import Foundation
import SaplingCore
import SaplingEditor
import XCTest

@MainActor
final class DocumentSessionStoreTests: XCTestCase {
    func testOpeningSameFileReusesExistingSession() throws {
        let url = URL(fileURLWithPath: "/tmp/Sapling/Notes.md")
        var loadCount = 0
        let store = DocumentSessionStore()

        let first = try store.openDocument(at: url) { url in
            loadCount += 1
            return MarkdownDocument(url: url, title: "Notes", content: "# Notes")
        }

        let second = try store.openDocument(at: url.standardizedFileURL) { url in
            loadCount += 1
            return MarkdownDocument(url: url, title: "Notes", content: "# Reloaded")
        }

        XCTAssertIdentical(first, second)
        XCTAssertIdentical(store.activeSession, first)
        XCTAssertEqual(store.sessions.count, 1)
        XCTAssertEqual(loadCount, 1)
        XCTAssertEqual(first.viewModel.document.content, "# Notes")
    }

    func testOpeningDifferentFilesCreatesSeparateSessionsAndActivatesLatest() throws {
        let firstURL = URL(fileURLWithPath: "/tmp/Sapling/One.md")
        let secondURL = URL(fileURLWithPath: "/tmp/Sapling/Two.md")
        let store = DocumentSessionStore()

        let first = try store.openDocument(at: firstURL) { url in
            MarkdownDocument(url: url, title: "One", content: "# One")
        }
        let second = try store.openDocument(at: secondURL) { url in
            MarkdownDocument(url: url, title: "Two", content: "# Two")
        }

        XCTAssertEqual(store.sessions.count, 2)
        XCTAssertIdentical(store.activeSession, second)

        XCTAssertTrue(store.activateDocument(at: firstURL))
        XCTAssertIdentical(store.activeSession, first)
    }

    func testActivateMissingDocumentReturnsFalse() {
        let store = DocumentSessionStore()

        XCTAssertFalse(store.activateDocument(at: URL(fileURLWithPath: "/tmp/missing.md")))
        XCTAssertNil(store.activeSession)
    }
}