Open what the core can read, and say when it cannot

CHANGELOG.md

@@ -17,6 +17,19 @@ open: **a second build under the same version goes under the already cut
 heading, not back under `Unreleased`.** Date the heading and add its compare link
 once the version tag exists.
 
+## [Unreleased]
+
+### Added
+
+- A zip file opens and lists what is inside. Tapping an entry shows it.
+- Photos and text files the reader used to refuse now open.
+
+### Changed
+
+- A file that will not open says so, and offers to write to us when something
+  went wrong on our side.
+- The app no longer offers itself for music and films.
+
 ## [1.42]
 
 ### Added

OpenDocumentReader/Constants.swift

@@ -12,6 +12,9 @@ enum Constants {
     /// Which of the house ad's rotations comes next.
     static let key_house_ad_index = "houseAdIndex"
 
+    /// The address the "file will not open" message names.
+    static let supportEmail = "support@opendocument.app"
+
     /// ODR Pro on the App Store. This is the *paid* app: on iOS that is `at.tomtasche.reader`,
     /// while on Android the same bundle id names the free one.
     static let proAppStoreId = 1_452_061_743

OpenDocumentReader/CoreWrapper.swift

@@ -77,14 +77,13 @@ private func selectViews(_ views: [HtmlView], _ documentType: DocumentType) -> [
     }
 }
 
-/// A csv is a *text* file to odrcore that also loads as a spreadsheet, so it
-/// answers `isDocumentFile` with false and `asDocumentFile()` fails on it.
-private func isCsv(_ file: DecodedFile) -> Bool { file.fileType == .commaSeparatedValues }
-
 @objc final class CoreWrapper: NSObject {
     @objc private(set) var pageNames: [String] = []
     @objc private(set) var pageURLs: [URL] = []
 
+    /// Whether odrcore saw only a container, so the page is a listing of what is inside it.
+    @objc private(set) var isArchive = false
+
     /// Whether `backTranslate` has a document to apply an edit to. Only a
     /// document that said it takes one is kept, so having it *is* the answer.
     @objc var isEditable: Bool { lock.withLock { document != nil } }
@@ -105,6 +104,7 @@ private func isCsv(_ file: DecodedFile) -> Bool { file.fileType == .commaSeparat
         pageNames = []
         pageURLs = []
         document = nil
+        isArchive = false
 
         let fileTypes = (try? DecodedFile.listFileTypes(path: inputPath)) ?? []
         guard !fileTypes.isEmpty else {
@@ -126,11 +126,14 @@ private func isCsv(_ file: DecodedFile) -> Bool { file.fileType == .commaSeparat
             }
         }
 
-        // odrcore also translates images, media and fonts, but only into an
-        // `<img>` or a `<video>` the web view decodes anyway. Those go to the
-        // system instead, through the fallback in `DocumentViewController`.
-        guard file.isDocumentFile || file.isPdfFile || isCsv(file) else {
-            throw coreWrapperError(.unsupportedFileType, "not a document, a pdf or a csv")
+        guard Odr.capabilities(fileType: file.fileType).translateHtml else {
+            throw coreWrapperError(.unsupportedFileType, "odrcore does not render this file type")
+        }
+
+        // odrcore calls a file it recognises as nothing else text, so an unnamed
+        // charset means the bytes are not text at all
+        if file.isTextFile, (try? file.asTextFile())?.charset == nil {
+            throw coreWrapperError(.unsupportedFileType, "odrcore could not name a charset")
         }
 
         // the same answers OpenDocument.droid gives odrcore, so a document is
@@ -170,10 +173,8 @@ private func isCsv(_ file: DecodedFile) -> Bool { file.fileType == .commaSeparat
             service = try HtmlTranslator.translate(
                 document: document, cachePath: cachePath, config: config)
         } else {
-            // a csv and a pdf have no document behind them to open or to edit.
-            // `.unknown` keeps the combined view for both; not `.spreadsheet`,
-            // though a csv is one, because that asks for a tab per sheet and a
-            // csv's single sheet is called "csv"
+            // nothing to edit, and `.unknown` keeps the single view each of
+            // these has - `.spreadsheet` would ask for a tab per sheet
             documentType = .unknown
             openedDocument = nil
             service = try HtmlTranslator.translate(
@@ -193,6 +194,7 @@ private func isCsv(_ file: DecodedFile) -> Bool { file.fileType == .commaSeparat
         // a document whose pages were never served
         self.document = openedDocument
 
+        isArchive = file.isArchiveFile
         pageNames = views.map(\.name)
         pageURLs = views.map { base.appendingPathComponent($0.path) }
     }

OpenDocumentReader/Document.swift

@@ -48,6 +48,8 @@ class Document: UIDocument {
     public var webview: WKWebView?
 
     public var isOdf = false
+    /// Whether the page is a listing of an archive - see `CoreWrapper.isArchive`.
+    public var isArchive = false
     /// Whether the menu should offer to edit this one - see `CoreWrapper.isEditable`.
     public var isEditable = false
     private var wasPageCountAnnounced = false
@@ -62,6 +64,7 @@ class Document: UIDocument {
         loadProgress.completedUnitCount = 2
 
         isOdf = false
+        isArchive = false
         isEditable = false
         result = nil
         pageURLs = nil
@@ -91,6 +94,7 @@ class Document: UIDocument {
         }
 
         isOdf = true
+        isArchive = coreWrapper.isArchive
         isEditable = coreWrapper.isEditable
 
         loadProgress.completedUnitCount = loadProgress.totalUnitCount