"use client"

import { AlertTriangle, Plus, Save } from "lucide-react"

import { Button } from "@/shared/components/ui/button"
import { Alert, AlertTitle } from "@/shared/components/ui/alert"
import { FieldGroup } from "@/shared/components/ui/field"
import { Card, CardContent, CardHeader, CardTitle } from "@/shared/components/ui/card"
import {
    Rhform,
    RhfTextField,
    RhfSelectField,
    RhfAsyncSelectField,
    RhfTextareaField,
    RhfDateField,
} from "@/shared/components/form"
import { toast } from "sonner"
import { useAuthApi } from "@/shared/useApi"
import { useResourceForm } from "@/shared/hooks/use-resource-form"
import { useFormMutation } from "@/shared/hooks/use-form-mutation"
import { getTodayDate, toRelation, toId } from "@/shared/lib/utils"
import { formatTaxLabel } from "@/shared/utils/formatters"

import {
    expenseFormSchema,
    type ExpenseFormValues,
} from "./expense.schema"
import {
    EXPENSE_ROUTES,
    JOB_CARD_ROUTES,
    VENDOR_ROUTES,
    DEPARTMENT_ROUTES,
    INVENTORY_CATEGORY_ROUTES,
    TAX_ROUTES,
    ExpenseStatus,
    InvoiceDiscount,
} from "@garage/api"
import { useFormContext } from "react-hook-form"
import { RhfLabelPickerField, type LabelItem } from "@/modules/labels/rhf-label-picker-field"
import { ExpenseItemsSelectorField } from "@/modules/expense-items/expense-items-selector-field"
import { InventoryCategoryCrudDialog } from "@/modules/expense-items/inventory-category-crud-dialog"
import { ExpenseFormSummary } from "./expense-form-summary"

// ── Constants ──

const STATUS_OPTIONS = ExpenseStatus.map((value) => ({
    value,
    label: value.replace(/_/g, " ").replace(/\b\w/g, (char) => char.toUpperCase()),
}))

const DISCOUNT_OPTIONS = InvoiceDiscount.map((v) => ({
    value: v,
    label: v.replace(/_/g, " ").replace(/\b\w/g, (c) => c.toUpperCase()),
}))

// ── Props ──

export type ExpenseFormProps = {
    resourceId?: string | null
    initialData?: unknown
    onSuccess?: () => void
}

// ── Default values ──

const DEFAULT_VALUES: ExpenseFormValues = {
    job_card: null,
    category: null,
    vendor: null,
    department: null,
    tax: null,
    title: "",
    invoice_number: "",
    expense_date: getTodayDate(),
    notes: "",
    status: "open",
    discount: "no",
    discount_amount: undefined,
    labels: [],
    items: [],
}

// ── Mapping helpers ──

function mapToFormValues(data: unknown): ExpenseFormValues {
    const d = (data as any)?.data ?? data ?? {}

    return {
        job_card: toRelation(d.job_card_id, d.job_card?.order_number ?? d.job_card_name),
        category: toRelation(d.category_id, d.category?.name ?? d.category?.title ?? d.category_name),
        vendor: toRelation(d.vendor_id, d.vendor?.company_name ?? d.vendor?.name ?? d.vendor_name),
        department: toRelation(d.department_id, d.department?.name ?? d.department_name),
        tax: toRelation(d.tax_id, formatTaxLabel(d.tax, d.tax_title ?? "") || undefined),
        title: d.title || "",
        invoice_number: d.invoice_number || "",
        expense_date: d.expense_date ? d.expense_date.split("T")[0] : "",
        notes: d.notes || "",
        status: d.status || "open",
        discount: d.discount || "no",
        discount_amount: d.discount_amount != null ? Number(d.discount_amount) : undefined,
        labels: (d.labels ?? []).map((label: any): LabelItem => ({
            id: Number(label.id),
            title: label.title ?? label.name ?? "",
            color_code: label.color_code ?? "",
        })),
        items: (d.expense_items ?? d.items ?? []).map((item: any) => ({
            expense_id: item.expense_item_id ?? item.expense_item?.id ?? item.id,
            title: item.expense_item?.item_name ?? item.expense_item?.name ?? item.item_name ?? item.title ?? "",
            quantity: Number(item.quantity) || 1,
            rate: Number(item.rate) || 0,
            discount_amount: item.discount_amount != null ? Number(item.discount_amount) : undefined,
            chart_of_account: item.chart_of_account != null ? String(item.chart_of_account) : "",
            description: item.description ?? "",
        })),
    }
}

function mapFormToPayload(values: ExpenseFormValues) {
    return {
        job_card_id: toId(values.job_card),
        category_id: toId(values.category),
        vendor_id: toId(values.vendor),
        department_id: toId(values.department),
        tax_id: toId(values.tax) ? Number(toId(values.tax)) : undefined,
        title: values.title,
        invoice_number: values.invoice_number || undefined,
        expense_date: values.expense_date || undefined,
        notes: values.notes || undefined,
        status: values.status || undefined,
        discount: values.discount || undefined,
        discount_amount: values.discount === "transaction_level" ? (values.discount_amount ?? 0) : undefined,
        label_ids: values.labels?.map((label) => label.id) ?? [],
        items: (values.items ?? []).map((item) => ({
            expense_item_id: item.expense_id,
            quantity: item.quantity,
            rate: item.rate,
            discount_amount: values.discount === "line_item_level" ? (item.discount_amount ?? 0) : undefined,
            chart_of_account: item.chart_of_account || undefined,
            description: item.description || undefined,
        })),
    }
}

// ── Shared mapOption for async selects ──

const mapLookupOption = (item: any) => ({
    value: String(item.id),
    label: item.name ?? item.title ?? `#${item.id}`,
})

const mapVendorOption = (item: any) => ({
    value: String(item.id),
    label: item.company_name ?? item.name ?? `#${item.id}`,
})

const STORE_OBJECT = { getOptionValue: (o: any) => o, getOptionLabel: (o: any) => o.label }

// ── Transaction-level discount amount field ──

function TransactionDiscountField() {
    const { watch } = useFormContext<ExpenseFormValues>()
    const discount = watch("discount")
    if (discount !== "transaction_level") return null
    return (
        <RhfTextField
            name="discount_amount"
            label="Discount Amount"
            type="number"
            placeholder="0.00"
        />
    )
}

// ── Component ──

export function ExpenseForm({ resourceId, initialData, onSuccess }: ExpenseFormProps) {
    const api = useAuthApi()

    const { form, isEditing } = useResourceForm<ExpenseFormValues, any>({
        schema: expenseFormSchema,
        defaultValues: DEFAULT_VALUES,
        resourceId,
        initialData,
        queryKey: [EXPENSE_ROUTES.BY_ID, resourceId],
        mapToFormValues,
    })

    const discount = form.watch("discount")
    const isLineItemDiscount = discount === "line_item_level"

    const { mutate, error, isPending } = useFormMutation(form, {
        mutationFn: (values: ExpenseFormValues) => {
            const payload = mapFormToPayload(values)
            const promise = (isEditing && resourceId
                ? api.expenses.update(resourceId, payload as any)
                : api.expenses.create(payload as any)) as Promise<any>
            toast.promise(promise, {
                loading: isEditing ? "Updating expense..." : "Creating expense...",
                success: isEditing ? "Expense updated successfully" : "Expense created successfully",
                error: isEditing ? "Failed to update expense" : "Failed to create expense",
            })
            return promise
        },
        onSuccess: () => {
            form.reset()
            onSuccess?.()
        },
    })

    return (
        <Rhform form={form} onSubmit={(values) => mutate(values)}>
            {error && (
                <Alert variant="destructive" className="mb-4">
                    <AlertTriangle className="me-2 h-4 w-4" />
                    <AlertTitle>
                        {isEditing ? "Failed to update expense" : "Failed to create expense"}
                    </AlertTitle>
                    {error.message}
                </Alert>
            )}

            <div className="grid grid-cols-1 gap-6 lg:grid-cols-12">
                <div className="lg:col-span-9">
                    <FieldGroup>
                        <RhfTextField name="title" label="Title" placeholder="Enter expense title" required />

                        <div className="grid grid-cols-1 gap-4 sm:grid-cols-2">
                            <RhfTextField name="invoice_number" label="Invoice Number" placeholder="INV-001" />
                            <RhfSelectField
                                name="status"
                                label="Status"
                                placeholder="Select status"
                                options={STATUS_OPTIONS}
                            />
                        </div>

                        <RhfSelectField
                            name="discount"
                            label="Discount Type"
                            options={DISCOUNT_OPTIONS}
                        />

                        <TransactionDiscountField />

                        <ExpenseItemsSelectorField<ExpenseFormValues, "items">
                            name="items"
                            label="Expense Items"
                            triggerLabel="Add Expense Items"
                            showChartOfAccount
                            showDiscount={isLineItemDiscount}
                        />

                        <RhfTextareaField
                            name="notes"
                            label="Notes"
                            rows={3}
                            placeholder="Additional notes"
                        />

                        <Button type="submit" variant="default" disabled={isPending}>
                            {isEditing ? <Save /> : <Plus />}
                            {isPending
                                ? (isEditing ? "Updating..." : "Creating...")
                                : (isEditing ? "Update Expense" : "Create Expense")}
                        </Button>
                    </FieldGroup>
                </div>

                <div className="lg:col-span-3">
                    <Card>
                        <CardHeader className="pb-3">
                            <CardTitle className="text-sm font-medium text-muted-foreground uppercase tracking-wide">
                                Details
                            </CardTitle>
                        </CardHeader>
                        <CardContent>
                            <FieldGroup>
                                <RhfDateField name="expense_date" label="Expense Date" />

                                <RhfAsyncSelectField
                                    name="tax"
                                    label="Tax"
                                    placeholder="Select tax rate"
                                    queryKey={[TAX_ROUTES.INDEX]}
                                    listFn={() => api.taxes.list()}
                                    mapOption={(item: any) => ({
                                        value: String(item.id),
                                        label: item.title ? `${item.title} (${item.rate}%)` : `#${item.id}`,
                                    })}
                                    {...STORE_OBJECT}
                                />

                                <RhfAsyncSelectField
                                    name="vendor"
                                    label="Vendor"
                                    placeholder="Select vendor"
                                    queryKey={[VENDOR_ROUTES.INDEX]}
                                    listFn={() => api.vendors.list()}
                                    mapOption={mapVendorOption}
                                    {...STORE_OBJECT}
                                />

                                <RhfAsyncSelectField
                                    name="department"
                                    label="Department"
                                    placeholder="Select department"
                                    queryKey={[DEPARTMENT_ROUTES.INDEX]}
                                    listFn={() => api.departments.list()}
                                    mapOption={mapLookupOption}
                                    {...STORE_OBJECT}
                                />

                                <RhfAsyncSelectField
                                    name="job_card"
                                    label="Job Card"
                                    placeholder="Select job card"
                                    queryKey={[JOB_CARD_ROUTES.INDEX]}
                                    listFn={() => api.jobCards.list()}
                                    mapOption={(item: any) => ({
                                        value: String(item.id),
                                        label: item.order_number ?? item.estimate_number ?? `#${item.id}`,
                                    })}
                                    {...STORE_OBJECT}
                                />

                                <div>
                                    <div className="mb-1 flex items-center justify-between">
                                        <span className="text-sm font-medium">Category</span>
                                        <InventoryCategoryCrudDialog />
                                    </div>
                                    <RhfAsyncSelectField
                                        name="category"
                                        label=""
                                        placeholder="Select category"
                                        queryKey={[INVENTORY_CATEGORY_ROUTES.INDEX]}
                                        listFn={() => api.inventoryCategories.list()}
                                        mapOption={mapLookupOption}
                                        {...STORE_OBJECT}
                                    />
                                </div>

                                <RhfLabelPickerField name="labels" label="Labels" />
                            </FieldGroup>
                        </CardContent>
                    </Card>

                    <div className="mt-4">
                        <ExpenseFormSummary />
                    </div>
                </div>
            </div>
        </Rhform>
    )
}