30 lines
547 B
JavaScript
30 lines
547 B
JavaScript
class CommandHistory {
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constructor() {
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this.history = [];
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this.pointer = -1;
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}
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addCommand(cmd) {
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this.history.push(cmd);
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this.pointer = this.history.length;
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}
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getPreviousCommand() {
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if (this.pointer >= 0) {
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this.pointer--;
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}
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return this.history[this.pointer];
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}
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getNextCommand() {
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if (this.pointer >= this.history.length) {
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this.pointer = this.history.length - 1;
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return '';
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}
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this.pointer++;
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return this.history[this.pointer];
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}
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}
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module.exports = CommandHistory;
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