import { findBestCliSkuForAcpWire, matchCliSkuToAcpWireId } from '@hapi/protocol'
import type { CursorModelCatalog } from '@/lib/cursorModelOptions'
import type { CursorModelSummary } from '@/types/api'
import {
    buildCursorCatalogFromSources,
    buildCursorPickerState,
    resolveCursorBaseFromWire,
    resolveWireIdForBaseChange,
    type CursorPickerState
} from '@/lib/cursorPickerState'

export function isCursorEffortWireInCatalog(
    wireId: string,
    catalog: CursorModelCatalog
): boolean {
    return catalog.wireToBase.has(wireId)
}

export function resolveSessionCursorBaseSelectValue(
    picker: CursorPickerState,
    cursorSelectedBase: string
): string {
    if (picker.mode !== 'dual') {
        return picker.wireId ?? 'auto'
    }
    if (cursorSelectedBase !== 'auto') {
        return cursorSelectedBase
    }
    // Catalog already reflects session.model; local base state may still be initial 'auto'.
    if (picker.baseKey && picker.baseKey !== 'auto') {
        return picker.baseKey
    }
    return 'auto'
}

export function resolveSessionCursorModelChange(args: {
    picker: CursorPickerState
    sessionModel: string | null | undefined
    cursorSelectedBase: string
    kind: 'base' | 'effort' | 'flat'
    value: string | null
}): { ok: true; wireId: string | null; nextSelectedBase: string; shouldApply: boolean } | { ok: false; reason: string } {
    const { picker, sessionModel, cursorSelectedBase, kind, value } = args

    if (kind === 'base') {
        if (!value || value === 'auto') {
            return { ok: true, wireId: null, nextSelectedBase: 'auto', shouldApply: true }
        }
        if (value.includes('[')) {
            const base = resolveCursorBaseFromWire(value, picker.catalog)
            return { ok: true, wireId: value, nextSelectedBase: base, shouldApply: true }
        }
        const wireId = resolveWireIdForBaseChange(value, picker.catalog, sessionModel)
        return {
            ok: true,
            wireId: wireId === 'auto' ? null : wireId,
            nextSelectedBase: value,
            shouldApply: wireId !== null
        }
    }

    if (kind === 'effort') {
        if (!value || value === 'auto') {
            return { ok: true, wireId: null, nextSelectedBase: cursorSelectedBase, shouldApply: true }
        }
        if (!isCursorEffortWireInCatalog(value, picker.catalog)) {
            return { ok: false, reason: 'effort wire id not in catalog' }
        }
        const base = resolveCursorBaseFromWire(value, picker.catalog)
        return { ok: true, wireId: value, nextSelectedBase: base, shouldApply: true }
    }

    // flat picker: value is wire id or auto
    if (!value || value === 'auto') {
        return { ok: true, wireId: null, nextSelectedBase: 'auto', shouldApply: true }
    }
    if (!picker.catalog.wireToBase.has(value)) {
        return { ok: false, reason: 'model wire id not in catalog' }
    }
    return {
        ok: true,
        wireId: value,
        nextSelectedBase: resolveCursorBaseFromWire(value, picker.catalog),
        shouldApply: true
    }
}

export function resolveSessionCursorVariantSelectValue(
    sessionModel: string | null | undefined,
    effortOptions: readonly { value: string }[]
): string | null {
    if (!sessionModel || effortOptions.length === 0) {
        return null
    }

    const trimmed = sessionModel.trim()
    const exact = effortOptions.find((option) => option.value === trimmed)
    if (exact) {
        return exact.value
    }

    if (trimmed.includes('[')) {
        const bestSku = findBestCliSkuForAcpWire(
            trimmed,
            effortOptions.map((option) => option.value)
        );
        if (bestSku) {
            return bestSku;
        }
    }

    return null
}

export function isSessionCursorCatalogLoading(args: {
    sessionLoading: boolean
    machineLoading: boolean
    hasMachineId: boolean
    sessionError: string | null
    machineError: string | null
}): boolean {
    if (args.sessionLoading) {
        return true
    }
    if (args.hasMachineId && args.machineLoading && !args.machineError) {
        return true
    }
    return false
}

export function isSessionCursorCatalogAwaitingSkus(args: {
    sessionLoading: boolean
    machineLoading: boolean
    sessionError: string | null
    machineError: string | null
    mergedSkus: readonly CursorModelSummary[]
    picker: CursorPickerState | null
}): boolean {
    if (args.sessionLoading || args.machineLoading) {
        return false
    }
    if (args.sessionError || args.machineError) {
        return false
    }
    if (!args.picker || args.picker.mode !== 'dual') {
        return false
    }
    if (args.mergedSkus.length > 0) {
        return false
    }
    return args.picker.showEffortPicker
}

export const SESSION_CURSOR_CATALOG_SKU_TIMEOUT_MS = 15_000

export function isSessionCursorCatalogPending(args: {
    sessionLoading: boolean
    machineLoading: boolean
    hasMachineId: boolean
    sessionError: string | null
    machineError: string | null
    mergedSkus: readonly CursorModelSummary[]
    picker: CursorPickerState | null
}): boolean {
    return isSessionCursorCatalogLoading(args)
        || isSessionCursorCatalogAwaitingSkus(args)
}

export function isSessionCursorCatalogPendingWithTimeout(args: {
    sessionLoading: boolean
    machineLoading: boolean
    hasMachineId: boolean
    sessionError: string | null
    machineError: string | null
    mergedSkus: readonly CursorModelSummary[]
    picker: CursorPickerState | null
    awaitingStartedAtMs: number | null
    nowMs?: number
    timeoutMs?: number
}): boolean {
    if (!isSessionCursorCatalogPending(args)) {
        return false
    }
    if (!isSessionCursorCatalogAwaitingSkus(args)) {
        return true
    }
    if (args.awaitingStartedAtMs === null) {
        return true
    }
    const elapsed = (args.nowMs ?? Date.now()) - args.awaitingStartedAtMs
    return elapsed < (args.timeoutMs ?? SESSION_CURSOR_CATALOG_SKU_TIMEOUT_MS)
}

export function buildSessionCursorPickerState(args: {
    sessionModels: readonly CursorModelSummary[]
    machineModels: readonly CursorModelSummary[]
    cliModelSkus?: readonly CursorModelSummary[]
    sessionModel: string | null | undefined
    sessionCurrentModelId: string | null
}): CursorPickerState {
    const catalog = buildCursorCatalogFromSources({
        sessionModels: args.sessionModels,
        machineModels: args.machineModels,
        cliModelSkus: args.cliModelSkus,
        currentWireId: args.sessionCurrentModelId ?? args.sessionModel,
        sessionModelFromHub: args.sessionModel,
        defaultValue: null
    })
    return buildCursorPickerState({
        catalog,
        currentWireId: args.sessionModel ?? args.sessionCurrentModelId,
        defaultValue: null
    })
}