// persona-kb.js — Persona–Knowledge Base binding UI (v0.17.0)
//
// Provides renderPersonaKBPicker(container, opts) which renders a multi-select
// KB picker with auto_search toggles for use in persona create/edit forms.
// Pattern: (container, options) → control object with getValues/setValues/clear.

'use strict';

// ── Persona-KB Picker ───────────────────────────

/**
 * Renders a KB picker into a container element.
 *
 * Options:
 *   scope    - 'admin' | 'team' | 'personal' — controls which KBs are shown
 *   teamId   - required for team scope
 *   prefix   - DOM id prefix (default: 'pkb')
 *
 * Returns: { getValues(), setValues(kbs), clear(), refresh() }
 */
function renderPersonaKBPicker(containerEl, options = {}) {
    const pfx = options.prefix || 'pkb';
    let _allKBs = [];     // available KBs from server
    let _selected = {};   // kb_id → { selected: bool, auto_search: bool }

    containerEl.innerHTML = `
        <div class="persona-kb-picker" id="${pfx}_picker">
            <label>Knowledge Bases</label>
            <div class="form-hint">Bind KBs to this persona — users will search these KBs automatically when using this persona.</div>
            <div class="persona-kb-list" id="${pfx}_list">
                <div class="empty-hint">Loading knowledge bases…</div>
            </div>
        </div>
    `;

    // ── Load available KBs ──
    async function loadKBs() {
        try {
            let resp;
            if (options.scope === 'team' && options.teamId) {
                resp = await API._get(`/api/v1/teams/${options.teamId}/knowledge-bases`);
            } else if (options.scope === 'admin') {
                resp = await API._get('/api/v1/knowledge-bases');
            } else {
                // User scope — show discoverable KBs
                resp = await API._get('/api/v1/knowledge-bases-discoverable');
            }
            _allKBs = (resp.data || []).filter(kb => kb.chunk_count > 0);
        } catch (e) {
            _allKBs = [];
        }
        render();
    }

    // ── Render KB list ──
    function render() {
        const list = document.getElementById(`${pfx}_list`);
        if (!list) return;

        if (_allKBs.length === 0) {
            list.innerHTML = '<div class="empty-hint">No knowledge bases with content available.</div>';
            return;
        }

        list.innerHTML = _allKBs.map(kb => {
            const sel = _selected[kb.id] || { selected: false, auto_search: false };
            return `
                <label class="persona-kb-item ${sel.selected ? 'selected' : ''}">
                    <input type="checkbox" data-kb-id="${esc(kb.id)}" ${sel.selected ? 'checked' : ''}>
                    <span class="kb-name">${esc(kb.name)}</span>
                    <span class="kb-meta">${kb.document_count} docs · ${kb.chunk_count} chunks</span>
                    <label class="auto-search-toggle ${sel.selected ? '' : 'hidden'}" title="Auto-inject top results into context (no tool call needed)">
                        <input type="checkbox" data-kb-auto="${esc(kb.id)}" ${sel.auto_search ? 'checked' : ''}>
                        <span>Auto-inject</span>
                    </label>
                </label>`;
        }).join('');

        // Wire checkboxes
        list.querySelectorAll('input[data-kb-id]').forEach(cb => {
            cb.addEventListener('change', function() {
                const kbId = this.dataset.kbId;
                if (!_selected[kbId]) _selected[kbId] = { selected: false, auto_search: false };
                _selected[kbId].selected = this.checked;
                render();
            });
        });

        list.querySelectorAll('input[data-kb-auto]').forEach(cb => {
            cb.addEventListener('change', function() {
                const kbId = this.dataset.kbAuto;
                if (_selected[kbId]) {
                    _selected[kbId].auto_search = this.checked;
                }
            });
        });
    }

    // ── Control object ──
    const control = {
        getValues() {
            const kbIds = [];
            const autoSearch = {};
            for (const [kbId, state] of Object.entries(_selected)) {
                if (state.selected) {
                    kbIds.push(kbId);
                    if (state.auto_search) {
                        autoSearch[kbId] = true;
                    }
                }
            }
            return { kb_ids: kbIds, auto_search: autoSearch };
        },

        setValues(personaKBs) {
            _selected = {};
            if (Array.isArray(personaKBs)) {
                for (const pkb of personaKBs) {
                    _selected[pkb.kb_id] = {
                        selected: true,
                        auto_search: !!pkb.auto_search,
                    };
                }
            }
            render();
        },

        clear() {
            _selected = {};
            render();
        },

        async refresh() {
            await loadKBs();
        }
    };

    // Auto-load on create
    loadKBs();

    return control;
}


// ── Persona-KB Save/Load Helpers ────────────────

/**
 * Load persona KB bindings and populate the picker.
 * @param {string} personaId
 * @param {object} kbPicker - control object from renderPersonaKBPicker
 * @param {string} apiPrefix - e.g. '/api/v1/admin' or '/api/v1/teams/:teamId'
 */
async function loadPersonaKBs(personaId, kbPicker, apiPrefix) {
    if (!personaId || !kbPicker) return;
    try {
        const resp = await API._get(`${apiPrefix}/personas/${personaId}/knowledge-bases`);
        kbPicker.setValues(resp.data || []);
    } catch (e) {
        console.warn('Failed to load persona KBs:', e.message);
    }
}

/**
 * Save persona KB bindings from the picker.
 * @param {string} personaId
 * @param {object} kbPicker - control object from renderPersonaKBPicker
 * @param {string} apiPrefix - e.g. '/api/v1/admin' or '/api/v1/teams/:teamId'
 */
async function savePersonaKBs(personaId, kbPicker, apiPrefix) {
    if (!personaId || !kbPicker) return;
    const values = kbPicker.getValues();
    try {
        await API._put(`${apiPrefix}/personas/${personaId}/knowledge-bases`, values);
    } catch (e) {
        console.warn('Failed to save persona KBs:', e.message);
    }
}