue_id, merge_request_id, state,
          created_at, source_merge_request_iid)
         VALUES (1, ?1, ?2, NULL, 'closed', 3000, 5)",
        rusqlite::params![project_id, issue_id],
    )
    .unwrap();

    let count = extract_refs_from_state_events(&conn, project_id).unwrap();
    assert_eq!(count, 1, "Should insert exactly one reference");

    let (src_type, src_id, tgt_type, tgt_id, ref_type, method): (
        String,
        i64,
        String,
        i64,
        String,
        String,
    ) = conn
        .query_row(
            "SELECT source_entity_type, source_entity_id,
                    target_entity_type, target_entity_id,
                    reference_type, source_method
             FROM entity_references WHERE project_id = ?1",
            [project_id],
            |row| {
                Ok((
                    row.get(0)?,
                    row.get(1)?,
                    row.get(2)?,
                    row.get(3)?,
                    row.get(4)?,
                    row.get(5)?,
                ))
            },
        )
        .unwrap();

    assert_eq!(src_type, "merge_request");
    assert_eq!(src_id, mr_id, "Source should be the MR's local DB id");
    assert_eq!(tgt_type, "issue");
    assert_eq!(tgt_id, issue_id, "Target should be the issue's local DB id");
    assert_eq!(ref_type, "closes");
    assert_eq!(method, "api");
}

#[test]
fn test_extract_refs_dedup_with_closes_issues() {
    let conn = setup_test_db();
    let (project_id, issue_id, mr_id) = seed_project_issue_mr(&conn);

    conn.execute(
        "INSERT INTO entity_references
         (project_id, source_entity_type, source_entity_id,
          target_entity_type, target_entity_id,
          reference_type, source_method, created_at)
         VALUES (?1, 'merge_request', ?2, 'issue', ?3, 'closes', 'api', 3000)",
        rusqlite::params![project_id, mr_id, issue_id],
    )
    .unwrap();

    conn.execute(
        "INSERT INTO resource_state_events
         (gitlab_id, project_id, issue_id, merge_request_id, state,
          created_at, source_merge_request_iid)
         VALUES (1, ?1, ?2, NULL, 'closed', 3000, 5)",
        rusqlite::params![project_id, issue_id],
    )
    .unwrap();

    let count = extract_refs_from_state_events(&conn, project_id).unwrap();
    assert_eq!(count, 0, "Should not insert duplicate reference");

    let total: i64 = conn
        .query_row(
            "SELECT COUNT(*) FROM entity_references WHERE project_id = ?1",
            [project_id],
            |row| row.get(0),
        )
        .unwrap();
    assert_eq!(total, 1, "Should still have exactly one reference");
}

#[test]
fn test_extract_refs_no_source_mr() {
    let conn = setup_test_db();
    let (project_id, issue_id, _mr_id) = seed_project_issue_mr(&conn);

    conn.execute(
        "INSERT INTO resource_state_events
         (gitlab_id, project_id, issue_id, merge_request_id, state,
          created_at, source_merge_request_iid)
         VALUES (1, ?1, ?2, NULL, 'closed', 3000, NULL)",
        rusqlite::params![project_id, issue_id],
    )
    .unwrap();

    let count = extract_refs_from_state_events(&conn, project_id).unwrap();
    assert_eq!(count, 0, "Should not create refs when no source MR");
}

#[test]
fn test_extract_refs_mr_not_synced() {
    let conn = setup_test_db();
    let (project_id, issue_id, _mr_id) = seed_project_issue_mr(&conn);

    conn.execute(
        "INSERT INTO resource_state_events
         (gitlab_id, project_id, issue_id, merge_request_id, state,
          created_at, source_merge_request_iid)
         VALUES (2, ?1, ?2, NULL, 'closed', 3000, 999)",
        rusqlite::params![project_id, issue_id],
    )
    .unwrap();

    let count = extract_refs_from_state_events(&conn, project_id).unwrap();
    assert_eq!(
        count, 0,
        "Should not create ref when MR is not synced locally"
    );
}

#[test]
fn test_extract_refs_idempotent() {
    let conn = setup_test_db();
    let (project_id, issue_id, _mr_id) = seed_project_issue_mr(&conn);

    conn.execute(
        "INSERT INTO resource_state_events
         (gitlab_id, project_id, issue_id, merge_request_id, state,
          created_at, source_merge_request_iid)
         VALUES (1, ?1, ?2, NULL, 'closed', 3000, 5)",
        rusqlite::params![project_id, issue_id],
    )
    .unwrap();

    let count1 = extract_refs_from_state_events(&conn, project_id).unwrap();
    assert_eq!(count1, 1);

    let count2 = extract_refs_from_state_events(&conn, project_id).unwrap();
    assert_eq!(count2, 0, "Second run should insert nothing (idempotent)");
}

#[test]
fn test_extract_refs_multiple_events_same_mr_issue() {
    let conn = setup_test_db();
    let (project_id, issue_id, _mr_id) = seed_project_issue_mr(&conn);

    conn.execute(
        "INSERT INTO resource_state_events
         (gitlab_id, project_id, issue_id, merge_request_id, state,
          created_at, source_merge_request_iid)
         VALUES (1, ?1, ?2, NULL, 'closed', 3000, 5)",
        rusqlite::params![project_id, issue_id],
    )
    .unwrap();
    conn.execute(
        "INSERT INTO resource_state_events
         (gitlab_id, project_id, issue_id, merge_request_id, state,
          created_at, source_merge_request_iid)
         VALUES (2, ?1, ?2, NULL, 'closed', 4000, 5)",
        rusqlite::params![project_id, issue_id],
    )
    .unwrap();

    let count = extract_refs_from_state_events(&conn, project_id).unwrap();
    assert!(count <= 2, "At most 2 inserts attempted");

    let total: i64 = conn
        .query_row(
            "SELECT COUNT(*) FROM entity_references WHERE project_id = ?1",
            [project_id],
            |row| row.get(0),
        )
        .unwrap();
    assert_eq!(
        total, 1,
        "Only one unique reference should exist for same MR->issue pair"
    );
}

#[test]
fn test_extract_refs_scoped_to_project() {
    let conn = setup_test_db();
    seed_project_issue_mr(&conn);

    conn.execute(
        "INSERT INTO projects (id, gitlab_project_id, path_with_namespace, web_url, created_at, updated_at)
         VALUES (2, 101, 'group/other', 'https://gitlab.example.com/group/other', 1000, 2000)",
        [],
    )
    .unwrap();
    conn.execute(
        "INSERT INTO issues (id, gitlab_id, iid, project_id, title, state, created_at, updated_at, last_seen_at)
         VALUES (2, 201, 10, 2, 'Other issue', 'closed', 1000, 2000, 2000)",
        [],
    )
    .unwrap();
    conn.execute(
        "INSERT INTO merge_requests (id, gitlab_id, iid, project_id, title, state, created_at, updated_at, last_seen_at, source_branch, target_branch)
         VALUES (2, 301, 5, 2, 'Other MR', 'merged', 1000, 2000, 2000, 'feature', 'main')",
        [],
    )
    .unwrap();

    conn.execute(
        "INSERT INTO resource_state_events
         (gitlab_id, project_id, issue_id, merge_request_id, state,
          created_at, source_merge_request_iid)
         VALUES (1, 1, 1, NULL, 'closed', 3000, 5)",
        [],
    )
    .unwrap();
    conn.execute(
        "INSERT INTO resource_state_events
         (gitlab_id, project_id, issue_id, merge_request_id, state,
          created_at, source_merge_request_iid)
         VALUES (2, 2, 2, NULL, 'closed', 3000, 5)",
        [],
    )
    .unwrap();

    let count = extract_refs_from_state_events(&conn, 1).unwrap();
    assert_eq!(count, 1);

    let total: i64 = conn
        .query_row("SELECT COUNT(*) FROM entity_references", [], |row| {
            row.get(0)
        })
        .unwrap();
    assert_eq!(total, 1, "Only project 1 refs should be created");
}

#[test]
fn test_insert_entity_reference_creates_row() {
    let conn = setup_test_db();
    let (project_id, issue_id, mr_id) = seed_project_issue_mr(&conn);

    let ref_ = EntityReference {
        project_id,
        source_entity_type: "merge_request",
        source_entity_id: mr_id,
        target_entity_type: "issue",
        target_entity_id: Some(issue_id),
        target_project_path: None,
        target_entity_iid: None,
        reference_type: "closes",
        source_method: "api",
    };

    let inserted = insert_entity_reference(&conn, &ref_).unwrap();
    assert!(inserted);

    let count = count_references_for_source(&conn, "merge_request", mr_id).unwrap();
    assert_eq!(count, 1);
}

#[test]
fn test_insert_entity_reference_idempotent() {
    let conn = setup_test_db();
    let (project_id, issue_id, mr_id) = seed_project_issue_mr(&conn);

    let ref_ = EntityReference {
        project_id,
        source_entity_type: "merge_request",
        source_entity_id: mr_id,
        target_entity_type: "issue",
        target_entity_id: Some(issue_id),
        target_project_path: None,
        target_entity_iid: None,
        reference_type: "closes",
        source_method: "api",
    };

    let first = insert_entity_reference(&conn, &ref_).unwrap();
    assert!(first);

    let second = insert_entity_reference(&conn, &ref_).unwrap();
    assert!(!second, "Duplicate insert should be ignored");

    let count = count_references_for_source(&conn, "merge_request", mr_id).unwrap();
    assert_eq!(count, 1, "Still just one reference");
}

#[test]
fn test_insert_entity_reference_cross_project_unresolved() {
    let conn = setup_test_db();
    let (project_id, _issue_id, mr_id) = seed_project_issue_mr(&conn);

    let ref_ = EntityReference {
        project_id,
        source_entity_type: "merge_request",
        source_entity_id: mr_id,
        target_entity_type: "issue",
        target_entity_id: None,
        target_project_path: Some("other-group/other-project"),
        target_entity_iid: Some(99),
        reference_type: "closes",
        source_method: "api",
    };

    let inserted = insert_entity_reference(&conn, &ref_).unwrap();
    assert!(inserted);

    let (target_id, target_path, target_iid): (Option<i64>, Option<String>, Option<i64>) = conn
        .query_row(
            "SELECT target_entity_id, target_project_path, target_entity_iid \
             FROM entity_references WHERE source_entity_id = ?1",
            [mr_id],
            |row| Ok((row.get(0)?, row.get(1)?, row.get(2)?)),
        )
        .unwrap();

    assert!(target_id.is_none());
    assert_eq!(target_path, Some("other-group/other-project".to_string()));
    assert_eq!(target_iid, Some(99));
}

#[test]
fn test_insert_multiple_closes_references() {
    let conn = setup_test_db();
    let (project_id, issue_id, mr_id) = seed_project_issue_mr(&conn);

    conn.execute(
        "INSERT INTO issues (id, gitlab_id, iid, project_id, title, state, created_at, updated_at, last_seen_at)
         VALUES (10, 210, 11, ?1, 'Second issue', 'opened', 1000, 2000, 2000)",
        rusqlite::params![project_id],
    )
    .unwrap();
    let issue_id_2 = 10i64;

    for target_id in [issue_id, issue_id_2] {
        let ref_ = EntityReference {
            project_id,
            source_entity_type: "merge_request",
            source_entity_id: mr_id,
            target_entity_type: "issue",
            target_entity_id: Some(target_id),
            target_project_path: None,
            target_entity_iid: None,
            reference_type: "closes",
            source_method: "api",
        };
        insert_entity_reference(&conn, &ref_).unwrap();
    }

    let count = count_references_for_source(&conn, "merge_request", mr_id).unwrap();
    assert_eq!(count, 2);
}

#[test]
fn test_resolve_issue_local_id_found() {
    let conn = setup_test_db();
    let (project_id, issue_id, _mr_id) = seed_project_issue_mr(&conn);

    let resolved = resolve_issue_local_id(&conn, project_id, 10).unwrap();
    assert_eq!(resolved, Some(issue_id));
}

#[test]
fn test_resolve_issue_local_id_not_found() {
    let conn = setup_test_db();
    let (project_id, _issue_id, _mr_id) = seed_project_issue_mr(&conn);

    let resolved = resolve_issue_local_id(&conn, project_id, 999).unwrap();
    assert!(resolved.is_none());
}

#[test]
fn test_resolve_project_path_found() {
    let conn = setup_test_db();
    seed_project_issue_mr(&conn);

    let path = resolve_project_path(&conn, 100).unwrap();
    assert_eq!(path, Some("group/repo".to_string()));
}

#[test]
fn test_resolve_project_path_not_found() {
    let conn = setup_test_db();

    let path = resolve_project_path(&conn, 999).unwrap();
    assert!(path.is_none());
}