from PyQt5.QtWidgets import QApplication, QTextEdit
from PyQt5.QtGui import QSyntaxHighlighter, QTextCharFormat, QFont, QFontMetrics
from PyQt5.QtCore import QRegularExpression, Qt

class CodeEditor(QTextEdit):
    def __init__(self, text:str=""):
        super().__init__()
        self.setFont(QFont("Courier New", 12))
        fontMetrics = QFontMetrics(self.font())
        tabWidth = 4 * fontMetrics.width(' ')  # Calculate the width of a tab
        self.setTabStopWidth(tabWidth)
        self.setPlainText(text)
        self.highlighter = CodeHighlighter(self.document())
        self.highlighter.rehighlight()

    def paste(self):
        super().paste()
        self.highlighter.rehighlight()

class CodeHighlighter(QSyntaxHighlighter):
    def __init__(self, document):
        super().__init__(document)
        self.highlightingRules = []

        # 定义 JSON 高亮规则
        self.keyFormat = QTextCharFormat()
        self.keyFormat.setForeground(Qt.GlobalColor.darkBlue)
        self.keyFormat.setFontWeight(QFont.Bold)

        self.valueFormat = QTextCharFormat()
        self.valueFormat.setForeground(Qt.GlobalColor.darkGreen)

        self.boolFormat = QTextCharFormat()
        self.boolFormat.setForeground(Qt.GlobalColor.red)

        self.numberFormat = QTextCharFormat()
        self.numberFormat.setForeground(Qt.GlobalColor.darkCyan)

        # 创建蓝色格式
        blueFormat = QTextCharFormat()
        blueFormat.setForeground(Qt.GlobalColor.blue)

        self.rules = [
            (QRegularExpression(r'\b(true|false|null)\b'), self.boolFormat),
            (QRegularExpression(r'\b(-?\d+\.?\d*)\b'), self.numberFormat),
            (QRegularExpression(r'\{'), blueFormat),
            (QRegularExpression(r'\}'), blueFormat),
            (QRegularExpression(r'\['), blueFormat),
            (QRegularExpression(r'\]'), blueFormat),
            (QRegularExpression(r'\"(\\.|[^"\\])*\"'), self.valueFormat),
            (QRegularExpression(r'\b(\w+)\s*:'), self.keyFormat)
        ]

    def highlightBlock(self, text):
        for pattern, format in self.rules:
            expression = QRegularExpression(pattern)
            matchIterator = expression.globalMatch(text)
            while matchIterator.hasNext():
                match = matchIterator.next()
                self.setFormat(match.capturedStart(), match.capturedLength(), format)

if __name__ == "__main__":
    import sys
    app = QApplication(sys.argv)
    editor = CodeEditor()
    editor.show()
    sys.exit(app.exec_())