# Copyright (C) 2013 Savoir-faire Linux (<http://www.savoirfairelinux.com>).
# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).

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


class DocumentPageHistory(models.Model):
    """Useful to manage edition's workflow on a document."""

    _name = "document.page.history"
    _inherit = ["document.page.history", "mail.thread"]

    state = fields.Selection(
        [
            ("draft", "Draft"),
            ("to approve", "Pending Approval"),
            ("approved", "Approved"),
            ("cancelled", "Cancelled"),
        ],
        "Status",
        default="draft",
        readonly=True,
    )

    approved_date = fields.Datetime("Approved Date",)

    approved_uid = fields.Many2one("res.users", "Approved by",)

    is_approval_required = fields.Boolean(
        related="page_id.is_approval_required", string="Approval required",
    )

    am_i_owner = fields.Boolean(compute="_compute_am_i_owner")

    am_i_approver = fields.Boolean(related="page_id.am_i_approver", related_sudo=False,)

    page_url = fields.Text(compute="_compute_page_url", string="URL",)

    @api.multi
    def action_draft(self):
        """Set a change request as draft"""
        for rec in self:
            if not rec.state == "cancelled":
                raise UserError(_("You need to cancel it before reopening."))
            if not (rec.am_i_owner or rec.am_i_approver):
                raise UserError(
                    _(
                        "You are not authorized to do this.\r\n"
                        "Only owners or approvers can reopen Change Requests."
                    )
                )
            rec.write({"state": "draft"})

    @api.multi
    def action_to_approve(self):
        """Set a change request as to approve"""
        template = self.env.ref(
            "document_page_approval.email_template_new_draft_need_approval"
        )
        approver_gid = self.env.ref(
            "document_page_approval.group_document_approver_user"
        )
        for rec in self:
            if rec.state != "draft":
                raise UserError(_("Can't approve pages in '%s' state.") % rec.state)
            if not (rec.am_i_owner or rec.am_i_approver):
                raise UserError(
                    _(
                        "You are not authorized to do this.\r\n"
                        "Only owners or approvers can request approval."
                    )
                )
            # request approval
            if rec.is_approval_required:
                rec.write({"state": "to approve"})
                guids = [g.id for g in rec.page_id.approver_group_ids]
                users = self.env["res.users"].search(
                    [("groups_id", "in", guids), ("groups_id", "in", approver_gid.id)]
                )
                rec.message_subscribe([u.id for u in users])
                rec.message_post_with_template(template.id)
            else:
                # auto-approve if approval is not required
                rec.action_approve()

    @api.multi
    def action_approve(self):
        """Set a change request as approved."""
        for rec in self:
            if rec.state not in ["draft", "to approve"]:
                raise UserError(_("Can't approve page in '%s' state.") % rec.state)
            if not rec.am_i_approver:
                raise UserError(
                    _(
                        "You are not authorized to do this.\r\n"
                        "Only approvers with these groups can approve this: "
                    )
                    % ", ".join(
                        [g.display_name for g in rec.page_id.approver_group_ids]
                    )
                )
            # Update state
            rec.write(
                {
                    "state": "approved",
                    "approved_date": fields.datetime.now(),
                    "approved_uid": self.env.uid,
                }
            )
            # Trigger computed field update
            rec.page_id._compute_history_head()
            # Notify state change
            rec.message_post(
                subtype="mt_comment",
                body=_("Change request has been approved by %s.")
                % (self.env.user.name),
            )
            # Notify followers a new version is available
            rec.page_id.message_post(
                subtype="mt_comment",
                body=_("New version of the document %s approved.") % (rec.page_id.name),
            )

    @api.multi
    def action_cancel(self):
        """Set a change request as cancelled."""
        self.write({"state": "cancelled"})
        for rec in self:
            rec.message_post(
                subtype="mt_comment",
                body=_("Change request <b>%s</b> has been cancelled by %s.")
                % (rec.display_name, self.env.user.name),
            )

    @api.multi
    def action_cancel_and_draft(self):
        """Set a change request as draft, cancelling it first"""
        self.action_cancel()
        self.action_draft()

    @api.multi
    def _compute_am_i_owner(self):
        """Check if current user is the owner"""
        for rec in self:
            rec.am_i_owner = rec.create_uid == self.env.user

    @api.multi
    def _compute_page_url(self):
        """Compute the page url."""
        for page in self:
            base_url = (
                self.env["ir.config_parameter"]
                .sudo()
                .get_param("web.base.url", default="http://localhost:8069")
            )

            page.page_url = (
                "{}/web#db={}&id={}&view_type=form&" "model=document.page.history"
            ).format(base_url, self.env.cr.dbname, page.id)

    @api.multi
    def _compute_diff(self):
        """Shows a diff between this version and the previous version"""
        history = self.env["document.page.history"]
        for rec in self:
            domain = [("page_id", "=", rec.page_id.id), ("state", "=", "approved")]
            if rec.approved_date:
                domain.append(("approved_date", "<", rec.approved_date))
            prev = history.search(domain, limit=1, order="approved_date DESC")
            if prev:
                rec.diff = self._get_diff(prev.id, rec.id)
            else:
                rec.diff = self._get_diff(False, rec.id)