import XCTest
@testable import LChatCore

// 🤖 Sidebar snippet (previewText) must mirror the web (previewText in
// shell.js): a non-image attachment reads as a file chip, not "📷 Photo".
final class PreviewTextTests: XCTestCase {
    private func att(_ name: String, _ type: String?) -> Attachment {
        Attachment(id: "b", name: name, type: type)
    }

    func testTextTakesPrecedence() {
        var p = MessagePayload()
        p.text = "  hello   world \n"
        p.attachments = [att("photo.jpg", "image/jpeg")]
        XCTAssertEqual(previewText(kind: "dm", payload: p), "hello world")
    }

    func testSingleImage() {
        var p = MessagePayload()
        p.attachments = [att("photo.jpg", "image/jpeg")]
        XCTAssertEqual(previewText(kind: "dm", payload: p), "📷 Photo")
    }

    func testMultipleImages() {
        var p = MessagePayload()
        p.attachments = [att("a.jpg", "image/jpeg"), att("b.png", "image/png")]
        XCTAssertEqual(previewText(kind: "dm", payload: p), "📷 2 photos")
    }

    func testSingleFileIsNotAPhoto() {
        var p = MessagePayload()
        p.attachments = [att("report.docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document")]
        XCTAssertEqual(previewText(kind: "dm", payload: p), "📎 report.docx")
    }

    func testMultipleFiles() {
        var p = MessagePayload()
        p.attachments = [att("a.docx", "application/msword"), att("b.pdf", "application/pdf")]
        XCTAssertEqual(previewText(kind: "dm", payload: p), "📎 2 files")
    }

    func testMixedImageAndFileFallsToFiles() {
        var p = MessagePayload()
        p.attachments = [att("a.jpg", "image/jpeg"), att("b.pdf", "application/pdf")]
        XCTAssertEqual(previewText(kind: "dm", payload: p), "📎 2 files")
    }

    // A typeless attachment (legacy) isn't an image → file chip with its name.
    func testUntypedAttachment() {
        var p = MessagePayload()
        p.attachments = [att("mystery.bin", nil)]
        XCTAssertEqual(previewText(kind: "dm", payload: p), "📎 mystery.bin")
    }

    func testGroupPrefix() {
        var p = MessagePayload()
        p.name = "Ada"
        p.attachments = [att("report.docx", "application/msword")]
        XCTAssertEqual(previewText(kind: "group", payload: p), "Ada: 📎 report.docx")
    }

    // A reaction has no text of its own — the row used to go blank (in a group,
    // a bare "Ada: "). It says what happened instead, quoting the snippet the
    // reacting client stamped inside the ciphertext. Web twin: reactionLine in
    // format.js + the reaction branch in shell.js previewText.
    private func reaction(_ name: String, _ emoji: String, on: Bool, target: String?) -> MessagePayload {
        var p = MessagePayload()
        p.type = "reaction"
        p.name = name
        p.emoji = emoji
        p.on = on
        p.targetSid = 12345
        p.targetText = target
        return p
    }

    func testReactionQuotesItsTarget() {
        let p = reaction("Ada", "👍", on: true, target: "buy milk")
        XCTAssertEqual(previewText(kind: "dm", payload: p), "Ada reacted 👍 to “buy milk”")
    }

    // It names the actor itself, so the group prefix never doubles up.
    func testReactionTakesNoGroupPrefix() {
        let p = reaction("Ada", "👍", on: true, target: "buy milk")
        XCTAssertEqual(previewText(kind: "group", payload: p), "Ada reacted 👍 to “buy milk”")
    }

    func testMyOwnReactionSaysYou() {
        let p = reaction("Ada", "🎉", on: true, target: "shipped it")
        XCTAssertEqual(previewText(kind: "group", payload: p, mine: true), "You reacted 🎉 to “shipped it”")
    }

    // An un-react speaks too: on reload this event is all the sidebar has, so
    // silence would mean a different row after a refresh than the one shown live.
    func testUnReactSpeaks() {
        let p = reaction("Bob", "❤️", on: false, target: "shipped it 🎉")
        XCTAssertEqual(previewText(kind: "dm", payload: p), "Bob removed ❤️ from “shipped it 🎉”")
    }

    // Reactions from clients that predate targetText (and every reaction
    // already in a database) carry no snippet — the bare form still reads.
    func testReactionWithoutASnippet() {
        XCTAssertEqual(previewText(kind: "dm", payload: reaction("Ada", "👍", on: true, target: nil)),
                       "Ada reacted 👍")
        XCTAssertEqual(previewText(kind: "dm", payload: reaction("Ada", "👍", on: false, target: nil)),
                       "Ada removed 👍")
    }

    func testReactionQuoteIsClamped() {
        let p = reaction("Ada", "👍", on: true, target: String(repeating: "a", count: 200))
        let line = previewText(kind: "dm", payload: p)
        XCTAssertTrue(line.hasPrefix("Ada reacted 👍 to “"))
        XCTAssertTrue(line.hasSuffix("…”"))
        XCTAssertLessThan(line.count, 70, "the sidebar line stays one line's worth")
    }

    // The caller resolves the actor by uid (ThreadStore's displayLabels — my
    // name for them, #577), and that wins over the payload's snapshot. Without
    // it, a reaction from a device that stamped no screen name — common on real
    // data — reads "Someone reacted 👍".
    func testActorResolvesByUidOverThePayloadName() {
        var p = reaction("", "😂", on: true, target: nil)
        p.name = ""
        XCTAssertEqual(previewText(kind: "group", payload: p, actor: "Paul"), "Paul reacted 😂")
    }

    func testResolvedActorBeatsAStalePayloadName() {
        let p = reaction("Old Name", "👍", on: true, target: "buy milk")
        XCTAssertEqual(previewText(kind: "dm", payload: p, actor: "My Name For Them"),
                       "My Name For Them reacted 👍 to “buy milk”")
    }

    // Nobody to resolve (they left the space, and the payload named no one).
    func testReactionWithoutANameSaysSomeone() {
        var p = reaction("", "👍", on: true, target: "buy milk")
        p.name = nil
        XCTAssertEqual(previewText(kind: "dm", payload: p), "Someone reacted 👍 to “buy milk”")
    }

    // The group prefix takes the same by-uid resolution as the reaction line:
    // my name for them, so the row survives a rename and never renders a bare
    // ": hello" for a sender whose device stamped no screen name. Web twin:
    // previewText in shell.js resolves `who` once and uses it for both.
    func testGroupPrefixUsesTheResolvedActor() {
        var p = MessagePayload()
        p.name = "Old Name"
        p.text = "hello"
        XCTAssertEqual(previewText(kind: "group", payload: p, actor: "My Name For Them"),
                       "My Name For Them: hello")
    }

    func testGroupPrefixFallsBackToThePayloadName() {
        var p = MessagePayload()
        p.name = "Ada"
        p.text = "hello"
        XCTAssertEqual(previewText(kind: "group", payload: p), "Ada: hello")
    }

    // Nothing to resolve and nothing stamped: no stray colon.
    func testGroupPrefixIsSkippedWithNoNameAtAll() {
        var p = MessagePayload()
        p.text = "hello"
        XCTAssertEqual(previewText(kind: "group", payload: p), "hello")
    }

    // An action line names its own actor — prefixing it doubles the name up.
    func testActionLineTakesNoGroupPrefix() {
        var p = MessagePayload()
        p.name = "Ada"
        p.text = "waves"
        p.action = true
        XCTAssertEqual(previewText(kind: "group", payload: p, actor: "Ada"), "waves")
    }
}