ReadingListFetchSpec.swift

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

import Foundation

// TODO This should really use NSURLComponents to build up the query part. And not string ops.

class ReadingListFetchSpec {
    var queryString: String

    init(queryString: String) {
        self.queryString = queryString
    }

    func getURL(serviceURL: URL) -> URL? {
        if var components = URLComponents(url: serviceURL, resolvingAgainstBaseURL: true) {
            components.query = queryString
            return components.url
        }
        return nil
    }

    func getURL(serviceURL: URL, path: String) -> URL? {
        if var components = URLComponents(url: serviceURL, resolvingAgainstBaseURL: true) {
            components.path = path
            components.query = queryString
            return components.url
        }
        return nil
    }

    // This should really generate a dictionary of values that we can pass to NSURLComponents instead of building the query string by hand

    class Builder {
        var buffer: String = ""
        var first = true

        func build() -> ReadingListFetchSpec {
            return ReadingListFetchSpec(queryString: buffer)
        }

        fileprivate func ampersand() {
            if first {
                first = false
                return
            }
            buffer += "&"
        }

        func setUnread(_ unread: Bool) -> Builder {
            ampersand()
            buffer += "unread="
            buffer += unread ? "true" : "false"
            return self
        }

        func setStatus(_ status: String, not: Bool) -> Builder {
            ampersand()
            if not {
                buffer += "not_"
            }
            buffer += "status="
            buffer += status
            return self
        }

        fileprivate func qualifyAttribute(_ attribute: String, withQualifier qualifier: String, value: String) -> Builder {
            ampersand()
            buffer += qualifier
            buffer += attribute
            buffer += "="
            buffer += value
            return self
        }

        func setMinAttribute(_ attribute: String, value: String) -> Builder {
            _ = qualifyAttribute(attribute, withQualifier: "min_", value: value)
            return self
        }

        func setMaxAttribute(_ attribute: String, value: String) -> Builder {
            _ = qualifyAttribute(attribute, withQualifier: "max_", value: value)
            return self
        }
    }
}