from odoo import models, fields, api
from odoo.exceptions import AccessError

class EducationLMSCourse(models.Model):
    _name = 'education.lms.course'
    _description = 'LMS Course'
    
    name = fields.Char(string='Name', required=True)
    subject_id = fields.Many2one('education.subject', string='Subject', required=True)
    program_id = fields.Many2one('education.program', string='Program', required=True)
    academic_year_id = fields.Many2one('education.academic.year', string='Academic Year', required=True)
    term_id = fields.Many2one('education.academic.term', string='Term')
    batch_id = fields.Many2one('education.batch', string='Batch')
    
    faculty_id = fields.Many2one('res.users', string='Faculty / Instructor', required=True, default=lambda self: self.env.user)
    
    description = fields.Html(string='Description')
    
    state = fields.Selection([
        ('draft', 'Draft'),
        ('published', 'Published'),
        ('archived', 'Archived')
    ], string='State', default='draft', required=True)
    
    active = fields.Boolean(default=True)
    
    section_ids = fields.One2many('education.lms.section', 'course_id', string='Sections')
    assignment_ids = fields.One2many('education.lms.assignment', 'course_id', string='Assignments')
    
    assignment_count = fields.Integer(string='Assignment Count', compute='_compute_assignment_count')
    submission_count = fields.Integer(string='Submission Count', compute='_compute_submission_count')
    
    @api.depends('assignment_ids')
    def _compute_assignment_count(self):
        for record in self:
            record.assignment_count = len(record.assignment_ids)
            
    def _compute_submission_count(self):
        for record in self:
            submissions = self.env['education.lms.submission'].search([('assignment_id.course_id', '=', record.id)])
            record.submission_count = len(submissions)
            
    def action_publish(self):
        for record in self:
            record.state = 'published'
            
    def action_draft(self):
        for record in self:
            record.state = 'draft'
            
    def action_archive(self):
        for record in self:
            record.state = 'archived'
    
    @api.constrains('faculty_id')
    def _check_faculty_ownership(self):
        if self.env.su or self.env.user.has_group('education_lms.group_education_lms_admin'):
            return
        for record in self:
            if record.faculty_id.id != self.env.user.id:
                raise AccessError("Faculty members can only manage courses assigned to themselves. Ownership cannot be transferred or spoofed.")

    def write(self, vals):
        if not self.env.su and not self.env.user.has_group('education_lms.group_education_lms_admin'):
            for record in self:
                if record.faculty_id.id != self.env.user.id:
                    raise AccessError("You can only edit courses assigned to you.")
        return super().write(vals)
        
    def unlink(self):
        if not self.env.su and not self.env.user.has_group('education_lms.group_education_lms_admin'):
            for record in self:
                if record.faculty_id.id != self.env.user.id:
                    raise AccessError("You can only delete courses assigned to you.")
        return super().unlink()