from django.core import mail
from django.contrib import admin, messages
from django.db.models import Value
from django.db.models.functions import Now, Concat, LPad

from .models import (
    CmsRedRiverVeteransScholarship,
    Department,
    CertificationDefinition,
    Certification,
    CertificationVersion,
    InstructorOrVendor,
    SpecialProgram,
    Waiver,
)
from .forms import CertificationForm
from .certification_emails import all_certification_emails


@admin.register(Department)
class DepartmentAdmin(admin.ModelAdmin):
    search_fields = ["name"]
    list_display = [
        "name",
        "parent",
        "has_mailing_list",
        "shop_lead_flag",
        "list_reply_to_address",
    ]


class CertificationVersionInline(admin.TabularInline):
    model = CertificationVersion
    extra = 1

    readonly_fields = (
        "semantic_version",
        "is_latest",
        "is_current",
    )

    @admin.display(description="Latest", boolean=True)
    def is_latest(self, obj):
        return obj.is_latest

    @admin.display(description="Current", boolean=True)
    def is_current(self, obj):
        return obj.is_current


@admin.register(CertificationDefinition)
class CertificationDefinitionAdmin(admin.ModelAdmin):
    search_fields = ["certification_name"]
    list_display = [
        "certification_name",
        "department",
        "latest_semantic_version",
    ]
    list_filter = ["department"]
    inlines = [CertificationVersionInline]

    @admin.display(description="Latest Version")
    def latest_semantic_version(self, obj):
        return obj.latest_version().semantic_version()


@admin.register(Certification)
class CertificationAdmin(admin.ModelAdmin):
    form = CertificationForm
    search_fields = [
        "name",
        "certification_version__definition__certification_name",
        "certification_version__definition__department__name",
    ]
    autocomplete_fields = ["member"]
    exclude = ["shop_lead_notified"]

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        return qs.prefetch_related("certification_version__definition__department")

    @admin.display(
        description="Certification Name",
        ordering="certification_version__definition__certification_name",
    )
    def certification_name(self, obj):
        return obj.certification_version.definition.certification_name

    @admin.display(
        description="Certification Version",
        ordering=(
            Concat(
                LPad("certification_version__major", 4, Value("0")),
                LPad("certification_version__minor", 4, Value("0")),
                LPad("certification_version__patch", 4, Value("0")),
                "certification_version__prerelease",
                "certification_version__approval_date",
            )
        ),
    )
    def certification_semantic_version(self, obj):
        return obj.certification_version.semantic_version()

    @admin.display(description="Current", boolean=True)
    def is_current(self, obj):
        return obj.certification_version.is_current

    @admin.display(
        description="Department",
        ordering="certification_version__definition__department",
    )
    def certification_department(self, obj):
        return obj.certification_version.definition.department

    list_display = [
        "certification_name",
        "name",
        "certification_semantic_version",
        "is_current",
        "certification_department",
        "date",
        "shop_lead_notified",
        "certified_by",
    ]
    list_display_links = [
        "certification_name",
        "name",
    ]
    list_filter = [
        "certification_version__definition__department",
        ("shop_lead_notified", admin.EmptyFieldListFilter),
    ]

    actions = ["send_notifications"]

    @admin.action(
        description="Notify Shop Leads and Members of selected certifications"
    )
    def send_notifications(self, request, queryset):
        try:
            emails = list(all_certification_emails(queryset))

            with mail.get_connection() as conn:
                conn.send_messages(emails)

            for cert in queryset:
                cert.shop_lead_notified = Now()
                cert.save()

            self.message_user(
                request,
                f"{len(emails)} notifications sent for {len(queryset)} certifications",
                messages.SUCCESS,
            )
        except Exception as e:
            self.message_user(
                request,
                f"Failed to send notifications! {e}",
                messages.ERROR,
            )
            raise


@admin.register(InstructorOrVendor)
class InstructorOrVendorAdmin(admin.ModelAdmin):
    search_fields = ["name"]
    list_display = [
        "name",
        "instructor_agreement_date",
        "w9_date",
        "phone",
        "email_address",
    ]


@admin.register(SpecialProgram)
class SpecialProgramAdmin(admin.ModelAdmin):
    search_fields = ["program_name"]
    list_display = [
        "program_name",
        "discount_percent",
        "discount_code",
        "membership_code",
        "start_date",
        "end_date",
        "program_amount",
        "program_status",
    ]


@admin.register(Waiver)
class WaiverAdmin(admin.ModelAdmin):
    search_fields = ["name"]

    list_display = [
        "name",
        "date",
        "emergency_contact_name",
        "emergency_contact_number",
        "waiver_version",
        "guardian_name",
        "guardian_relation",
        "guardian_date",
    ]


admin.site.register(CmsRedRiverVeteransScholarship)