import { nanoid } from 'nanoid';
import * as schema from '~~/drizzle/schema';

export type Model = typeof schema.models.$inferSelect;
export type Provider = typeof schema.providers.$inferSelect;

export type ProviderWithModels = Provider & {
    models: Model[];
};

export type ModelWithProvider = Model & {
    provider: Provider;
};

export const useModels = async () => {
    const providers = useState<ProviderWithModels[]>('models_state', () => []);
    const loaded = useState('models_loaded', () => false);

    const { refresh } = await useFetch<ProviderWithModels[]>('/api/providers', {
        key: 'models_request',
        immediate: !loaded.value,
        onRequest() {
            loaded.value = true;
        },
        onResponse({ response }) {
            if (response.ok) {
                providers.value = response._data ?? [];
            }
        }
    });

    const allModels = computed<ModelWithProvider[]>(() => {
        const result: ModelWithProvider[] = [];
        for (const provider of providers.value) {
            if (!provider.enabled) continue;
            for (const model of provider.models || []) {
                if (!model.enabled) continue;
                result.push({ ...model, provider });
            }
        }
        return result;
    });

    const getModel = (id: string): ModelWithProvider | undefined => {
        return allModels.value.find((model) => model.id === id);
    };

    const getProvider = (id: string): ProviderWithModels | undefined => {
        return providers.value.find((provider) => provider.id === id);
    };

    const getFirstAvailableModel = () => {
        return allModels.value[0] ?? null;
    };

    const createModel = async (model: Model) => {
        model.id = nanoid();
        await $fetch(`/api/model`, {
            method: 'POST',
            body: model,
            onRequest() {
                providers.value = providers.value.map(p => ({
                    ...p,
                    models: p.id === model.providerId ? [...p.models, model] : p.models
                }));
            },
            onResponseError() {
                providers.value = providers.value.map(p => ({
                    ...p,
                    models: p.id === model.providerId ? p.models.filter(m => m.id !== model.id) : p.models
                }));
            },
        });
    }

    const updateModel = async (id: string, updates: Partial<Model>) => {
        const model = providers.value.find(p => p.models.find(m => m.id === id));
        if (!model) return;

        const original = model;

        await $fetch(`/api/model/${id}`, {
            method: 'PATCH',
            body: updates,
            onRequest() {
                providers.value = providers.value.map(p => ({
                    ...p,
                    models: p.models.map(m =>
                        m.id === id ? { ...m, ...updates } : m
                    )
                }));
            },
            onRequestError() {
                providers.value = providers.value.map(p => ({
                    ...p,
                    models: p.models.map(m =>
                        m.id === id ? original : m
                    )
                }) as ProviderWithModels);
            },
            onResponseError() {
                providers.value = providers.value.map(p => ({
                    ...p,
                    models: p.models.map(m =>
                        m.id === id ? original : m
                    )
                }) as ProviderWithModels);
            },
            // async onResponse() {
            //     await refresh();
            // }
        });
    };

    const deleteModel = async (id: string) => {
        const model = providers.value.find(p => p.models.find(m => m.id === id));
        if (!model) return;

        await $fetch(`/api/model/${id}`, {
            method: 'DELETE',
            onRequest() {
                providers.value = providers.value.map(p => ({
                    ...p,
                    models: p.models.filter(m => m.id !== id)
                }));
            },
            onResponseError() {
                providers.value.push(model);
            },
            async onResponse() {
                await refresh();
            }
        });
    }

    const updateProvider = async (id: string, updates: Partial<Provider>) => {
        const provider = providers.value.find(p => p.id === id);
        if (!provider) return;

        const original = provider;

        await $fetch(`/api/provider/${id}`, {
            method: 'PATCH',
            body: updates,
            onRequest() {
                providers.value = providers.value.map(p =>
                    p.id === id ? { ...p, ...updates } : p
                );
            },
            onRequestError() {
                providers.value = providers.value.map(p =>
                    p.id === id ? original : p
                );
            },
            onResponseError() {
                providers.value = providers.value.map(p =>
                    p.id === id ? original : p
                );
            },
            async onResponse() {
                await refresh();
            }
        });
    };

    return {
        providers,
        allModels,
        getModel,
        getProvider,
        getFirstAvailableModel,
        createModel,
        updateModel,
        updateProvider,
        deleteModel
    };
}