import { h, ref } from 'vue';
import { ObjectExtended } from './ObjectExtended.js';
import { EnvelopeEditor } from './EnvelopeEditor.js';
import { ShapeEditor } from './ShapeEditor.js';
import { LinkedInstrumentModal } from './LinkedInstrumentModal.js';
import { stressorToString } from '../exporter.js';

const H4 = { style: 'margin:0 0 0.5rem' };

function parseStressor(str) {
    const groups = str.split(';').map(seg =>
        seg.split(',').map(n => parseInt(n, 10)).filter(n => !isNaN(n))
    ).filter(g => g.length > 0);
    return groups.length ? { type: 'stressor', groups } : null;
}

function scoreInfoFields(info) {
    return [
        { key: 'title',     value: info?.title     ?? '', editable: true },
        { key: 'composer',  value: info?.composer   ?? '', editable: true },
        { key: 'source',    value: info?.source     ?? '', editable: true },
        { key: 'encrypter', value: info?.encrypter  ?? '', editable: true },
    ];
}

function instrFields(instr) {
    return [
        { key: 'name',             value: instr.name,                    editable: false },
        { key: 'linked',           value: instr.isLinked,                editable: false, type: 'boolean' },
        { key: 'NOT_CHANGED_SINCE', value: instr.notChangedSince ?? '—', editable: false },
    ];
}

function variationFields(v) {
    return [{ key: 'depends_on', value: v.dependsOn ?? '—', editable: true }];
}

function shapeSection(label, shape, onChange) {
    if (!shape) return null;
    return h('div', { style: 'margin-top:0.5rem' }, [
        h('strong', null, label),
        h(ShapeEditor, { shape, onChange }),
    ]);
}

export const PaneFO = {
    props: ['store'],
    setup(props) {
        const pendingEdit = ref(null);  // { instr, undo? }

        function focused() {
            const fp = props.store.focusPath;
            return fp.length ? fp[fp.length - 1] : null;
        }

        // Intercepts the first edit to a linked instrument:
        // shows embed-or-discard modal before committing. `info.undo`
        // (forwarded from ShapeEditor/EnvelopeEditor) reverts the mutation on discard.
        function makeChangeHandler(instr) {
            return (info) => {
                if (instr.isLinked && !instr.isDirty) {
                    pendingEdit.value = { instr, undo: info?.undo };
                } else {
                    instr.isDirty = true;
                    props.store.markDirty();
                }
            };
        }

        function embedInstrument(instr) {
            instr.name = instr.name.split('/').pop();
            instr.isLinked = false;
            instr.isDirty = true;
            pendingEdit.value = null;
            props.store.markDirty();
        }

        function discardEdit() {
            pendingEdit.value?.undo?.();
            pendingEdit.value = null;
        }

        function instrOnChange(instr) {
            return instr
                ? makeChangeHandler(instr)
                : () => props.store.markDirty();
        }

        return () => {
            const node = focused();
            const children = [];

            if (!node || node.type === 'score') {
                const model = props.store.scoreModel;
                if (!model) return h('div', { class: 'se-fo-pane' }, 'No score loaded');
                return h('div', { class: 'se-fo-pane' }, [
                    h('h4', H4, 'Score'),
                    h(ObjectExtended, {
                        fields: scoreInfoFields(model.info),
                        onChange: ({ key, value }) => {
                            if (!model.info) model.info = {};
                            model.info[key] = value;
                            props.store.markDirty();
                        },
                    }),
                ]);
            }

            if (node.type === 'instrument') {
                children.push(
                    h('h4', H4, `Instrument: ${node.name}`),
                    h(ObjectExtended, { fields: instrFields(node), onChange: null }),
                );
            } else if (node.type === 'variation') {
                const instr = props.store.scoreModel.instruments.find(
                    i => i.variations.includes(node) ||
                         i.variations.some(v => v.subvariations.includes(node))
                ) ?? null;
                const onChange = instrOnChange(instr);

                children.push(
                    h('h4', H4, 'Variation'),
                    h(ObjectExtended, { fields: variationFields(node), onChange: ({ key, value }) => {
                        if (key === 'depends_on') {
                            const old = node.dependsOn;
                            node.dependsOn = value;
                            onChange({ undo: () => { node.dependsOn = old; } });
                        } else {
                            onChange({});
                        }
                    }}),
                    node.basicProperties
                        ? h(EnvelopeEditor, { basicProperties: node.basicProperties, onChange })
                        : null,
                );
            } else if (node.type === 'label_spec') {
                const instr = props.store.scoreModel.instruments.find(
                    i => i.variations.some(v =>
                        v.labelSpecs.includes(node) ||
                        v.subvariations.some(sv => sv.labelSpecs.includes(node))
                    )
                ) ?? null;
                const onChange = instrOnChange(instr);

                children.push(
                    h('h4', H4, `Label: ${node.label}`),
                    node.basicProperties
                        ? h(EnvelopeEditor, { basicProperties: node.basicProperties, onChange })
                        : null,
                );
            } else if (node.type === 'bar') {
                const markBarDirty = () => { node.isDirty = true; props.store.markDirty(); };
                children.push(
                    h('h4', H4, `Bar: ${node.id}`),
                    h(ObjectExtended, {
                        fields: [
                            { key: 'id',               value: node.id,                          editable: false },
                            { key: 'beats_per_minute', value: node.tempoLevels ?? '',           editable: true, type: 'number' },
                            { key: 'stress_pattern',   value: stressorToString(node.stressor),  editable: true },
                        ],
                        onChange: ({ key, value }) => {
                            if (key === 'beats_per_minute') node.tempoLevels = isNaN(value) ? null : value;
                            if (key === 'stress_pattern')   node.stressor    = parseStressor(value);
                            markBarDirty();
                        },
                    }),
                    shapeSection('Upper stress bound', node.upperStressBound, markBarDirty),
                    shapeSection('Lower stress bound', node.lowerStressBound, markBarDirty),
                    shapeSection('Tempo shape',        node.tempoShape,       markBarDirty),
                );
            } else if (node.type === 'voice') {
                children.push(
                    h('h4', H4, `Voice: ${node.name}`),
                    h(ObjectExtended, {
                        fields: [
                            { key: 'articles', value: node.articles.join(', ') || '—', editable: false },
                            { key: 'motifs',   value: node.motifs.join(', ')   || '—', editable: false },
                            { key: 'offsets',  value: String(node.offsets.length),     editable: false },
                        ],
                        onChange: null,
                    }),
                );
            } else if (node.type === 'offset') {
                const noteStr    = n => `${n.pitch}${n.effLength != null ? ' ' + n.effLength : ''}`;
                const clusterStr = c => c.notes.length
                    ? c.notes.map(n => `${n.letter ?? ''}${n.shift != null ? n.shift : ''}${n.length != null ? ' ' + n.length : ''}`).join(', ')
                    : `cluster[${c.index}]`;
                const noteItem = (text, i) => h('li', { class: 'se-object-item', key: i },
                    h('span', { class: 'se-object-label' }, text));

                children.push(
                    h('h4', H4, `Tick: ${node.tick}`),
                    h(ObjectExtended, {
                        fields: [{ key: 'tick', value: node.tick, editable: false }],
                        onChange: null,
                    }),
                    node.stemNotes.length ? h('div', { style: 'margin-top:0.5rem' }, [
                        h('strong', null, 'Stem notes'),
                        h('ul', { class: 'se-object-list' }, node.stemNotes.map((n, i) => noteItem(noteStr(n), i))),
                    ]) : null,
                    node.clusters.length ? h('div', { style: 'margin-top:0.5rem' }, [
                        h('strong', null, 'Clusters'),
                        h('ul', { class: 'se-object-list' }, node.clusters.map((c, i) => noteItem(clusterStr(c), i))),
                    ]) : null,
                );
            } else {
                children.push(h('pre', { style: 'font-size:0.75rem;white-space:pre-wrap' },
                    JSON.stringify(node, null, 2)));
            }

            return h('div', { class: 'se-fo-pane' }, [
                ...children,
                pendingEdit.value
                    ? h(LinkedInstrumentModal, {
                        instrumentName: pendingEdit.value.instr.name,
                        onEmbed:    () => embedInstrument(pendingEdit.value.instr),
                        onDiscard:  discardEdit,
                      })
                    : null,
            ]);
        };
    },
};