Have actually implemented useful commands for reading/writing CSV files

commandmap.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"bitbucket.org/lmika/ted-v2/ui"
+	"fmt"
 )
 
 const (
@@ -53,6 +54,23 @@ func (cm *CommandMapping) KeyMapping(key rune) *Command {
 	return cm.KeyMappings[key]
 }
 
+// Evaluate a command
+func (cm *CommandMapping) Eval(ctx *CommandContext, expr string) error {
+	// TODO: Use propper expression language here
+	cmd := cm.Commands[expr]
+	if cmd != nil {
+		return cmd.Do(ctx)
+	}
+
+	return fmt.Errorf("no such command: %v", expr)
+}
+
+func (cm *CommandMapping) DoEval(ctx *CommandContext, expr string) {
+	if err := cm.Eval(ctx, expr); err != nil {
+		ctx.ShowError(err)
+	}
+}
+
 // Registers the standard view navigation commands.  These commands require the frame
 func (cm *CommandMapping) RegisterViewCommands() {
 	cm.Define("move-down", "Moves the cursor down one row", "", gridNavOperation(func(grid *ui.Grid) { grid.MoveBy(0, 1) }))
@@ -88,7 +106,7 @@ func (cm *CommandMapping) RegisterViewCommands() {
 
 	cm.Define("enter-command", "Enter command", "", func(ctx *CommandContext) error {
 		ctx.Frame().Prompt(":", func(res string) {
-			ctx.Frame().Message("Command = " + res)
+			cm.DoEval(ctx, res)
 		})
 		return nil
 	})
@@ -104,10 +122,38 @@ func (cm *CommandMapping) RegisterViewCommands() {
 		return nil
 	})
 
+	cm.Define("save", "Save current file", "", func(ctx *CommandContext) error {
+		wSource, isWSource := ctx.Session().Source.(WritableModelSource)
+		if !isWSource {
+			return fmt.Errorf("model is not writable")
+		}
+
+		if err := wSource.Write(ctx.Session().Model); err != nil {
+			return err
+		}
+
+		ctx.Frame().Message("Wrote " + wSource.String())
+		return nil
+	})
+
 	cm.Define("quit", "Quit TED", "", func(ctx *CommandContext) error {
 		ctx.Session().UIManager.Shutdown()
 		return nil
 	})
+
+	cm.Define("save-and-quit", "Save current file, then quit", "", func(ctx *CommandContext) error {
+		if err := cm.Eval(ctx, "save"); err != nil {
+			return nil
+		}
+
+		return cm.Eval(ctx, "quit")
+	})
+
+
+	// Aliases
+	cm.Commands["w"] = cm.Command("save")
+	cm.Commands["q"] = cm.Command("quit")
+	cm.Commands["wq"] = cm.Command("save-and-quit")
 }
 
 // Registers the standard view key bindings.  These commands require the frame
@@ -133,8 +179,6 @@ func (cm *CommandMapping) RegisterViewKeyBindings() {
 	cm.MapKey('e', cm.Command("set-cell"))
 
 	cm.MapKey(':', cm.Command("enter-command"))
-
-	cm.MapKey('q', cm.Command("quit"))
 }
 
 // A nativation command factory.  This will perform the passed in operation with the current grid and

frame.go

@@ -102,16 +102,20 @@ func (frame *Frame) Prompt(prompt string, callback func(res string)) {
 	frame.textEntry.Prompt = prompt
 	frame.textEntry.SetValue("")
 
+	frame.textEntry.OnCancel = frame.exitEntryMode
 	frame.textEntry.OnEntry = func(res string) {
-		frame.textEntry.OnEntry = nil
-		frame.setMode(GridMode)
-
+		frame.exitEntryMode()
 		callback(res)
 	}
 
 	frame.setMode(EntryMode)
 }
 
+func (frame *Frame) exitEntryMode() {
+	frame.textEntry.OnEntry = nil
+	frame.setMode(GridMode)
+}
+
 // Show a message.  This will switch the bottom to the messageView and select the frame
 func (frame *Frame) ShowMessage(msg string) {
 	frame.messageView.Text = msg

main.go

@@ -11,11 +11,9 @@ func main() {
 	}
 	defer uiManager.Close()
 
-	model := &StdModel{}
-	model.Resize(5, 5)
-
 	frame := NewFrame(uiManager)
-	NewSession(uiManager, frame, model)
+	session := NewSession(uiManager, frame, CsvFileModelSource{"test.csv"})
+	session.LoadFromSource()
 
 	uiManager.SetRootComponent(frame.RootComponent())
 	frame.enterMode(GridMode)

model.go

@@ -3,20 +3,13 @@
  */
 package main
 
-
-/**
- * An abstract model interface.  At a minimum, models must be read only.
- */
+// An abstract model interface.  At a minimum, models must be read only.
 type Model interface {
     
-    /**
-     * The dimensions of the model (height, width).
-     */
+    // The dimensions of the model (height, width).
     Dimensions()     (int, int)
 
-    /**
-     * Returns the value of a cell.
-     */
+    // Returns the value of a cell
     CellValue(r, c int) string
 }
 
@@ -29,4 +22,7 @@ type RWModel interface {
 
     // Sets the cell value
     SetCellValue(r, c int, value string)
+
+    // Returns true if the model has been modified in some way
+    IsDirty() bool
 }

modelsource.go

@@ -0,0 +1,91 @@
+package main
+
+import (
+	"path/filepath"
+	"os"
+	"encoding/csv"
+	"io"
+)
+
+// ModelSource is a source of models.  At a minimum, it must be able to read models.
+type ModelSource interface {
+	// Describes the source
+	String() string
+
+	// Read the model from the given source
+	Read() (Model, error)
+}
+
+// Writable models take a model and write it to the source
+type WritableModelSource interface {
+	ModelSource
+
+	// Write writes a model to the source
+	Write(m Model) error
+}
+
+// A model source backed by a CSV file
+type CsvFileModelSource struct {
+	Filename string
+}
+
+// Describes the source
+func (s CsvFileModelSource) String() string {
+	return filepath.Base(s.Filename)
+}
+
+// Read the model from the given source
+func (s CsvFileModelSource) Read() (Model, error) {
+	f, err := os.Open(s.Filename)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	model := new(StdModel)
+	r := csv.NewReader(f)
+	for {
+		record, err := r.Read()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return nil, err
+		}
+
+		model.appendStr(record)
+	}
+
+	model.dirty = false
+	return model, nil
+}
+
+func (s CsvFileModelSource) Write(m Model) error {
+	f, err := os.Create(s.Filename)
+	if err != nil {
+		return err
+	}
+
+	w := csv.NewWriter(f)
+
+	rows, cols := m.Dimensions()
+
+	for r := 0; r < rows; r++ {
+		record := make([]string, cols)		// Reuse the record slice
+		for c := 0; c < cols; c++ {
+			record[c] =  m.CellValue(r, c)
+		}
+		if err := w.Write(record); err != nil {
+			f.Close()
+			return err
+		}
+	}
+
+	w.Flush()
+	if err := w.Error(); err != nil {
+		f.Close()
+		return err
+	}
+
+	return f.Close()
+}

session.go

@@ -6,14 +6,16 @@ import "bitbucket.org/lmika/ted-v2/ui"
 // the interaction between the two and the user.
 type Session struct {
 	Model     Model
+	Source    ModelSource
 	Frame     *Frame
 	Commands  *CommandMapping
 	UIManager *ui.Ui
 }
 
-func NewSession(uiManager *ui.Ui, frame *Frame, model Model) *Session {
+func NewSession(uiManager *ui.Ui, frame *Frame, source ModelSource) *Session {
 	session := &Session{
-		Model:     model,
+		Model:     nil,
+		Source:	   source,
 		Frame:     frame,
 		Commands:  NewCommandMapping(),
 		UIManager: uiManager,
@@ -30,6 +32,17 @@ func NewSession(uiManager *ui.Ui, frame *Frame, model Model) *Session {
 	return session
 }
 
+// LoadFromSource loads the model from the source, replacing the existing model
+func (session *Session) LoadFromSource() error {
+	newModel, err := session.Source.Read()
+	if err != nil {
+		return err
+	}
+
+	session.Model = newModel
+	return nil
+}
+
 // Input from the frame
 func (session *Session) KeyPressed(key rune, mod int) {
 	// Add the mod key modifier
@@ -59,6 +72,13 @@ func (scc *CommandContext) Frame() *Frame {
 	return scc.session.Frame
 }
 
+// Error displays an error if err is not nil
+func (scc *CommandContext) ShowError(err error) {
+	if err != nil {
+		scc.Frame().Message(err.Error())
+	}
+}
+
 // Session grid model
 type SessionGridModel struct {
 	Session *Session

stdmodel.go

@@ -8,6 +8,7 @@ type Cell struct {
 // Standard model
 type StdModel struct {
 	Cells [][]Cell
+	dirty bool
 }
 
 /**
@@ -47,6 +48,7 @@ func (sm *StdModel) Resize(rs, cs int) {
 	}
 
 	sm.Cells = newRows
+	sm.dirty = true
 }
 
 // Sets the cell value
@@ -55,4 +57,36 @@ func (sm *StdModel) SetCellValue(r, c int, value string) {
 	if (r >= 0) && (c >= 0) && (r < rs) && (c < cs) {
 		sm.Cells[r][c].Value = value
 	}
+	sm.dirty = true
+}
+
+// appendStr appends the model with the given row
+func (sm *StdModel) appendStr(row []string) {
+	if len(sm.Cells) == 0 {
+		cells := sm.strSliceToCell(row, len(row))
+		sm.Cells = [][]Cell{ cells }
+		return
+	}
+
+	cols := len(sm.Cells[0])
+	if len(row) > cols {
+		sm.Resize(len(sm.Cells), len(row))
+		cols = len(sm.Cells[0])
+	}
+	cells := sm.strSliceToCell(row, cols)
+	sm.Cells = append(sm.Cells, cells)
+}
+
+func (sm *StdModel) strSliceToCell(row []string, targetRowLen int) []Cell {
+	cs := make([]Cell, targetRowLen)
+	for i, c := range row {
+		if i < targetRowLen {
+			cs[i].Value = c
+		}
+	}
+	return cs
+}
+
+func (sm *StdModel) IsDirty() bool {
+	return sm.dirty
 }

ui/driver.go

@@ -87,6 +87,7 @@ const (
 	KeyBackspace  = KeyCtrlH
 	KeyBackspace2 = KeyCtrl8
 	KeyEnter      = KeyCtrlM
+	KeyEsc        = KeyCtrl3
 )
 
 // The type of events supported by the driver
@@ -116,7 +117,6 @@ type Event struct {
 
 // The terminal driver interface.
 type Driver interface {
-
 	// Initializes the driver.  Returns an error if there was an error
 	Init() error
 

ui/stdcomps.go

@@ -2,7 +2,9 @@
 
 package ui
 
-import "unicode"
+import (
+	"unicode"
+	)
 
 // A text component.  This simply renders a text string.
 type TextView struct {
@@ -58,6 +60,9 @@ type TextEntry struct {
 
 	// Called when the user presses Enter
 	OnEntry func(val string)
+
+	// Called when the user presses Esc or CtrlC
+	OnCancel func()
 }
 
 func (te *TextEntry) Remeasure(w, h int) (int, int) {
@@ -127,13 +132,18 @@ func (te *TextEntry) KeyPressed(key rune, mod int) {
 	} else if key == KeyDelete {
 		te.removeCharAtPos(te.cursorOffset)
 	} else if key == KeyEnter {
-		//panic("Entered text: '" + te.value + "'")
 		if te.OnEntry != nil {
 			te.OnEntry(te.value)
 		}
+	} else if key == KeyCtrlC {
+		if te.OnCancel != nil {
+			te.OnCancel()
 		}
 	}
 
+	//panic(fmt.Sprintf("Entered key: '%x', mod: '%x'", key, mod))
+}
+
 // Backspace
 func (te *TextEntry) backspace() {
 	te.removeCharAtPos(te.cursorOffset - 1)