# Copyright (C) 2004-2010 Tiny SPRL (<http://tiny.be>).
# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).

from odoo import fields, models
from odoo.exceptions import UserError
from odoo.tools.translate import _


class DocumentPageShowDiff(models.TransientModel):
    """Display Difference for History."""

    _name = 'wizard.document.page.history.show_diff'
    _description = 'Document Page Show Diff'

    def _get_diff(self):
        """Return the Difference between two document."""
        history = self.env["document.page.history"]
        ids = self.env.context.get('active_ids', [])
        diff = False
        if len(ids) == 2:
            if ids[0] > ids[1]:
                diff = history._get_diff(ids[1], ids[0])
            else:
                diff = history._get_diff(ids[0], ids[1])
        elif len(ids) == 1:
            diff = history.browse(ids[0]).diff
        else:
            raise UserError(
                _("Select one or maximum two history revisions!"))
        return diff

    diff = fields.Text(
        readonly=True,
        default=_get_diff,
    )