"""
Progress Panel - Right sidebar with progress tracking and statistics
"""

from PyQt5.QtWidgets import (
    QWidget, QVBoxLayout, QHBoxLayout, QLabel,
    QProgressBar, QPushButton, QFrame, QScrollArea
)
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QFont

from app import config
from app.models import Course


class ProgressPanel(QWidget):
    """Right sidebar panel with progress statistics and tracking"""

    def __init__(self, course: Course, parent=None):
        super().__init__(parent)
        self.course = course

        self.init_ui()

    def init_ui(self):
        """Initialize the UI components"""
        # Main layout
        main_layout = QVBoxLayout(self)
        main_layout.setContentsMargins(10, 10, 10, 10)
        main_layout.setSpacing(10)

        # Title
        title = QLabel("Your Progress")
        title.setStyleSheet(f"font-size: 14pt; font-weight: bold; color: {config.COLOR_PRIMARY};")
        main_layout.addWidget(title)

        # Scroll area for content
        scroll = QScrollArea()
        scroll.setWidgetResizable(True)
        scroll.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
        scroll.setFrameShape(QFrame.NoFrame)

        # Content widget
        content_widget = QWidget()
        layout = QVBoxLayout(content_widget)
        layout.setContentsMargins(0, 0, 5, 0)
        layout.setSpacing(15)

        # === Overall Progress Section ===
        layout.addWidget(self._create_section_header("Overall Progress"))

        self.overall_progress_bar = QProgressBar()
        self.overall_progress_bar.setStyleSheet(f"""
            QProgressBar {{
                border: 2px solid {config.COLOR_PRIMARY};
                border-radius: 5px;
                text-align: center;
                height: 25px;
            }}
            QProgressBar::chunk {{
                background-color: {config.COLOR_SUCCESS};
            }}
        """)
        layout.addWidget(self.overall_progress_bar)

        self.overall_stats_label = QLabel("0 / 30 lessons completed")
        self.overall_stats_label.setStyleSheet("font-size: 10pt; color: #666;")
        layout.addWidget(self.overall_stats_label)

        layout.addWidget(self._create_separator())

        # === Points and Level Section ===
        layout.addWidget(self._create_section_header("Points & Level"))

        points_layout = QHBoxLayout()
        self.points_label = QLabel("0 pts")
        self.points_label.setStyleSheet(f"font-size: 24pt; font-weight: bold; color: {config.COLOR_WARNING};")
        points_layout.addWidget(self.points_label)
        points_layout.addStretch()
        layout.addLayout(points_layout)

        self.level_label = QLabel("Level 1: Novice")
        self.level_label.setStyleSheet("font-size: 11pt; color: #666;")
        layout.addWidget(self.level_label)

        self.level_progress_bar = QProgressBar()
        self.level_progress_bar.setStyleSheet(f"""
            QProgressBar {{
                border: 1px solid #ccc;
                border-radius: 3px;
                text-align: center;
                height: 15px;
            }}
            QProgressBar::chunk {{
                background-color: {config.COLOR_WARNING};
            }}
        """)
        layout.addWidget(self.level_progress_bar)

        layout.addWidget(self._create_separator())

        # === Part Progress Section ===
        layout.addWidget(self._create_section_header("Progress by Part"))

        self.part_progress_widgets = []
        for part in self.course.parts:
            part_widget = self._create_part_progress(part.number, part.title, 0)
            self.part_progress_widgets.append(part_widget)
            layout.addWidget(part_widget)

        layout.addWidget(self._create_separator())

        # === Study Stats Section ===
        layout.addWidget(self._create_section_header("Study Statistics"))

        stats_grid = QVBoxLayout()
        stats_grid.setSpacing(8)

        self.time_stat = self._create_stat_row("⏱", "Total Time", "0 min")
        self.streak_stat = self._create_stat_row("🔥", "Streak", "0 days")
        self.exercises_stat = self._create_stat_row("📝", "Exercises", "0 / 18")

        stats_grid.addWidget(self.time_stat)
        stats_grid.addWidget(self.streak_stat)
        stats_grid.addWidget(self.exercises_stat)

        layout.addLayout(stats_grid)

        layout.addWidget(self._create_separator())

        # === Current Lesson Section ===
        layout.addWidget(self._create_section_header("Current Lesson"))

        self.current_lesson_label = QLabel("No lesson selected")
        self.current_lesson_label.setStyleSheet("font-size: 10pt; color: #666; padding: 10px;")
        self.current_lesson_label.setWordWrap(True)
        layout.addWidget(self.current_lesson_label)

        # Push everything to top
        layout.addStretch()

        # Set content widget to scroll area
        scroll.setWidget(content_widget)
        main_layout.addWidget(scroll, 1)

        # Initialize with default values
        self.update_progress(0, 0, 0)

        self.setMinimumWidth(config.PROGRESS_PANEL_MIN_WIDTH)

    def _create_section_header(self, text: str) -> QLabel:
        """Create a section header label"""
        label = QLabel(text)
        label.setStyleSheet(f"font-size: 11pt; font-weight: bold; color: {config.COLOR_SECONDARY};")
        return label

    def _create_separator(self) -> QFrame:
        """Create a horizontal separator line"""
        line = QFrame()
        line.setFrameShape(QFrame.HLine)
        line.setFrameShadow(QFrame.Sunken)
        line.setStyleSheet("color: #ddd;")
        return line

    def _create_part_progress(self, part_number: int, part_title: str, progress: int) -> QWidget:
        """Create a part progress widget"""
        widget = QWidget()
        layout = QVBoxLayout(widget)
        layout.setContentsMargins(0, 5, 0, 5)
        layout.setSpacing(5)

        # Part title
        title_label = QLabel(f"Part {part_number}: {part_title[:30]}...")
        title_label.setStyleSheet("font-size: 9pt; font-weight: bold;")
        layout.addWidget(title_label)

        # Progress bar
        progress_bar = QProgressBar()
        progress_bar.setValue(progress)
        progress_bar.setStyleSheet(f"""
            QProgressBar {{
                border: 1px solid #ccc;
                border-radius: 3px;
                text-align: center;
                height: 12px;
                font-size: 8pt;
            }}
            QProgressBar::chunk {{
                background-color: {config.COLOR_PRIMARY};
            }}
        """)
        layout.addWidget(progress_bar)

        # Store reference for updates
        widget.progress_bar = progress_bar

        return widget

    def _create_stat_row(self, icon: str, label: str, value: str) -> QWidget:
        """Create a statistics row"""
        widget = QWidget()
        layout = QHBoxLayout(widget)
        layout.setContentsMargins(5, 5, 5, 5)
        layout.setSpacing(10)

        # Icon
        icon_label = QLabel(icon)
        icon_label.setStyleSheet("font-size: 16pt;")
        layout.addWidget(icon_label)

        # Label
        text_label = QLabel(label)
        text_label.setStyleSheet("font-size: 10pt; color: #666;")
        layout.addWidget(text_label)

        layout.addStretch()

        # Value
        value_label = QLabel(value)
        value_label.setStyleSheet("font-size: 10pt; font-weight: bold;")
        layout.addWidget(value_label)

        # Store reference for updates
        widget.value_label = value_label

        return widget

    def update_progress(self, completed_lessons: int, total_points: int, total_time_minutes: int):
        """Update overall progress display"""
        # Overall progress
        total_lessons = self.course.total_lessons
        progress_percent = int((completed_lessons / total_lessons) * 100) if total_lessons > 0 else 0
        self.overall_progress_bar.setValue(progress_percent)
        self.overall_stats_label.setText(f"{completed_lessons} / {total_lessons} lessons completed")

        # Points
        self.points_label.setText(f"{total_points} pts")

        # Level
        level_info = self._get_level_info(total_points)
        self.level_label.setText(f"Level {level_info['level']}: {level_info['title']}")
        self.level_progress_bar.setValue(level_info['progress'])

        # Time
        if total_time_minutes < 60:
            time_str = f"{total_time_minutes} min"
        else:
            hours = total_time_minutes // 60
            minutes = total_time_minutes % 60
            time_str = f"{hours}h {minutes}m"
        self.time_stat.value_label.setText(time_str)

    def update_part_progress(self, part_number: int, completed: int, total: int):
        """Update progress for a specific part"""
        if 0 < part_number <= len(self.part_progress_widgets):
            widget = self.part_progress_widgets[part_number - 1]
            progress = int((completed / total) * 100) if total > 0 else 0
            widget.progress_bar.setValue(progress)
            widget.progress_bar.setFormat(f"{completed}/{total} ({progress}%)")

    def update_streak(self, days: int):
        """Update study streak"""
        self.streak_stat.value_label.setText(f"{days} days")

    def update_exercises(self, completed: int, total: int):
        """Update exercise completion"""
        self.exercises_stat.value_label.setText(f"{completed} / {total}")

    def update_current_lesson(self, lesson_title: str, lesson_points: int, estimated_time: int):
        """Update current lesson information"""
        text = f"""
        <b>{lesson_title}</b><br>
        Points: {lesson_points} | Est. time: {estimated_time} min
        """
        self.current_lesson_label.setText(text)

    def _get_level_info(self, points: int) -> dict:
        """Get level information based on points"""
        for i, (threshold, title, subtitle) in enumerate(config.LEVELS):
            if i < len(config.LEVELS) - 1:
                next_threshold = config.LEVELS[i + 1][0]
                if points < next_threshold:
                    progress = int(((points - threshold) / (next_threshold - threshold)) * 100)
                    return {
                        'level': i + 1,
                        'title': title,
                        'subtitle': subtitle,
                        'progress': progress,
                        'next_threshold': next_threshold
                    }

        # Max level
        return {
            'level': len(config.LEVELS),
            'title': config.LEVELS[-1][1],
            'subtitle': config.LEVELS[-1][2],
            'progress': 100,
            'next_threshold': config.LEVELS[-1][0]
        }