import AppKit

func osa(_ src: String) throws -> NSAppleEventDescriptor {
    return try DispatchQueue.main.sync {
        guard let script = NSAppleScript(source: "with timeout of 10 seconds\n\(src)\nend timeout") else {
            throw ToolError("AppleScript did not compile")
        }
        var err: NSDictionary?
        let r = script.executeAndReturnError(&err)
        if let err {
            throw ToolError("AppleScript: \(err[NSAppleScript.errorMessage] ?? err)")
        }
        return r
    }
}

func quote(_ s: String) -> String {
    return "\"" + s.replacingOccurrences(of: "\\", with: "\\\\").replacingOccurrences(of: "\"", with: "\\\"") + "\""
}

func jsString(_ s: String) -> String {
    let d = try! JSONSerialization.data(withJSONObject: s, options: .fragmentsAllowed)
    return String(decoding: d, as: UTF8.self)
}

struct TabTarget {
    let window: Int
    let tab: Int?

    var spec: String {
        if let tab {
            return "tab \(tab) of window \(window)"
        }
        return "current tab of window \(window)"
    }
}

func js(_ code: String, _ t: TabTarget) throws -> String {
    let r = try osa("tell application \"Orion\" to do JavaScript \(quote(code)) in \(t.spec)")
    return r.stringValue ?? "undefined"
}

func orionWindow(_ index: Int) throws -> Int {
    return Int(try osa("tell application \"Orion\" to get id of window \(index)").int32Value)
}

func tabs() throws -> String {
    let src = """
    tell application "Orion"
        set out to ""
        repeat with wi from 1 to count of windows
            try
                set w to window wi
                repeat with ti from 1 to count of tabs of w
                    set t to tab ti of w
                    set out to out & wi & " " & ti & " " & (name of t) & " | " & (URL of t) & linefeed
                end repeat
            end try
        end repeat
        return out
    end tell
    """
    return "window tab title | url\n" + (try osa(src).stringValue ?? "")
}

func waitLoaded(_ t: TabTarget, timeout: Double) async throws -> String {
    let start = Date()
    await pause(300)
    while Date().timeIntervalSince(start) < timeout {
        if (try? js("document.readyState", t)) == "complete" {
            return String(format: "loaded after %.1fs", Date().timeIntervalSince(start))
        }
        await pause(200)
    }
    return String(format: "still loading after %.1fs", timeout)
}

func browserTool(_ args: [String: Any]) async throws -> [Content] {
    let op = try args.require("op", args.string)
    let win = args.int("window") ?? 1
    var target = TabTarget(window: win, tab: args.int("tab"))
    let lock = op == "tabs" && !args.bool("capture") ? nil : try await lockInput()
    defer {
        if let lock {
            close(lock)
        }
    }
    var log: [String] = []
    switch op {
    case "tabs":
        log.append(try tabs())
    case "navigate":
        let url = try args.require("url", args.string)
        if args.bool("new_tab") {
            _ = try osa("tell application \"Orion\" to tell window \(win) to set current tab to (make new tab with properties {URL:\(quote(url))})")
            target = TabTarget(window: win, tab: nil)
        } else {
            _ = try osa("tell application \"Orion\" to set URL of \(target.spec) to \(quote(url))")
        }
        log.append(try await waitLoaded(target, timeout: Double(try args.ms("timeout_ms") ?? 15000) / 1000))
        log.append(try js("document.title + ' | ' + location.href", target))
    case "js":
        log.append(try js(try args.require("code", args.string), target))
    case "select":
        let tab = try args.require("tab", args.int)
        _ = try osa("tell application \"Orion\" to set current tab of window \(win) to tab \(tab) of window \(win)")
        log.append("selected tab \(tab)")
        target = TabTarget(window: win, tab: nil)
    case "close":
        let tab = try args.require("tab", args.int)
        _ = try osa("tell application \"Orion\" to close tab \(tab) of window \(win)")
        log.append("closed tab \(tab)")
        target = TabTarget(window: win, tab: nil)
    default:
        throw ToolError("unknown op \(op.debugDescription)")
    }
    let present: (String) async throws -> Bool = { needle in
        (try? js("String((document.title + '\\n' + (document.body ? document.body.innerText : '')).toLowerCase().includes(\(jsString(needle.lowercased()))))", target)) == "true"
    }
    if let note = try await waitFor(args, acted: false, present) {
        log.append(note)
    }
    var out: [Content] = []
    if args.bool("capture") {
        if let tab = target.tab {
            _ = try osa("tell application \"Orion\" to set current tab of window \(win) to tab \(tab) of window \(win)")
            log.append("selected tab \(tab) to capture it")
            await pause(300)
        }
        let id = try orionWindow(win)
        let shot = try await capture(window: id, display: nil, crop: args.dict("crop"), maxEdge: args.double("max_edge") ?? 1568)
        log.append(shot.note)
        out.append(.png(shot.png))
    }
    return [.text(log.joined(separator: "\n"))] + out
}