import std/unittest
import std/os
import std/strutils
import std/times
import std/monotimes
import barabadb/core/types
import barabadb/query/executor as qexec
import barabadb/query/parser
import barabadb/query/ast
import barabadb/storage/lsm

proc execSql(ctx: qexec.ExecutionContext, sql: string): qexec.ExecResult =
  qexec.executeQuery(ctx, parse(sql))

# ---------------------------------------------------------------------------
suite "JOIN execution":
  var db: LSMTree
  var ctx: qexec.ExecutionContext
  var testDir: string

  setup:
    testDir = getTempDir() / "baradb_join_test_" & $getCurrentProcessId() & "_" & $getMonoTime().ticks
    createDir(testDir)
    db = newLSMTree(testDir)
    ctx = qexec.newExecutionContext(db)
    discard execSql(ctx, "CREATE TABLE users (id INT, name TEXT)")
    discard execSql(ctx, "CREATE TABLE orders (id INT, user_id INT, total REAL)")
    discard execSql(ctx, "INSERT INTO users (id, name) VALUES (1, 'Alice')")
    discard execSql(ctx, "INSERT INTO users (id, name) VALUES (2, 'Bob')")
    discard execSql(ctx, "INSERT INTO orders (id, user_id, total) VALUES (10, 1, 99.5)")
    discard execSql(ctx, "INSERT INTO orders (id, user_id, total) VALUES (20, 1, 23.0)")
    discard execSql(ctx, "INSERT INTO orders (id, user_id, total) VALUES (30, 3, 150.0)")

  teardown:
    removeDir(testDir)

  test "INNER JOIN returns matching rows only":
    let r = execSql(ctx, "SELECT * FROM users u JOIN orders o ON u.id = o.user_id")
    check r.rows.len == 2
    check r.rows[0]["name"] == "Alice"
    check r.rows[0]["total"] == "99.5"

  test "LEFT JOIN keeps unmatched left rows":
    let r = execSql(ctx, "SELECT * FROM users u LEFT JOIN orders o ON u.id = o.user_id")
    check r.rows.len == 3
    check r.rows[0]["name"] == "Alice"
    check r.rows[1]["name"] == "Alice"
    check r.rows[2]["name"] == "Bob"
    check r.rows[2]["total"] == ""  # NULL represented as empty string

  test "RIGHT JOIN keeps unmatched right rows":
    let r = execSql(ctx, "SELECT * FROM users u RIGHT JOIN orders o ON u.id = o.user_id")
    check r.rows.len == 3
    check r.rows[2]["id"] == "30"
    check r.rows[2]["name"] == ""  # NULL
    check r.rows[2]["total"] == "150.0"

  test "FULL JOIN keeps all rows":
    let r = execSql(ctx, "SELECT * FROM users u FULL JOIN orders o ON u.id = o.user_id")
    check r.rows.len == 4

  test "CROSS JOIN cartesian product":
    let r = execSql(ctx, "SELECT * FROM users u CROSS JOIN orders o")
    check r.rows.len == 6

  test "aliased column projection":
    let r = execSql(ctx, "SELECT u.name, o.total FROM users u JOIN orders o ON u.id = o.user_id")
    check r.rows.len == 2
    check r.rows[0]["name"] == "Alice"
    check r.rows[0]["total"] == "99.5"
    check "id" notin r.rows[0]

  test "count after FULL JOIN":
    let r = execSql(ctx, "SELECT COUNT(*) AS cnt FROM users u FULL JOIN orders o ON u.id = o.user_id")
    check r.rows.len == 1
    check r.rows[0]["cnt"] == "4"

  test "count after CROSS JOIN":
    let r = execSql(ctx, "SELECT COUNT(*) AS cnt FROM users u CROSS JOIN orders o")
    check r.rows[0]["cnt"] == "6"