// Generates a slice of rows with all of the data required for display.
func (navigator *Navigator) View(maxRows int) *view.Buffer {
var start, end, size int
var entrySize string
// Return the current directory path as the status.
status := [2]string{navigator.CurrentPath(), ""}
// Append a percentage to the status line, if
// we're still calculating directory sizes.
if navigator.pendingCalculations > 0 {
entryCount := len(navigator.entries)
status[1] = fmt.Sprintf("(%d%%)", (entryCount-navigator.pendingCalculations)*100/entryCount)
} else {
avail := int64(navigator.availableBytes())
total := int64(navigator.totalBytes())
status[1] = fmt.Sprintf("%v available (%v%% used)", view.Size(avail), (total-avail)*100/total)
}
// Create a slice with a size that is the lesser of the entry count and maxRows.
entryCount := len(navigator.Entries())
if maxRows > entryCount {
size = entryCount
} else {
size = maxRows
}
viewData := make([]view.Row, size, size)
// Don't bother going any further if there are no entries to work with.
if size == 0 {
return &view.Buffer{Rows: viewData, Status: status}
}
// Deleting an entry can result in the cached view range indices
// being out of bounds; correct that if it has occurred.
if navigator.viewDataIndices[1] > entryCount {
navigator.viewDataIndices[1] = entryCount
}
// Determine the range of entries to return.
if navigator.viewDataIndices[1] != 0 && navigator.viewDataIndices[0] <= navigator.SelectedIndex() &&
navigator.SelectedIndex() < navigator.viewDataIndices[1] {
// The selected entry is still visible in the slice last returned. Return
// the same range of entries to keep the view as consistent as possible.
start, end = navigator.viewDataIndices[0], navigator.viewDataIndices[1]
} else if navigator.viewDataIndices[1] != 0 && navigator.SelectedIndex() < navigator.viewDataIndices[0] {
// The selected entry is beneath the range of entries previously returned.
// Shift the range down just enough to include the selected entry.
start = navigator.SelectedIndex()
end = navigator.SelectedIndex() + size
} else if navigator.SelectedIndex() >= size {
// The selected entry is either above the previously returned range, or
// this function hasn't been called for the current directory yet. Either way,
// it would be outside of the returned range if we started at zero, so return
// a range with it at the top.
start = navigator.SelectedIndex() + 1 - size
end = navigator.SelectedIndex() + 1
} else {
// Use the range starting at index 0.
start = 0
end = size
}
// Copy the navigator entries' names and
// formatted sizes into the slice we'll return.
for i, entry := range navigator.Entries()[start:end] {
highlight := i+int(start) == int(navigator.SelectedIndex())
// Add a trailing slash to the name
// if the entry is a directory.
var name string
if entry.IsDirectory {
name = entry.Name + "/"
} else {
name = entry.Name
}
if entry.SizeCalculated {
entrySize = view.Size(entry.Size)
} else {
entrySize = "Calculating..."
}
viewData[i] = view.Row{name, entrySize, highlight, entry.IsDirectory}
}
// Store the indices used to generate the view data.
navigator.viewDataIndices = [2]int{start, end}
return &view.Buffer{Rows: viewData, Status: status}
}
Describe("Status Line", func() {
Context("when all calculations have completed", func() {
BeforeEach(func() {
// FIXME: This calculation gets stuck at 75%.
// Hijack the navigator to simulate calculation completion.
navigator.pendingCalculations = 0
})
It("returns the current directory path as its first element", func() {
Expect(buffer.Status[0]).To(Equal(navigator.CurrentPath()))
})
It("returns disk/partition space statistics as its second element", func() {
avail := int64(navigator.availableBytes())
total := int64(navigator.totalBytes())
status := fmt.Sprintf("%v available (%v%% used)", view.Size(avail), (total-avail)*100/total)
Expect(buffer.Status[1]).To(Equal(status))
})
})
})
Context("maxRows is set to 1", func() {
BeforeEach(func() {
maxRows = 1
})
It("returns a buffer with the right number of rows", func() {
Expect(len(buffer.Rows)).To(BeEquivalentTo(maxRows))
})
It("stores the proper view data indices", func() {