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feat: add simplified OT engine
+53
+53
internal/collaboration/ot.go
+53
internal/collaboration/ot.go
···
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package collaboration
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import "sync"
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type OTEngine struct {
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mu sync.Mutex
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documentText string
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version int
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}
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func NewOTEngine(initialText string) *OTEngine {
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return &OTEngine{
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documentText: initialText,
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version: 0,
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}
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}
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type Operation struct {
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From int `json:"from"`
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To int `json:"to"`
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Insert string `json:"insert"`
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Author string `json:"author"`
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}
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func (ot *OTEngine) Apply(op Operation) string {
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ot.mu.Lock()
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defer ot.mu.Unlock()
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if op.To > len(ot.documentText) {
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op.To = len(ot.documentText)
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}
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if op.From > len(ot.documentText) {
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op.From = len(ot.documentText)
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}
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newText := ot.documentText[:op.From] + op.Insert + ot.documentText[op.To:]
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ot.documentText = newText
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ot.version++
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return ot.documentText
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}
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func (ot *OTEngine) GetText() string {
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ot.mu.Lock()
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defer ot.mu.Unlock()
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return ot.documentText
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}
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func (ot *OTEngine) GetVersion() int {
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ot.mu.Lock()
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defer ot.mu.Unlock()
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return ot.version
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}