import { test, expect, describe } from 'bun:test'
import { ScopeTracker } from './scopeTracker'
import { TextDocument } from 'vscode-languageserver-textdocument'
import { parser } from '../../../src/parser/shrimp'
import * as Terms from '../../../src/parser/shrimp.terms'

describe('ScopeTracker', () => {
  test('top-level assignment is in scope', () => {
    const code = 'x = 5\necho x'
    const { tree, tracker } = parseAndGetScope(code)

    // Find the 'x' identifier in 'echo x'
    const identifiers: any[] = []
    tree.topNode.cursor().iterate((node: any) => {
      if (node.type.id === Terms.Identifier) {
        identifiers.push(node.node)
      }
    })

    // Second identifier should be the 'x' in 'echo x'
    const xInEcho = identifiers[1]
    expect(xInEcho).toBeDefined()
    expect(tracker.isInScope('x', xInEcho)).toBe(true)
  })

  test('undeclared variable is not in scope', () => {
    const code = 'echo x'
    const { tree, tracker } = parseAndGetScope(code)

    // Find the 'x' identifier
    let xNode: any = null
    tree.topNode.cursor().iterate((node: any) => {
      if (node.type.id === Terms.Identifier) {
        xNode = node.node
      }
    })

    expect(xNode).toBeDefined()
    expect(tracker.isInScope('x', xNode)).toBe(false)
  })

  test('function parameter is in scope inside function', () => {
    const code = `greet = do name:
  echo name
end`
    const { tree, tracker } = parseAndGetScope(code)

    // Find all identifiers
    const identifiers: any[] = []
    tree.topNode.cursor().iterate((node: any) => {
      if (node.type.id === Terms.Identifier) {
        identifiers.push(node.node)
      }
    })

    // Find the 'name' in 'echo name' (should be last identifier)
    const nameInEcho = identifiers[identifiers.length - 1]
    expect(tracker.isInScope('name', nameInEcho)).toBe(true)
  })

  test('assignment before usage is in scope', () => {
    const code = `x = 5
y = 10
echo x y`
    const { tree, tracker } = parseAndGetScope(code)

    // Find identifiers
    const identifiers: any[] = []
    tree.topNode.cursor().iterate((node: any) => {
      if (node.type.id === Terms.Identifier) {
        identifiers.push(node.node)
      }
    })

    // Last two identifiers should be 'x' and 'y' in 'echo x y'
    const xInEcho = identifiers[identifiers.length - 2]
    const yInEcho = identifiers[identifiers.length - 1]

    expect(tracker.isInScope('x', xInEcho)).toBe(true)
    expect(tracker.isInScope('y', yInEcho)).toBe(true)
  })

  test('assignment after usage is not in scope', () => {
    const code = `echo x
x = 5`
    const { tree, tracker } = parseAndGetScope(code)

    // Find the first 'x' identifier (in echo)
    let xNode: any = null
    tree.topNode.cursor().iterate((node: any) => {
      if (node.type.id === Terms.Identifier && !xNode) {
        xNode = node.node
      }
    })

    expect(tracker.isInScope('x', xNode)).toBe(false)
  })

  test('nested function has access to outer scope', () => {
    const code = `x = 5
greet = do:
  echo x
end`
    const { tree, tracker } = parseAndGetScope(code)

    // Find all identifiers
    const identifiers: any[] = []
    tree.topNode.cursor().iterate((node: any) => {
      if (node.type.id === Terms.Identifier) {
        identifiers.push(node.node)
      }
    })

    // Find the 'x' in 'echo x' (should be last identifier)
    const xInEcho = identifiers[identifiers.length - 1]
    expect(tracker.isInScope('x', xInEcho)).toBe(true)
  })

  test('inner function parameter shadows outer variable', () => {
    const code = `x = 5
greet = do x:
  echo x
end`
    const { tree, tracker } = parseAndGetScope(code)

    // Find all identifiers
    const identifiers: any[] = []
    tree.topNode.cursor().iterate((node: any) => {
      if (node.type.id === Terms.Identifier) {
        identifiers.push(node.node)
      }
    })

    // The 'x' in 'echo x' should have 'x' in scope (from parameter)
    const xInEcho = identifiers[identifiers.length - 1]
    expect(tracker.isInScope('x', xInEcho)).toBe(true)
  })
})

const parseAndGetScope = (code: string) => {
  const document = TextDocument.create('test://test.sh', 'shrimp', 1, code)
  const tree = parser.parse(code)
  const tracker = new ScopeTracker(document)
  return { document, tree, tracker }
}