//
//  ConsoleSmokeTests.swift
//  Metrika
//
//  Author:  Simon-Pierre Boucher
//  Contact: contact@spboucher.ai
//  Copyright © 2026 Simon-Pierre Boucher. All rights reserved.
//

import XCTest

/// XCUITest smoke (CLAUDE.md §9): launch the app, load a sample dataset,
/// run a regression, and assert the output table appears in the console.
///
/// The sandboxed app cannot read files staged by the test runner (and its
/// container may be recreated between runs), so the dataset travels via
/// `METRIKA_UITEST_CSV` in the launch environment; the app writes it into
/// its own container and `use`s it on startup.
///
/// SwiftUI `Text` exposes content through the accessibility **value**
/// attribute, so all queries predicate on `value`, not `label`.
final class ConsoleSmokeTests: XCTestCase {

    private func staticText(
        containing needle: String, in app: XCUIApplication
    ) -> XCUIElement {
        app.staticTexts.matching(
            NSPredicate(format: "value CONTAINS %@", needle)
        ).firstMatch
    }

    func testLoadDatasetAndRegress() throws {
        continueAfterFailure = false

        let app = XCUIApplication()
        app.launchEnvironment["METRIKA_UITEST_CSV"] = """
        revenue,price,region,firm_id
        120.5,10.2,1,1
        98.3,12.1,1,1
        143.2,9.8,2,2
        110.0,11.5,2,2
        155.9,8.9,3,3
        101.2,12.8,3,3
        133.4,10.1,1,4
        88.7,13.5,2,4
        149.1,9.2,3,5
        115.6,11.0,1,5
        """
        app.launch()

        // Startup hook loads the dataset.
        let loaded = staticText(containing: "10 observations, 4 variables", in: app)
        XCTAssertTrue(loaded.waitForExistence(timeout: 10), "dataset did not load")

        let input = app.textFields.firstMatch
        XCTAssertTrue(input.waitForExistence(timeout: 5), "command field missing")
        input.click()
        input.typeText("gen log_rev = ln(revenue)\n")
        input.typeText("reg log_rev price, robust\n")

        // Regression output: robust banner and coefficient table.
        let banner = staticText(containing: "Linear regression (robust)", in: app)
        XCTAssertTrue(banner.waitForExistence(timeout: 10), "regression output missing")
        XCTAssertTrue(
            staticText(containing: "Coefficient", in: app).exists,
            "coefficient table missing"
        )

        // Sidebar reflects the generated variable.
        let sidebar = staticText(containing: "log_rev", in: app)
        XCTAssertTrue(sidebar.waitForExistence(timeout: 5), "sidebar missing log_rev")
    }

    func testMetalScatterPath() throws {
        continueAfterFailure = false

        let app = XCUIApplication()
        app.launchEnvironment["METRIKA_METAL_THRESHOLD"] = "3"
        app.launchEnvironment["METRIKA_UITEST_CSV"] = """
        revenue,price
        120.5,10.2
        98.3,12.1
        143.2,9.8
        110.0,11.5
        155.9,8.9
        101.2,12.8
        """
        app.launch()
        XCTAssertTrue(
            staticText(containing: "6 observations", in: app).waitForExistence(timeout: 10),
            "dataset did not load"
        )

        let input = app.textFields.firstMatch
        input.click()
        input.typeText("scatter revenue price\n")

        // 6 points > threshold 3 → the Metal pane takes over. The pane is
        // exposed through its accessibility label.
        let metalPane = app.descendants(matching: .any).matching(
            NSPredicate(format: "label CONTAINS %@ OR value CONTAINS %@",
                        "Metal scatter", "Metal scatter")
        ).firstMatch
        XCTAssertTrue(metalPane.waitForExistence(timeout: 10), "Metal scatter pane missing")
    }

    func testDataBrowserAndDoFile() throws {
        continueAfterFailure = false

        let app = XCUIApplication()
        app.launchEnvironment["METRIKA_UITEST_CSV"] = """
        revenue,price,region
        120.5,10.2,1
        98.3,12.1,1
        143.2,9.8,2
        110.0,11.5,2
        155.9,8.9,3
        """
        app.launch()
        XCTAssertTrue(
            staticText(containing: "5 observations", in: app).waitForExistence(timeout: 10),
            "dataset did not load"
        )

        // Data pane: grid renders, filter compiles to an if-expression.
        switchPane(to: "Data", in: app)
        let grid = app.tables.firstMatch
        XCTAssertTrue(grid.waitForExistence(timeout: 5), "data grid missing")

        let filter = app.textFields.firstMatch
        XCTAssertTrue(filter.waitForExistence(timeout: 5), "filter bar missing")
        filter.click()
        filter.typeText("revenue > 115 & region != 3\n")
        XCTAssertTrue(
            staticText(containing: "2 of 5 observations", in: app)
                .waitForExistence(timeout: 5),
            "filter did not narrow rows"
        )

        // Do-file pane: type a script and run it with ⌘R.
        switchPane(to: "Do-file", in: app)
        let editor = app.textViews.firstMatch
        XCTAssertTrue(editor.waitForExistence(timeout: 5), "editor missing")
        editor.click()
        editor.typeText("gen high = revenue > 120\ncount if high == 1")
        app.typeKey("r", modifierFlags: .command)

        // Output lands in the shared console.
        switchPane(to: "Console", in: app)
        XCTAssertTrue(
            staticText(containing: "do-file (2 lines)", in: app)
                .waitForExistence(timeout: 10),
            "do-file output missing from console"
        )
        // Sidebar picked up the do-file's generated variable.
        XCTAssertTrue(
            staticText(containing: "high", in: app).waitForExistence(timeout: 5),
            "sidebar missing variable generated by do-file"
        )

        // Manual pane: overview page and a command entry render.
        switchPane(to: "Manual", in: app)
        XCTAssertTrue(
            staticText(containing: "How Metrika works", in: app)
                .waitForExistence(timeout: 5),
            "manual overview missing"
        )
        let regressEntry = app.staticTexts["regress"].firstMatch
        XCTAssertTrue(regressEntry.waitForExistence(timeout: 5), "regress entry missing")
        regressEntry.click()
        XCTAssertTrue(
            staticText(containing: "Ordinary least squares", in: app)
                .waitForExistence(timeout: 5),
            "regress manual page missing"
        )
    }

    /// The pane switcher is a segmented picker in the toolbar; SwiftUI
    /// exposes segments as radio buttons (with a button fallback).
    private func switchPane(to name: String, in app: XCUIApplication) {
        let radio = app.radioButtons[name]
        if radio.waitForExistence(timeout: 3) {
            radio.click()
            return
        }
        app.buttons[name].firstMatch.click()
    }
}